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Coelho SRG, da Silva MDD, Nunes TSBS, Viotto HEC, Marin DOM, Pero AC. Effect of immersion in disinfectants on the color stability of denture base resins and artificial teeth obtained by 3D printing. J Prosthodont 2024; 33:157-163. [PMID: 36740784 DOI: 10.1111/jopr.13663] [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: 07/13/2022] [Accepted: 01/27/2023] [Indexed: 02/07/2023] Open
Abstract
PURPOSE To evaluate the effect of immersion in disinfecting solutions on the color stability of denture base resins and artificial teeth obtained by 3D printing. MATERIALS AND METHODS Forty discs (15 × 3 mm) were obtained for each group: Lucitone 550 and Cosmos Denture 3D (denture base resins), Duralay and Cosmos TEMP 3D (artificial teeth resins). The discs were immersed in disinfectant solutions: Corega Tabs, 2% chlorhexidine digluconate, 0.25% sodium hypochlorite, and distilled water. Color measurements were obtained with a spectrophotometer before immersion in disinfectants and after the simulated periods of 6 and 12 months. Data (ΔE00 ) were submitted to mixed three-way ANOVA and Bonferroni post-test. RESULTS For denture base resins, Cosmos Denture 3D showed greater color change regardless of the solution and immersion time. The immersion time of 6 months influenced the color change of the denture base resins regardless of the disinfectant solution. For the artificial teeth resins, the immersion time of 12 months showed a significant color change when compared to 6 months. Cosmos TEMP 3D showed greater color change for all solutions, except for 0.25% sodium hypochlorite. Duralay resin showed greater color change in 2% chlorhexidine, regardless of immersion time. CONCLUSIONS For denture base resins, the immersion time significantly changed the color regardless of the solution. For artificial teeth resins, Cosmos TEMP 3D showed greater color changes in all solutions when compared to Duralay, except for 0.25% sodium hypochlorite. Chlorhexidine digluconate significantly changed the color of Duralay.
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Affiliation(s)
- Sabrina R G Coelho
- Department of Dental Materials and Prosthodontics, Araraquara Dental School, Universidade Estadual Paulista - UNESP, Araraquara, São Paulo, Brazil
| | - Marcela D D da Silva
- Department of Dental Materials and Prosthodontics, Araraquara Dental School, Universidade Estadual Paulista - UNESP, Araraquara, São Paulo, Brazil
| | - Thais S B S Nunes
- Department of Dental Materials and Prosthodontics, Araraquara Dental School, Universidade Estadual Paulista - UNESP, Araraquara, São Paulo, Brazil
| | - Hamile E C Viotto
- Department of Dental Materials and Prosthodontics, Araraquara Dental School, Universidade Estadual Paulista - UNESP, Araraquara, São Paulo, Brazil
| | - Danny O M Marin
- Department of Dentistry, Federal University of Santa Catarina - UFSC, Florianópolis, Santa Catarina, Brazil
| | - Ana C Pero
- Department of Dental Materials and Prosthodontics, Araraquara Dental School, Universidade Estadual Paulista - UNESP, Araraquara, São Paulo, Brazil
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Elrahim RAA, Shown A, Abdellah M, Abualsaud R, Helal MA. Impact of different chemical denture cleansers on the properties of digitally fabricated denture base resin materials. J Prosthodont 2023. [PMID: 37767991 DOI: 10.1111/jopr.13761] [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: 11/28/2022] [Revised: 08/25/2023] [Accepted: 08/28/2023] [Indexed: 09/29/2023] Open
Abstract
PURPOSE To compare the impact of three different chemical denture cleansers (CDCs) (Corega, chlorhexidine, and hydrogen peroxide) on the surface roughness, microhardness, and color stability of 3D-printed, computer-aided design and computer-aided manufacturing (CAD-CAM) milled, and heat-polymerized denture base material (DBM). MATERIALS AND METHODS A total of 420 disc-shaped specimens (10 ± 0.1 × 2 ±0.1 mm) were fabricated using three different construction techniques: three-dimensional (3D) printing (n = 140), CAD-CAM milling (n = 140), and heat-polymerization (n = 140). Sixty specimens (20 of each DBM) were used for baseline (pre-immersion) measurements (T1 ) for the tested surface properties (hardness [n = 10/material] and roughness [n = 10/material]). The remaining 360 specimens (n = 120/material) were investigated for surface roughness, microhardness, and color change after immersion for 1 year (T2 ) in distilled water or CDCs (n = 30/solution and n = 10/test). The data were analyzed using two-way ANOVA, one-way ANOVA followed by post-hoc Tukey's test at a significance level of less than 0.05. RESULTS Significant differences were observed in the effects of the tested CDCs on the surface roughness, micro-hardness, and color stability of varying DBM specimens (p < 0.05). Corega showed the highest surface roughness and color change in all DBMs while H2 O2 resulted in the lowest microhardness for all DBMs. The lowest changes in all tested properties were seen with distilled water followed by chlorhexidine. A significant effect of type of cleanser, denture base material, and the interaction between the two was seen on all measured properties (p < 0.05). CONCLUSIONS The tested CDCs significantly affected the surface properties of all DBMs but at varying degrees. Corega produced the highest negative effect on roughness and color change while H2 O2 dramatically affected the microhardness. Prolonged use of CDCs should be cautiously followed.
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Affiliation(s)
| | - Ahmed Shown
- Department of Prosthodontics, Faculty of Dental Medicine, Al-Azhar University, Cairo, Egypt
- Al Mouwasat Hospital, Al Madinah Al Mounawarah, KSA
| | - Mahmoud Abdellah
- Department of Dental Biomaterials, Faculty of Dental Medicine, Al-Azhar University, Assuit, Egypt
| | - Reem Abualsaud
- Department of Substitutive Dental Sciences, College of Dentistry, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Mohamed Ahmed Helal
- Department of Prosthodontics, Faculty of Dental Medicine, Al-Azhar University, Cairo, Egypt
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Nunes TSBS, Silva MDDD, Coelho SRG, Viotto HEDC, Pero AC. Effectiveness of disinfectant solutions associated or not with brushing on the biofilm control of a 3D printed-denture base resin. J Appl Oral Sci 2023; 31:e20230104. [PMID: 37466551 DOI: 10.1590/1678-7757-2023-0104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 06/12/2023] [Indexed: 07/20/2023] Open
Abstract
BACKGROUND The formation of biofilm on denture bases is a recurrent clinical problem that favors the development of denture stomatitis. The effectiveness of a hygiene protocol in a 3D-printed denture base resin is still uncertain. OBJECTIVE To evaluate of the effectiveness of immersion, associated or not with brushing in a soap solution, on the biofilm control of a 3D-printed denture base resin. METHODOLOGY Specimens of denture base resins [Cosmos Denture (COS) and Classico (CLA/control)] were contaminated in vitro with Candida albicans and immersed in sodium hypochlorite 0.25% (SH, alkaline peroxide) AP, chlorhexidine digluconate 2% (CD or PBS-Control), associated or not with brushing with 0.78% Lifebuoy soap. Roughness was evaluated before and after brushing and immersion. The effectiveness of the protocols was assessed by CFU/mL, cellular metabolism (XTT), scanning electron microscopy (SEM), and confocal scanning laser microscopy. Data were analyzed by T student, ANOVA/Welch, and Tukey/Gomes-Howell pos-hoc tests (α = 0.05). RESULTS CLA showed greater roughness than COS. CFU/mL and XTT were higher in COS resin with a higher hyphae formation. Immersion in SH and CD eliminated CFU/mL and reduced XTT for both resins, associated or not with brushing. AP reduced CFU/mL only when associated with brushing. CONCLUSIONS The biofilm on the 3D-printed resin was thicker and presumably more pathogenic, regardless of its smoother surface. Immersions in SH 0.25% and CD 2% are effective hygiene protocols for both resins, associated or not with brushing. AP should be recommended when associated with brushing with a Lifebuoy 0.78% solution.
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Affiliation(s)
- Thaís Soares Bezerra Santos Nunes
- Universidade Estadual Paulista (UNESP), Faculdade de Odontologia, Departamento de Materiais Dentários e Prótese, Araraquara, São Paulo, Brasil
| | - Marcela Dantas Dias da Silva
- Universidade Estadual Paulista (UNESP), Faculdade de Odontologia, Departamento de Materiais Dentários e Prótese, Araraquara, São Paulo, Brasil
| | - Sabrina Romão Gonçalves Coelho
- Universidade Estadual Paulista (UNESP), Faculdade de Odontologia, Departamento de Materiais Dentários e Prótese, Araraquara, São Paulo, Brasil
| | - Hamile Emanuella do Carmo Viotto
- Universidade Estadual Paulista (UNESP), Faculdade de Odontologia, Departamento de Materiais Dentários e Prótese, Araraquara, São Paulo, Brasil
| | - Ana Carolina Pero
- Universidade Estadual Paulista (UNESP), Faculdade de Odontologia, Departamento de Materiais Dentários e Prótese, Araraquara, São Paulo, Brasil
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Viana de Sousa T, Carolina Jordão C, Augusto Abreu-Pereira C, Gorayb Pereira AL, Barbugli PA, Klein MI, Pavarina AC. Hydrogen peroxide enhances the efficacy of photodynamic therapy against Candida albicans biofilms. BIOFOULING 2023; 39:94-109. [PMID: 36916295 DOI: 10.1080/08927014.2023.2189011] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 03/02/2023] [Accepted: 03/05/2023] [Indexed: 06/18/2023]
Abstract
The present study aimed to evaluate the effectiveness of hydrogen peroxide (H2O2) combined with antimicrobial photodynamic therapy (aPDT) on biofilms formed by Candida albicans strains which are either susceptible to or resistant to fluconazole. Biofilms were grown and treated with H2O2, followed by the application of Photodithazine® (P) and red light-emitting diode (LED) (L) either separately or combined (n = 12). After the treatment, biofilms were evaluated by estimating colony-forming unit ml-1, extracellular matrix components [water -soluble and -insoluble polysaccharides, proteins, extracellular DNA (eDNA)], biomass (total and insoluble dry-weight), and protein concentration. Biofilms formed by both strains presented a significant reduction in cell viability, biomass, extracellular matrix components (both types of polysaccharides, eDNA), and proteins (in the soluble and insoluble portion of biofilms) compared to the control. Microscopy images of the biofilms after treatments showed disarticulation of the matrix and scattered fungal cells. The application of H2O2 can disturb the organization of the extracellular matrix, and its association with aPDT potentiated the effect of the treatment.
