1
|
Maleki T, Meinen J, Coldea A, Reymus M, Edelhoff D, Stawarczyk B. Mechanical and physical properties of splint materials for oral appliances produced by additive, subtractive and conventional manufacturing. Dent Mater 2024; 40:1171-1183. [PMID: 38851965 DOI: 10.1016/j.dental.2024.05.030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 03/15/2024] [Accepted: 05/29/2024] [Indexed: 06/10/2024]
Abstract
OBJECTIVES To investigate the flexural strength (FS), elastic modulus (E), Martens hardness (HM), water sorption (wsp), water solubility (wsl) and degree of conversion (DC) of 3D-printed, milled and injection molded splint materials. METHODS Specimens (N = 1140) were fabricated from five 3D-printed (GR-22 flex, GR-10 guide, ProArt Print Splint clear, V-Print Splint, V-Print Splint comfort), five milled (BioniCut, EldyPlus, ProArt CAD Splint clear, Temp Premium Flexible, Thermeo) and two injection molded (PalaXPress clear, Pro Base Cold) materials. FS, E, HM, wsp, wsl and DC were tested initially (24 h, 37 °C, H2O), after water storage (90 d, 37 °C, H2O) as well as after thermal cycling (5000 thermal cycles, 5/55 °C). Data were analyzed with Kolmogorov-Smirnov, Kruskal- Wallis, Mann-Whitney U test and Spearman's correlation (p < 0.05). RESULTS Initially, the mean flexural strength values ranged from 1.9 to 90.7 MPa for printed, 3.8 to 107 MPa for milled and 99.7 to 102 MPa for injection molded materials. The initial mean elastic modulus values were 0.0 to 2.4 GPa for printed, 0.1 to 2.7 GPa for milled and 2.8 GPa for injection molded materials. The initial mean Martens hardness values were 14.5 to 126 N/mm2 for printed, 50.2 to 171 N/mm2 for milled and 143 to 151 N/mm2 for injection molded materials. Initially, the mean water sorption values ranged from 23.1 to 41.2 μg/mm3 for printed, 4.5 to 23.5 μg/mm3 for milled and from 22.5 to 23.3 μg/ mm3 for injection molded materials. The initial mean water solubility values ranged from 2.2 to 7.1 μg/mm3 for printed, 0.0 to 0.5 μg/mm3 for milled and 0.1 to 0.3 μg/mm3 for injection molded materials. After water storage and thermal cycling most of the values decreased and some increased. The mean DC values ranged initially from 72.3 to 94.5 %, after water storage from 74.2 to 96.8 % and after thermal cycling from 75.6 to 95.4 % for the printed materials. SIGNIFICANCE The mechanical and physical properties of printed, milled and injection molded materials for occlusal devices vary and are influenced by aging processes. For clinical applications, materials need to be chosen according to the specific indications.
Collapse
Affiliation(s)
- Tina Maleki
- Department of Prosthetic Dentistry, University Hospital, LMU Munich, Munich, Germany.
| | - John Meinen
- Department of Prosthetic Dentistry, University Hospital, LMU Munich, Munich, Germany
| | - Andrea Coldea
- Department of Prosthetic Dentistry, University Hospital, LMU Munich, Munich, Germany
| | - Marcel Reymus
- Department of Conservative Dentistry and Peridontology, University Hospital, LMU Munich, Munich, Germany
| | - Daniel Edelhoff
- Department of Prosthetic Dentistry, University Hospital, LMU Munich, Munich, Germany
| | - Bogna Stawarczyk
- Department of Prosthetic Dentistry, University Hospital, LMU Munich, Munich, Germany
| |
Collapse
|
2
|
Kreitczick J, Schmohl L, Hahnel S, Vejjasilpa K, Schulz-Siegmund M, Koenig A. Aging processes in dental thermoplastics - Thermoanalytical investigations and effects on Vickers as well as Martens hardness. J Mech Behav Biomed Mater 2024; 154:106501. [PMID: 38531182 DOI: 10.1016/j.jmbbm.2024.106501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 02/21/2024] [Accepted: 03/08/2024] [Indexed: 03/28/2024]
Abstract
OBJECTIVE The influence of various aging protocols, representing and accelerating influences present in the dental context, on possible changes in the microstructure and mechanical properties of thermoplastics was investigated. In order to minimize the complexity of the systems, first pure polymers and then later the equivalent dental polymeric materials were analyzed. MATERIALS AND METHODS Pure polymers (Poly(methyl methacrylate) - PMMA, Polyoxymethylene homopolymer - POM-H, Polyether ether ketone - PEEK, Nylon 12 - PA12, Polypropylene - PP) were analyzed before as well as after applying different aging protocols relevant to the oral environment (ethanol, thermocycling, alkaline and acidic setting) by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The thermoanalytical parameters used were glass transition temperature (Tg), melting peak and crystallization peak temperature (Tpm, Tpc) and decomposition behavior. In a second step selected commercially available dental products (Telio CAD - PMMAD, Zirlux Acetal - POMD, Juvora Natural Dental Disc - PEEKD) aged by the protocol that previously showed strong effects were examined and additionally tested for changes in their Vickers and Martens hardness by Mann-Whitney-U test. RESULTS The combinations of pure polymers and viable aging protocols analyzed within this study were identified via TGA or DSC as PA12 & thermocycling, POM-H & denture cleanser/lactic acid/ethanol, PP & lactic acid. The dental polymeric materials PMMAD and POMD due to aging in lactic acid showed slight but significantly (p < 0.01) reduced Vickers and partly Martens hardness. PEEK showed the greatest material resistance within this study.
Collapse
Affiliation(s)
- Julia Kreitczick
- Department of Dental Prosthetics and Materials Science, Leipzig University, Liebigstraße 12, 04103, Leipzig, Germany
| | - Leonie Schmohl
- Department of Dental Prosthetics and Materials Science, Leipzig University, Liebigstraße 12, 04103, Leipzig, Germany.
| | - Sebastian Hahnel
- Department of Prosthetic Dentistry, UKR University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Germany
| | - Ketpat Vejjasilpa
- Institute of Pharmacy, Pharmaceutical Technology, Leipzig University, Eilenburger Str. 15a, 04317, Leipzig, Germany
| | - Michaela Schulz-Siegmund
- Institute of Pharmacy, Pharmaceutical Technology, Leipzig University, Eilenburger Str. 15a, 04317, Leipzig, Germany
| | - Andreas Koenig
- Department of Dental Prosthetics and Materials Science, Leipzig University, Liebigstraße 12, 04103, Leipzig, Germany
| |
Collapse
|
3
|
Chuchulska B, Dimitrova M, Vlahova A, Hristov I, Tomova Z, Kazakova R. Comparative Analysis of the Mechanical Properties and Biocompatibility between CAD/CAM and Conventional Polymers Applied in Prosthetic Dentistry. Polymers (Basel) 2024; 16:877. [PMID: 38611135 PMCID: PMC11013798 DOI: 10.3390/polym16070877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Revised: 03/14/2024] [Accepted: 03/19/2024] [Indexed: 04/14/2024] Open
Abstract
Modern media often portray CAD/CAM technology as widely utilized in the fabrication of dental prosthetics. This study presents a comparative analysis of the mechanical properties and biocompatibility of CAD/CAM (Computer-Aided Design/Computer-Aided Manufacturing) polymers and conventional polymers commonly utilized in prosthetic dentistry. With the increasing adoption of CAD/CAM technology in dental laboratories and practices, understanding the differences in material properties is crucial for informed decision-making in prosthodontic treatment planning. Through a narrative review of the literature and empirical data, this study evaluates the mechanical strength, durability, esthetics, and biocompatibility of CAD/CAM polymers in comparison to traditional polymers. Furthermore, it examines the implications of these findings on the clinical outcomes and long-term success of prosthetic restorations. The results provide valuable insights into the advantages and limitations of CAD/CAM polymers, informing clinicians and researchers about their suitability for various dental prosthetic applications. This study underscores the considerable advantages of CAD/CAM polymers over conventional ones in terms of mechanical properties, biocompatibility, and esthetics for prosthetic dentistry. CAD/CAM technology offers improved mechanical strength and durability, potentially enhancing the long-term performance of dental prosthetics, while the biocompatibility of these polymers makes them suitable for a broad patient demographic, reducing the risk of adverse reactions. The practical implications of these findings for dental technicians and dentists are significant, as understanding these material differences enables tailored treatment planning to meet individual patient needs and preferences. Integration of CAD/CAM technology into dental practices can lead to more predictable outcomes and heightened patient satisfaction with prosthetic restorations.
Collapse
Affiliation(s)
- Bozhana Chuchulska
- Department of Prosthetic Dentistry, Faculty of Dental Medicine, Medical University of Plovdiv, 4000 Plovdiv, Bulgaria; (A.V.); (I.H.); (Z.T.); (R.K.)
| | - Mariya Dimitrova
- Department of Prosthetic Dentistry, Faculty of Dental Medicine, Medical University of Plovdiv, 4000 Plovdiv, Bulgaria; (A.V.); (I.H.); (Z.T.); (R.K.)
| | - Angelina Vlahova
- Department of Prosthetic Dentistry, Faculty of Dental Medicine, Medical University of Plovdiv, 4000 Plovdiv, Bulgaria; (A.V.); (I.H.); (Z.T.); (R.K.)
- CAD/CAM Center of Dental Medicine, Research Institute, Medical University of Plovdiv, 4000 Plovdiv, Bulgaria
| | - Ilian Hristov
- Department of Prosthetic Dentistry, Faculty of Dental Medicine, Medical University of Plovdiv, 4000 Plovdiv, Bulgaria; (A.V.); (I.H.); (Z.T.); (R.K.)
| | - Zlatina Tomova
- Department of Prosthetic Dentistry, Faculty of Dental Medicine, Medical University of Plovdiv, 4000 Plovdiv, Bulgaria; (A.V.); (I.H.); (Z.T.); (R.K.)
| | - Rada Kazakova
- Department of Prosthetic Dentistry, Faculty of Dental Medicine, Medical University of Plovdiv, 4000 Plovdiv, Bulgaria; (A.V.); (I.H.); (Z.T.); (R.K.)
- CAD/CAM Center of Dental Medicine, Research Institute, Medical University of Plovdiv, 4000 Plovdiv, Bulgaria
| |
Collapse
|
4
|
R SA, Kalidasan Selvi B, Shankar SS, Hariharan A. Comparative Analysis of Strength of Differently Activated Denture Base Materials Including Recent Acetal Resin-Based Biodentaplast. Cureus 2024; 16:e54676. [PMID: 38524084 PMCID: PMC10960503 DOI: 10.7759/cureus.54676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/17/2024] [Indexed: 03/26/2024] Open
Abstract
AIM AND OBJECTIVES The aim of this study is to comparatively analyse the compressive and tensile strength of different types of record base materials made of different materials and processing techniques. MATERIALS AND METHODOLOGY The compressive and tensile strength of 4 types of injection moulded materials were compared with a control of conventional compression moulded material. Twenty test specimens (10 tensile and 10 compressive) were fabricated from each material. A test was done using the Instron 3382 (Norwood, MA, USA) universal testing machine. RESULTS Compressive and tensile test values showed significant differences between the record base resin groups tested for both compressive and tensile strength tests (p=0.00). The mean tensile strength value was greatest for Group V (66.0 MPa) and lowest for Group III (41.9MPa) and the mean compressive strength value was greatest for Group I (74.5 MPa) followed by Group V (70.2 MPa) and lowest for Group III (10.8 MPa). CONCLUSION Injection moulded acetal resin showed the highest tensile strength value; it was comparable to that of conventional compression moulded polymethyl methacrylate (PMMA). Compression moulding is reported to have the highest compressive strength values followed by injection moulded acetal resin material. Injection moulded acetal resin material attributed to its advantages and superior strength value, can be used as a material of choice in various clinical scenarios.
Collapse
Affiliation(s)
- Shakir Ahmed R
- Prosthodontics, Sri Ramachandra Institute of Higher Education and Research, Chennai, IND
| | | | | | | |
Collapse
|
5
|
Le Bars P, Bandiaky ON, Le Guéhennec L, Clouet R, Kouadio AA. Different Polymers for the Base of Removable Dentures? Part I: A Narrative Review of Mechanical and Physical Properties. Polymers (Basel) 2023; 15:3495. [PMID: 37688123 PMCID: PMC10490543 DOI: 10.3390/polym15173495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 08/14/2023] [Accepted: 08/17/2023] [Indexed: 09/10/2023] Open
Abstract
Even before considering their introduction into the mouth, the choice of materials for the optimization of the prosthesis depends on specific parameters such as their biocompatibility, solidity, resistance, and longevity. In the first part of this two-part review, we approach the various mechanical characteristics that affect this choice, which are closely related to the manufacturing process. Among the materials currently available, it is mainly polymers that are suitable for this use in this field. Historically, the most widely used polymer has been polymethyl methacrylate (PMMA), but more recently, polyamides (nylon) and polyether ether ketone (PEEK) have provided interesting advantages. The incorporation of certain molecules into these polymers will lead to modifications aimed at improving the mechanical properties of the prosthetic bases. In the second part of the review, the safety aspects of prostheses in the oral ecosystem (fragility of the undercuts of soft/hard tissues, neutral pH of saliva, and stability of the microbiota) are addressed. The microbial colonization of the prosthesis, in relation to the composition of the material used and its surface conditions (roughness, hydrophilicity), is of primary importance. Whatever the material and manufacturing process chosen, the coating or finishes dependent on the surface condition remain essential (polishing, non-stick coating) for limiting microbial colonization. The objective of this narrative review is to compile an inventory of the mechanical and physical properties as well as the clinical conditions likely to guide the choice between polymers for the base of removable prostheses.
