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Bassiouny D, Petersmann S, Zohdy M, Morsi T, Taha D. Trueness and intaglio fit of custom-made polyetheretherketone post-and-cores fabricated using different techniques. J Prosthet Dent 2024:S0022-3913(24)00457-8. [PMID: 39089926 DOI: 10.1016/j.prosdent.2024.06.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2024] [Revised: 06/28/2024] [Accepted: 06/28/2024] [Indexed: 08/04/2024]
Abstract
STATEMENT OF PROBLEM Applications of polyetheretherketone (PEEK) as a promising alternative to ceramic materials have extended to include post-and-cores. However, information regarding the available fabrication techniques for producing custom-made PEEK post-and-cores and their effect on accuracy is still scarce. PURPOSE The purpose of this in vitro study was to evaluate the trueness and intaglio fit of custom-made PEEK post-and-cores fabricated using different techniques. MATERIAL AND METHODS Ten mandibular second premolars were collected, decoronated, and endodontically treated. For the fabrication of custom-made post-and-cores, each post space was prepared, scanned, and designed by using the exocad software program. Each reference design was used to fabricate PEEK post-and-cores with 3 different techniques (N=30): group P, heat pressing; group S, subtractive manufacturing, and group A, additive manufacturing. All the fabricated restorations were scanned, providing the test data as standard tessellation language (STL) files, which were imported with the reference data into a reverse engineering software program to evaluate the 3D trueness of each fabrication technique. To evaluate the intaglio fit, restorations coated with silicone material were scanned to provide the test data as STL files, which were superimposed on the STL files of the scanned restorations. One-way analysis of variance (ANOVA) and 2-way mixed model ANOVA tests were used to analyze the data (α=.05). RESULTS For 3D trueness, root mean square (RMS) values representing the deviations between the scans of the fabricated restorations and the reference designs varied significantly among different groups (P<.001), with the highest mean deviation found in group A (102.8 ±31 µm), while the lowest mean deviation was found in group S (42.2 ±11 µm). For the intaglio fit, the deviations between the scans of the fabricated restorations and the scans of the coated restorations varied significantly among different groups (P<.001), with the highest mean deviation found in group A (228.4 ±47 µm), while the lowest mean deviation was found in group S (96.2 ±14 µm). Simple effects comparisons showed the highest value of deviation in the apical area in group A (P<.001). CONCLUSIONS Custom-made PEEK post-and-cores fabricated by using subtractive manufacturing and heat pressing techniques showed better trueness and intaglio fit compared with additively manufactured restorations. Before printed PEEK restorations can be considered a suitable alternative to pressed or milled ones, improvements are required to confirm their reliability.
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Affiliation(s)
- Dina Bassiouny
- Assistant Lecturer, Department of Fixed Prosthodontics, Faculty of Dentistry, Ain Shams University, Cairo, Egypt
| | - Sandra Petersmann
- Senior Researcher, DMiRE Research Center, Carinthia University of Applied Sciences, Villach, Austria
| | - Maged Zohdy
- Professor, Department of Fixed Prosthodontics, Faculty of Dentistry, Ain Shams University, Cairo, Egypt
| | - Tarek Morsi
- Professor, Department of Fixed Prosthodontics, Faculty of Dentistry, Ain Shams University, Cairo, Egypt; and Vice Dean of Postgraduate Affairs, Faculty of Oral and Dental Medicine, Misr International University, Cairo, Egypt
| | - Doaa Taha
- Associate Professor, Department of Fixed Prosthodontics, Faculty of Dentistry, Ain Shams University, Cairo, Egypt; Associate Professor, Department of Fixed Prosthodontics, School of Dentistry, Newgiza University, Giza, Egypt; and Visiting Researcher, Section Medical Materials Science & Technology, University Hospital Tübingen, Tübingen, Germany.