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Affiliation(s)
- Tábata Viana de Sousa
- Department of Dental Materials and Prosthodontics, School of Dentistry at Araraquara, Univ Estadual Paulista - UNESP, Araraquara, SP, Brazil
| | - Cláudia Carolina Jordão
- Department of Dental Materials and Prosthodontics, School of Dentistry at Araraquara, Univ Estadual Paulista - UNESP, Araraquara, SP, Brazil
| | - César Augusto Abreu-Pereira
- Department of Dental Materials and Prosthodontics, School of Dentistry at Araraquara, Univ Estadual Paulista - UNESP, Araraquara, SP, Brazil
| | - Ana Luiza Gorayb Pereira
- Department of Dental Materials and Prosthodontics, School of Dentistry at Araraquara, Univ Estadual Paulista - UNESP, Araraquara, SP, Brazil
| | - Paula Aboud Barbugli
- Department of Dental Materials and Prosthodontics, School of Dentistry at Araraquara, Univ Estadual Paulista - UNESP, Araraquara, SP, Brazil
| | - Marlise Inêz Klein
- Department of Oral Diagnosis, Piracicaba Dental School, State University of Campinas (UNICAMP), Piracicaba, Brazil
| | - Ana Claudia Pavarina
- Department of Dental Materials and Prosthodontics, School of Dentistry at Araraquara, Univ Estadual Paulista - UNESP, Araraquara, SP, Brazil
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Disinfectant effects of Brazilian green propolis alcohol solutions on the Staphylococcus aureus biofilm of maxillofacial prosthesis polymers. J Prosthet Dent 2022; 128:1405-1411. [PMID: 33992467 DOI: 10.1016/j.prosdent.2021.03.025] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 03/06/2021] [Accepted: 03/08/2021] [Indexed: 01/02/2023]
Abstract
STATEMENT OF PROBLEM Brazilian green propolis may be an alternative product that reduces the development of a microbial biofilm on the polymers used for maxillofacial prostheses. However, its effects as a disinfectant have not been fully established. PURPOSE The purpose of this in vitro study was to investigate the effects of Brazilian green propolis alcohol solutions against the Staphylococcus aureus biofilm on polymers used in maxillofacial prostheses, the maxillofacial silicone elastomer (MDX4-4210), and specific acrylic resins for ocular prostheses. MATERIAL AND METHODS A total of 324 disk-shaped specimens (3×10 mm) of each material were fabricated. All specimens were contaminated with S. aureus (108 cells/mL) to assess the antibiofilm activity of immersion solutions and protocols. Thus, 162 specimens of each material were randomly distributed and equally divided into 5 groups of disinfectants and 1 control group: 3 separate groups of 2.5%, 5%, and 10% propolis alcohol solutions, 1 group of 5% propolis alcohol gel, a positive control group of 2% chlorhexidine gluconate, and a negative control group of distilled water. Specimens (n=9) were disinfected by immersion for 5, 10, and 15 minutes and immersed in culture medium for 24 hours. Any notable turgescence in the final medium was considered indicative of a biofilm. The effects of disinfectants were analyzed by a turbidity assay and by scanning electron microscopy. Data were analyzed descriptively. RESULTS The final medium with specimens disinfected with 10% propolis alcohol solution showed no turbidity, indicating constant efficacy against the S. aureus biofilm. Similarly, these findings were observed in the 2% chlorhexidine gluconate group. Scanning electron microscopy images demonstrated that the surface of the polymers treated with 10% propolis alcohol solution did not show bacterial colonies. CONCLUSIONS Disinfection with 10% green propolis alcohol solution was effective in eliminating the S. aureus biofilm from specimens of maxillofacial elastomer and N1 acrylic resin specific to ocular prostheses by immersion for 5 minutes.
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YILMAZ D, AKIN H. Antimicrobial Effect of Polyhexanide on Denture Base and Soft Lining Materials. CLINICAL AND EXPERIMENTAL HEALTH SCIENCES 2021. [DOI: 10.33808/clinexphealthsci.833576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Venkatachalam N, Ramesh N, Turuvekere P, Prasad SV, Ramees M, Kumar C. Evaluation of Efficacy of Four Disinfectants on Striated and Non-striated Orthodontic Instruments: An In Vitro Study. JOURNAL OF PHARMACY AND BIOALLIED SCIENCES 2020; 12:S254-S258. [PMID: 33149466 PMCID: PMC7595544 DOI: 10.4103/jpbs.jpbs_75_20] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 02/02/2020] [Accepted: 03/06/2020] [Indexed: 11/11/2022] Open
Abstract
Introduction: To achieve effective infection control only disinfecting instruments is not perfect when sterilization is an ideal method. Few chemical disinfection methods have disadvantage of not killing spores as cross infection is of great importance in dentistry; Standard sterilization and disinfection protocols must be followed by dental health care professionals for efficient infection control. Aim: The aim of this study was to evaluate the efficacy of undiluted concentrations of Durr Dental system, Bacillol, Savlon, and Dettol for disinfection of striated and nonstriated orthodontic instruments. Materials and Methods: Orthodontic instruments were divided into two groups. Each group of instrument was exposed to three microbes: Streptococcus mutans, Candida albicans, and Bacillus subtilis. Once the instruments were exposed to bacterium, they were immersed in four commercially available disinfectants: Durr Dental solution, Bacillol, Dettol, and Savlon. Culture streaks were taken at 5, 10, and 15 min of contact time and growth of organisms was observed on culture media. Results: All the four disinfectants showed no growth of bacteria and all were significantly effective. As per the immersion time factor, Durr system and Bacillol were more efficient than Dettol and Savlon. Conclusion: Study concluded that there was no growth of bacteria after disinfecting in all the four disinfectants. Dettol and Savlon were unable to eliminate B. subtilis at 5 min of contact time. All the disinfectants were effective in eliminating the microorganisms at 10 and 15 min postexposure.
