Saad, Y., Abdelhamid, A., ElShabrawy, S. (2018). LABORATORY EVALUATION OF PRE-POLYMERIZED DENTURE BASE MATERIAL USED FOR CAD/CAM COMPLETE DENTURE MANUFACTURING. Alexandria Dental Journal, 43(3), 94-101. doi: 10.21608/adjalexu.2018.58006
Yusra M. Saad; Ahmed M. Abdelhamid; Sonia M. ElShabrawy. "LABORATORY EVALUATION OF PRE-POLYMERIZED DENTURE BASE MATERIAL USED FOR CAD/CAM COMPLETE DENTURE MANUFACTURING". Alexandria Dental Journal, 43, 3, 2018, 94-101. doi: 10.21608/adjalexu.2018.58006
Saad, Y., Abdelhamid, A., ElShabrawy, S. (2018). 'LABORATORY EVALUATION OF PRE-POLYMERIZED DENTURE BASE MATERIAL USED FOR CAD/CAM COMPLETE DENTURE MANUFACTURING', Alexandria Dental Journal, 43(3), pp. 94-101. doi: 10.21608/adjalexu.2018.58006
Saad, Y., Abdelhamid, A., ElShabrawy, S. LABORATORY EVALUATION OF PRE-POLYMERIZED DENTURE BASE MATERIAL USED FOR CAD/CAM COMPLETE DENTURE MANUFACTURING. Alexandria Dental Journal, 2018; 43(3): 94-101. doi: 10.21608/adjalexu.2018.58006
LABORATORY EVALUATION OF PRE-POLYMERIZED DENTURE BASE MATERIAL USED FOR CAD/CAM COMPLETE DENTURE MANUFACTURING
1BDS and Demonstrator, Removable prosthodontic department, Faculty of Dentistry, Benghazi University, Libya
2Professor of Prosthodontics, Faculty of Dentistry, Alexandria University, Egypt
3Professor and Head of Biomaterial, Faculty of Dentistry, Alexandria University, Egypt
Abstract
INTRODUCTION: CAD/CAM denture base materials are milled from pre-polymerized pucks of resin that are highly condensed. So, they provide no polymerization shrinkage eliminating its subsequent disadvantages. This technology offered improved fit, strength properties and more bio-hygienic denture bases compared with conventional processing of the denture base material. OBJECTIVES: The aim of the study was to evaluate the physico-mechanical properties of CAD/CAM denture base material and the effect of thermo-cycling on it compared with the conventional one. MATERIALS AND METHODS: The study was conducted on two parallel groups, divided according to the denture material used. Group (1) conventional PMMA (control group), group (II) CAD/CAM PMMA (study group) of 40 specimens each (16 for impact strength, 16 for flexural strength, 8 for surface roughness and grinded powder form both materials for residual monomer test). Each group was divided into 2 sub-groups: (A) No thermo-cycling and (B) Thermo-cycling, then subjected to 4 different tests, impact strength, flexural strength, surface roughness and residual monomer tests. Data were collected, tabulated and statistically analyzed. Significance level was set at 5%. Bar charts were used for graphical presentations. RESULTS: Our study revealed a highly statistically significant decrease in residual monomer of CAD/CAM PMMA material in both conditions before and after thermo-cycling when compared to conventional PMMA material, which therefore leads to enhanced impact strength and significantly reduced surface roughness after heat treatment. On the other hand, also a highly significant reduction of its flexural strength after thermocycling has been observed. CONCLUSIONS: CAD/CAM dentures with lower amount of methacrylate monomer exhibit more favourable physico-mechanical properties and they have a long-term biocompatibility even with thermal changes making them a more satisfactory as a denture base material for edentulous patients.
Chand P, Patel CB, Singh BP, Singh RD, Singh K. Mechanical properties of denture base resins: An evaluation. Indian J Dent Res. 2011;22:180.
Darber UR, Guggett R, Harrison A. Denture fracture A survey. Br Dent J. 1994;176:342-5.
Kohli S, Bhatia S. Flexural properties of polyamide versus injection-molded poly methyl methacrylate denture base materials. Eur J Prosthodont. 2013;1:56-60.
Doğan OM, Bolayır G, Keskin S, Doğan A, Bek B. The evaluation of some flexural properties of a denture base resin reinforced with various aesthetic fibers. J Mater Sci Mater Med. 2008;19:2343-9.
Miyazaki T, Hotta Y, Kunii J, Kuriyama S, Tamaki Y. A review of dental CAD/CAM: current status and future perspectives from 20 years of experience. Dent Mater J. 2009;28:44-56.
Kattadiyil MT, Goodacre CJ. CAD/CAM technology: application to complete dentures. Loma Linda Univ Dent 2012; 23: 16-23.
Wiley J. Clinical Application of Digital Dental technology. USA: John Wiley & Sons, Inc.; 2015. 108-10.
