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Introduction The aim of this study was to establish a new cephalometric parameter, named the Dhaval—Rohan angle (DR), to assess the vertical skeletal patterns on a lateral cephalogram with accuracy and reproducibility. Materials and methods One hundred and twenty pretreatment lateral cephalograms of the patients visiting the department of orthodontics and dentofacial orthopedics for treatment were obtained and divided into three groups. i.e., horizontal growth pattern, average growth pattern, and vertical growth pattern cases based on the routinely used cephalometric parameters; FMA, SN-GoGn, Y-axis angle and Jarabak ratio. This angle uses three skeletal landmarks, the point C (center of the condyle), point M (midpoint of premaxilla), and point G (center of the largest circle that is tangent to the internal inferior, anterior, and posterior surfaces of the mandibular symphysis). Results The one-way analysis of variance (ANOVA) test showed that the three groups studied were not the same for DR angle and the post hoc Tukey test found the groups to be significantly different. According to the Student's t-test, there was no statistically significant difference in mean values of DR angle between males and females. Conclusion Cephalometric evaluation of young adults shows that the DR angle below 28.5° indicates a horizontal growth pattern, between 28.5 and 32.5° indicate an average growth pattern and above 32.5° indicate a vertical growth pattern. How to cite this article Lekhadia DR, Rai R, Hegde N, Hegde G, Sorake A, Kumar A. Assessment of Vertical Skeletal Patterns using a New Cephalometric Parameter: The Dhaval—Rohan Angle. J Postgrad Med Edu Res 2017;51(1):7-11.

Aim:To evaluate the shear bond strength of orthodontic lingual bracket systems bonded to extracted premolar teeth (Reliance self-etching primer, Clearfil Protect Bond) and self-etching primer (Clearfil SE Bond) Materials and methods:A total of 160 extracted human first premolars were selected and divided into four groups of 10 for each bracket system to be used with four different primers. Each sample was then embedded in an acrylic block, till the coronal portion. Instron testing machine model LR LOYD 50 K was used for testing the shear bond strength. Results:The results obtained, suggested that all the primers had clinically acceptable shear bond strength with all the bracket system considered in the study. However, there were statistically significant differences in the shear bond strength in intergroup comparisons. Conclusion:The Reliance Self-Etching primer showed the highest bond strength with Alias lingual bracket system by Ormco, followed by clearfil protect bond, clearfil SE bond, and transbond, with the Alias lingual bracket system in the same order. Clinical significance:This study was initiated to understand the shear bond strength of self-etching primer and its efficacy over the conventional primer, which will be of use to the clinician while selecting the primer for bonding of the bracket systems and overcome debonding of brackets encountered during the treatment progress.

Aim: To compare and contrast the shear bond strength and adhesive remnant index scores of different Self ligating brackets. Materials and methods: A total of 75 extracted human first premolars were selected and divided into 3 groups of 25 for each bracket system. Each sample was then embedded in an acrylic block, till the coronal portion. Instron testing machine model LR LOYD 50 K was used for testing the shear bond strength. SBS values and adhesive failure rates were recorded. Results: All the bracket systems considered in the study demonstrated and clinically adequate Shear bond strength. Among the three groups, Damon Q gave the least remnant index score followed by SmartClip and BioQuick. Conclusion: The highest bond strength and the least remnant index score were obtained from Damon Q system, followed by Smartclip and BioQuick in the same order.

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