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Affiliation(s)
| | - Niveddha Ramesh
- Department of Orthodontist, Avni Dental Care, Chennai, Tamil Nadu, India
| | - Prasanna Turuvekere
- Department of Orthodontics, Sri Siddhartha Academy of Higher Education, Tumakuru, Karnataka, India
| | - Sm Vignesh Prasad
- Department of Orthodontics, J.K.K. Nattaraja Dental College and Hospital, Kumarapalayam, Tamil Nadu, India
| | - Mohamad Ramees
- Department of Orthodontics, Sri Siddhartha Academy of Higher Education, Tumakuru, Karnataka, India
| | - Chethan Kumar
- Department of Orthodontics, Sri Siddhartha Academy of Higher Education, Tumakuru, Karnataka, India
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Panariello BHD, Klein MI, Mima EGDO, Pavarina AC. Fluconazole impacts the extracellular matrix of fluconazole-susceptible and -resistant Candida albicans and Candida glabrata biofilms. J Oral Microbiol 2018; 10:1476644. [PMID: 29887974 PMCID: PMC5990947 DOI: 10.1080/20002297.2018.1476644] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2018] [Accepted: 05/07/2018] [Indexed: 01/29/2023] Open
Abstract
Background: Fluconazole (FLZ) is a drug commonly used for the treatment of Candida infections. However, β-glucans in the extracellular matrices (ECMs) hinder FLZ penetration into Candida biofilms, while extracellular DNA (eDNA) contributes to the biofilm architecture and resistance. Methods: This study characterized biofilms of FLZ-sensitive (S) and -resistant (R) Candida albicans and Candida glabrata in the presence or absence of FLZ focusing on the ECM traits. Biofilms of C. albicans American Type Culture Collection (ATCC) 90028 (CaS), C. albicans ATCC 96901 (CaR), C. glabrata ATCC 2001 (CgS), and C. glabrata ATCC 200918 (CgR) were grown in RPMI medium with or without FLZ at 5× the minimum inhibitory concentration (37°C/48 h). Biofilms were assessed by colony-forming unit (CFU)/mL, biomass, and ECM components (alkali-soluble polysaccharides [ASP], water-soluble polysaccharides [WSP], eDNA, and proteins). Scanning electron microscopy (SEM) was also performed. Data were analyzed by parametric and nonparametric tests (α = 0.05). Results: In biofilms, FLZ reduced the CFU/mL of all strains (p < 0.001), except for CaS (p = 0.937). However, the ASP quantity in CaS was significantly reduced by FLZ (p = 0.034), while the drug had no effect on the ASP levels in other strains (p > 0.05). Total biomasses and WSP were significantly reduced by FLZ in the ECM of all yeasts (p < 0.001), but levels of eDNA and proteins were unaffected (p > 0.05). FLZ affected the cell morphology and biofilm structure by hindering hyphae formation in CaS and CaR biofilms, by decreasing the number of cells in CgS and CgR biofilms, and by yielding sparsely spaced cell agglomerates on the substrate. Conclusion: FLZ impacts biofilms of C. albicans and C. glabrata as evident by reduced biomass. This reduced biomass coincided with lowered cell numbers and quantity of WSPs. Hyphal production by C. albicans was also reduced.
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Affiliation(s)
- Beatriz Helena Dias Panariello
- Department of Cariology, Operative Dentistry and Dental Public Health, Indiana University- Purdue University Indianapolis, School of Dentistry, Indianapolis, IN, USA
| | - Marlise I Klein
- Department of Dental Materials and Prosthodontics, São Paulo State University (Unesp), School of Dentistry, Araraquara, São Paulo, Brazil
| | - Ewerton Garcia De Oliveira Mima
- Department of Dental Materials and Prosthodontics, São Paulo State University (Unesp), School of Dentistry, Araraquara, São Paulo, Brazil
| | - Ana Cláudia Pavarina
- Department of Dental Materials and Prosthodontics, São Paulo State University (Unesp), School of Dentistry, Araraquara, São Paulo, Brazil
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Antimicrobial and cytotoxic effects of denture base acrylic resin impregnated with cleaning agents after long-term immersion. Toxicol In Vitro 2018; 52:8-13. [PMID: 29807097 DOI: 10.1016/j.tiv.2018.05.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 05/23/2018] [Accepted: 05/24/2018] [Indexed: 11/20/2022]
Abstract
The coadjutant method for denture cleansing most used by denture wearers is immersion in chemical agents, which are toxic when in direct contact with cells. However, clinically, the contact between these chemical agents and prosthetic tissues does not occur directly, but rather with what remained impregnated into acrylic bases, even after rinsing the disinfected dentures. This study evaluated the antimicrobial and cytotoxic effects of a denture acrylic resin after successive cycles of daily overnight immersion in 1% sodium hypochlorite (1%NaClO) and 2% chlorhexidine digluconate (2%CHX), simulating the periods of 9 months or 1.5 year. Microbiological and cytotoxic assays were performed, respectively, by broth microdilution method (Candida albicans or Staphylococcus aureus) and MTT assay. Chemical residues of 2%CHX impregnated into the denture acrylic resin had an antimicrobial effect on both immersion periods, which was not observed with those of 1%NaClO. However, residues of 2%CHX were severely cytotoxic to human gingival fibroblasts compared to those of 1%NaClO and acrylic resin (not submitted to the denture cleansers), which were slightly cytotoxic. Even at low concentrations recommended for overnight soaking of removable dentures, the chemical residues of CHX may result in some degree of toxicity to the denture-bearing mucosa after long-term daily immersion.