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Balhaddad AA, Garcia IM, Mokeem L, Alsahafi R, Majeed-Saidan A, Albagami HH, Khan AS, Ahmad S, Collares FM, Della Bona A, Melo MAS. Three-dimensional (3D) printing in dental practice: Applications, areas of interest, and level of evidence. Clin Oral Investig 2023:10.1007/s00784-023-04983-7. [PMID: 37017759 DOI: 10.1007/s00784-023-04983-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 03/28/2023] [Indexed: 04/06/2023]
Abstract
OBJECTIVES The aim of this review to overview three-dimensional (3D) printing technologies available for different dental disciplines, considering the applicability of such technologies and materials development. MATERIALS AND METHODS Source Arksey and O'Malley's five stages framework using PubMed, EMBASE, and Scopus (Elsevier) databases managed this review. Papers focusing on 3D printing in dentistry and written in English were screened. Scientific productivity by the number of publications, areas of interest, and the focus of the investigations in each dental discipline were extracted. RESULTS Nine hundred thirty-four studies using 3D printing in dentistry were assessed. Limited clinical trials were observed, especially in Restorative, endodontics, and pediatric dentistry. Laboratory or animal studies are not reliable for clinical success, suggesting that clinical trials are a good approach to validate the new methods' outcomes and ensure that the benefits outweigh the risk. The most common application for 3D printing technologies is to facilitate conventional dental procedures. CONCLUSIONS The constantly improving quality of 3D printing applications has contributed to increasing the popularity of these technologies in dentistry; however, long-term clinical studies are necessary to assist in defining standards and endorsing the safe application of 3D printing in dental practice. CLINICAL RELEVANCE The recent progress in 3D materials has improved dental practice capabilities over the last decade. Understanding the current status of 3D printing in dentistry is essential to facilitate translating its applications from laboratory to the clinical setting.
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Affiliation(s)
- Abdulrahman A Balhaddad
- Department of Restorative Dental Sciences, College of Dentistry, Imam Abdulrahman Bin Faisal University, P.O.Box 1982, Dammam, 31441, Saudi Arabia.
| | - Isadora Martini Garcia
- Clinical Assistant Professor, Division of Operative Dentistry, Department of General Dentistry, University of Maryland School of Dentistry, Baltimore, MD, 21201, USA
| | - Lamia Mokeem
- Ph.D. Program in Dental Biomedical Sciences, University of Maryland School of Dentistry, Baltimore, Maryland, USA
| | - Rashed Alsahafi
- Department of Restorative Dental Sciences, College of Dentistry, Umm Al-Qura University, Makkah, 24381, Saudi Arabia
| | - Ahmad Majeed-Saidan
- Division of Prosthodontics, Department of Advanced Oral Sciences and Therapeutics, University of Maryland School of Dentistry, Baltimore, MD, 21201, USA
| | - Hathal H Albagami
- Department of Restorative Dental Sciences, College of Dentistry, Taibah University, Medina, 42353, Saudi Arabia
| | - Abdul Samad Khan
- Department of Restorative Dental Sciences, College of Dentistry, Imam Abdulrahman Bin Faisal University, P.O.Box 1982, Dammam, 31441, Saudi Arabia
| | - Shakil Ahmad
- Directorate of Library Affairs, Imam Abdulrahman Bin Faisal University, P.O. Box 1982, Dammam, 31441, Kingdom of Saudi Arabia
| | - Fabricio Mezzomo Collares
- Department of Dental Materials, School of Dentistry, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Alvaro Della Bona
- Postgraduate Program in Dentistry, Dental School, University of Passo Fundo, Passo Fundo, Brazil
| | - Mary Anne S Melo
- Ph.D. Program in Dental Biomedical Sciences, University of Maryland School of Dentistry, Baltimore, Maryland, USA.
- Division of Operative Dentistry, Department of General Dentistry, University of Maryland School of Dentistry, Baltimore, Maryland, USA.