Collapse
Affiliation(s)
- Pierre Le Bars
- Department of Prosthetic Dentistry, Faculty of Dentistry, Nantes University, 1 Place Alexis Ricordeau, 44042 Nantes, France; (L.L.G.); (R.C.); (A.A.K.)
- Oniris, CHU Nantes, INSERM, Regenerative Medicine and Skeleton, RMeS, Nantes Université, UMR 1229, 44000 Nantes, France;
| | - Octave Nadile Bandiaky
- Oniris, CHU Nantes, INSERM, Regenerative Medicine and Skeleton, RMeS, Nantes Université, UMR 1229, 44000 Nantes, France;
| | - Laurent Le Guéhennec
- Department of Prosthetic Dentistry, Faculty of Dentistry, Nantes University, 1 Place Alexis Ricordeau, 44042 Nantes, France; (L.L.G.); (R.C.); (A.A.K.)
- Oniris, CHU Nantes, INSERM, Regenerative Medicine and Skeleton, RMeS, Nantes Université, UMR 1229, 44000 Nantes, France;
| | - Roselyne Clouet
- Department of Prosthetic Dentistry, Faculty of Dentistry, Nantes University, 1 Place Alexis Ricordeau, 44042 Nantes, France; (L.L.G.); (R.C.); (A.A.K.)
- Oniris, CHU Nantes, INSERM, Regenerative Medicine and Skeleton, RMeS, Nantes Université, UMR 1229, 44000 Nantes, France;
| | - Alain Ayepa Kouadio
- Department of Prosthetic Dentistry, Faculty of Dentistry, Nantes University, 1 Place Alexis Ricordeau, 44042 Nantes, France; (L.L.G.); (R.C.); (A.A.K.)
- Department of Prosthetic Dentistry, Faculty of Dentistry, University Hospital Center, Abidjan P.O. Box 612, Côte d’Ivoire
| |
Collapse
|
6
|
Patil S, Licari FW, Bhandi S, Awan KH, Badnjević A, Belli V, Cervino G, Minervini G. The Cytotoxic Effect of Thermoplastic Denture Base Resins: A Systematic Review. J Funct Biomater 2023; 14:411. [PMID: 37623656 PMCID: PMC10455636 DOI: 10.3390/jfb14080411] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 07/06/2023] [Accepted: 07/14/2023] [Indexed: 08/26/2023] Open
Abstract
Partial or complete dentures are constructed from thermoplastic resins that are thermally processed and molded. This review examines the presently available evidence for the cytotoxicity of thermoplasticized denture base resins on human gingival epithelial cells, adipose cells, and fibroblasts; human amnion fibroblasts; and mouse fibroblasts. Electronic searches were performed on PubMed, Scopus, Web of Science, and Google Scholar databases to identify relevant articles to be included in the review until September 2022. Clinical, in vivo, and in vitro studies in English language were searched for. The quality of the studies was assessed using the Toxicological data Reliability Assessment tool (ToxRTool) developed by the European Commission's Joint Research Centre. GRADE assessment was used to evaluate the certainty of evidence. Seven in vitro studies were included in the review. The overall risk of bias was determined to be high, with the majority of studies assessed found to be reliable with restrictions or not reliable. Only two studies were considered reliable without restrictions based on ToxRTool assessment. The effect of thermoplastic denture base resins on viability and cell adherence of human gingival or amnion fibroblasts and mouse fibroblasts (L929s) is not significant. Conditioned media from unpolished specimens of resins were significantly more toxic to cultured cells than those from polished specimens. This may be of concern in cases of poor post-processing of dentures. Based on the limited evidence available, there is low-certainty evidence that thermoplastic denture base resins appear to be biocompatible and show insignificant cytotoxicity. Further well-designed trials adhering to standard reporting guidelines and using objective measures are necessary before outlining universal guidelines for best practice. Long-term in vivo and clinical assessment is necessary to corroborate laboratory findings with clinical outcomes. Denture base resins are in constant contact with oral tissues, and cytotoxic components released by the resins may irritate or inflame the tissues or provoke an allergic response.
Collapse
Affiliation(s)
- Shankargouda Patil
- College of Dental Medicine, Roseman University of Health Sciences, South Jordan, UT 84095, USA (S.B.)
| | - Frank W. Licari
- College of Dental Medicine, Roseman University of Health Sciences, South Jordan, UT 84095, USA (S.B.)
| | - Shilpa Bhandi
- College of Dental Medicine, Roseman University of Health Sciences, South Jordan, UT 84095, USA (S.B.)
| | - Kamran H. Awan
- College of Dental Medicine, Roseman University of Health Sciences, South Jordan, UT 84095, USA (S.B.)
| | - Almir Badnjević
- Verlab Research Institute for Biomedical Engineering, Medical Devices and Artificial Intelligence, 71000 Sarajevo, Bosnia and Herzegovina;
| | - Valentina Belli
- Department of Precision Medicine, Università degli Studi della Campania “Luigi Vanvitelli”, 80131 Naples, Italy
| | - Gabriele Cervino
- Department of Biomedical and Dental Sciences, Morphological and Functional Images, University of Messina, G. Martino Polyclinic, 98100 Messina, Italy
| | - Giuseppe Minervini
- Multidisciplinary Department of Medical-Surgical and Dental Specialties, University of Campania, Luigi Vanvitelli, 80138 Naples, Italy;
| |
Collapse
|
7
|
Zeidan AAEL, Sherif AF, Baraka Y, Abualsaud R, Abdelrahim RA, Gad MM, Helal MA. Evaluation of the Effect of Different Construction Techniques of CAD-CAM Milled, 3D-Printed, and Polyamide Denture Base Resins on Flexural Strength: An In Vitro Comparative Study. J Prosthodont 2023; 32:77-82. [PMID: 35343012 DOI: 10.1111/jopr.13514] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Accepted: 03/23/2022] [Indexed: 01/25/2023] Open
Abstract
PURPOSE To compare the flexural strength of computer-aided design and computer-aided manufacturing (CAD-CAM) milled denture base resin (DBR), 3D-printed DBR, polyamide, and conventional compression-molded DBR. MATERIALS AND METHODS Six denture base resins were used, one conventional heat-polymerized (Vertex), two milled CAD-CAM (AvaDent and Polident), two 3D-printed (Harz and NextDent), and one flexible polyamide (Polyamide). According to ISO 20795-1:2013, 60 specimens (65×10×3 mm) were constructed and divided into six groups (n = 10), according to DBR type. The flexural strength was measured using a universal testing machine and three-point loading test. Data were collected and analyzed using one-way ANOVA and Tukey's pair-wise post hoc tests (α = 0.05). RESULTS One-way ANOVA results showed significant differences in flexural strengths between the tested DBRs (p˂0.001). Milled denture base resins (AvaDent and Polident) had significantly higher flexural strength values than the other groups (p˂0.001) and were followed by Vertex and NextDent, while Polyamide and Harz had the lowest values. Polyamide and Harz denture base resins had significantly lower flexural strength values than conventional denture base resin (p˂0.001). CONCLUSION CAD-CAM milled DBRs showed the highest flexural strength when compared with conventional compression-molded or 3D-printed DBRs, while 3D-printed DBRs and polyamide showed the lowest flexural strengths.
Collapse
Affiliation(s)
- Ahmed Abd El-Latif Zeidan
- Department of Removable Prosthodontics, Faculty of Dental Medicine, Badr University, Badr City, Egypt
| | - Ahmed Fadlallah Sherif
- Department of Removable Prosthodontics, Faculty of Dental Medicine, Sinai University, North Sina, Egypt
| | - Yasser Baraka
- Department of Removable Prosthodontics, Faculty of Dental Medicine, Sinai University, North Sina, Egypt
| | - Reem Abualsaud
- Department of Substitutive Dental Sciences, College of Dentistry, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Ramy Abdallah Abdelrahim
- Department of Dental Biomaterials, Faculty of Dental Medicine, Al-Azhar University, Nasr City, Egypt
| | - Mohammed M Gad
- Department of Substitutive Dental Sciences, College of Dentistry, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Mohamed A Helal
- Department of Removable Prosthodontics, Faculty of Dental Medicine, Al-Azhar University, Nasr City, Egypt
| |
Collapse
|
8
|
Removable Partial Denture Frameworks in the Age of Digital Dentistry: A Review of the Literature. PROSTHESIS 2022. [DOI: 10.3390/prosthesis4020019] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Alloys of cobalt chromium have been used for decades to create frameworks for removable partial dentures. While cobalt chromium has multiple advantages, such as strength and light weight, the casting process is laborious and requires special care to ensure that human error is minimized. Furthermore, the display of metal clasps in these frameworks may be considered a limitation at times, especially with esthetically demanding patients. The introduction of digital technology to manufacturing in dentistry has brought forward new methods of fabricating cobalt chromium frameworks, some of which eliminate the casting process. Moreover, the development of high-performance polymers for use as removable partial denture frameworks brings multiple advantages, but raises concerns over design guidelines and principles. This review examines alternatives to conventionally cast frameworks so that clinicians may make evidence-based decisions when choosing framework materials and fabrication methods in the rapidly advancing world of digital dentistry.
Collapse
|
9
|
Air quality in a hospital dental department. J Dent Sci 2022; 17:1350-1355. [PMID: 35784142 PMCID: PMC9236934 DOI: 10.1016/j.jds.2022.03.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Revised: 03/23/2022] [Indexed: 11/24/2022] Open
Abstract
Background/purpose Documented studies demonstrated that particulate matter 2.5 (PM2.5) are relatively high in dental clinics. However, the PM2.5 composition is unclear. This study aimed to evaluate the dental department's air quality in a teaching hospital. Materials and methods The SKC AirChek XR5000 pumps and canister samplers were used to collect PM2.5 and volatile organic compounds (VOCs). The PM2.5 composition analysis (polycyclic aromatic hydrocarbons (PAHs) and metals) was conducted, and in the dental clinic and waiting room, the air quality comparison was investigated. Moreover, the dental clinic's air quality was compared before and after air purifier use. Results In the dental clinic and waiting room, the results revealed high PM2.5 concentration exceeding the standard of the United States Environmental Protection Agency (USEPA) (35 μg/m3); the values were 41.08–108.23 μg/m3 and 17.89–62.72 μg/m3, respectively. In both investigated locations, VOCs had no significant difference. Among 16 priority PAHs, the result indicated high level of benzo(b)fluoranthene (B(b)f), benzo(k)fluoranthene (B(k)f), benzo(a)pyrene (B(a)p), and indenopyrene (IP). B(b)f and B(k)f and lead (Pb) concentrations were detected with a significant difference in the clinic as compared to the waiting room. In addition, after air purifier use, the B(b)f concentration in the dental clinic reduced from 0.08 to 0.42 ug/m3 to 0.06–0.18 ug/m3 (P < 0.05). Conclusion For dental practitioners, an appropriated air quality regulation needs to be considered, due to high air pollutant concentration. In addition, using air purifier can efficiently reduce air pollutants.
Collapse
|
10
|
He W, Wang R, Guo F, Cao J, Guo Z, Qiang H, Liang S, Pang Q, Wei B. Preparation of Transparent Fast-Growing Poplar Veneers with a Superior Optical Performance, Excellent Mechanical Properties, and Thermal Insulation by Acetylation Modification Using a Green Catalyst. Polymers (Basel) 2022; 14:polym14020257. [PMID: 35054663 PMCID: PMC8779035 DOI: 10.3390/polym14020257] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 12/21/2021] [Accepted: 12/29/2021] [Indexed: 11/30/2022] Open
Abstract
There has been growing interest in transparent conductive substrates due to the prevailing flexible electron devices and the need for sustainable resources. In this study, we demonstrated a transparent fast-growing poplar veneers prepared by acetylated modification, followed by the infiltration of epoxy resin. The work mainly focused on the effect of acetylation treatment using a green catalyst of 4-Dimethylpyridine on the interface of the bulk fast-growing poplar veneer, and the result indicated that the interface hydrophobicity was greatly enhanced due to the higher substitute of acetyl groups; therefore, the interface compatibility between the cell wall and epoxy resin was improved. The obtained transparent fast-growing poplar veneers, hereafter referred to as TADPV, displayed a superior optical performance and flexibility, in which the light transmittance and haze were 90% and 70% at a wavelength of 550 nm, respectively, and the bending radius and bending angle parallel to grain of TADPV were 2 mm and 130°, respectively. Moreover, the tensile strength and tensile modulus of the TADPV were around 102 MPa and 198 MPa, respectively, which is significantly better than those of the plastic substrates used in flexible electron devices. At the same time, the thermal conductivity tests indicated that TADPV has a low coefficient of thermal conductivity of 0.34 Wm−1 K−1, which can completely meet the needs of transparent conductive substrates. Therefore, the obtained TADPV can be used as a candidate for a flexible transparent substrate of electron devices.
Collapse
Affiliation(s)
- Wen He
- College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, China; (R.W.); (F.G.); (J.C.); (Z.G.); (H.Q.); (S.L.); (Q.P.); (B.W.)
- Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing 210037, China
- Correspondence: ; Tel.: +86-138-0515-7249
| | - Rui Wang
- College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, China; (R.W.); (F.G.); (J.C.); (Z.G.); (H.Q.); (S.L.); (Q.P.); (B.W.)
| | - Feiyu Guo
- College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, China; (R.W.); (F.G.); (J.C.); (Z.G.); (H.Q.); (S.L.); (Q.P.); (B.W.)
| | - Jizhou Cao
- College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, China; (R.W.); (F.G.); (J.C.); (Z.G.); (H.Q.); (S.L.); (Q.P.); (B.W.)
| | - Zhihao Guo
- College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, China; (R.W.); (F.G.); (J.C.); (Z.G.); (H.Q.); (S.L.); (Q.P.); (B.W.)
| | - Han Qiang
- College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, China; (R.W.); (F.G.); (J.C.); (Z.G.); (H.Q.); (S.L.); (Q.P.); (B.W.)
| | - Shuang Liang
- College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, China; (R.W.); (F.G.); (J.C.); (Z.G.); (H.Q.); (S.L.); (Q.P.); (B.W.)
| | - Qunyan Pang
- College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, China; (R.W.); (F.G.); (J.C.); (Z.G.); (H.Q.); (S.L.); (Q.P.); (B.W.)
| | - Bairen Wei
- College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, China; (R.W.); (F.G.); (J.C.); (Z.G.); (H.Q.); (S.L.); (Q.P.); (B.W.)
| |
Collapse
|
11
|
GIBREEL M, PEREA-LOWERY L, VALLITTU PK, GAROUSHI S, LASSILA L. Two-body wear and surface hardness of occlusal splint materials. Dent Mater J 2022; 41:916-922. [DOI: 10.4012/dmj.2022-100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Mona GIBREEL
- Department of Biomaterials Science and Turku Clinical Biomaterials Centre-TCBC, Institute of Dentistry, University of Turku
| | - Leila PEREA-LOWERY
- Department of Biomaterials Science and Turku Clinical Biomaterials Centre-TCBC, Institute of Dentistry, University of Turku
| | | | - Sufyan GAROUSHI
- Department of Biomaterials Science and Turku Clinical Biomaterials Centre-TCBC, Institute of Dentistry, University of Turku
| | - Lippo LASSILA
- Department of Biomaterials Science and Turku Clinical Biomaterials Centre-TCBC, Institute of Dentistry, University of Turku
| |
Collapse
|
12
|
Gibreel M, Perea-Lowery L, Vallittu PK, Lassila L. Characterization of occlusal splint materials: CAD-CAM versus conventional resins. J Mech Behav Biomed Mater 2021; 124:104813. [PMID: 34530298 DOI: 10.1016/j.jmbbm.2021.104813] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 08/16/2021] [Accepted: 09/03/2021] [Indexed: 11/15/2022]
Abstract
AIM The aim of this in vitro study was to assess the mechanical properties of five commercially available subtractive computer-aided design and computer-aided manufacturing (CAD-CAM) milled splint materials, as well as to compare them with conventional heat-polymerized and autopolymerizing resins used in the construction of conventional splints. MATERIAL AND METHODS Five CAD-CAM milled (ProArt CAD Splint, Therapon Transpa, Temp Premium Flexible Transpa, Cast, and Aqua), one autopolymerizing (Palapress), and one heat-polymerized (Paladon 65) resin materials were evaluated. Flexural strength, E-modulus, Vickers hardness, fracture toughness, fracture work, water sorption, and water solubility were measured. Samples were evaluated after dry and water storage for 30 days at 37 °C. Data were collected and statistically analyzed. RESULTS Under both storage circumstances, the flexural strength values of Paladon 65, Therapon Transpa, Temp Premium Flexible Transpa, and Aqua were statistically non-significant (P=0.055). The polycarbonate-based CAD-CAM material Temp Premium Flexible Transpa had the highest statistically significant values of the fracture toughness and fracture work (P<0.001). Moreover, it exhibited the lowest percentages of water sorption and water solubility among the investigated materials (P<0.001). All of the CAD-CAM materials exhibited dry elastic moduli greater than Palapress and lower than Paladon 65. One of the CAD-CAM materials, Cast, had the highest dry Vickers hardness value, which was non-significant when compared to Therapon Transpa (P=0.762). CONCLUSION CAD-CAM polycarbonate-based splint materials exhibit higher fracture toughness and fracture work as well as lower water sorption and solubility than polymethyl methacrylate-based ones. The mechanical characteristics of the assessed CAD-CAM milled splint materials were not typically superior to those of the conventional heat-polymerized resin. However, some of them outperformed the autopolymerizing acrylic resin in terms of flexural strength, surface microhardness, water sorption, and water solubility.
Collapse
Affiliation(s)
- Mona Gibreel
- Department of Biomaterials Science and Turku Clinical Biomaterials Centre-TCBC, Institute of Dentistry, University of Turku, Turku, Finland.
| | - Leila Perea-Lowery
- Department of Biomaterials Science, Turku Clinical Biomaterials Centre-TCBC, Institute of Dentistry, University of Turku, Turku, Finland
| | - Pekka K Vallittu
- Professor and Chair of Biomaterials Science Department, University of Turku, Welfare Division, Turku, Finland
| | - Lippo Lassila
- Turku Clinical Biomaterials Centre-TCBC, Institute of Dentistry, University of Turku, Turku, Finland
| |
Collapse
|
13
|
Gad MM, Fouda SM, Abualsaud R, Alshahrani FA, Al-Thobity AM, Khan SQ, Akhtar S, Ateeq IS, Helal MA, Al-Harbi FA. Strength and Surface Properties of a 3D-Printed Denture Base Polymer. J Prosthodont 2021; 31:412-418. [PMID: 34347351 DOI: 10.1111/jopr.13413] [Citation(s) in RCA: 89] [Impact Index Per Article: 29.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/29/2021] [Indexed: 11/28/2022] Open
Abstract
PURPOSE This in vitro study evaluated the flexural strength, impact strength, hardness, and surface roughness of 3D-printed denture base resin subjected to thermal cycling treatment. MATERIALS AND METHODS According to ISO 20795-1:2013 standards, 120 acrylic resin specimens (40/flexural strength test, 40/impact strength, and 40/surface roughness and hardness test, n = 10) were fabricated and distributed into two groups: heat-polymerized; (Major.Base.20) as control and 3D-printed (NextDent) as experimental group. Half of the specimens of each group were subjected to 10,000 thermal cycles of 5 to 55°C simulating 1 year of clinical use. Flexural strength (MPa), impact strength (KJ/m2 ), hardness (VHN), and surface roughness (μm) were measured using universal testing machine, Charpy's impact tester, Vickers hardness tester, and profilometer, respectively. Data were analyzed by ANOVA and Tukey honestly significant difference (HSD) test (α = 0.05). RESULTS The values of flexural strength (MPa) were 86.63 ± 1.0 and 69.15 ± 0.88; impact strength (KJ/m2 )-6.32 ± 0.50 and 2.44 ± 0.31; hardness (VHN)-41.63 ± 2.03 and 34.62 ± 2.1; and surface roughness (μm)-0.18 ± 0.01 and 0.12 ± 0.02 for heat-polymerized and 3D-printed denture base materials, respectively. Significant differences in all tested properties were recorded between heat-polymerized and 3D-printed denture base materials (P < 0.001). Thermal cycling significantly lowered the flexural strength (63.93 ± 1.54 MPa), impact strength (2.40 ± 0.35 KJ/m2 ), and hardness (30.17 ± 1.38 VHN) of 3D-printed resin in comparison to thermal cycled heat-polymerized resin, but surface roughness showed non-significant difference (p = 0.262). CONCLUSION 3D-printed resin had inferior flexural strength, impact strength, and hardness values than heat-polymerized resin, but showed superior surface roughness. Temperature changes (thermal cycling) significantly reduced the hardness and flexural strength and increased surface roughness, but did not affect the impact strength.
Collapse
Affiliation(s)
- Mohammed M Gad
- Department of Substitutive Dental Sciences, College of Dentistry, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Shaimaa M Fouda
- Department of Substitutive Dental Sciences, College of Dentistry, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Reem Abualsaud
- Department of Substitutive Dental Sciences, College of Dentistry, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Faris A Alshahrani
- Department of Substitutive Dental Sciences, College of Dentistry, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Ahmad M Al-Thobity
- Department of Substitutive Dental Sciences, College of Dentistry, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Soban Q Khan
- Department of Dental Education, College of Dentistry, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Sultan Akhtar
- Department of Biophysics, Institute for Research and Medical Consultations (IRMC), Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Ijlal Shahrukh Ateeq
- Biomedical Engineering department, College of Engineering, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Mohamed A Helal
- Department of Removable Prosthodontics, Faculty of Dentistry, Al-Azhar University, Cairo, Egypt
| | - Fahad A Al-Harbi
- Department of Substitutive Dental Sciences, College of Dentistry, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| |
Collapse
|
14
|
Hao J, Murakami N, Yamazaki T, Iwasaki N, Yatabe M, Takahashi H, Wakabayashi N. Flexural and fatigue properties of polyester disk material for milled resin clasps. Dent Mater J 2021; 40:1359-1364. [PMID: 34234049 DOI: 10.4012/dmj.2021-037] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
To evaluate the flexural and fatigue properties of a polyester disk material used in milled resin clasps of removable partial dentures, experimental polyester disk (mPE), injection-molded polyester (iPE), and polymethyl methacrylate disk (mPMMA) were examined by three-point bending tests and cyclic fatigue tests at 0.75 or 1.50 mm deflection. The mPE exhibited significantly higher flexural strength than the iPE (p<0.05). Meanwhile, the mPMMA displayed higher flexural modulus and strength than the polyesters. The mPE exhibited a significantly lower residual strain than the iPE at the cyclic 0.75 mm deflection (p<0.05); however, microcracks were observed in the mPE at the 1.50 mm deflection. The mPMMA showed a high residual strain at the 0.75 mm deflection and fractured within 1,000 cycles at the 1.5 mm deflection. The higher flexural strength and lower residual strain of the mPE compared with the iPE suggest the advantages of milled resin clasps within a limited deflection.
Collapse
Affiliation(s)
- Jialin Hao
- Removable Partial Prosthodontics, Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| | - Natsuko Murakami
- Removable Partial Prosthodontics, Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| | - Toshiki Yamazaki
- Removable Partial Prosthodontics, Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| | - Naohiko Iwasaki
- Oral Biomaterial Development Engineering, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| | - Masaru Yatabe
- Removable Partial Prosthodontics, Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| | - Hidekazu Takahashi
- Oral Biomaterial Development Engineering, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| | - Noriyuki Wakabayashi
- Removable Partial Prosthodontics, Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| |
Collapse
|
15
|
Perea-Lowery L, Minja IK, Lassila L, Ramakrishnaiah R, Vallittu PK. Assessment of CAD-CAM polymers for digitally fabricated complete dentures. J Prosthet Dent 2021; 125:175-181. [DOI: 10.1016/j.prosdent.2019.12.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 12/11/2019] [Accepted: 12/11/2019] [Indexed: 10/25/2022]
|
16
|
Development of a Weight-Drop Impact Testing Method for Dental Applications. Polymers (Basel) 2020; 12:polym12122803. [PMID: 33256236 PMCID: PMC7760405 DOI: 10.3390/polym12122803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 11/22/2020] [Accepted: 11/23/2020] [Indexed: 11/26/2022] Open
Abstract
For evaluating the impact strength of dental materials, the Izod test or Charpy test has been used, but specimen preparation for these tests is difficult due to the adjustment of a notch on them. By contrast, a weight-drop impact test does not require notched specimens. Therefore, it might be possible to measure the impact strength more accurately than conventional methods. This study aimed to establish appropriate conditions for applying the weight-drop impact test on small specimens of acrylic resin. To determine the most reliable impact fracture energy of acrylic resins, different diameters and thicknesses of PMMA resin specimens, diameters and weights of the striker, and diameters of the supporting jig were compared. For all specimen thicknesses, when the striker diameter was 6–10 mm, the impact fracture energy was constant when the inner diameter of the specimen-supporting jig was 8–10 mm. In addition, the measured E50% value was mostly equal to the median value of the impact fracture energy. Thus, for the weight-drop impact test, this method was effective for material testing of small specimens, by clearly specifying the test conditions, such as the thickness of disc-shaped specimens, the diameter of the striker, and the inner diameter of the specimen-supporting jig.
Collapse
|
17
|
Mendoza-Carrasco I, Hotta J, Sugio CYC, Procópio ALF, Urban VM, Mosquim V, Foratori-Junior GA, Soares S, Neppelenbroek KH. Nonmetal clasp dentures: What is the evidence about their use? J Indian Prosthodont Soc 2020; 20:278-284. [PMID: 33223697 PMCID: PMC7654199 DOI: 10.4103/jips.jips_459_19] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2019] [Revised: 04/27/2020] [Accepted: 06/04/2020] [Indexed: 11/21/2022] Open
Abstract
The aim was to discuss the indications, contraindications, advantages, and disadvantages of Nonmetal clasp dentures (NMCDs), as well as the most relevant properties of its constituent materials. A search was conducted using the keywords: “nonmetal clasp dentures,” “thermoplastic resin,” “flexible resin removable partial denture,” “polyamide,” and “nylon” in databases PubMed/Medline, Lilacs, SciELO, and textbooks between 1955 and 2020. Theses and texts without reliable sources of publication were excluded. Once the analysis instruments were determined, the data were analyzed and discussed. NMCDs present high flexibility, easy adaptation to the abutments, color compatibility and biocompatibility with the oral mucosa, and absence of visible metal clasps. However, they need laboratory relining, grinding, and polishing, do not have criteria for its planning, become rougher and stained over time, and are able to traumatize supporting tissues. The association with metal components seems to be an alternative to increase the success of NMCDs by combining esthetics and biomechanical principles of conventional removable partial dentures. The lack of long-term clinical studies makes the professionals to rely solely on previous experiences or on the manufacturers' recommendations. It suggested that NMCDs must be indicated with caution when not used temporarily.