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Masetti P, Arbeláez MIA, Pavarina AC, Sanitá PV, Jorge JH. Cytotoxic potential of denture base and reline acrylic resins after immersion in disinfectant solutions. J Prosthet Dent 2018; 120:155.e1-155.e7. [PMID: 29724556 DOI: 10.1016/j.prosdent.2018.01.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 01/09/2018] [Accepted: 01/09/2018] [Indexed: 10/17/2022]
Abstract
STATEMENT OF PROBLEM The daily immersion of dentures in disinfectant solutions can cause the incorporation of toxic substances in the acrylic resins, and studies evaluating the cumulative effect of disinfectant solutions on cell culture are lacking. PURPOSE The purpose of this in vitro study was to evaluate the cytotoxic potential of cell cultures of denture base and reline acrylic resins after immersion in disinfectant solutions. MATERIAL AND METHODS Disk-shaped specimens (14×1.2 mm) were obtained and divided into groups (n=9) according to the disinfectant solutions (distilled water [control], 2% chlorhexidine digluconate, 3.8% sodium perborate, 0.5% sodium hypochlorite, and apple vinegar) and to the storage period (0, 1, 3, and 6 months). Solutions were changed daily. After the different storage periods, specimens were immersed in culture medium for 24 hours, and extracts were obtained. Human keratinocytes were cultivated, and the cellular metabolism was evaluated by using Alamar Blue. Data were submitted to 3-way analysis of variance and Games-Howell post hoc tests (α=.05). RESULTS Both of the acrylic resins tested showed similar biocompatibility properties after immersion in different solutions (P=.400). Immersion in distilled water, 3.8% sodium perborate, and 0.5% sodium hypochlorite did not affect the cellular metabolism of the keratinocytes (P>.05), regardless of the immersion period and the type of acrylic resin (P>.05). Immersion in 2% chlorhexidine digluconate or apple vinegar resulted in high cytotoxicity over time, until the third month (P<.05), after which no changes were observed (P>.05). CONCLUSIONS The type of acrylic resin (base or reline) had no significant effect on the viability of cells. Vinegar and chlorhexidine digluconate solutions increased in cytotoxic effect over time, and were strongly cytotoxic after 6 months of immersion. Sodium perborate and sodium hypochlorite were noncytotoxic in all periods of time tested.
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Affiliation(s)
- Paula Masetti
- Postgraduate student, Araraquara Dental School, São Paulo State University (UNESP), Araraquara, Brazil
| | | | - Ana Claudia Pavarina
- Professor, Araraquara Dental School, São Paulo State University (UNESP), Araraquara, Brazil
| | - Paula Volpato Sanitá
- Professor, Araraquara Dental School, São Paulo State University (UNESP), Araraquara, Brazil
| | - Janaina Habib Jorge
- Professor, Araraquara Dental School, São Paulo State University (UNESP), Araraquara, Brazil
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Popescu MC, Bita BI, Tucureanu V, Vasilache D, Banu MA, Avram AM, Giurescu-Dumitrescu RA. Superficial and Inner Examination of a Microwave-Irradiated Dental Acrylic Resin and Its Metal-Polymer Interface. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2018; 24:49-59. [PMID: 29485028 DOI: 10.1017/s1431927618000089] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The aim of this study is to conduct an extended surface and cross-section characterization of a denture base acrylic resin subjected to 500, 650, and 750 W microwave irradiation for 2, 3, and 5 min to assess its morphological modifications. A commercial heat-cured powder was polymerized according to the manufacturer's specifications and distributed into 20 circular samples. A stainless-steel wire was partially embedded in half of the discs, in order to investigate the metal-polymer interface. High-resolution scanning electron microscopy (SEM) imaging, white light interferometry, roughness measurements and Fourier transform infrared spectrometry were employed for morphological and structural evaluation of the irradiated polymer. Superficial adaptation was discovered after 5 min exposure at 500 W, 650 W, and 750 W, revealing significant roughness correction for 750 W. SEM characterization revealed the inner alteration of the resin for the 750 W protocol and a metal-polymer gap developed regardless of the irradiation conditions. The considerable temperature fluctuations that the samples were subject to during the experiments did not essentially change the poly(methyl-methacrylate) bond structure.
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Affiliation(s)
- Marian C Popescu
- 1Nano-Scale Structuring and Characterization Laboratory,National Institute for Research and Development in Microtechnologies,126A Erou Iancu Nicolae Street,077190 Bucharest,Romania
| | - Bogdan I Bita
- 1Nano-Scale Structuring and Characterization Laboratory,National Institute for Research and Development in Microtechnologies,126A Erou Iancu Nicolae Street,077190 Bucharest,Romania
| | - Vasilica Tucureanu
- 3Laboratory for Micro- and Nanofluidics,National Institute for Research and Development in Microtechnologies,126A Erou Iancu Nicolae Street,077190 Bucharest,Romania
| | - Dan Vasilache
- 5Microwave Circuits and Devices Laboratory,Micromachined Structures,National Institute for Research and Development in Microtechnologies,126A Erou Iancu Nicolae Street,077190 Bucharest,Romania
| | - Melania A Banu
- 6Laboratory of Nanobiotechnology,National Institute for Research and Development in Microtechnologies,126A Erou Iancu Nicolae Street,077190 Bucharest,Romania
| | - Andrei M Avram
- 3Laboratory for Micro- and Nanofluidics,National Institute for Research and Development in Microtechnologies,126A Erou Iancu Nicolae Street,077190 Bucharest,Romania
| | - Raluca A Giurescu-Dumitrescu
- 8Disciplines of Dental Medicine Department, Faculty of Dental Medicine,Titu Maiorescu University,67A Gheorghe Petrascu Street,031593 Bucharest,Romania
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Gupta L, Aparna IN, Bhat S, Ginjupalli K. Effect of comonomer of methacrylic acid on flexural strength and adhesion of Staphylococcus aureus to heat polymerized poly (methyl methacrylate) resin: An in vitro study. J Indian Prosthodont Soc 2017; 17:149-155. [PMID: 28584416 PMCID: PMC5450892 DOI: 10.4103/jips.jips_257_16] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Accepted: 01/09/2017] [Indexed: 11/16/2022] Open
Abstract
Aims and Objective: The purpose of the present study was to evaluate and compare flexural strength and Staphylococcus aureus adhesion of heat-activated poly (methyl methacrylate [MMA]) resin modified with a comonomer of methacrylic acid (MAA) and MMA monomer. Materials and Methods: Comonomer preparation was done with the addition of varying concentration of MAA (0, 15, 20, and 25 wt %) to the MMA of conventional heat-activated denture base resin to prepare the specimens. Prepared specimens were stored in distilled water at 37°C for 1 day and 1 week before the evaluation of flexural strength and microbial adhesion. Flexural strength was measured using a universal testing machine at a crosshead speed for 2 mm/min (n = 10). Microbial adhesion (colony-forming unit [CFU]) was evaluated against S. aureus using a quadrant streaking method (n = 5). Data were subjected to one-way ANOVA, and the significant differences among the results were subjected to Tukey's HSD test. P < 0.05 was considered statistically significant. Results: Addition of MAA to the MMA monomer was found to significantly reduce the adhesion of S. aureus for all the groups. Reduction of CFU of S. aureus was found be more significant for Group 3 as compared to control, both at 1-day (P < 0.001) and 1-week (P < 0.002) storage in distilled water. However, no statistically significant changes in the flexural strength were observed with the addition of MAA at 1-day (P = 0.52) and 1-week (P = 0.88) time interval. Conclusion: Addition of MAA to conventional denture base resin reduced the microbial adhesion without significantly affecting the flexural strength.