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Donmez MB, Yilmaz B, Yoon HI, Kahveci Ç, Schimmel M, Çakmak G. Effect of computer-aided design and computer-aided manufacturing technique on the accuracy of fixed partial denture patterns used for casting or pressing. J Dent 2023; 130:104434. [PMID: 36693586 DOI: 10.1016/j.jdent.2023.104434] [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: 06/11/2022] [Revised: 01/16/2023] [Accepted: 01/20/2023] [Indexed: 01/22/2023] Open
Abstract
OBJECTIVES To evaluate the effect of additive and subtractive manufacturing on the accuracy (trueness and precision) of fixed partial denture patterns (FPDPs) used for casting or pressing. MATERIALS AND METHODS A 3-unit complete coverage FPD on mandibular right first premolar and first molar teeth was virtually designed. Using the design data, FPD patterns were fabricated from an additively manufactured resin (PR, ProArt Print Wax) and 2 CAD-CAM wax discs (YW, ProArt CAD Wax Yellow and BW, ProArt CAD Wax Blue) (n = 10). Each pattern was then digitized with a scanner (CEREC Primescan) and evaluated for 3D surface deviation at 4 different surfaces (overall, external, marginal, and intaglio surfaces) by using a 3D analysis software (Medit Link). Root mean square (RMS) values were automatically calculated. Data were analyzed by using Kruskal-Wallis and Dunn's post hoc tests for trueness and precision (α= 0.05). RESULTS Significant differences were found among the RMS values for overall (P<.001) and each surface (P≤.040) evaluated. PR had the highest overall (P≤.011) and intaglio surface (P≤.01) deviations, while the difference between YW and BW was not significant (P≥.199). PR had the highest (P≤.027) and BW had the lowest (P≤.042) external surface mean RMS values. BW had higher mean marginal RMS value than YW (P=.047). For precision, significant differences were observed among test groups only for marginal RMS values (P=.002). PR had lower precision than BW (P=.002). CONCLUSIONS BW and YW FPDPs mostly had higher trueness compared with PR FPDPs. However, considering relatively smaller deviations at marginal and intaglio surfaces and the fact that patterns mostly had similar precision, clinical fit of FPDs fabricated by using tested patterns may be similar. CLINICAL SIGNIFICANCE Definitive 3-unit fixed partial dentures fabricated by using tested patterns may be similar. However, FPDs fabricated with tested additively manufactured resin patterns might result in more chairside adjustments than those fabricated with tested subtractively manufactured wax patterns.
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Affiliation(s)
- Mustafa Borga Donmez
- Department of Prosthodontics, Faculty of Dentistry, Istinye University, Istanbul, Turkey; Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, Bern, Switzerland.
| | - Burak Yilmaz
- Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, Bern, Switzerland; Department of Restorative, Preventive and Pediatric Dentistry, School of Dental Medicine, University of Bern, Bern, Switzerland; Division of Restorative and Prosthetic Dentistry, The Ohio State University College of Dentistry, Ohio, USA
| | - Hyung-In Yoon
- Department of Prosthodontics, School of Dentistry and Dental Research Institute, Seoul National University, Seoul, South Korea
| | - Çiğdem Kahveci
- Department of Prosthodontics, Faculty of Dentistry, Giresun University, Giresun, Turkey
| | - Martin Schimmel
- Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, Bern, Switzerland; Division of Gerodontology and Removable Prosthodontics, University Clinics of Dental Medicine, University of Geneva, Geneva, Switzerland
| | - Gülce Çakmak
- Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, Bern, Switzerland
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Campos MRD, Oliveira TTD, Botelho AL, Reis ACD. Mechanical, Chemical, and Biological Properties of 3D-Printed Abutments: A Systematic Review. JOURNAL OF ADVANCED ORAL RESEARCH 2022. [DOI: 10.1177/23202068221099772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Aim: A systematic review of the methods of 3D printing and the materials used so far for the manufacture of abutments was performed to evaluate whether their clinical use is indicated through the mechanical, chemical, and biological analyses carried out. Materials and Methods: An electronic search conducted by three independent reviewers was carried out in the PubMed, Web of Science, Cochrane Library, Science Direct, and Lilac databases. The inclusion criterion was researching articles in English that contained as subject the manufacturing of abutments through 3D printing/additive manufacturing. Any meta-analyses, reviews, book chapters, abstracts, letters, conferences papers, and studies without abutments printed were excluded. Results: We found 780 references, which after applying the exclusion criteria resulted in the final inclusion of seven articles for review. The studies had a high heterogeneity, showing different materials and methodologies to manufacture abutments, which makes a comparison between them difficult, and for this reason it was not possible to carry out a meta-analysis with the data found. Conclusions: Even with the limitations found in the present research, it is possible to conclude that printed abutments have adequate mechanical, chemical, and biological properties that can indicate their clinical use. 3D printing presents high accuracy and speed and can produce customized abutments according to each case.
