Are more nickel ions accumulated in the hair of fixed orthodontic patients.

Background and Objectives : All elements existing in orthodontic alloys can be released to the oral cavity as corrosion products; therefore, they can accumulate in body tissues after systemic absorption. Among body tissues that can be evaluated for systemic absorption of nickel, in this study we used hair strands, because if nickel is absorbed systematically, it would accumulate in these strands over time. Furthermore, hair sampling is a non-invasive method, so the main aim of this study was the evaluation of nickel ions release into the hair strands of fixed orthodontic patients compared with the control group in a 4-month duration. Materials and Methods: In this clinical trial, the test group included 24 female patients between 12-20 years of age that were going to begin fixed orthodontic treatment. The control group consisted of their sisters in the same age range, who volunteered to participate in this study. Initial hair samples were taken from both groups at the beginning the study and immediately before setting up the fixed appliances in test group. The samples were taken from three different scalp sites including; frontal, vertex, and occipital areas. After 16 weeks, hair samples were taken from approximately the same scalp areas in both the groups. The samples were analyzed by atomic absorption spectrophotometer and data analyzed by Mann-Whitney test. Results: This study showed that there were significant differences in nickel levels before and after study for case (P = 0.004) and control groups (P = 0.012). The mean nickel concentration after four months was 0.382 ± 0.36 μg/g for controls and 0.673 ± 0.38 μg/g for the case group, which was significantly different (P = 0.002). Conclusion: The hair nickel concentrations significantly increased after insertion of fixed orthodontic appliances as compared with the control group.

Evaluation of the Divine Proportion in the facial profile of young females.

BACKGROUND: Beauty is the phenomenon of experiencing pleasure, through the perception of balance. According to some authors, attractive faces have ideal proportions that are related to the Divine Proportion (1.618:1). AIM: The purpose of this study was to evaluate the Divine Proportion in the human profile and investigate the effects of this ratio on the perception of the beauty of the profile. STUDY AND DESIGN: We conducted a cross-sectional study to determine the mentioned aims. MATERIALS AND METHODS: In this cross-sectional study, fifty females in the age range of 20-25 years, with acceptable profiles were selected. Standardized profile silhouettes were each given a score by 20 judges (consisting of 10 men and 10 women) using the visual analog scale. