Study of the tooth movement in complete denturees processed by different polymerazation cyclews and post-pressing times / Estudo do deslocamento dental linear em proteses totais processadas em diferentes ciclos de polimerização e tempos pós-prensagem

AUTOR(ES)
DATA DE PUBLICAÇÃO

2008

RESUMO

This study verified the tooth movement in maxillary complete dentures submitted to different polymerization cycles and post-pressing times. Forty maxillary complete dentures fabricated with Classico, QC-20, and Onda-Cryl acrylic resins, were randomly assigned into 8 groups (n=5) according to the polymerization cycles (long cycle in water bath (control-group), fast cycle in boiling water, and microwave cycle) and the post-pressing time (immediate and after 6 hours). The wax pattern was made using a semi-adjustable articulator having a mandibular dentate cast as a reference. Metallic referential pins were placed on the incisal border of the central incisors, vestibular cusp of the first premolars, and the mesio-vestibular cusp of the second molars. The PMD-PME (right premolar to left premolar), MD-ME (right molar to left molar) transversal distances and RI-RM (right incisor to right molar) and LI-LM (left incisor to left molar) anteroposterior distances were measured before and after the complete dentures processing with a linear optical microscope (Olympus Optical Co., Tokyo, Japan) with an accuracy of 0.0005mm. All acrylic resins were proportioned and manipulated following the manufacturer?s directions. Classico and QC-20 acrylic resins were submitted to the conventional water bath curing at 74ºC for 9 hours or to boiling water curing for 20 minutes respectively. Onda-Cryl acrylic resin was processed by microwave energy cycle for 3 minutes at 35%, 4 minutes at 0%, and 3 minutes at 65% power of the microwave oven. Collected data were submitted to the ANOVA and Tukey test at 5% of significance. All distances showed tooth movement; however, that was not statistically significant (5%) before and after processing for all polymerization cycles analyzed. The microwave polymerization cycle was statisticaly comparable with the conventional one in water bath (control group) considering the magnitude of tooth movement. The 6-hour post-pressing had no advantage in reducing the magnitude of tooth movement in relation to the immediate polymerization for most of the distances evaluated. It was concluded that the changes were not similar being influenced by the polymerization cycles, post-pressing time, and distance among teeth

ASSUNTO(S)

movimentação dentaria artificial acrylic resins teeth tooth movement protese dentaria resinas acrilicas

ACESSO AO ARTIGO

Documentos Relacionados