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Affiliation(s)
- Murilo Rodrigues de Campos
- Department of Dental Materials and Prosthodontics, Ribeirão Preto Dental School, Ribeirão Preto, SP, Brazil
| | | | - André Luís Botelho
- Department of Dental Materials and Prosthodontics, Ribeirão Preto Dental School, Ribeirão Preto, SP, Brazil
| | - Andréa Cândido dos Reis
- Department of Dental Materials and Prosthodontics, Ribeirão Preto Dental School, Ribeirão Preto, SP, Brazil
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Additive or subtractive manufacturing of crown patterns used for pressing or casting: A trueness analysis. J Dent 2022; 124:104221. [PMID: 35820503 DOI: 10.1016/j.jdent.2022.104221] [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: 02/11/2022] [Revised: 07/05/2022] [Accepted: 07/08/2022] [Indexed: 11/20/2022] Open
Abstract
OBJECTIVES To investigate the effect of subtractive and additive manufacturing techniques on the trueness of crown patterns used for pressing or casting. MATERIAL AND METHODS A complete-coverage mandibular right first molar crown was designed in standard tessellation language (STL) format. This STL served as the control (C-STL) and was used to fabricate 30 crown patterns in 3D-printed resin (PR, ProArt Print Wax), millable wax suitable for casting (BW, ProArt CAD Wax Blue), and millable wax suitable for pressing (YW, ProArt CAD Wax Yellow) (n = 10). Subtractively manufactured patterns were fabricated by using a 5-axis milling unit (PrograMill PM7), while 3D-printed patterns were fabricated by using a digital light processing-based 3D printer (PrograPrint PR5; Ivoclar Vivadent, Schaan, Liechtenstein). All fabricated patterns were digitized by using an intraoral scanner (CEREC Primescan SW 5.2) to generate test-STLs. C-STL and test-STLs were transferred into a 3D analysis software (Medit Link v 2.4.4). Trueness evaluation was performed at 4 different surfaces (external, intaglio with margin, marginal, and intaglio without margin) and for complete scan meshes (overall) by using the root mean square (RMS) method. Data were analyzed with Kruskal-Wallis and Mann-Whitney U tests (α = .05). RESULTS RMS values varied significantly at all surfaces (P < .001), except for marginal surface (P = .151). PR had the highest RMS values at external surface (P ≤ .007), intaglio surfaces (with (P ≤ .003) and without margin (P ≤ .005)), and overall (P ≤ .01). No significant differences were observed between YW and BW (P ≥ .223). CONCLUSION Patterns fabricated by using subtractive manufacturing exhibited high trueness. The deviation values, in general, were small, particularly at intaglio and marginal surfaces; thus, clinical difference in crown-fit may be negligible using additive or subtractive technique. CLINICAL SIGNIFICANCE The fit of definitive crowns may be similar when tested crown patterns are additively or subtractively manufactured. However, crowns fabricated by using tested 3D-printed resin patterns may require more chairside adjustments compared with those fabricated by using subtractively manufactured wax patterns.
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Taha D, Cesar PF, Sabet A. Influence of different combinations of CAD-CAM crown and customized abutment materials on the force absorption capacity in implant supported restorations - In vitro study. Dent Mater 2021; 38:e10-e18. [PMID: 34952710 DOI: 10.1016/j.dental.2021.12.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 12/09/2021] [Accepted: 12/15/2021] [Indexed: 11/03/2022]
Abstract
OBJECTIVES To evaluate the force absorption capacity of implant supported restorations utilizing different CAD-CAM materials for the fabrication of crowns and customized abutments. METHODS 80 titanium inserts were scanned to design customized abutments and crowns. The specimens were divided into four groups (n = 20/material): (Z): zirconia, (P): PEEK, (V): VITA Enamic, and (E): IPS e.max. Each group was subdivided into two subgroups according to customized abutment material: (Z) zirconia, and (P) for PEEK. For the assessment of force absorption, all specimens were loaded in a universal testing machine, applied loads curves were collected from the machine's software, and resulting loads curves were collected from forcemeter below the assembly. The slopes of all curves were analyzed using Two-way multivariate analysis of variance with pairwise comparisons using Tukey Post Hoc test (p < 0.05). RESULTS The curve progression of the applied and resulting forces varied among the investigated materials for each specimen. For zirconia abutments, ZZ showed the highest slope values of the applied and resulting force curves, followed by EZ, VZ, and PZ demonstrating statistically significant differences (P < .001). As for PEEK abutments, ZP and EP showed the least slope values, followed by PP then VP demonstrating statistically significant differences (P < .001). For Zirconia and e.max crowns, using PEEK abutments significantly increased slope loss. As for PEEK and Vita Enamic crowns changing abutment material did not significantly affect slope loss. SIGNIFICANCE Combining rigid crown materials with less rigid abutments might enhance their force absorption capacity. However, with less rigid crown materials a stiff substructure might be mandatory to preserve their force absorption behavior.