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Affiliation(s)
- Lokendra Gupta
- Department of Prosthodontics and Crown and Bridge, Manipal College of Dental Sciences, Manipal, Karnataka, India
| | - I N Aparna
- Department of Prosthodontics and Crown and Bridge, Manipal College of Dental Sciences, Manipal, Karnataka, India
| | - Sujatha Bhat
- Department of Microbiology, Melaka Manipal Medical College, Manipal, Karnataka, India
| | - Kishore Ginjupalli
- Department of Dental Materials, Manipal College of Dental Sciences, Manipal, Karnataka, India
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Cost-effectiveness analysis of the single-implant mandibular overdenture versus conventional complete denture: study protocol for a randomized controlled trial. Trials 2016; 17:533. [PMID: 27814749 PMCID: PMC5097429 DOI: 10.1186/s13063-016-1646-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 10/05/2016] [Indexed: 12/03/2022] Open
Abstract
Background Preliminary clinical studies on the single-implant mandibular overdenture (SIMO) have reported favorable results as an alternative to the conventional complete dentures for rehabilitation of the edentulous mandible. Clinical and patient-reported outcomes were assessed but no evidence is available with respect to the cost-effectiveness of this treatment, which is particularly important to test whether the incremental cost associated with the implant treatment is justified facing the benefits from the intervention. Thus, the aim of this study is to assess the cost-effectiveness of single-implant mandibular overdentures. Methods/design This randomized clinical trial will include edentulous individuals who meet eligibility criteria. Participants will be randomized into one of the treatment groups: a conventional complete denture group or a single-implant mandibular overdenture group. Direct costs related to therapies in both groups will be identified, measured and valuated for 1 year after treatment. Oral health-related quality of life and satisfaction with the dentures will be the primary outcome variables. Incremental cost-effectiveness ratios will be estimated and graphically presented on cost-effectiveness planes. A Markov decision tree will be constructed to set out the consequences of the competing alternatives. Sensitivity analysis on the most important assumptions will be performed in order to assess the robustness of the model. Discussion This is the first trial-based cost-effectiveness study on single-implant mandibular overdentures. Specific challenges in designing the protocol are considered. The expected results are of high clinical relevance and may contribute to the decision-making process when choosing between different alternatives for the rehabilitation of the edentulous mandible. Trial registration ClinicalTrials.gov Identifier: NCT02710357, registered on 11 March 2016. Electronic supplementary material The online version of this article (doi:10.1186/s13063-016-1646-0) contains supplementary material, which is available to authorized users.
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Role of Berberine in the Treatment of Methicillin-Resistant Staphylococcus aureus Infections. Sci Rep 2016; 6:24748. [PMID: 27103062 PMCID: PMC4840435 DOI: 10.1038/srep24748] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 04/04/2016] [Indexed: 12/23/2022] Open
Abstract
Berberine is an isoquinoline alkaloid widely used in the treatment of microbial infections. Recent studies have shown that berberine can enhance the inhibitory efficacy of antibiotics against clinical multi-drug resistant isolates of methicillin-resistant Staphylococcus aureus (MRSA). However, the underlying mechanisms are poorly understood. Here, we demonstrated that sub-minimum inhibitory concentrations (MICs) of berberine exhibited no bactericidal activity against MRSA, but affected MRSA biofilm development in a dose dependent manner within the concentration ranging from 1 to 64 μg/mL. Further study indicated that berberine inhibited MRSA amyloid fibrils formation, which consist of phenol-soluble modulins (PSMs). Molecular dynamics simulation revealed that berberine could bind with the phenyl ring of Phe19 in PSMα2 through hydrophobic interaction. Collectively, berberine can inhibit MRSA biofilm formation via affecting PSMs’ aggregation into amyloid fibrils, and thereby enhance bactericidal activity of antibiotics. These findings will provide new insights into the multiple pharmacological properties of berberine in the treatment of microbial-generated amyloid involved diseases.
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Effectiveness of Chemical and Microwave Disinfection on Denture Biofilm Fungi and the Influence of Disinfection on Denture Base Adaptation. J Indian Prosthodont Soc 2015. [PMID: 26199488 DOI: 10.1007/s13191-014-0354-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
The aims of this study were to evaluate the effectiveness of six disinfection methods and the influence of these methods on the adaptation of maxillary dentures. Acrylic resin specimens contaminated with fungi were exposed to the following disinfection treatments: 1. microwave oven (900 W) at full power for 5 min (with soaking the specimen in 250 ml water), 2. microwave oven at medium power for 5 min (with soaking the specimen in 250 ml water), 3. sodium hypochlorite 5.25 % for 5 min, 4. diluted sodium hypochlorite 1:420 for 5 h, 5. Chlorhexidine gluconate for 5 h, 6. effervescent tablets for 15 min, 7. soaking in 250 ml tap water for 15 min. Colony forming units (CFUs) of remaining cells were counted and compared with t test (p ≤ 0.05). Dimensional stability was evaluated using aluminum die simulating the maxillary edentulous arch. Posterior palatal gaps were measured. Data were analyzed using one-way ANOVA test and t test (p ≤ 0.05). Microwave irradiation (at full or medium power) and sodium hypochlorite 5.25 % for 5 min were able to reduce the CFUs of fungi by more than 4 log10 whereas diluted sodium hypochlorite, chlorhexidine gluconate, and effervescent tablets did not achieve a reduction of >2.8, 2.68 and 1.66, respectively. For dimensional stability test, t test revealed significant difference between control group and the microwave at full power group (p = 0.000). Within the limits of this study, microwave oven at medium power and sodium hypochlorite (5.25 %) are effective and safe methods of disinfecting removable dentures.
