Sumit Gandhi

Influence of symmetric and asymmetric alterations of maxillary canine gingival margin on the perception of smile esthetics among orthodontists, dentists, and laypersons

Introduction: Esthetics is one of the major concerns among people seeking orthodontic treatment, and its perception varies from person to person. Our objective was to determine the differences in the perception of smile esthetics among orthodontists, general dentists, and laypersons with respect to alteration in the maxillary canine gingival margin in close-up smile analyses. Materials and Methods: Close-up photograph of an ideal Indian female smile was selected. The images were digitally altered to create symmetrical images with the gingival margin levels of maxillary canine matching the central incisors. Twelve alterations were created in the gingival margin of the canine with discrepancies of 1, 2, and 3 mm in relation to the most superior point on the labial gingival margin of patients central incisor and divided under four groups. Finally, close-up images of the smile were assessed by orthodontist, general dentist, and layperson who indicated the level of attractiveness of each smile on a visual analogue score. The data collected were then statistically analyzed by one-way analysis of variance followed by Newman–Keuls range test. Results: Most evaluators considered all the three components, i.e., lips, teeth, and gingiva while assessing the smiles attractiveness. Statistically significant differences were observed between different evaluator groups when considering bilateral increase in crown height by 2 and 3 mm. The perceptions of asymmetries in the gingival margin levels of the maxillary canines were 1.0 mm for orthodontists and 2.0 mm for laypersons. Conclusion: The result of this study suggested that the orthodontists were more critical than dentist and layperson in evaluating smile esthetics.

Bimaxillary protrusion trait in the Indian population: A cephalometric study of the morphological features and treatment considerations

Abstract Purpose The orthodontic literature is discordant with the diagnosis of bimaxillary protrusion with no single anatomic answer and the anomaly has been referred in the literature with protean characteristics. The trait denotes a particular facial configuration and its cephalometric representation in certain ethnic and racial groups revealed a mixed pattern with individual variations. The present study was aimed at analyzing the dento-skeletal characteristics of bimaxillary protrusion in a sample of Indian men and women. Materials and methods Forty-six Indian subjects (28 women and 18 men; 19 ± 3.6 years of age) with Class I malocclusion and interincisal angle ≤110°, who attended orthodontic clinics for a comprehensive fixed orthodontic treatment were included for the study. The lateral films were hand traced and 27 parameters were measured. The data were imported to SPSS version 13 US package and statistical manipulation included means, standard deviation, and coefficient of variation (%). Male and female data were compared by Students t-test (unpaired). Correlation and regression analysis were performed to assess any relationship between different parameters. Results There was a marked increase in proclination of the maxillary incisors both to the maxillary plane (125.3 ± 5.7°), the NA line (35.1 ± 5.0°) and to sella–nasion (117.7 ± 5.5°). The positional relationship of the mandible to the maxilla with reference to the cranial base was within the normal limits (ANB = 3.1 ± 1.3°) and the skeletal pattern was Class I. The effective lengths of maxilla and mandible did not correlate significantly with sagittal skeletal discrepancy. Conclusion Unlike in other ethnic and racial groups, bimaxillary protrusion in Indian subjects is likely a bidental protrusion over normal dento-alveolar bases. The skeletal characteristics suggested a normal relationship of the functional components of the face. The condition could be treated successfully with orthodontic mechanotherapy alone.

The effect of pre-etching with 37% orthophosphoric acid on the shear bond strength of orthodontic brackets bonded using self-etching primer-adhesive system

Objectives: The purpose of this study was to compare the effect of pre-etching with 37% orthophosphoric acid on the shear bond strength (SBS) of orthodontic brackets bonded using self-etching primer (SEP). Materials and Methods: Two hundred freshly extracted human premolars were divided randomly into two groups based on pre-etching with 37% orthophosphoric acid: Group 1 (control, n = 50) without pre-etching and Group 2 (experimental, n = 150) with pre-etching. Group 2 was further divided into three sub groups 2a, 2b, and 2c with 50 teeth each and was first pre-etched with 37% orthophosphoric acid for 10, 30, and 60 s, respectively. Brackets were bonded on the teeth in both the groups using SEP and light cure adhesive. The SBS were determined using universal testing machine. The comparison of SBS was done using one-way analysis of variance and Tukey′s honest significant difference test. Results: The SBS of experimental Group 2 was significantly higher than the control Group 1 (p < 0.0001). Further, the SBS of Group 2a was highest, followed by Group 2b and 2c (p < 0.0001). Conclusion: It was found that pre-etching for 10 s prior to application of SEP-adhesive system increases the SBS of orthodontic brackets.

Simultaneous eruption of an impacted premolar due to traction applied on adjacent impacted tooth – what and where is the connection?

The mechanism of tooth eruption and the origin of eruptive forces are still controversial topics. Biological control underlying the eruption phenomenon is yet to be fully elucidated. This article reports a clinical observation that could have been overlooked in the literature. Eruption of an impacted first premolar was noted inadvertently subsequent to an applied traction to the adjacent impacted second premolar in a 47-yearold maie subject. A quest to the ongoing controversy of eruption is raised and hypotheses formulated.