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Affiliation(s)
- Doaa Taha
- Department of Fixed Prosthodontics, Faculty of Dentistry, Ain Shams University, Cairo, Egypt; Section Medical Materials Science & Technology, University Hospital Tübingen, Tübingen, Germany.
| | - Paulo Francisco Cesar
- Department of Biomaterials and Oral Biochemistry, School of Dentistry, University of São Paulo, São Paulo, Brazil
| | - Ahmed Sabet
- Department of Fixed Prosthodontics, Faculty of Dentistry, Ain Shams University, Cairo, Egypt; Department of Fixed Prosthodontics, Faculty of Dentistry, British University, Cairo, Egypt
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Hata K, Ikeda H, Nagamatsu Y, Masaki C, Hosokawa R, Shimizu H. Development of Dental Poly(methyl methacrylate)-Based Resin for Stereolithography Additive Manufacturing. Polymers (Basel) 2021; 13:polym13244435. [PMID: 34960985 PMCID: PMC8706392 DOI: 10.3390/polym13244435] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 12/14/2021] [Accepted: 12/15/2021] [Indexed: 11/16/2022] Open
Abstract
Poly(methyl methacrylate) (PMMA) is widely used in dental applications. However, PMMA specialized for stereolithography (SLA) additive manufacturing (3D-printing) has not been developed yet. This study aims to develop a novel PMMA-based resin for SLA 3D-printing by mixing methyl methacrylate (MMA), ethylene glycol dimethacrylate (EGDMA), and PMMA powder in various mixing ratios. The printability and the viscosity of the PMMA-based resins were examined to determine their suitability for 3D-printing. The mechanical properties (flexural strength and Vickers hardness), shear bond strength, degree of conversion, physicochemical properties (water sorption and solubility), and cytotoxicity for L929 cells of the resulting resins were compared with those of three commercial resins: one self-cured resin and two 3D-print resins. EGDMA and PMMA were found to be essential components for SLA 3D-printing. The viscosity increased with PMMA content, while the mechanical properties improved as EGDMA content increased. The shear bond strength tended to decrease as EGDMA increased. Based on these characteristics, the optimal composition was determined to be 30% PMMA, 56% EGDMA, 14% MMA with flexural strength (84.6 ± 7.1 MPa), Vickers hardness (21.6 ± 1.9), and shear bond strength (10.5 ± 1.8 MPa) which were comparable to or higher than those of commercial resins. The resin’s degree of conversion (71.5 ± 0.7%), water sorption (19.7 ± 0.6 μg/mm3), solubility (below detection limit), and cell viability (80.7 ± 6.2% at day 10) were all acceptable for use in an oral environment. The printable PMMA-based resin is a potential candidate material for dental applications.
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Affiliation(s)
- Kentaro Hata
- Division of Oral Reconstruction and Rehabilitation, Department of Oral Functions, Kyushu Dental University, Fukuoka 803-8580, Japan; (K.H.); (C.M.); (R.H.)
- Division of Biomaterials, Department of Oral Functions, Kyushu Dental University, Fukuoka 803-8580, Japan; (Y.N.); (H.S.)
| | - Hiroshi Ikeda
- Division of Biomaterials, Department of Oral Functions, Kyushu Dental University, Fukuoka 803-8580, Japan; (Y.N.); (H.S.)
- Correspondence: ; Tel.: +81-93-582-1131; Fax: +81-93-592-1699
| | - Yuki Nagamatsu
- Division of Biomaterials, Department of Oral Functions, Kyushu Dental University, Fukuoka 803-8580, Japan; (Y.N.); (H.S.)
| | - Chihiro Masaki
- Division of Oral Reconstruction and Rehabilitation, Department of Oral Functions, Kyushu Dental University, Fukuoka 803-8580, Japan; (K.H.); (C.M.); (R.H.)
| | - Ryuji Hosokawa
- Division of Oral Reconstruction and Rehabilitation, Department of Oral Functions, Kyushu Dental University, Fukuoka 803-8580, Japan; (K.H.); (C.M.); (R.H.)
| | - Hiroshi Shimizu
- Division of Biomaterials, Department of Oral Functions, Kyushu Dental University, Fukuoka 803-8580, Japan; (Y.N.); (H.S.)