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Zago CE, Silva S, Sanitá PV, Barbugli PA, Dias CMI, Lordello VB, Vergani CE. Dynamics of biofilm formation and the interaction between Candida albicans and methicillin-susceptible (MSSA) and -resistant Staphylococcus aureus (MRSA). PLoS One 2015; 10:e0123206. [PMID: 25875834 PMCID: PMC4395328 DOI: 10.1371/journal.pone.0123206] [Citation(s) in RCA: 98] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Accepted: 03/02/2015] [Indexed: 12/28/2022] Open
Abstract
Polymicrobial biofilms are an understudied and a clinically relevant problem. This study evaluates the interaction between C. albicans, and methicillin- susceptible (MSSA) and resistant (MRSA) S. aureus growing in single- and dual-species biofilms. Single and dual species adhesion (90 min) and biofilms (12, 24, and 48 h) were evaluated by complementary methods: counting colony-forming units (CFU mL-1), XTT-reduction, and crystal violet staining (CV). The secretion of hydrolytic enzymes by the 48 h biofilms was also evaluated using fluorimetric kits. Scanning electron microscopy (SEM) was used to assess biofilm structure. The results from quantification assays were compared using two-way ANOVAs with Tukey post-hoc tests, while data from enzymatic activities were analyzed by one-way Welch-ANOVA followed by Games-Howell post hoc test (α = 0.05). C. albicans, MSSA and MRSA were able to adhere and to form biofilm in both single or mixed cultures. In general, all microorganisms in both growth conditions showed a gradual increase in the number of cells and metabolic activity over time, reaching peak values between 12 h and 48 h (ρ<0.05). C. albicans single- and dual-biofilms had significantly higher total biomass values (ρ<0.05) than single biofilms of bacteria. Except for single MRSA biofilms, all microorganisms in both growth conditions secreted proteinase and phospholipase-C. SEM images revealed extensive adherence of bacteria to hyphal elements of C. albicans. C. albicans, MSSA, and MRSA can co-exist in biofilms without antagonism and in an apparent synergistic effect, with bacteria cells preferentially associated to C. albicans hyphal forms.
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Affiliation(s)
- Chaiene Evelin Zago
- Department of Dental Materials and Prosthodontics, Araraquara Dental School, UNESP—Univ Estadual Paulista. Araraquara, São Paulo, Brazil
| | - Sónia Silva
- IBB-Institute for Biotechnology and Bioengineering, Center of Biological Engineering, University of Minho, Braga, Portugal
| | - Paula Volpato Sanitá
- Department of Dental Materials and Prosthodontics, Araraquara Dental School, UNESP—Univ Estadual Paulista. Araraquara, São Paulo, Brazil
| | - Paula Aboud Barbugli
- Department of Dental Materials and Prosthodontics, Araraquara Dental School, UNESP—Univ Estadual Paulista. Araraquara, São Paulo, Brazil
| | - Carla Maria Improta Dias
- Department of Dental Materials and Prosthodontics, Araraquara Dental School, UNESP—Univ Estadual Paulista. Araraquara, São Paulo, Brazil
| | - Virgínia Barreto Lordello
- Department of Dental Materials and Prosthodontics, Araraquara Dental School, UNESP—Univ Estadual Paulista. Araraquara, São Paulo, Brazil
| | - Carlos Eduardo Vergani
- Department of Dental Materials and Prosthodontics, Araraquara Dental School, UNESP—Univ Estadual Paulista. Araraquara, São Paulo, Brazil
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Wagner DA, Pipko DJ. The effect of repeated microwave irradiation on the dimensional stability of a specific acrylic denture resin. J Prosthodont 2014; 24:25-31. [PMID: 25082075 DOI: 10.1111/jopr.12203] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/18/2014] [Indexed: 01/28/2023] Open
Abstract
PURPOSE To determine the dimensional stability of a poly(methyl methacrylate) (PMMA) acrylic resin when subjected to multiple sessions of repeated microwave irradiation at power settings of 700 and 420 W. MATERIALS AND METHODS Twenty standardized denture bases were fabricated using a PMMA resin. Points of measurement were marked on each denture base with a standardized template, and the distances between points were recorded using a digital microscope. The denture bases were randomly placed into two experimental groups of 10 bases each. Individual denture bases were placed into a glass beaker containing 200 ml of room temperature deionized water and then exposed to either 700 or 420 W of microwave radiation for 3 minutes. The denture bases were allowed to cool to room temperature, and measurements between points were recorded. This process was carried out for two microwave periods with measurements being completed after each period. The data were then analyzed for any significant changes in distances between points using a Student's t-test. RESULTS All denture bases experienced 1.0 to 2.0 mm or approximately 3% linear dimensional change after each period of microwaving. Results were significant with all t-tests having values of p < 0.05. CONCLUSION This report showed that the denture bases deformed significantly under experimental conditions at either 700 W for 3 minutes in 200 ml of water or 420 W for 3 minutes in 200 ml of water.