Collapse
Affiliation(s)
- Inti Mendoza-Carrasco
- Department of Prosthodontics and Periodontics, Bauru School of Dentistry, University of São Paulo, Bauru, São Paulo, Brazil
| | - Juliana Hotta
- Department of Prosthodontics and Periodontics, Bauru School of Dentistry, University of São Paulo, Bauru, São Paulo, Brazil
| | - Carolina Yoshi Campos Sugio
- Department of Prosthodontics and Periodontics, Bauru School of Dentistry, University of São Paulo, Bauru, São Paulo, Brazil
| | - Andréa Lemos Falcao Procópio
- Department of Prosthodontics and Periodontics, Bauru School of Dentistry, University of São Paulo, Bauru, São Paulo, Brazil
| | | | - Victor Mosquim
- Department of Operative Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo, Bauru, São Paulo, Brazil
| | - Gerson Aparecido Foratori-Junior
- Department of Pediatric Dentistry, Orthodontics and Public Health, Bauru School of Dentistry, University of São Paulo, Bauru, São Paulo, Brazil
| | - Simone Soares
- Department of Prosthodontics and Periodontics, Bauru School of Dentistry, University of São Paulo, Bauru, São Paulo, Brazil
| | - Karin Hermana Neppelenbroek
- Department of Prosthodontics and Periodontics, Bauru School of Dentistry, University of São Paulo, Bauru, São Paulo, Brazil
| |
Collapse
|
18
|
Prpić V, Schauperl Z, Ćatić A, Dulčić N, Čimić S. Comparison of Mechanical Properties of 3D‐Printed, CAD/CAM, and Conventional Denture Base Materials. J Prosthodont 2020; 29:524-528. [DOI: 10.1111/jopr.13175] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/03/2020] [Indexed: 11/28/2022] Open
Affiliation(s)
- Vladimir Prpić
- PhD Student, School of Dental MedicineUniversity of Zagreb Zagreb Croatia
| | - Zdravko Schauperl
- Full Professor, Department of Materials, Faculty of Mechanical Engineering and Naval ArchitectureUniversity of Zagreb Zagreb Croatia
| | - Amir Ćatić
- Full Professor, Department of Prosthodontics, School of Dental MedicineUniversity of Zagreb Zagreb Croatia
| | - Nikša Dulčić
- Associate Professor, Department of Prosthodontics, School of Dental MedicineUniversity of Zagreb Zagreb Croatia
| | - Samir Čimić
- Assistant Professor, Department of Prosthodontics, School of Dental MedicineUniversity of Zagreb Zagreb Croatia
| |
Collapse
|
19
|
Gligorijević N, Igić M, Kostić M, Pejčić A. Properties and applications of dental polyamides. ACTA STOMATOLOGICA NAISSI 2020. [DOI: 10.5937/asn2082098g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
Abstract
Introduction: By examining numerous thermoplastic and flexible materials that would aesthetically and functionally surpass acrylates used for the production of dental prostheses, polyamides were discovered as materials with great potential application in prosthodontics. The aim of this study was to describe polyamide materials used for the production of partial dentures. Material and methods: The main methodological approach of this study was a systematic search of the literature in two electronic databases: Google Scholar and PubMed using predefined keyword combinations. Results: The advantage of polyamide dentures is the comfort and ease of accommodation of the patient, with preserved optimal mechanical and physical properties. The dentures are flexible but rigid enough to be resistant to shock and fractures. Due to their low specific weight, polyamide dentures are light, extremely thin and do not interrupt patient speech. Excellent aesthetics are provided by a high choice of working colors and high translucency of the material, which ensures that the soft tissue that's covered by the denture base or clasp is seen through the prosthesis and gives it a more natural appearance in the patient's mouth. Conslusion: Polyamides, unlike acrylates, do not contain residual monomers, so they have an greater degree of biocompatibility. They can be used for the production of both complete and partial dentures, in combination with a Cr-Co skeleton, or crowns and bridges.
Collapse
|
20
|
Hada T, Suzuki T, Minakuchi S, Takahashi H. Reduction in maxillary complete denture deformation using framework material made by computer-aided design and manufacturing systems. J Mech Behav Biomed Mater 2019; 103:103514. [PMID: 31778908 DOI: 10.1016/j.jmbbm.2019.103514] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2019] [Revised: 10/29/2019] [Accepted: 10/30/2019] [Indexed: 11/19/2022]
Abstract
The aim of this study was to investigate the effects of framework materials manufactured by dental CAD/CAM systems on complete denture deformation. Four materials were used for the maxillary complete denture framework: fiber-reinforced composite (FRC), nano-zirconia (N-Zr), cobalt-chromium-molybdenum alloy (CCM), and polyether-ether-ketone (PEEK). The framework materials were prepared using CAD/CAM systems. Six dentures of each material were fabricated, using polymethyl-methacrylate (PMMA) as a control. The thickness of the palatal area was 1.0 mm for PMMA and PEEK and 0.5 mm for FRC, N-Zr, and CCM. The denture deformation during occlusal load was monitored using four rosette strain gauges placed on the midline of the denture. The maximum principal strain (MPS) of each gauge, except that at the labial frenum, increased proportionally with increasing applied load. The directions of MPS were predominantly perpendicular to the midline of the denture. When a 200-N load was applied, the MPS at the incisive papilla in N-Zr and CCM was half that of PMMA; there was no significant difference among MPSs of PEEK, PMMA and FRC. The MPS at the end point of the denture in FRC, N-Zr, and CCM was significantly smaller than that of PMMA. The MPSs of the complete denture decreased when the CAD/CAM fabricated framework was used. The effects of the CAD/CAM fabricated framework on complete denture deformation varied due to the material used; however, a CAD/CAM fabricated framework material is considered to be effective for reducing complete denture deformation.
Collapse
Affiliation(s)
- Tamaki Hada
- Department of Gerodontology and Oral Rehabilitation, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan
| | - Tetsuya Suzuki
- Department of Oral Prosthetic Engineering, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan
| | - Shunsuke Minakuchi
- Department of Gerodontology and Oral Rehabilitation, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan
| | - Hidekazu Takahashi
- Department of Oral Biomaterials Development Engineering, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan.
| |
Collapse
|
21
|
Manzon L, Fratto G, Poli O, Infusino E. Patient and Clinical Evaluation of Traditional Metal and Polyamide Removable Partial Dentures in an Elderly Cohort. J Prosthodont 2019; 28:868-875. [DOI: 10.1111/jopr.13102] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/30/2019] [Indexed: 11/27/2022] Open
|
22
|
A study of the flexural strength and surface hardness of different materials and technologies for occlusal device fabrication. J Prosthet Dent 2019; 121:955-959. [DOI: 10.1016/j.prosdent.2018.09.022] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Revised: 09/24/2018] [Accepted: 09/24/2018] [Indexed: 11/24/2022]
|
23
|
Song SY, Kim KS, Lee JY, Shin SW. Physical properties and color stability of injection-molded thermoplastic denture base resins. J Adv Prosthodont 2019; 11:32-40. [PMID: 30847047 PMCID: PMC6400709 DOI: 10.4047/jap.2019.11.1.32] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 12/03/2018] [Accepted: 01/21/2019] [Indexed: 11/12/2022] Open
Abstract
PURPOSE The purpose of this study was to compare mechanical and physical properties of injection-molded thermoplastic denture base resins. MATERIALS AND METHODS In this study, six commercially available products (VA; Valplast, LC; Lucitone, ST; Smiltone, ES; Estheshot-Bright, AC; Acrytone, WE; Weldenz) were selected from four types of thermoplastic denture base materials (Polyamide, Polyester, Acrylic resin and Polypropylene). The flexural properties and shore D hardness have been investigated and water sorption and solubility, and color stability have evaluated. RESULTS For the flexural modulus value, ES showed the highest value and WE showed significantly lower value than all other groups (P<.05). Most of experimental groups showed weak color stability beyond the clinically acceptable range. CONCLUSION Within the limits of this study, thermoplastic denture base resin did not show sufficient modulus to function as a denture base. In addition, all resins showed discoloration with clinical significance, and especially polyamides showed the lowest color stability.
Collapse
Affiliation(s)
- So-Yeon Song
- Department of Biomedical Science, Graduate School of Korea University, Seoul, Republic of Korea.,Institute for Clinical Dental Research, Korea University Medical Center, Republic of Korea
| | - Kyoung-Soo Kim
- Department of Medicine, Graduate School of Korea University, Seoul, Republic of Korea
| | - Jeong-Yol Lee
- Department of Advanced Prosthodontics, Korea University Guro Hospital, Seoul, Republic of Korea
| | - Sang-Wan Shin
- Doctor of Medicine, Korea University, Seoul, Republic of Korea
| |
Collapse
|
24
|
Yamazaki T, Murakami N, Suzuki S, Handa K, Yatabe M, Takahashi H, Wakabayashi N. Influence of block-out on retentive force of thermoplastic resin clasps: an in vitro experimental and finite element analysis. J Prosthodont Res 2019; 63:303-308. [PMID: 30704930 DOI: 10.1016/j.jpor.2019.01.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 01/01/2019] [Accepted: 01/08/2019] [Indexed: 10/27/2022]
Abstract
PURPOSE The purpose of this study was to determine the effect of block-out preparation, used to eliminate the undercut area, on the retentive force and stress distribution of resin clasps. METHODS A total of 72 polyester and polyamide resin clasps were fabricated on a premolar abutment crown following six block-out preparations. A combination of two types of vertical block-outs and three types of horizontal block-outs (on the missing side) was used on the abutment tooth. Each clasp was subjected to an in vitro removal test using a universal testing machine. The retentive force and traces of the clasp on the abutment tooth were recorded and analyzed with one-way analysis of variance and post hoc comparisons (α=0.05). Non-linear finite element analysis was performed to assess the stress distributions of the resin clasps. RESULTS Resin clasps with a vertical block-out of 0.75mm undercut showed significantly higher retentive force than those with the 0.5mm undercut. Resin clasps with horizontal block-out showed significantly lower retentive force than those without horizontal block-out. There was no significant difference between the two thermoplastic resins. The maximum first principal stress of the resin clasp was concentrated under the shoulder of the clasp and strongly influenced by the width of horizontal block-out in the finite element analysis. CONCLUSIONS This in vitro experiment suggested that a horizontal block-out is necessary even for a 0.5-mm undercut. The design of the resin clasp should be considered from two aspects: retentive force and deformation risk.
Collapse
Affiliation(s)
- Toshiki Yamazaki
- Removable Partial Prosthodontics, Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Natsuko Murakami
- Removable Partial Prosthodontics, Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan.
| | - Shizuka Suzuki
- Removable Partial Prosthodontics, Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Kazuyuki Handa
- Removable Partial Prosthodontics, Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Masaru Yatabe
- Removable Partial Prosthodontics, Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Hidekazu Takahashi
- Oral Biomaterials Development Engineering, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Noriyuki Wakabayashi
- Removable Partial Prosthodontics, Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| |
Collapse
|
25
|
Sun Y, Song SY, Lee KS, Park JH, Ryu JJ, Lee JY. Effects of relining materials on the flexural strength of relined thermoplastic denture base resins. J Adv Prosthodont 2018; 10:361-366. [PMID: 30370027 PMCID: PMC6202434 DOI: 10.4047/jap.2018.10.5.361] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Revised: 07/05/2018] [Accepted: 08/22/2018] [Indexed: 01/17/2023] Open
Abstract
PURPOSE The aim of this study was to evaluate the effects of relining materials on the flexural strength of relined thermoplastic denture base resins (TDBRs). MATERIALS AND METHODS For shear bond strength testing, 120 specimens were fabricated using four TDBRs (EstheShot-Bright, Acrytone, Valplast, Weldenz) that were bonded with three autopolymerizing denture relining resins (ADRRs: Vertex Self-Curing, Tokuyama Rebase, Ufi Gel Hard) with a bond area of 6.0 mm in diameter and were assigned to each group (n=10). For flexural strength testing, 120 specimens measuring 64.0×10.0×3.3 mm (ISO-1567:1999) were fabricated using four TDBRs and three ADRRs and were assigned to each group (n=10). The thickness of the specimens measured 2.0 mm of TDBR and 1.3 mm of ADRR. Forty specimens using four TDBRs and 30 specimens using ADRRs served as the control. All specimens were tested on a universal testing machine. For statistical analysis, Analysis of variance (ANOVA) with Tukey's test as post hoc and Spearman's correlation coefficient analysis (P=.05) were performed. RESULTS Acry-Tone showed the highest shear bond strength, while Weldenz demonstrated the lowest bond strength between TDBR and ADRRs compared to other groups. EstheShot-Bright exhibited the highest flexural strength, while Weldenz showed the lowest flexural strength. Relined EstheShot-Bright demonstrated the highest flexural strength and relined Weldenz exhibited the lowest flexural strength (P<.05). Flexural strength of TDBRs (P=.001) and shear bond strength (P=.013) exhibited a positive correlation with the flexural strength of relined TDBRs. CONCLUSION The flexural strength of relined TDBRs was affected by the flexural strength of the original denture base resins and bond strength between denture base resins and relining materials.