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Ren S, Jiang X, Lin Y, Di P. Crown Accuracy and Time Efficiency of Cement-Retained Implant-Supported Restorations in a Complete Digital Workflow: A Randomized Control Trial. J Prosthodont 2021; 31:405-411. [PMID: 34748653 DOI: 10.1111/jopr.13447] [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] [Received: 05/04/2021] [Revised: 10/20/2021] [Accepted: 10/24/2021] [Indexed: 12/21/2022] Open
Abstract
PURPOSE This is a clinical study to compare complete digital workflows generated using intraoral scanning and the split-file technique with a conventional workflow for cement-retained implant-supported restorations. MATERIALS AND METHODS Forty patients requiring posterior single-unit implant restorations were included. Twenty patients were randomly assigned to the complete digital workflow group, involving intraoral scanning and manufacture of cement-retained crowns using the split-file technique (test group). The remaining 20 patients were assigned to the hybrid workflow group (control group), involving conventional impressions and CAD-CAM fabricated crowns based on stone casts. Scanning of the crowns was performed before and after clinical adjustment using an intraoral scanner (TRIOS Color; 3Shape). Two 3D digital models were trimmed and superimposed to evaluate changes in dimensions using Geomagic Control 2014 software. Chair-side and laboratory times for the entire workflow were recorded. Independent-sample t tests were used for the statistical analysis. RESULTS All crowns were inserted without refabrication. The average maximum occlusal adjustment of the crowns, measured as maximum deviation of occlusal area in superimposed pre and post scans, was -212.7 ± 150.5 and -330.7 ± 192.5 µm in the test and control groups, respectively (p = 0.037). The average area of occlusal adjustment, measured as area of deviation larger than 100 µm, was 8.4 ± 8.1 and 17.1 ± 12.3 mm2 in the test and control groups, respectively (p = 0.012). The mesial and distal contact adjustment amounts, maximum deviations of proximal area, were -33.0 ± 96.2 and -48.6 ± 70.5 µm in the test group, and -3.7 ± 66.7 µm and -11.4 ± 106.7 µm in the control group, respectively. The mean chair-side time was 20.20 ± 3.00 and 26.65 ± 4.53 minutes in the test and control groups, respectively (p < 0.001). The mean laboratory time was 43.70 ± 5.56 and 84.55 ± 5.81 minutes in the test and control groups, respectively (p < 0.001). CONCLUSIONS Single-unit cement-retained crowns with complete digital workflows required fewer crown adjustments and had shorter clinical and laboratory times compared to conventional impressions and hybrid workflows. Digital impressions and the split-file technique provided customized abutments and cement-retained crowns, thus broadening the indications for digital workflows for implants.
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Affiliation(s)
- Shuxin Ren
- Department of Oral Implantology, Peking University School and Hospital of Stomatology, Beijing, China
| | - Xi Jiang
- Department of Oral Implantology, Peking University School and Hospital of Stomatology, Beijing, China
| | - Ye Lin
- Department of Oral Implantology, Peking University School and Hospital of Stomatology, Beijing, China
| | - Ping Di
- Department of Oral Implantology, Peking University School and Hospital of Stomatology, Beijing, China
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Comparison of Intaglio Surface Trueness of Interim Dental Crowns Fabricated with SLA 3D Printing, DLP 3D Printing, and Milling Technologies. Healthcare (Basel) 2021; 9:healthcare9080983. [PMID: 34442120 PMCID: PMC8391771 DOI: 10.3390/healthcare9080983] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 07/27/2021] [Accepted: 08/01/2021] [Indexed: 11/17/2022] Open
Abstract
This study aimed to evaluate the intaglio surface trueness of interim dental crowns fabricated with three 3-dimensional (3D) printing and milling technologies. Dental crown was designated and assigned as a computer-aided design (CAD) reference model (CRM). Interim dental crowns were fabricated based on CRM using two types of 3D printer technologies (stereolithography apparatus and digital light processing) and one type of milling machine (n = 15 per technology). The fabricated interim dental crowns were obtained via 3D modeling of the intaglio surface using a laboratory scanner and designated as CAD test models (CTMs). The alignment and 3D comparison of CRM and CTM were performed based on the intaglio surface using a 3D inspection software program (Geomagic Control X). Statistical analysis was validated using one-way analysis of variance and Tukey HSD test (α = 0.05). There were significant differences in intaglio surface trueness between the three different fabrication technologies, and high trueness values were observed in the milling group (p < 0.05). In the milling group, there was a significant difference in trueness according to the location of the intaglio surface (p < 0.001). In the manufacturing process of interim dental crowns, 3D printing technologies showed superior and uniform manufacturing accuracy than milling technology.