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Affiliation(s)
- David A Wagner
- Former Prosthodontic Resident, University of Pittsburgh, School of Dental Medicine, Pittsburgh, PA
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Altieri KT, Sanitá PV, Machado AL, Giampaolo ET, Pavarina AC, Jorge JH, Vergani CE. Eradication of a Mature Methicillin-Resistant Staphylococcus aureus (MRSA) Biofilm From Acrylic Surfaces. Braz Dent J 2013; 24:487-91. [DOI: 10.1590/0103-6440201302289] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2013] [Accepted: 09/14/2013] [Indexed: 11/22/2022] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) can grow as structured biofilm in different surfaces, including oral mucosa and denture surfaces. Such biofilms can be released into the oral fluids and aspirated, causing systemic infections such as aspiration pneumonia. This study evaluated the efficacy of two disinfectant solutions and microwave irradiation in disinfecting acrylic specimens contaminated with MRSA biofilm. Thirty-six acrylic specimens were made, sterilized and contaminated with MRSA (107 cfu/mL). After incubation (37 °C/48 h), the specimens were divided into 4 groups: not disinfected (positive control); soaking in 1% sodium hypochlorite for 10 min; soaking in 2% chlorhexidine gluconate for 10 min; and irradiating by microwave for 3 min at 650 W. The viability of cells was evaluated by XTT reduction method. All specimens from the positive control group showed biofilm formation after 48 h incubation. The mean absorbance value of the control specimens was 1.58 (OD at 492 nm). No evidence of biofilm formation was observed on specimens after the disinfection methods. Disinfection by soaking in 1% sodium hypochlorite and 2% chlorhexidine gluconate and irradiating by microwaves resulted in 100% reduction of MRSA biofilm metabolism. The use of chemical solutions and microwave irradiation was shown to be effective for eradicating mature MRSA biofilms on acrylic resin specimens.
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Silva MM, Mima EGDO, Colombo AL, Sanitá PV, Jorge JH, Massucato EMS, Vergani CE. Comparison of denture microwave disinfection and conventional antifungal therapy in the treatment of denture stomatitis: a randomized clinical study. Oral Surg Oral Med Oral Pathol Oral Radiol 2013; 114:469-79. [PMID: 22986242 DOI: 10.1016/j.oooo.2012.05.006] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2012] [Revised: 05/10/2012] [Accepted: 05/14/2012] [Indexed: 11/19/2022]
Abstract
OBJECTIVE The aim of this study was to compare the effectiveness of denture microwave disinfection and antifungal therapy on treatment of denture stomatitis. STUDY DESIGN Sixty denture wearers with denture stomatitis (3 groups; n = 20 each), were treated with nystatin or denture microwave disinfection (1 or 3 times/wk) for 14 days. Mycologic samples from palates and dentures were quantified and identified with the use of Chromagar, and clinical photographs of palates were taken. Microbiologic and clinical data were analyzed with the use of a series of statistical tests (α = .05). RESULTS Both treatments similarly reduced clinical signs of denture stomatitis and growth on palates and dentures at days 14 and 30 (P > .05). At sequential appointments, the predominant species (P < .01) isolated was C. albicans (range 98%-53%), followed by C. glabrata (range 22%-12%) and C. tropicalis (range 25%-7%). CONCLUSIONS Microwave disinfection, at once per week for 2 treatments, was as effective as topical antifungal therapy for treating denture stomatitis.
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Commercial mouthwashes are ineffective against oral MRSA biofilms. Oral Surg Oral Med Oral Pathol Oral Radiol 2013; 115:624-9. [DOI: 10.1016/j.oooo.2012.12.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Revised: 12/19/2012] [Accepted: 12/21/2012] [Indexed: 11/17/2022]
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Sharan S, Kavitha HR, Konde H, Kalahasti D. Effect of chemical disinfectant on the transverse strength of heat-polymerized acrylic resins subjected to mechanical and chemical polishing: an in vitro study. J Contemp Dent Pract 2012; 13:389-93. [PMID: 22918015 DOI: 10.5005/jp-journals-10024-1156] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
AIMS To evaluate the effect of chemical disinfectant on the transverse strength of heat-polymerized acrylic resins subjected to mechanical and chemical polishing. MATERIALS AND METHODS A total of 256 rectangular specimens (65 * 10 * 3 mm) 128 per resin (Lucitone-199 and Acralyn-H) were fabricated. One side of each specimen was not polished and the other was either mechanically (n = 96) or chemically (n = 96) polished and immersed for 10, 30 and 60 minutes in 2% alkaline glutaraldehyde. Mechanically polished (n = 32) and chemically polished (n = 32) control specimens were immersed only in distilled water. The transverse strength (N/mm(2)) was tested for failure in a universal testing machine, at a crosshead speed of 5 mm/min. Data were statistically analyzed using 2-way ANOVA and Student t-test. RESULTS chemical polishing resulted in significantly lower transverse strength values than mechanical polishing. Lucitone- 199 resin demonstrated the highest overall transverse strength for the materials tested. Heat-polymerized acrylic resins either mechanically or chemically polished, did not demonstrate significant changes in transverse strength during immersion in the disinfecting solution tested, regardless of time of immersion. CONCLUSION Lucitone-199 resin demonstrated the highest overall transverse strength for the materials tested and significantly stronger than Acralyn-H with either type of polishing following immersion in 2% alkaline glutaraldehyde. CLINICAL SIGNIFICANCE There is a concern that immersion in chemical solutions often used for cleansing and disinfection of prostheses may undermine the strength and structure of denture base resins. In this study it was observed that, the transverse strength of samples of Lucitone-199 was higher than that of the samples of Acralyn-H. The chances of fracture of the denture made of Lucitone-199 are less than that of dentures made of Acralyn-H. The chemically polished dentures may be more prone to fracture than mechanically polished dentures.
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Affiliation(s)
- Smitha Sharan
- Department of Prosthodontics, NSVK Sri Venkateshwara Dental College and Hospital, Bengaluru-560083, Karnataka, India.
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