Collapse
Affiliation(s)
- Yunhan Sun
- Department of Medicine, Graduate School, Korea University, Seoul, Republic of Korea
| | - So-Yeon Song
- Department of Biomedical Sciences, Graduate School, Korea University, Seoul, Republic of Korea
| | - Ki-Sun Lee
- Department of Prosthodontics, Korea University Guro Hospital, Seoul, Republic of Korea
| | - Jin-Hong Park
- Department of Prosthodontics, Korea University Guro Hospital, Seoul, Republic of Korea
| | - Jae-Jun Ryu
- Department of Prosthodontics, Korea University Guro Hospital, Seoul, Republic of Korea
| | - Jeong-Yol Lee
- Department of Prosthodontics, Korea University Guro Hospital, Seoul, Republic of Korea
| |
Collapse
|
26
|
Lee HH, Lee JH, Yang TH, Kim YJ, Kim SC, Kim GR, Kim HR, Lee CJ, Okubo C. Evaluation of the flexural mechanical properties of various thermoplastic denture base polymers. Dent Mater J 2018. [PMID: 29515045 DOI: 10.4012/dmj.2017-373] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
This study evaluated the flexural mechanical properties of various thermoplastic denture base polymers (six polyamides, four acrylic resins, polyester, polypropylene, and polycarbonate) by three different testing conditions; specimens were tested in water bath at 37°C (Wet/Water, by ISO 20795-1), or in ambient air (Wet/Air) after being immersed in distilled water for 50 h, or after desiccation for 7 days (Dry/Air). The mean ultimate flexural strength (UFS) and flexural modulus (FM) for most products ranged from 27 to 61 MPa and from 611 to 1,783 MPa respectively, which failed to meet the minimum requirements of the international standard, except for polycarbonate (89 and 2,245 MPa). The mean UFS and FM values were ranked Dry/Air>Wet/Air>Wet/Water (p<0.05). In conclusion, the flexural mechanical properties of denture base polymers varied with the products and were significantly affected by the testing medium (air or water) and specimen conditions (wet or dry).
Collapse
Affiliation(s)
- Hae-Hyoung Lee
- Department of Biomaterials Science, College of Dentistry, Dankook University.,Institute of Tissue Regeneration Engineering, Dankook University
| | - Jung-Hwan Lee
- Institute of Tissue Regeneration Engineering, Dankook University
| | - Tae-Hyun Yang
- Department of Biomaterials Science, College of Dentistry, Dankook University
| | - Yu-Jin Kim
- Department of Biomaterials Science, College of Dentistry, Dankook University
| | - Si-Chul Kim
- Department of Dental Technology, Chungbuk Health & Science University
| | - Gyu-Ri Kim
- Department of Dental Laboratory, Gimcheon University
| | - Hyung-Rae Kim
- Department of Biomaterials Science, College of Dentistry, Dankook University
| | | | - Chikahiro Okubo
- Department of Removable Prosthodontics, School of Dental Medicine, Tsurumi University
| |
Collapse
|
27
|
Volumetric Change as a Parameter for the Accuracy of Impression Materials. JOURNAL OF BIOMIMETICS BIOMATERIALS AND BIOMEDICAL ENGINEERING 2018. [DOI: 10.4028/www.scientific.net/jbbbe.36.17] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this paper we studied the behavior of some impression materials such as alginate, condensation and addition silicones, considering the following parameters: the reproductive capacity of morphological details - dimensional stability - the ability to reproduce with accuracy the ratio between morphological elements. The essential conditions that an impression material should fulfill are plasticity, fidelity, flexibility, good mechanical strength, dimensional stability, suitable setting time and compatibility with materials from which the models are manufactured.The study results indicated that condensation silicones present the highest volumetric changes, their contraction being the result of the evaporation of volatile byproducts.The dimensional stability of fingerprint materials is one of the variables that contribute to the accuracy or inaccuracy of dental prostheses, other factors being represented by the changes occurring during the preparation of the fingerprint material as well as the fingerprinting techniques.
Collapse
|
28
|
Hamanaka I, Isshi K, Takahashi Y. Fabrication of a nonmetal clasp denture supported by an intraoral scanner and CAD-CAM. J Prosthet Dent 2017; 120:9-12. [PMID: 29258692 DOI: 10.1016/j.prosdent.2017.09.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Revised: 09/09/2017] [Accepted: 09/13/2017] [Indexed: 10/18/2022]
Abstract
This clinical report describes the management of a patient who had a metal allergy and had difficulty sitting in a dental chair for an extended period. The presented treatment used an intraoral scanner and computer-aided design and computer-aided manufacturing (CAD-CAM) to fabricate a nonmetal clasp denture. The described procedure may reduce patient discomfort and chair-time.
Collapse
Affiliation(s)
- Ippei Hamanaka
- Research Associate, Division of Removable Prosthodontics, Fukuoka Dental College, Fukuoka, Japan.
| | - Kota Isshi
- Dental Technician, Central Dental Laboratory, Fukuoka Dental College Hospital, Fukuoka, Japan
| | - Yutaka Takahashi
- Professor, Division of Removable Prosthodontics, Fukuoka Dental College, Fukuoka, Japan
| |
Collapse
|
29
|
Polychronakis N, Sarafianou A, Zissis A, Papadopoulos T. The Influence of Thermocycling on the Flexural Strength of a Polyamide Denture Base Material. Acta Stomatol Croat 2017; 51:309-315. [PMID: 29872236 PMCID: PMC5975457 DOI: 10.15644/asc51/4/5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Objective The aim of the present study was to evaluate the influence of thermocycling on the flexural strength of a polyamide base denture material. Materials and methods A polyamide denture base material (Valplast) was tested, whereas a PMMA material (Vertex) was used as a control. Thirty specimens of each material were fabricated for flexural strength testing according to ISO 1567. They were prepared and stored in water at 37°C for 48 hours. The specimens of each material were divided into three equal groups (n=10). Flexural strength testing was performed immediately after water storage and after thermocycling (5°C / 55°C, 2 c/min) for 3000 and 5000 cycles. A three point flexural test was performed on a universal testing machine at a crosshead speed of 5 mm/min. The final flexural strength was calculated using the formula: FS = 3 PL/2 bd2. A two-way ANOVA with post-hoc analysis using Tukey's procedure was applied at .05 level of statistical significance. Results A statistically significant reduction in flexural strength was recorded after thermocycling at 3000 cycles for PMMA and at 5000 cycles for both materials. The flexural strength of PMMA was significantly higher compared to polyamide for all the conditions tested (p<0.05). Conclusion Thermocycling had a significant adverse effect on the flexural strength of polyamide and PMMA denture base materials.
Collapse
Affiliation(s)
- Nick Polychronakis
- Removable Prosthodontics, Dental School, National and Kapodistrian University of Athens, Greece
| | - Aspasia Sarafianou
- Department of Prosthodontics, Dental School, National and Kapodistrian University of Athens, Greece
| | - Alcibiadis Zissis
- Removable Prosthodontics, Dental School, National and Kapodistrian University of Athens, Greece
| | | |
Collapse
|
30
|
Lee JH, Jun SK, Kim SC, Okubo C, Lee HH. Investigation of the cytotoxicity of thermoplastic denture base resins. J Adv Prosthodont 2017; 9:453-462. [PMID: 29279765 PMCID: PMC5741449 DOI: 10.4047/jap.2017.9.6.453] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2016] [Revised: 03/08/2017] [Accepted: 08/20/2017] [Indexed: 11/08/2022] Open
Abstract
PURPOSE The purpose of this study was to investigate the in vitro cytotoxicity of thermoplastic denture base resins and to identify the possible adverse effects of these resins on oral keratinocytes in response to hot water/food intake. MATERIALS AND METHODS Six dental thermoplastic resin materials were evaluated: three polyamide materials (Smile tone, ST; Valplast, VP; and Luciton FRS, LF), two acrylic materials (Acrytone, AT; and Acryshot, AS), and one polypropylene resin material (Unigum, UG). One heat-polymerized acrylic resin (Vertex RS, RS) was chosen for comparison. After obtaining extracts from specimens of the denture resin materials (Φ=10 mm and d=2 mm) under different extraction conditions (37℃ for 24 hours, 70℃ for 24 hours, and 121℃ for 1 hour), the extracts (50%) or serial dilutions (25%, 12.5%, and 6.25%) in distilled water were co-cultured for 24 hours with immortalized human oral keratinocytes (IHOKs) or mouse fibroblasts (L929s) for the cytotoxicity assay described in ISO 10993. RESULTS Greater than 70% viability was detected under all test conditions. Significantly lower IHOK and L929 viability was detected in the 50% extract from the VP (70℃) and AT (121℃) samples (P<.05), but only L929 showed reduced viability in the 50% and 25% extract from LF (37℃) (P<.05). CONCLUSION Extracts obtained from six materials under different extraction conditions (37℃, 70℃, and 121℃) did not exhibit severe cytotoxicity (less than 70% viability), although their potential risk to oral mucosa at high temperatures should not be ignored.
Collapse
Affiliation(s)
- Jung-Hwan Lee
- Institute of Tissue Regeneration Engineering (ITREN), Dankook University, Cheonan, Republic of Korea
| | - Soo-Kyung Jun
- Institute of Tissue Regeneration Engineering (ITREN), Dankook University, Cheonan, Republic of Korea.,Department of Biomaterials Science, College of Dentistry, Dankook University, Cheonan, Republic of Korea
| | - Si-Chul Kim
- Department of Biomaterials Science, College of Dentistry, Dankook University, Cheonan, Republic of Korea
| | - Chikahiro Okubo
- Department of Removable Prosthodontics, Tsurumi University School of Dental Medicine, Tsurumi-ku, Yokohama-shi, Japan
| | - Hae-Hyoung Lee
- Institute of Tissue Regeneration Engineering (ITREN), Dankook University, Cheonan, Republic of Korea.,Department of Biomaterials Science, College of Dentistry, Dankook University, Cheonan, Republic of Korea
| |
Collapse
|
31
|
Nagakura M, Tanimoto Y, Nishiyama N. Effect of fiber content on flexural properties of glass fiber-reinforced polyamide-6 prepared by injection molding. Dent Mater J 2017; 36:415-421. [PMID: 28190814 DOI: 10.4012/dmj.2016-252] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The use of non-metal clasp denture (NMCD) materials may seriously affect the remaining tissues because of the low rigidity of NMCD materials such as polyamides. The purpose of this study was to develop a high-rigidity glass fiber-reinforced thermoplastic (GFRTP) composed of E-glass fiber and polyamide-6 for NMCDs using an injection molding. The reinforcing effects of fiber on the flexural properties of GFRTPs were investigated using glass fiber content ranging from 0 to 50 mass%. Three-point bending tests indicated that the flexural strength and elastic modulus of a GFRTP with a fiber content of 50 mass% were 5.4 and 4.7 times higher than those of unreinforced polyamide-6, respectively. The result showed that the physical characteristics of GFRTPs were greatly improved by increasing the fiber content, and the beneficial effects of fiber reinforcement were evident. The findings suggest that the injection-molded GFRTPs are adaptable to NMCDs because of their excellent mechanical properties.
Collapse
Affiliation(s)
- Manamu Nagakura
- Department of Dental Biomaterials, Nihon University School of Dentistry at Matsudo
| | - Yasuhiro Tanimoto
- Department of Dental Biomaterials, Nihon University School of Dentistry at Matsudo
| | - Norihiro Nishiyama
- Department of Dental Biomaterials, Nihon University School of Dentistry at Matsudo
| |
Collapse
|
32
|
Nguyen LG, Kopperud HM, Øilo M. Water sorption and solubility of polyamide denture base materials. ACTA BIOMATERIALIA ODONTOLOGICA SCANDINAVICA 2017. [PMID: 28642931 PMCID: PMC5463346 DOI: 10.1080/23337931.2017.1326009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Purpose: Some patients experience adverse reactions to poly(methyl methacrylate)-based (PMMA) dentures. Polyamide (PA) as an alternative to PMMA has, however, not been well documented with regard to water sorption and water solubility. The aim of this in vitro study was to measure water sorption and water solubility of two PA materials compared with PMMA, and to evaluate the major components released from the PA materials and the effect on hardness of the materials. Methods: Ten discs (40.0 mm diameter, 2.0 mm thick) of each material (PA: Valplast and Breflex; PMMA: SR Ivocap HIP) were prepared according to manufacturers' recommendations. The specimens were tested for water sorption and water solubility, according to a modification of ISO 20795-1:2008. Released substances were analysed by gas chromatography/mass spectrometry (GC/MS). Results: There were statistically significant differences among the materials regarding water sorption, water solubility and time to water saturation. Breflex had the highest water sorption (30.4 μg/mm3), followed by PMMA-material (25.8 μg/mm3) and Valplast (13.6 μg/mm3). Both PA materials had statistically significant lower water solubility than the PMMA. Both PA had a net increase in weight. Analysis by GC/MS identified release of the compound 12-aminododecanolactam from the material Valplast. No release was found from the Breflex material. Conclusions: The PA denture materials show differences in water sorption and solubility, but within the limits of the standard requirements. The PA showed a net increase in weight after long-term water sorption. The clinical implications of the findings are not elucidated.