Daniel W. Biostatistics. A foundation for analysis in the health science. 6th ed. NY: John Wiley and sons, Inc; 1995.
Rossomando KJ, Wendt SL. Thermocycling and dwell times in microleakage evaluation for bonded restorations. Dent Mater 1995; 11: 47-51.
ISO 179-2:1997, Plastics – Determination of Charpy impact properties – Part 2: Instrumented impact test, ISO/TC 61/SC 2nd ed. Switzerland: International Standards Organization, 2010.
Rahn AO. Heartwell CM. Textbook of complete dentures. Laboratory procedures. 5th ed. USA: Williams & Wilkins,1993:375-84.
Abdulwahhab SS. High-impact strength acrylic denture base material processed by autoclave. J Prosthodont Res. 2013;57:288-93.
Revised American Dental Association Specification no.12 for denture base polymers. J Am Dent Assoc 1975; 90: 451-8.
Célia M, Morgana N, Machado C. Surface roughness of acrylic resins processed by microwave energy and polished by mechanical and chemical process. Braz J Oral Sci. 2006;5:977-981.
Al–Ali AA, Sheet OA, Taqa AA. The Effect of Different Curing Techniques on the Degree of Bond Conversion for Different Types of Acrylic Resin Materials. Al–Rafidain Dent J. 2013;13:351-7.
He L, Liang J, Zhao X, Li W, Luo H. Preparation and comparative evaluation of well-defined fluorinated acrylic copolymer latex and solution for ancient stone protection. Progr Org Coat. 2010;69:352-8.
Nomoto R, Asada M, Mccabe JF, Hirano S. Light exposure required for optimum conversion of light activated resin systems. Dent Mater. 2006;22:1135-42.
Kotz S, Balakrishnan N, Read CB, Vidakovic B. Encyclopedia of statistical sciences. 2nd ed. Hoboken, New Jersey: Wiley-Interscience; 2006.
Akin H, Tugut F, Polat ZA. Vitro comparison of the cytotoxicity and water sorption of two different denture base systems. J Prosthodont. 2015;24:152-5.
Matsuo H, Suenaga H, Takahashi M, Suzuki O, Sasaki K, Takahashi N. Deterioration of poly methyl methacrylate dentures in the oral cavity. Dent Mater J. 2015;34:234-9.
Rashid H, Sheikh Z, Vohra F. Allergic effects of the residual monomer used in denture base acrylic resins. Eur J Dent. 2015;9:614-9.
Infante L, Yilmaz B. Fabricating complete dentures with CAD/CAM technology. J Prosthet Dent. 2014;111:351-5.
Kattadiyil T, Goodacre J. CAD/CAM technology: application to complete dentures. Loma Linda Univ Dent. 2012;23:16-23.
Murakami N, Wakabayashi N, Matsushima R, Kishida A, Igarashi Y. Effect of high-pressure polymerization on mechanical properties of PMMA denture base resin. J Mech Behav Biomed Mater. 2013;20:98-104
Steinmassl PA, Wiedemair V, Huck CH, Klaunzer F, Steinmassl O, Grunert I, et al. Do CAD/CAM dentures really release less monomer than conventional dentures? Clin Oral Invest. 2017;21:1697-705.
Al-Ameer SS. Effect of thermocycling on some mechanical properties of polyamide hypoallergenic denture base material (comparative study). Scientific J. 2012; 24: 25-30.
Arita T, Kayama Y, Ohno K, Tsujii Y, Fukuda T. High pressure atom transfer radical polymerization of methyl methacrylate for well-defined ultrahigh molecular-weight polymers. Polymer. 2008;49:2426-9.
Gungor H, Gundogdu M, Alkurt M, Duymus Z. Effect of polymerization cycles on flexural strengths and microhardness of different denture base materials. Dent Mater J. 2017;36:168-73.
Morgan TD, Wilson M. The effects of surface roughness and type of denture acrylic on biofilm formation by Streptococcus oralis in constant depth film fermentor. J Appl Microbiol. 2001;91:47-53.
Finoti LS, Machado AL, Chaves CA, Pavarina AC, Vergani CE. Effect of long-term water immersion on the fracture toughness of denture base and reline resins. Gerodontology. 2012; 29:858-64.
Roscaa B, Ramalho S, Fernandes J, Portugal J. Reparability of two different CAD/CAM polymer materials using a light-cured composite and universal adhesives. Rev Port Estomatol Med Dent Cir Maxillofac. 2016;57:189-96.
Milena K, Nebojša K, Ljubisa N, Vesna N, Stevo N, Ivan K, et al. The influence of residual monomer reduction in quality of resin materials stomatoprotetskih. Hem Ind. 2011;65:171-77.
Tang M, Nguyen J, Sadoun M, Dorin Ruse N. HPLC Analysis of Monomer Release from Conventionally and High Temperature High-Pressure Polymerised Urethane Dimethacrylate Intended for Biomedical Applications. J Chromatograph Separat Techniq. 2014;5:227