Background:There is necessary of dry operating field for bonding of orthodontic brackets. The presence of moisture can alter the bond strength. Hence, the aim of the present study was to evaluate the shear bond strength of orthodontic brackets with different adhesives.Materials and Methods:In this in vitro study, a total of 100 orthodontically extracted premolars with sound crown structure were divided into 4 equal groups of different primers. Bonding on the buccal surface of all teeth was done after acid etching with upper premolar brackets using different primers followed by light curing. Shear bond strength was evaluated with or without salivary contamination with both adhesives. A shear force for deboning the bracket was done with universal testing machine. The debonded specimens were examined at ×10 magnification to check site of bond failure and remaining adhesive on tooth using adhesive remnant index (ARI). The obtained data were statistically evaluated using SPSS 20 for Windows (SPSS Inc., Chicago, IL, USA) using ANOVA, Kolmogorov–Smirnov, and Levene's test at the statistical significance of P < 0.05.Results:Transbond Plus showed higher shear bond strength of 8.92 MPa under dry and 5.65 MPa with saliva contamination over Transbond XT of 7.24 MPa under dry and 2.43 MPa with saliva contamination, respectively. Higher ARI score was found without contamination in both adhesives.Conclusion:Transbond Plus hydrophilic resin had good shear bond strength under both dry and contamination condition compared to hydrophobic Transbond XT resin material.

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Background: Studies in the past have assessed relation between airway and type of malocclusion and found no association between rhinomanometric measures of airway adequacy and type of malocclusion or craniofacial morphology. Hence, the present study was undertaken to test whether there is any association between pharyngeal airway and type of malocclusion. Methodology: The subjects were divided into 3 groups based on skeletal pattern with 20 subjects in each group: Group 1 with Class I skeletal pattern, Group 2 with Class II skeletal pattern, and Group 3 with Class III skeletal pattern. All the cephalograms were taken in natural head position. Results: There is no significant difference found in total nasopharyngeal area between 3 groups. However, aerial area was significantly reduced in Group 3 (398.4 mm2) than that of Group 2 (485.737 mm2) (P = 0.012). Whereas, significant reduction in adenoidal area was observed in Group 2 (184.021 mm2) when compared with that of Group 3 (286.183 mm2). Conclusion: There was no statistically significant relationship between different skeletal groups and nasopharyngeal soft-tissue characteristics, except for two measurements i.e. aerial and adenoidal area of Group 2 and Group 3.