Collapse
Affiliation(s)
- Long G Nguyen
- Department of Clinical Dentistry, Faculty of Medicine and Dentistry, University of BergenBergenNorway
| | | | - Marit Øilo
- Department of Clinical Dentistry, Faculty of Medicine and Dentistry, University of BergenBergenNorway
| |
Collapse
|
33
|
Nasution H, Kamonkhantikul K, Arksornnukit M, Takahashi H. Pressure transmission area and maximum pressure transmission of different thermoplastic resin denture base materials under impact load. J Prosthodont Res 2017; 62:44-49. [PMID: 28606420 DOI: 10.1016/j.jpor.2017.05.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 05/02/2017] [Accepted: 05/18/2017] [Indexed: 11/18/2022]
Abstract
PURPOSES The purposes of the present study were to examine the pressure transmission area and maximum pressure transmission of thermoplastic resin denture base materials under an impact load, and to evaluate the modulus of elasticity and nanohardness of thermoplastic resin denture base. METHODS Three injection-molded thermoplastic resin denture base materials [polycarbonate (Basis PC), ethylene propylene (Duraflex), and polyamide (Valplast)] and one conventional heat-polymerized acrylic resin (PMMA, SR Triplex Hot) denture base, all with a mandibular first molar acrylic resin denture tooth set in were evaluated (n=6). Pressure transmission area and maximum pressure transmission of the specimens under an impact load were observed by using pressure-sensitive sheets. The modulus of elasticity and nanohardness of each denture base (n=10) were measured on 15×15×15×3mm3 specimen by using an ultramicroindentation system. The pressure transmission area, modulus of elasticity, and nanohardness data were statistically analyzed with 1-way ANOVA, followed by Tamhane or Tukey HSD post hoc test (α=.05). The maximum pressure transmission data were statistically analyzed with Kruskal-Wallis H test, followed by Mann-Whitney U test (α=.05). RESULTS Polymethyl methacrylate showed significantly larger pressure transmission area and higher maximum pressure transmission than the other groups (P<.001). Significant differences were found in modulus of elasticity and nanohardness among the four types of denture bases (P<.001). CONCLUSIONS Pressure transmission area and maximum pressure transmission varied among the thermoplastic resin denture base materials. Differences in the modulus of elasticity and nanohardness of each type of denture base were demonstrated.
Collapse
Affiliation(s)
- Hubban Nasution
- Department of Prosthodontics, Faculty of Dentistry, Chulalongkorn University, Bangkok, Thailand
| | - Krid Kamonkhantikul
- Department of Prosthodontics, Faculty of Dentistry, Chulalongkorn University, Bangkok, Thailand
| | - Mansuang Arksornnukit
- Department of Prosthodontics, Faculty of Dentistry, Chulalongkorn University, Bangkok, Thailand.
| | - Hidekazu Takahashi
- Oral Biomaterials Engineering, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| |
Collapse
|
34
|
Nagakura M, Tanimoto Y, Nishiyama N. Fabrication and physical properties of glass-fiber-reinforced thermoplastics for non-metal-clasp dentures. J Biomed Mater Res B Appl Biomater 2016; 105:2254-2260. [PMID: 27459321 DOI: 10.1002/jbm.b.33761] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2016] [Revised: 06/24/2016] [Accepted: 07/11/2016] [Indexed: 11/08/2022]
Abstract
Recently, non-metal-clasp dentures (NMCDs) made from thermoplastic resins such as polyamide, polyester, polycarbonate, and polypropylene have been used as removable partial dentures (RPDs). However, the use of such RPDs can seriously affect various tissues because of their low rigidity. In this study, we fabricated high-rigidity glass-fiber-reinforced thermoplastics (GFRTPs) for use in RPDs, and examined their physical properties such as apparent density, dynamic hardness, and flexural properties. GFRTPs made from E-glass fibers and polypropylene were fabricated using an injection-molding. The effects of the fiber content on the GFRTP properties were examined using glass-fiber contents of 0, 5, 10, 20, 30, 40, and 50 mass%. Commercially available denture base materials and NMCD materials were used as controls. The experimental densities of GFRTPs with various fiber contents agreed with the theoretical densities. Dynamic micro-indentation tests confirmed that the fiber content does not affect the GFRTP surface properties such as dynamic hardness and elastic modulus, because most of the reinforcing glass fibers are embedded in the polypropylene. The flexural strength increased from 55.8 to 217.6 MPa with increasing glass-fiber content from 0 to 50 mass%. The flexural modulus increased from 1.75 to 7.42 GPa with increasing glass-fiber content from 0 to 50 mass%, that is, the flexural strength and modulus of GFRTP with a fiber content of 50 mass% were 3.9 and 4.2 times, respectively, those of unreinforced polypropylene. These results suggest that fiber reinforcement has beneficial effects, and GFRTPs can be used in NMCDs because their physical properties are better than those of controls. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2254-2260, 2017.
Collapse
Affiliation(s)
- Manamu Nagakura
- Department of Dental Biomaterials, Nihon University School of Dentistry at Matsudo, 2-870-1 Sakaecho Nishi, Matsudo, Chiba, 271-8587, Japan
| | - Yasuhiro Tanimoto
- Department of Dental Biomaterials, Nihon University School of Dentistry at Matsudo, 2-870-1 Sakaecho Nishi, Matsudo, Chiba, 271-8587, Japan
| | - Norihiro Nishiyama
- Department of Dental Biomaterials, Nihon University School of Dentistry at Matsudo, 2-870-1 Sakaecho Nishi, Matsudo, Chiba, 271-8587, Japan
| |
Collapse
|
35
|
Hamanaka I, Shimizu H, Takahashi Y. Bond strength of a chairside autopolymerizing reline resin to injection-molded thermoplastic denture base resins. J Prosthodont Res 2016; 61:67-72. [PMID: 27238884 DOI: 10.1016/j.jpor.2016.04.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 04/22/2016] [Accepted: 04/30/2016] [Indexed: 10/21/2022]
Abstract
PURPOSE This study evaluated the shear bond strength of a chairside autopolymerizing reline resin to injection-molded thermoplastic denture base resins. METHODS Four kinds of injection-molded thermoplastic resins (two polyamides, a polyethylene terephthalate copolymer and a polycarbonate) and PMMA, as a control, were tested. The eight types of surface treatment: ((1) no treatment, (2) air abrasion, (3) dichloromethane, (4) ethyl acetate, (5) 4-META/MMA-TBB resin, (6) air abrasion and 4-META/MMA-TBB resin, (7) tribochemical silica coating, and (8) tribochemical silica coating and 4-META/MMA-TBB resin) were applied to each specimen. The chairside autopolymerizing reline resins were bonded to disks of the injection-molded thermoplastic denture base resins. All of the specimens were immersed in water for 4 months and then thermocycled for 10,000 cycles in water between 5 and 55°C. The shear bond strengths were determined. RESULTS The shear bond strengths of the two polyamides treated using air abrasion, dichloromethane and ethyl acetate and no treatment were exceedingly low. The greatest bond strength was recorded for the polyethylene terephthalate copolymer specimens treated with tribochemical silica coating and 4-META/MMA-TBB resin (22.5MPa). The bond strengths of the other injection-molded thermoplastic denture base resins increased using 4-META/MMA-TBB resin. CONCLUSIONS Tribochemical silica coating and 4-META/MMA-TBB resin were the most effective surface treatments among all denture base resins tested.
Collapse
Affiliation(s)
- Ippei Hamanaka
- Division of Removable Prosthodontics, Fukuoka Dental College, Fukuoka, Japan.
| | - Hiroshi Shimizu
- Division of Biomaterials, Kyushu Dental University, Fukuoka, Japan
| | - Yutaka Takahashi
- Division of Removable Prosthodontics, Fukuoka Dental College, Fukuoka, Japan
| |
Collapse
|
36
|
Agha H, Flinton R, Vaidyanathan T. Optimization of Fracture Resistance and Stiffness of Heat-Polymerized High Impact Acrylic Resin with Localized E-Glass FiBER FORCE® Reinforcement at Different Stress Points. J Prosthodont 2016; 25:647-655. [PMID: 26990705 DOI: 10.1111/jopr.12477] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/30/2016] [Indexed: 11/28/2022] Open
Abstract
PURPOSE Dentures are subject to fracture through flexural stresses during masticatory function. Distribution of stresses under flexural loading varies from compressive to tensile stress along the thickness of the denture cross section. The goal of this investigation was to evaluate the effect of reinforcing compressive, tensile, and no stress regions of flexurally loaded rectangular bars of heat-cured denture base acrylic resin reinforced with tough E-Glass FiBER FORCE (GFF) on their fracture resistance under flexural loading. MATERIALS AND METHODS Forty rectangular specimens (65 mm long × 10 mm wide × 2.5 mm thick) were prepared and divided into four groups (n = 10). Group FN had no fiber reinforcement, group FM had fiber in the middle at the no-stress neutral axis, group FC had fiber close to the surface on the compressive stress side, and group FT had the fiber close to the surface on the tensile stress side. The effect of GFF reinforcement on flexural strength (FS), flexural toughness (TG), and flexural modulus of elasticity (MOE) was evaluated. RESULTS The mean and (SD) of the FS, TG, and MOE varied as follows. FS (MPa): group FN: 91.49 (7.88); group FM: 102.83 (13.5); group FC: 107.68 (11.21); group FT: 141.46 (14.77). TG (mJ/mm3 ): group FN: 0.171 (0.026); group FM: 0.236 (0.033); group FC: 0.156 (0.032); group FT: 0.347 (0.010). MOE (MPa): group FN: 2682 (761); group FM: 2601 (417); group FC: 4188 (1012); group FT: 4215 (674). Statistical analysis showed that reinforcement on the tensile side of the neutral axis yielded improvement in all properties evaluated. CONCLUSIONS Placement of the GFF close to the tensile stress side surface of the bar increased the resistance to elastic deformation (i.e., higher MOE or stiffness) and the stress level needed for flexural fracture (i.e., higher FS). In addition, more energy was absorbed by reinforced specimens before fracture occurred (i.e., higher toughness). Localized reinforcement targeting tensile stress centers is thus a practical way to improve clinical durability of dentures against intra- and extraoral fracture.
Collapse
Affiliation(s)
- Haitham Agha
- Department of Restorative Clinical Science, University of Missouri-Kansas City, Kansas City, MO
| | - Robert Flinton
- Department of Restorative Dentistry, Rutgers School of Dental Medicine, Newark, NJ
| | - Tritala Vaidyanathan
- Department of Restorative Dentistry, Rutgers School of Dental Medicine, Newark, NJ
| |
Collapse
|
37
|
Fang J, Wang C, Li Y, Zhao Z, Mei L. Comparison of bacterial adhesion to dental materials of polyethylene terephthalate (PET) and polymethyl methacrylate (PMMA) using atomic force microscopy and scanning electron microscopy. SCANNING 2016; 38:665-670. [PMID: 26991988 DOI: 10.1002/sca.21314] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2015] [Accepted: 02/19/2016] [Indexed: 02/05/2023]
Affiliation(s)
- Jie Fang
- State Key Laboratory of Oral Diseases; West China Hospital of Stomatology; Sichuan University; Chengdu China
| | - Chuanyong Wang
- State Key Laboratory of Oral Diseases; West China Hospital of Stomatology; Sichuan University; Chengdu China
| | - Yifei Li
- Department of Pediatric Cardiovascular Disease; West China Second University Hospital; Sichuan University; Chengdu China
| | - Zhihe Zhao
- State Key Laboratory of Oral Diseases; West China Hospital of Stomatology; Sichuan University; Chengdu China
| | - Li Mei
- State Key Laboratory of Oral Diseases; West China Hospital of Stomatology; Sichuan University; Chengdu China
- Department of Oral Sciences; Faculty of Dentistry; University of Otago; Dunedin New Zealand
| |
Collapse
|
38
|
Hamanaka I, Iwamoto M, Lassila LVJ, Vallittu PK, Takahashi Y. Wear resistance of injection-molded thermoplastic denture base resins. ACTA BIOMATERIALIA ODONTOLOGICA SCANDINAVICA 2016. [PMID: 28642909 PMCID: PMC5433203 DOI: 10.3109/23337931.2015.1135747] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Objective This study investigated the wear resistance of injection-molded thermoplastic denture base resins using nanoindentation instrument. Materials and methods Six injection-molded thermoplastic denture base resins (two polyamides, two polyesters, one polycarbonate, one polymethylmethacrylate [PMMA]) and a PMMA conventional heat-polymerized denture-based polymer control were tested. Elastic modulus, hardness, wear depth, and roughness were calculated using a nanoindentation instrument. Results Elastic modulus and hardness of the injection-molded thermoplastic denture base resins were significantly lower than those of the PMMA conventional heat-polymerized denture-based polymer. Wear depth of polycarbonate and PMMA conventional heat-polymerized denture-based polymer were significantly higher than that of other injection-molded thermoplastic denture base resins. The roughness of injection-molded thermoplastic denture base resins was significantly more than that of PMMA conventional heat-polymerized denture-based polymer after testing. Conclusions Wear resistance of injection-molded thermoplastic denture base was low compared to PMMA conventional heat-polymerized denture-based polymers.
