• The Journal of Advanced Prosthodontics
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• v.5 no.1
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• pp.9-15
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• 2013

PURPOSE. The purpose of this study was to determine accurately the part of the tragus to be used to form the Ala-Tragal line or Camper's line in orthognathic profile patients. MATERIALS AND METHODS. 150 dentate subjects with age of 18-40 years with orthognathic profile were sampled. Life-size lateral digital photographs of the face with fox plane were taken in natural head position. Different angles between Eye-Ear plane and occlusal plane ($OT_1$-OP), Eye-Ear plane and ala-superior border of tragus ($OT_1-AT_1$), Eye-Ear plane and ala-middle border of tragus ($OT_1-AT_2$) and Eye-Ear plane and ala-inferior border of tragus ($OT_1-AT_3$) were calculated using computer software package, AutoCAD 2004. From the three angles formed by the Eye-ear plane ($OT_1$ or FH plane) and the ala-tragal lines, the one closest to the angle formed between Eye-Ear plane ($OT_1$) and occlusal plane (OP) was used to determine the occlusal plane of orientation. The obtained results were subjected to ANOVA F test, Tukey's Honestly significant difference test, followed by Karl Pearson coefficient of correlation test. P values of less than 0.05 were taken as statistically significant. RESULTS. The mean of base line angle i.e. $OT_1$-OP angle ($11.96{\pm}4.36$) was found to be close to $OT_1-AT_2$ angle ($13.67{\pm}1.93$) and $OT_1-AT_3$ angle ($10.31{\pm}2.03$), but $OT_1$-OP angle was found to be more closer to $OT_1-AT_3$ angle. Comparison of mean angles showed that $OT_1$-OP angle in both males (11.68) and females (12.51) is close to $OT_1-AT_3$ angle (males- 11.01, females- 11.95). CONCLUSION. The line joining from ala to the lower border of the tragus was parallel to the occlusal plane in 53.3% of the subjects. There was no influence of the sex on the level of occlusal plane.

• Restorative Dentistry and Endodontics
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• v.30 no.2
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• pp.112-120
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• 2005

This study was done to evaluate whether there were any differences in microleakage of class V composite restorations according to restoration site and cavity size. Total sixty-four restorations were made in molar teeth using Esthet-X. Small ($2\;{\times}\;2\;{\times}\;1.5\;mm$) and large ($4{\times}2{\times}1.5\;mm$) restorations were made at the buccal/lingual surface and the proximal surface each. After 1,000 times of thermocycling ($5^{\circ}\;-\;55^{\circ}C$), resin replica was made and the percentage of marginal gap to the whole periphery of the restoration was estimated from SEM evaluation. Thermocycled tooth was dye penetrated with $50\%$ silver nitrate solution. After imbedding in an auto-curing resin, it was serially ground with a thickness of 0.25 mm. Volumetric microleakage was estimated after reconstructing three dimensionally. Two-way ANOVA and independent T-test for dye volume, Mann-Whitney U test for the percentage of marginal gap, Spearman's rho test for the relationship between two techniques were used, The results were as follows : 1. The site and size of the restoration affected on the microleakage of restoration. Namely, much more leakage was seen in the proximal and the large restorations rather than the buccal/lingual and the small restorations. 2. Close relationship was found between two techniques (Correlation coefficient = 0.614/ P = 0.000). Within the limits of this study, it was noted that proximal and the large restorations leaked more than buccal/lingual and the small restorations. Therefore, it should be strictly recommended large exposure of margins should be avoided by reducing unnecessary tooth reduction.