Evaluation of enamel surface after orthodontic debonding and cleanup using different procedures: An in vitro study

Objectives: The purpose of this in vitro study was to evaluate and compare the efficiency of four protocols of adhesive remnant removal and polishing after bracket debonding on enamel surfaces using scanning electron microscope (SEM) and to compare the time spent to remove resin remnants. Materials and Methods: The present study was a comparative study, in which brackets were bonded on forty freshly extracted human premolar teeth. They were debonded after 24 h and removal of remnant adhesive to as close as possible to the original condition using tungsten carbide burs (TCBs) (30 flutted) with low-speed contra-angle handpiece, Super Snap ® discs (course, medium, fine, and superfine), TCB + Brownie and Greenie (BG) polishers, and TCB + Super Snap ® discs. The surfaces were evaluated under SEM and graded according to the modified surface roughness index. Time taken to remove the residual adhesive was recorded using a stopwatch. Results were subjected to statistical analysis. Results: Super Snap ® discs showed a smooth surface with minimal scratches. TCB resulted in an irregular enamel surface in SEM evaluation, showing horizontal scars with a consistent pattern and left remnants on the enamel surfaces. TCB followed by Super Snap ® discs produced some scratches on the enamel surface. The mean time was significantly higher in Group I than the other three groups (P = 0.000). The mean time was significantly lower in Group II than the other three groups (P = 0.000). TCB took the least amount of time followed by TCB + stainless steel and TCB + BG polishers. Conclusion: Enamel surface was restored as close to the original using the Super Snap ® discs. TCB produced a very rough surface, but it is an efficient and least time-consuming procedure. The resultant enamel surface with enamel scars needs to be finished by other polishing techniques after bulk removal using TCB as the sequential use of Super Snap ® discs and polishers is less aggressive in removing residual bonding resin and results in apparently better surface finish causing less damage to the enamel

Evaluation of mandibular morphology in different facial types

The purpose of this study was to evaluate mandibular morphology in different facial types using various parameters. This study was conducted on lateral cephalograms of a total of 110 subjects, which included 55 males and 55 females between the age of 18-25 years having a mean of 22.3 years for males and 21.5 years for females. The sample was divided into normodivergent, hypodivergent, and hyperdivergent subgroups based on Jarabak's ratio. Symphysis height, depth, ratio (height/depth) and angle, antegonial notch depth, ramal height and width, mandibular depth, upper, lower, and total gonial angle, and mandibular arc angle were analyzed statistically and graphically. It was found that the mandible with the vertical growth pattern was associated with a symphysis with large height, small depth, large ratio, small angle, decreased ramus height and width, smaller mandibular depth, increased gonial angle, and decreased mandibular arc angle in contrast to mandible with a horizontal growth pattern. Sexual dichotomy was found with mean symphysis height and depth in the female sample being smaller than in the male sample, but symphysis ratio was larger in the female sample; males having greater ramus height and width, mandibular depth than females. The mandible seemed to have retained its infantile characteristics with all its processes underdeveloped in hyperdivergent group