Collapse
Affiliation(s)
- Ippei Hamanaka
- Division of Removable Prosthodontics, Fukuoka Dental CollegeFukuokaJapan
| | - Misa Iwamoto
- Division of Removable Prosthodontics, Fukuoka Dental CollegeFukuokaJapan
| | - Lippo V J Lassila
- Department of Biomaterials Science, Turku Clinical Biomaterials Centre - TCBC, Institute of Dentistry, University of TurkuTurkuFinland
| | - Pekka K Vallittu
- Department of Biomaterials Science, Turku Clinical Biomaterials Centre - TCBC, Institute of Dentistry, University of TurkuTurkuFinland.,Division for Welfare, City of TurkuTurkuFinland
| | - Yutaka Takahashi
- Division of Removable Prosthodontics, Fukuoka Dental CollegeFukuokaJapan
| |
Collapse
|
39
|
Iwata Y. Assessment of clasp design and flexural properties of acrylic denture base materials for use in non-metal clasp dentures. J Prosthodont Res 2016; 60:114-22. [PMID: 26769352 DOI: 10.1016/j.jpor.2015.11.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Revised: 10/25/2015] [Accepted: 11/03/2015] [Indexed: 11/17/2022]
Abstract
PURPOSE The purpose of this study was to investigate the possibilities of utilizing new acrylic denture base materials in resin clasps using three-point flexural tests and cantilever beam tests. METHODS Seven non-metal clasp denture (NMCD) materials and four acrylic denture base materials were used for three-point flexural tests and six NMCD materials and three acrylic denture base materials were used for cantilever beam tests. The flexural strength, elastic modulus, and 0.05% proof stress were measured by three-point flexural tests according to International Organization for Standardization (ISO) 20795-1. And load at 0.5mm deformation, elastic modulus were measured by Cantilever beam tests. RESULTS For the three-point flexural tests, only materials that met the conditions for both flexural strength and elastic modulus were the polycarbonate Reigning N (REN) and the acrylics Acron (AC), Pro Impact (PI), Procast DSP (PC) and IvoBase High Impact (HI) which are required in ISO 20795-1, Type 3 denture base materials. And for cantilever beam tests there was no significant difference between PI and either EstheShot (ES), EstheShot Bright (ESB), REN or Acry Tone (ACT) in load at 0.5mm deformation, and no significant difference between PI and either Lucitone FRS (LTF), ES, ESB, REN or ACT in elastic modulus. CONCLUSIONS The results thus suggested that some of the acrylic materials used as denture base materials may also be usable for NMCDs, and that the flexural properties of the acrylic material PI resemble those of ES, ESB and ACT, meaning that similar clasp designs may also be feasible.
Collapse
Affiliation(s)
- Yoshihiro Iwata
- Department of Oral Function and Rehabilitation, Nihon University School of Dentistry at Matsudo, Japan; Nihon University Graduate School of Dentistry at Matsudo, Japan.
| |
Collapse
|
40
|
Sasaki H, Hamanaka I, Takahashi Y, Kawaguchi T. Effect of Reinforcement on the Flexural Properties of Injection-Molded Thermoplastic Denture Base Resins. J Prosthodont 2015; 26:302-308. [DOI: 10.1111/jopr.12419] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/16/2015] [Indexed: 11/30/2022] Open
Affiliation(s)
- Hirono Sasaki
- Division of Removable Prosthodontics; Fukuoka Dental College; Fukuoka Japan
| | - Ippei Hamanaka
- Division of Removable Prosthodontics; Fukuoka Dental College; Fukuoka Japan
| | - Yutaka Takahashi
- Division of Removable Prosthodontics; Fukuoka Dental College; Fukuoka Japan
| | - Tomohiro Kawaguchi
- Division of Removable Prosthodontics; Fukuoka Dental College; Fukuoka Japan
| |
Collapse
|
41
|
Abstract
All treatment involving the use of biomaterials in the body can affect the host in positive or negative ways. The microbiological environment in the oral cavity is affected by the composition and shape of the biomaterials used for oral restorations. This may impair the patients’ oral health and sometimes their general health as well. Many factors determine the composition of the microbiota and the formation of biofilm in relation to biomaterials such as, surface roughness, surface energy and chemical composition, This paper aims to give an overview of the scientific literature regarding the association between the chemical, mechanical and physical properties of dental biomaterials and oral biofilm formation, with emphasis on current research and future perspectives.
Collapse
Affiliation(s)
- Marit Øilo
- Department of Clinical Dentistry, Faculty of Medicine and Dentistry, University of Bergen, Aarstadveien 19, Bergen NO-5009, Norway
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +47-55586638; Fax: +47-55586489
| | - Vidar Bakken
- Department of Clinical Science, Faculty of Medicine and Dentistry, University of Bergen, Jonas Lies vei 65, The Laboratory Building, Bergen NO-5021, Norway; E-Mail:
| |
Collapse
|
42
|
Hamanaka I, Iwamoto M, Lassila LV, Vallittu PK, Shimizu H, Takahashi Y. The effect of cycling deflection on the injection-molded thermoplastic denture base resins. Acta Odontol Scand 2015; 74:67-72. [PMID: 25953322 DOI: 10.3109/00016357.2015.1042039] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
OBJECTIVE The aim of this study was to evaluate the effect of cycling deflection on the flexural behavior of injection-molded thermoplastic resins. MATERIALS AND METHODS Six injection-molded thermoplastic resins (two polyamides, two polyesters, one polycarbonate, one polymethyl methacrylate) and, as a control, a conventional heat-polymerized denture based polymer of polymethyl methacrylate (PMMA) were used in this study. The cyclic constant magnitude (1.0 mm) of 5000 cycles was applied using a universal testing machine to demonstrate plasticization of the polymer. Loading was carried out in water at 23ºC with eight specimens per group (n = 8). Cycling load (N) and deformation (mm) were measured. RESULTS Force required to deflect the specimens during the first loading cycle and final loading cycle was statistically significantly different (p < 0.05) with one polyamide based polymer (Valplast) and PMMA based polymers (Acrytone and Acron). The other polyamide based polymer (LucitoneFRS), polyester based polymers (EstheShot and EstheShotBright) and polycarbonate based polymer (ReigningN) did not show significant differences (p > 0.05). None of the materials fractured during the loading test. One polyamide based polymer (Valplast) displayed the highest deformation and PMMA based polymers (Acrytone and Acron) exhibited the second highest deformation among the denture base materials. CONCLUSION It can be concluded that there were considerable differences in the flexural behavior of denture base polymers. This may contribute to the fatigue resistance of the materials.
Collapse
Affiliation(s)
- Ippei Hamanaka
- a 1 Division of Removable Prosthodontics, Fukuoka Dental College , Fukuoka, Japan
- b 2 Department of Biomaterials Science and Turku Clinical Biomaterials Centre-TCBC, Institute of Dentistry, University of Turku , Turku, Finland
| | - Misa Iwamoto
- a 1 Division of Removable Prosthodontics, Fukuoka Dental College , Fukuoka, Japan
- b 2 Department of Biomaterials Science and Turku Clinical Biomaterials Centre-TCBC, Institute of Dentistry, University of Turku , Turku, Finland
| | - Lippo Vj Lassila
- b 2 Department of Biomaterials Science and Turku Clinical Biomaterials Centre-TCBC, Institute of Dentistry, University of Turku , Turku, Finland
| | - Pekka K Vallittu
- b 2 Department of Biomaterials Science and Turku Clinical Biomaterials Centre-TCBC, Institute of Dentistry, University of Turku , Turku, Finland
- c 3 City of Turku, Division for Welfare , Turku, Finland
| | - Hiroshi Shimizu
- d 4 Division of Biomaterials, Kyushu Dental University , Fukuoka, Japan
| | - Yutaka Takahashi
- a 1 Division of Removable Prosthodontics, Fukuoka Dental College , Fukuoka, Japan
| |
Collapse
|
43
|
Hamanaka I, Iwamoto M, Lassila L, Vallittu P, Shimizu H, Takahashi Y. Influence of water sorption on mechanical properties of injection-molded thermoplastic denture base resins. Acta Odontol Scand 2014; 72:859-65. [PMID: 24850507 DOI: 10.3109/00016357.2014.919662] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE This study investigated the influence of water sorption on certain mechanical properties of injection-molded thermoplastic denture base resins. MATERIALS AND METHODS Six thermoplastic resins (two polyamides, two polyesters, one polycarbonate, one polymethylmethacrylate) and a polymethylmethacrylate (PMMA) conventional heat-polymerized denture-based polymer, selected as a control, were tested. Specimens of each denture base material were fabricated according to ISO 1567 specifications and were either dry or water-immersed for 30 days (n = 10). The ultimate flexural strength, the flexural strength at the proportional limit and the elastic modulus of the denture base materials were calculated. RESULTS Water sorption significantly decreased the ultimate flexural strength, the flexural strength at the proportional limit and the elastic modulus of one of the polyamides and the PMMAs. It also significantly increased the ultimate flexural strength of the polycarbonate. CONCLUSION The mechanical properties of some injection-molded thermoplastic denture base resins changed after water sorption.
Collapse
Affiliation(s)
- Ippei Hamanaka
- Division of Removable Prosthodontics, Fukuoka Dental College , Fukuoka , Japan
| | | | | | | | | | | |
Collapse
|
44
|
Gharechahi J, Asadzadeh N, Shahabian F, Gharechahi M. Flexural strength of acrylic resin denture bases processed by two different methods. J Dent Res Dent Clin Dent Prospects 2014; 8:148-52. [PMID: 25346833 PMCID: PMC4206756 DOI: 10.5681/joddd.2014.027] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2013] [Accepted: 04/06/2014] [Indexed: 12/16/2022] Open
Abstract
Background and aims. The aim of this study was to compare flexural strength of specimens processed by conventional and injection-molding techniques.
Materials and methods. Conventional pressure-packed PMMA was used for conventional pressure-packed and injection-molded PMMA was used for injection-molding techniques. After processing, 15 specimens were stored in distilled water at room temperature until measured. Three-point flexural strength test was carried out. Statistical analysis was carried out by SPSS using t-test. Statistical significance was defined at P<0.05.
Results. Flexural strength of injection-polymerized acrylic resin specimens was higher than that of the conventional method (P=0.006). This difference was statistically significant (P=0.006).
Conclusion. Within the limitations of this study, flexural strength of acrylic resin specimens was influenced by the molding technique.
Collapse
Affiliation(s)
- Jafar Gharechahi
- Professor of Prosthodontics, Dental Research Center, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Nafiseh Asadzadeh
- Associate Professor of Prosthodontics, Dental Research Center, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Foad Shahabian
- Assistant Professor of Prosthodontics, Dental Research Center, School of Dentistry, Ahvaz University of Medical Sciences, Ahvaz, Iran
| | - Maryam Gharechahi
- Assistant Professor of Endodontics, Dental Research Center, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran
| |
Collapse
|
45
|
Osada H, Shimpo H, Hayakawa T, Ohkubo C. Influence of thickness and undercut of thermoplastic resin clasps on retentive force. Dent Mater J 2014; 32:381-9. [PMID: 23718997 DOI: 10.4012/dmj.2012-284] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Thermoplastic resin clasps have been used for esthetic denture rehabilitation. However, details of the design of the clasps have never been thoroughly clarified. This study investigated the retentive forces of thermoplastic resin clasps for non-metal clasp dentures. The retentive forces of all thermoplastic resin clasps depended on the elastic modulus of each resin, undercuts, thickness, and widths of the tested. A clasp with more than 0.5 mm undercut and 1.0 mm thickness is needed for Valplast. Similarly, more than 0.25 mm undercut and 1.0 mm thickness and 0.5 mm undercut and 0.5 mm thickness are required for Estheshot and Reigning, respectively; thus, the recommended clasp arm thickness is 1.0 mm to 1.5 mm for Valplast and Estheshot and 0.5 mm to 1.0 mm for Reigning when the width of the retentive arm is 5.0 mm.
Collapse
Affiliation(s)
- Hidekazu Osada
- Department of Removable Prosthodontics, Tsurumi University School of Dental Medicine, 2-1-3 Tsurumi, Tsurumi-ku, Yokohama, Kanagawa 230- 8501, Japan.
| | | | | | | |
Collapse
|
46
|
Fueki K, Ohkubo C, Yatabe M, Arakawa I, Arita M, Ino S, Kanamori T, Kawai Y, Kawara M, Komiyama O, Suzuki T, Nagata K, Hosoki M, Masumi SI, Yamauchi M, Aita H, Ono T, Kondo H, Tamaki K, Matsuka Y, Tsukasaki H, Fujisawa M, Baba K, Koyano K, Yatani H. Clinical application of removable partial dentures using thermoplastic resin. Part II: Material properties and clinical features of non-metal clasp dentures. J Prosthodont Res 2014; 58:71-84. [PMID: 24746524 DOI: 10.1016/j.jpor.2014.03.002] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Accepted: 03/18/2014] [Indexed: 11/28/2022]
Abstract
This position paper reviews physical and mechanical properties of thermoplastic resin used for non-metal clasp dentures, and describes feature of each thermoplastic resin in clinical application of non-metal clasp dentures and complications based on clinical experience of expert panels. Since products of thermoplastic resin have great variability in physical and mechanical properties, clinicians should utilize them with careful consideration of the specific properties of each product. In general, thermoplastic resin has lower color-stability and higher risk for fracture than polymethyl methacrylate. Additionally, the surface of thermoplastic resin becomes roughened more easily than polymethyl methacrylate. Studies related to material properties of thermoplastic resin, treatment efficacy and follow-up are insufficient to provide definitive conclusions at this time. Therefore, this position paper should be revised based on future studies and a clinical guideline should be provided.
