Peel bond strength of resilient liner modified by the addition of antimicrobial agents to denture base acrylic resin

In order to prolong the clinical longevity of resilient denture relining materials and reduce plaque accumulation, incorporation of antimicrobial agents into these materials has been proposed. However, this addition may affect their properties. OBJECTIVE: This study evaluated the effect of the addition of antimicrobial agents into one soft liner (Soft Confort, Dencril) on its peel bond strength to one denture base (QC 20, Dentsply). MATERIAL AND METHODS: Acrylic specimens (n=9) were made (75x10x3 mm) and stored in distilled water at 37ºC for 48 h. The drug powder concentrations (nystatin 500,000U - G2; nystatin 1,000,000U - G3; miconazole 125 mg - G4; miconazole 250 mg - G5; ketoconazole 100 mg - G6; ketoconazole 200 mg - G7; chlorhexidine diacetate 5% - G8; and 10% chlorhexidine diacetate - G9) were blended with the soft liner powder before the addition of the soft liner liquid. A group (G1) without any drug incorporation was used as control. Specimens (n=9) (75x10x6 mm) were plasticized according to the manufacturers' instructions and stored in distilled water at 37ºC for 24 h. Relined specimens were then submitted to a 180-degree peel test at a crosshead speed of 10 mm/min. Data (MPa) were analyzed by analysis of variance (α=0.05) and the failure modes were visually classified. RESULTS: No significant difference was found among experimental groups (p=0.148). Cohesive failure located within the resilient material was predominantly observed in all tested groups. CONCLUSIONS: Peel bond strength between the denture base and the modified soft liner was not affected by the addition of antimicrobial agents.

Reembasamento em prótese total: material resiliente versus material rígido / Rebasing in total prosthesis: resiliente material versus rigid material

A reabsorção óssea do rebordo alveolar é um processo crônico e irreversível. Com o objetivode minimizar estas alterações, tem-se indicado o reembasamento imediato ou mediato das próteses removíveis. Existem estudos que demonstram que este procedimento traz maior qualidade de uso aos pacientes, pois promove uma adaptação mais satisfatória das mesmas com a mucosa. O objetivo deste artigo é comparar as indicações, vantagens e limitações dos materiais, resilientes e rígidos, indicados para o reembasamento imediato de próteses removíveis em consultório, através de dois casos clínicos. Após o acompanhamento destes casos clínicos, pode-se concluir que para obtenção do sucesso do reembasamento é importante que se respeite a indicação clínica, as propriedades físicas e mecânicas de cada material, bem como a proservação do comportamento do material, através de um rigoroso controle clínico. Também que os reembasadores rígidos podem ser utilizados por um maior período em relação aos resilientes, os quais devido às suas limitações devem ser utilizados apenas em condições transitórias.

The alveolar bone resorption is a cronic and irreversible processo In order to minimize thesechanges, it has been indicated the mediate or immediate relining of dentures. Studies have shown that the procedure for rebasing of dentures brings higher quality of use to patients, as this will promote a more satisfying adaptation of the prosthesis with the mucosa. The aim of this paper is to compare the indications, advantages and limitations of relíning materiais, resilient and hard, in office by two clinical cases. After the clinical monitoring of these cases, it can be concluded that to obtain the success of the relining is important to respect the indication, the physical and mechanical prerties of each material, as well as preservation the behavior of the material, through a rigorous clinical control. Also the hard reline can be used for a longer period compared to resilient, which due to their limitations should only be used in transient conditions.