ABSTRACT
INTRODUCTION: Oral rehabilitation with removable dentures (RDs) is still a viable choice for the edentulous population. Fostering students' confidence in prosthodontic procedures should be a major concern in dental schools. This study has three purposes: (a) to measure the self-reported confidence levels of undergraduate dental students when performing removable prosthodontic treatments; (b) to evaluate the students' perceived quality of removable prosthodontics education; and (c) to assess the students' suggestions to improve removable prosthodontics education. MATERIALS AND METHODS: An anonymous questionnaire was delivered to third-, fourth- and fifth-year students of the Faculty of Dental Medicine of the University of Porto (FMDUP) (n = 176). Data from quantitative questions were statistically analysed with IBM SPSS Statistics for Windows (V.24.0), whilst qualitative data were clustered into topics and analysed in Excel. RESULTS: With a 100% response rate, most students felt "confident" and "very confident" in RD clinical procedures. Overall, the 5th-year students had higher confidence than 4th-year ones, except when surveying diagnostic casts. Our findings also revealed that students considered the removable prosthodontics education "Good" and "Very good," and their main suggestions were related to increasing the time allocated to clinical practice. CONCLUSIONS: Students' confidence in carrying out removable prosthodontic procedures grew as they progressed through the course. Overall, the students' evaluation of the quality of prosthodontics education was positive, and their main suggestion to improve their confidence levels was increasing the clinical experience.
Subject(s)
Prosthodontics , Students, Dental , Dentists , Education, Dental , Faculty , Faculty, Dental , HumansABSTRACT
Purpose: To analyze the stress distribution on a cantilever-fixed partial denture after simulation of maximum mastication loads in order to optimize its design. Methods: A cantilever-fixed partial denture framework was designed in the CAD-CAM system Everest®Kavo v2.0 using two materials, titanium and zirconium, with connectors of 5.28 mm² and 9.05 mm², respectively. A finite element model was built for stress analysis using simulations of mastication load. Results: For zirconia, only the molar cantilever with the smaller connector area and a 0.5-mm fillet exceeded the considered threshold resistance value of 575 MPa. All the other designs yielded resistances below this value. For titanium, only cantilevers with 9.05 mm² connector area and fillets of 1 or 1.4 mm presented stress values inferior to titanium yield strengh. Conclusion: Within the limitations of this study, it can be concluded that titanium cantilever-fixed partial denture frameworks with a 5.28 mm² connector area cannot support maximum mastication loads; frameworks of this material require larger connectors with fillets introduced in the gingival embrasure. Zirconia, however, supports maximum bite forces in most situations with both molar and premolar design cantilevers. Precaution should be taken when dealing with smaller connectors of 5.28 mm².
Objetivo: Analisar a distribuição de tensões em próteses parciais fixas em cantilever após aplicação de cargas simuladoras da mastigação, de forma a otimizar o seu desenho. Metodologia: Obteve-se a infra-estrutura de uma prótese parcial fixa em cantilever no sistema CAD-CAM Everest®Kavo v2.0, considerando dois materiais: titânio e zircônia, com conectores de 5,28 mm² e 9,05 mm², respectivamente. Gerou-se um modelo de elementos finitos, onde foram efetuadas análises de tensões com cargas simuladoras da mastigação. Resultados: Para zircônia, apenas o cantilever molar com área de conector mais reduzida, e concordância de 0,5 mm, excedeu o valor de resistência 575 MPa. Para o titânio, apenas o cantilever de 9,05 mm², com concordâncias de 1 e 1,4 mm, apresentou valores inferiores à tensão do titânio. Conclusão: Dentro das limitações deste estudo pode-se concluir que as infra-estruturas de titânio em cantilever não suportam cargas mastigatórias máximas com uma área de conector de 5,28 mm² e requerem conectores de áreas superiores, com concordâncias introduzidas na embrasura gengival. A zircônia geralmente suporta forças mastigatórias máximas com cantilever molar ou pré-molar. Deve-se ter precaução quando a área dos conectores é reduzida para 5,28 mm².
