ABSTRACT
AIM: The purpose of this study was to evaluate the effectiveness of three desensitizing agents on dentinal tubule obliteration and their durability in use on the dentinal tubules. MATERIALS AND METHODS: Sixty specimens were obtained from 30 extracted sound human maxillary first premolars. Each tooth was mesiodistally sectioned to obtain 30 buccal and 30 lingual surfaces, and enamel was removed in order to simulate hypersensitive dentin. Specimens were divided into four groups with 15 specimens each. Group 1 samples were immersed in artificial saliva, Group 2 samples were coated with Vivasens, Group 3 samples were coated with VOCO Admira Protect, and Group 4 samples were coated with Neo Active Apatite suspension. These specimens were examined under scanning electron microscope (SEM) to find out the occluding ability of the respective products. The specimens were brushed to find out their durability for 1 week and 1 month and were examined under SEM. STATISTICAL ANALYSIS: The results were statistically analyzed by analysis of variance (ANOVA) and Tukey's test. RESULTS: Group 1 differed significantly from the Vivasens, Admira, and Neo Active Apatite groups at 5% level of significance (P < 0.05). The Vivasens group differed significantly from the Admira and Neo Active Apatite groups at 5% level of significance (P < 0.05). CONCLUSION: The Ormocer-based Admira Protect showed the best results.
ABSTRACT
AIM: To evaluate and compare the frictional resistance produced by Super Slick modules during sliding with four different types of brackets and four ligature types both in conventional and figure-of-8 ligation method with saliva as lubricant. MATERIALS AND METHODS: The frictional resistance was evaluated by using four different ligatures on 0.019" × 0.025" stainless steel (SS) archwires using four different brackets using an universal testing machine with unstimulated saliva as a lubricant. Mean and SD values were calculated. Data was statistically analyzed using analysis of variance ANOVA with post hoc test. RESULTS: The results showed that self-ligating brackets produced least frictional forces. Among all other tested combinations,Tefon-coated SS ligatures in ceramic with metal slot brackets produced least coefficient of static and kinetic friction and full ceramic brackets ligated with Super Slick elastomeric modules demonstrated the highest, with other combinations falling in between. CONCLUSION: Super Slick elastomeric modules, produced highest coefficient of both static and kinetic friction with the conventional and figure-of-8 ligation technique even in wet conditions using natural fresh human saliva. CLINICAL SIGNIFICANCE: Both static and kinetic frictional resistance play an important role during sliding mechanics. Various factors have been attributed for friction. However, bracket type, archwire material, type of ligature and method of ligation are important variables. Recently polymeric coated slick elastomeric modules were introduced with the claim that they produce very low frictional forces in wet condition. Contrary to the claim made by the manufacturers of Super Slick elastomeric modules, they produced highest coefficient of both static and kinetic friction with the conventional and figure-of-8 ligation technique.
