Adaptation of complete denture bases submitted to chemical polishing.
OBJECTIVE
This study evaluated the effect of chemical polishing on the internal adaptation of complete denture bases fabricated with Veracril® resin and polymerized by either the conventional (C) or microwave (M) techniques.


METHODS
Six groups (n=6/group) were tested: 1) C + no polishing (CO); 2) C + chemical polishing (CQ); 3) C + immersion in hot water at 75ºC (CW); 4) M + no polishing (MO); 5) M + chemical polishing (MQ); and 6) M + immersion in hot water at 75ºC (MW). Internal adaptation immediately after the polishing treatment and after 30 days of storage in water at 37ºC was evaluated by weighing a vinyl polysiloxane film reproducing the gap between resin base and metallic master model, using a precision scale. Data were analyzed by ANOVA and Tukey test and paired Student's t test, at a significance level of 0.05.


RESULTS
No significant difference in immediate adaptation was found as a function of technique, polishing treatment, or interaction of technique/polishing. After 30 days, adaptation means (g) were: CO=2.46±0.32 a; CQ=3.40±0.23 d; CW=3.14±0.22 c; MO=3.23±0.37 c, d; MQ=3.41±0.47 d; MW=2.81±0.33 b (means followed by different letters are statistically different at alpha=0.05). All groups but group CO had significant increase of misfit over the tested period.


CONCLUSIONS
The present results suggest that Veracril® resin denture bases submitted to chemical polishing had decrease of internal adaptation in 30 days, although immediate adaptation was not affected.
Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, RS, Brazil.
Márcia
M
Gomes
Josué Ricardo
JR
Broilo
Luiz Fernando
LF
Walber
Paulo César Armani
PC
Maccari
Rosemary Sadami Arai
RS
Shinkai