Collapse
Affiliation(s)
- Kenji Fueki
- Japan Prosthodontic Society, Clinical Guideline Committee (2011-2012), Japan; Section of Removable Partial Prosthodontics, Tokyo Medical and Dental University, Japan.
| | - Chikahiro Ohkubo
- Japan Prosthodontic Society, Non-Metal Clasp Denture Expert Panel (2011-2012), Japan; Japan Prosthodontic Society, Removable Prosthodontics Expert Panel (2011-2012), Japan; Department of Removable Prosthodontics, Tsurumi University School of Dental Medicine, Japan
| | - Masaru Yatabe
- Japan Prosthodontic Society, Non-Metal Clasp Denture Expert Panel (2011-2012), Japan; Section of Removable Partial Prosthodontics, Tokyo Medical and Dental University, Japan; Tokyo Branch, Japan
| | - Ichiro Arakawa
- Japan Prosthodontic Society, Non-Metal Clasp Denture Expert Panel (2011-2012), Japan; Japan Prosthodontic Society, Removable Prosthodontics Expert Panel (2011-2012), Japan; Department of Partial and Complete Denture, School of Life Dentistry at Tokyo, The Nippon Dental University, Japan
| | - Masahiro Arita
- Japan Prosthodontic Society, Non-Metal Clasp Denture Expert Panel (2011-2012), Japan; Japan Prosthodontic Society, Removable Prosthodontics Expert Panel (2011-2012), Japan; Division of Occlusion & Maxillofacial Reconstruction, Department of Oral Function, School of Dentistry, Kyushu Dental University, Japan
| | - Satoshi Ino
- Japan Prosthodontic Society, Non-Metal Clasp Denture Expert Panel (2011-2012), Japan; Kanagawa Dental University Yokohama Clinic, Japan
| | - Toshikazu Kanamori
- Japan Prosthodontic Society, Non-Metal Clasp Denture Expert Panel (2011-2012), Japan; Tohoku & Hokkaido Branch, Japan
| | - Yasuhiko Kawai
- Japan Prosthodontic Society, Non-Metal Clasp Denture Expert Panel (2011-2012), Japan; Japan Prosthodontic Society, Removable Prosthodontics Expert Panel (2011-2012), Japan; Department of Removable Prosthodontics, Nihon University School of Dentistry at Matsudo, Japan
| | - Misao Kawara
- Japan Prosthodontic Society, Non-Metal Clasp Denture Expert Panel (2011-2012), Japan; Department of Oral Function and Rehabilitation, Nihon University School of Dentistry at Matsudo, Japan
| | - Osamu Komiyama
- Japan Prosthodontic Society, Non-Metal Clasp Denture Expert Panel (2011-2012), Japan; Department of Oral Function and Rehabilitation, Nihon University School of Dentistry at Matsudo, Japan
| | - Tetsuya Suzuki
- Japan Prosthodontic Society, Non-Metal Clasp Denture Expert Panel (2011-2012), Japan; Japan Prosthodontic Society, Removable Prosthodontics Expert Panel (2011-2012), Japan; Section of Oral Prosthetic Engineering, Tokyo Medical and Dental University, Japan
| | - Kazuhiro Nagata
- Japan Prosthodontic Society, Non-Metal Clasp Denture Expert Panel (2011-2012), Japan; Comprehensive Dental Care, The Nippon Dental University Niigata Hospital, Japan
| | - Maki Hosoki
- Japan Prosthodontic Society, Non-Metal Clasp Denture Expert Panel (2011-2012), Japan; Department of Fixed Prosthodontics, Institute of Health Biosciences, The University of Tokushima Graduate School, Japan
| | - Shin-ichi Masumi
- Japan Prosthodontic Society, Non-Metal Clasp Denture Expert Panel (2011-2012), Japan; Division of Occlusion & Maxillofacial Reconstruction, Department of Oral Function, School of Dentistry, Kyushu Dental University, Japan
| | - Mutsuo Yamauchi
- Japan Prosthodontic Society, Non-Metal Clasp Denture Expert Panel (2011-2012), Japan; Department of Prosthodontics, Division of Oral Functional Science and Rehabilitation, School of Dentistry, Asahi University, Japan
| | - Hideki Aita
- Japan Prosthodontic Society, Clinical Guideline Committee (2011-2012), Japan; Division of Occlusion and Removable Prosthodontics, Health Sciences University of Hokkaido, Japan
| | - Takahiro Ono
- Japan Prosthodontic Society, Clinical Guideline Committee (2011-2012), Japan; Department of Prosthodontics, Gerodontology and Oral Rehabilitation, Osaka University Graduate School of Dentistry, Japan
| | - Hisatomo Kondo
- Japan Prosthodontic Society, Clinical Guideline Committee (2011-2012), Japan; Department of Prosthodontics and Oral Implantology, Iwate Medical University, Japan
| | - Katsushi Tamaki
- Japan Prosthodontic Society, Clinical Guideline Committee (2011-2012), Japan; Department of Oral & Maxillofacial Rehabilitation, Removable Prosthetics, Kanagawa Dental College, Japan
| | - Yoshizo Matsuka
- Japan Prosthodontic Society, Clinical Guideline Committee (2011-2012), Japan; Department of Fixed Prosthodontics, Institute of Health Biosciences, The University of Tokushima Graduate School, Japan
| | - Hiroaki Tsukasaki
- Japan Prosthodontic Society, Clinical Guideline Committee (2011-2012), Japan; Department of Prosthodontics, Showa University, Japan
| | - Masanori Fujisawa
- Japan Prosthodontic Society, Clinical Guideline Committee (2011-2012), Japan; Division of Fixed Prosthodontics, School of Dentistry, Meikai University, Japan
| | - Kazuyoshi Baba
- Japan Prosthodontic Society, Clinical Guideline Committee (2011-2012), Japan; Department of Prosthodontics, Showa University, Japan
| | - Kiyoshi Koyano
- Japan Prosthodontic Society, Clinical Guideline Committee (2011-2012), Japan; Section of Implant and Rehabilitative Dentistry, Division of Oral Rehabilitation Faculty of Dental Science, Kyushu University, Japan
| | - Hirofumi Yatani
- Department of Fixed Prosthodontics, Osaka University Graduate School of Dentistry, Japan
| |
Collapse
|
47
|
Physical properties of polyamide-12 versus PMMA denture base material. BIOMED RESEARCH INTERNATIONAL 2014; 2014:150298. [PMID: 24734225 PMCID: PMC3966424 DOI: 10.1155/2014/150298] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Revised: 01/22/2014] [Accepted: 01/22/2014] [Indexed: 11/18/2022]
Abstract
OBJECTIVES Polyamide-12 (PA) is a flexible material suited for denture bases and clasping. This study investigated its potential aging effects with a focus on surface roughness, color stability, and elasticity. METHODS PA specimens (Valplast) of 40×10×2 mm and equally measuring PMMA specimens (Palapress) as control were fabricated. Color changes after storage in air, water, coffee, and red wine (n=10) were measured using the CIE L*a*b* color specification. Elasticity after thermocycling (1000, 3000, and 7000 cycles, n=15) was measured by three-point bending testing. Mean surface roughness (Ra) was determined after storage in the liquids mentioned above and thermocycling (n=10). RESULTS Tukey's HSD test (P<0.05) revealed statistically significant color changes of PA in red wine (ΔE=4.27 after 12 days, ΔE=6.90 after 12 days) and coffee (ΔE=3.93 after 36 days) but no color changes in PMMA. Elastic modulus of PA was 845 MPa and not affected by thermocycling (Tukey's HSD test, P>0.81). Dry specimens showed significantly decreased elasticity (P<0.001). Mean surface roughness (PA 0.20 μ m, PMMA 0.28 μ m) did not change significantly after thermocycling or storage (Mann-Whitney U-test, 0.16<P<0.65). SIGNIFICANCE PA exhibited a higher susceptibility to discoloration than PMMA. Neither surface roughness nor elasticity of PA was altered by artificial aging.
Collapse
|
48
|
Hamanaka I, Takahashi Y, Shimizu H. Properties of injection-molded thermoplastic polyester denture base resins. Acta Odontol Scand 2014; 72:139-44. [PMID: 24255964 DOI: 10.3109/00016357.2013.814803] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE This study investigated the properties of injection-molded thermoplastic polyester denture base resins. MATERIALS AND METHODS Two injection-molded thermoplastic polyester denture base resins (polyethylene terephthalate copolymer and polycycloalkylene terephthalate copolymer) were tested. Specimens of each denture base material were fabricated for flexural properties testing, Charpy impact testing and shear bond testing (n = 10). The flexural strength at the proportional limit, elastic modulus, Charpy impact strength and the shear bond strength of the two denture base materials were estimated. RESULTS The polycycloalkylene terephthalate copolymer denture base resin had significantly lower flexural strength at the proportional limit, lower elastic modulus, higher impact strength and lower shear bond strength compared to the polyethylene terephthalate copolymer denture base resin. CONCLUSION The properties of the injection-molded thermoplastic denture base resins composed of polyethylene terephthalate copolymer and polycycloalkylene terephthalate copolymer were different from each other. The polycycloalkylene terephthalate copolymer denture base resin had significantly lower flexural strength at the proportional limit, lower elastic modulus, higher impact strength and lower shear bond strength compared to the polyethylene terephthalate copolymer denture base resin.
Collapse
Affiliation(s)
- Ippei Hamanaka
- Division of Removable Prosthodontics, Fukuoka Dental College , Fukuoka , Japan
| | | | | |
Collapse
|
49
|
Kawara M, Iwata Y, Iwasaki M, Komoda Y, Iida T, Asano T, Komiyama O. Scratch test of thermoplastic denture base resins for non-metal clasp dentures. J Prosthodont Res 2013; 58:35-40. [PMID: 24332086 DOI: 10.1016/j.jpor.2013.10.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Revised: 10/10/2013] [Accepted: 10/15/2013] [Indexed: 12/01/2022]
Abstract
PURPOSE Several thermoplastic denture base resins have been introduced for the fabrication of non-metal clasp dentures. Although the surface of these materials is easily damaged, the surface roughness and characteristics of scratches created have not been evaluated. The purpose of this study was to evaluate the surface roughness of thermoplastic resins using a scratch test for the development of future materials. METHODS Four thermoplastic (polyamide: Valplast(®); VLP and Lucitone FRS(®); FRS, polyethylene terephthalate: EstheShot(®); ES, and polyester: EstheShot Bright(®); ESB) and two conventional acrylic (Heat-polymerizing: Urban(®); HC, and Pour type auto-polymerizing: Pro-Cast DSP(®); PR) denture base resins were examined. Eight specimens, approximately 10mm×10mm×30mm in size, of each material were fabricated. Scratch test was performed by a scratch tester with a diamond indenter of 10-μm radius and cone angle 90°, applying a constant load of 500mN, and 2-mm-long scratches were made. The scratch marks were studied under 3D laser measuring microscope and cross-section profiles at approximately 0.5mm, 1.0mm, and 1.5mm from the starting point were extracted and measured with analysis software. Data from 24 cross-section profiles in each denture base material were analyzed. RESULTS The maximum depths of ES, ESB and FRS were greater than VLP, PR and HC, and the scratch widths of ES, ESB, FRS and VPL were greater than PR and HC. CONCLUSIONS The results showed that the surface of thermoplastic denture base resins was easily damaged compared to polymethyl methacrylate.
Collapse
Affiliation(s)
- Misao Kawara
- Department of Oral Function and Rehabilitation, Nihon University School of Dentistry at Matsudo, Japan.
| | - Yoshihiro Iwata
- Nihon University Graduate School of Dentistry at Matsudo, Japan
| | | | | | - Takashi Iida
- Department of Oral Function and Rehabilitation, Nihon University School of Dentistry at Matsudo, Japan
| | - Takashi Asano
- Department of Oral Function and Rehabilitation, Nihon University School of Dentistry at Matsudo, Japan
| | - Osamu Komiyama
- Department of Oral Function and Rehabilitation, Nihon University School of Dentistry at Matsudo, Japan
| |
Collapse
|
50
|
Hamanaka I, Shimizu H, Takahashi Y. Shear bond strength of an autopolymerizing repair resin to injection-molded thermoplastic denture base resins. Acta Odontol Scand 2013; 71:1250-4. [PMID: 23339746 DOI: 10.3109/00016357.2012.757645] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE This study investigated the shear bond strength of an autopolymerizing repair resin to injection-molded thermoplastic denture base resins. MATERIALS AND METHODS Four injection-molded thermoplastic resins (two polyamides, a polyethylene terephthalate copolymer and a polycarbonate) were used in this study. The specimens were divided into eight groups according to the type of surface treatment given: (1) no treatment, (2) air abrasion with alumina, (3) dichloromethane, (4) ethyl acetate, (5) 4-META/MMA-TBB resin, (6) alumina and 4-META/MMA-TBB resin, (7) tribochemical silica coating or (8) tribochemical silica coating and 4-META/MMA-TBB resin. Half of the specimens in groups 1, 5, 6 and 8 were thermocycled for 10,000 cycles in water between 5-55°C with a dwell time of 1 min at each temperature. The shear bond strengths were determined. RESULTS The shear bond strengths to the two polyamides treated with alumina, dichloromethane and ethyl acetate and no treatment were very low. The greatest post-thermocycling bond strengths to polyamides were recorded for the specimens treated with tribochemical silica coating and 4-META/MMA-TBB resin (PA12: 16.4 MPa, PACM12: 17.5 MPa). The greatest post-thermocycling bond strengths to polyethylene terephthalate copolymer and polycarbonate were recorded for the treatment with alumina and 4-META/MMA-TBB resin (22.7 MPa, 20.8 MPa). CONCLUSION Polyamide was exceedingly difficult to bond to an autopolymerizing repair resin; the shear bond strength improved using tribochemical silica coating followed by the application of 4-META/MMA-TBB resin. Both polyethylene terephthalate copolymer and polycarbonate were originally easy to bond to an autopolymerizing repair resin. However, with 4-META/MMA-TBB resin, the bond was more secure.
Collapse
Affiliation(s)
- Ippei Hamanaka
- Division of Removable Prosthodontics, Fukuoka Dental College, Fukuoka, Japan.
| | | | | |
Collapse
|