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Taha D, Sabet A. In vitro evaluation of material dependent force damping behavior of implant-supported restorations using different CAD-CAM materials and luting conditions. J Prosthet Dent 2021; 126:93.e1-93.e9. [PMID: 33933269 DOI: 10.1016/j.prosdent.2021.03.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 03/17/2021] [Accepted: 03/18/2021] [Indexed: 11/16/2022]
Abstract
STATEMENT OF PROBLEM Although force-damping behavior that matches natural teeth may be unobtainable, an optimal combination of crown material and luting agent might have a beneficial effect on the force absorption capacity of implant-supported restorations. However, the force-absorbing behavior of various restorative materials has not yet been satisfactorily investigated. PURPOSE The purpose of this in vitro study was to evaluate the material dependent force-damping behavior of implant-supported crowns fabricated from different computer-aided design and computer-aided manufacturing (CAD-CAM) materials luted to implant abutments under different conditions. MATERIAL AND METHODS Titanium inserts (N=84) were screwed to implant analogs, scanned to design zirconia abutments, and divided into 4 groups to receive CAD-CAM fabricated crowns in 4 materials: zirconia, polyetheretherketone (PEEK), polymer-infiltrated ceramics (VITA ENAMIC), and lithium disilicate (e.max). The crowns were subdivided as per the luting agent: none, interim cement, and adhesive resin cement. Measurements were performed by loading specimens in a universal testing machine with an increasing force and measuring the resulting force with a digital forcemeter, followed by image processing and data acquisition. Two-way multivariate analysis of variance (MANOVA) was used to assess all interactions with multiple pairwise comparisons (α=.05). RESULTS The curve progression of the applied and resulting forces varied significantly among the investigated materials, resulting in differently inclined slopes for each material (P<.001). With no cementation, the mean slope values of the resulting force curves ranged from 77.5 ±0.03 degrees for zirconia, followed by 71.8 ±0.03 degrees for lithium disilicate, 56.2 ±0.1 degrees for polymer-infiltrated ceramics, and 51.1 ±0.01 degrees for polyetheretherketone. With interim cementation, the mean slope values ranged from 75.4 ±0.01 degrees for zirconia, followed by 70.05 ±0.02 degrees for lithium disilicate, 56.1 ±0.02 degrees for polymer-infiltrated ceramics, and 52.2 ±0.1 degrees for polyetheretherketone. As with adhesive cementation, curve slopes ranged from 73.2 ±0.02 degrees for zirconia, followed by 70.5 ±0.2 degrees for lithium disilicate, 55.9 ±0.04 degrees for polymer-infiltrated ceramics, and 52.3 ±0.1 degrees for polyetheretherketone. Slope loss was significant after the cementation of zirconia and lithium disilicate crowns but less significant for polymer-infiltrated ceramics and polyetheretherketone. CONCLUSIONS Force damping is generally material dependent, yet implant-supported crowns fabricated from resilient materials such as polymer-infiltrated ceramics and PEEK show better force absorption than rigid materials such as zirconia and lithium disilicate ceramics. Furthermore, cementation of rigid materials significantly increased slope loss, indicating enhancement in their force-damping behavior, whereas less-rigid materials benefit less from cementation. Further studies are essential to investigate the effect of prosthetic materials on the stress distribution to the peri-implant bone in the crown-abutment-implant complex.
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Affiliation(s)
- Doaa Taha
- Visiting Researcher, Section Medical Materials Science & Technology, University Hospital Tübingen, Tübingen, Germany; Lecturer, Department of Fixed Prosthodontics, Faculty of Dentistry, Ain Shams University, Cairo, Egypt.
| | - Ahmed Sabet
- Associate Professor, Department of Fixed Prosthodontics, Faculty of Dentistry, Ain Shams University, Cairo, Egypt; Head of Fixed prosthodontics department, Faculty of Dentistry, British University, Cairo, Egypt
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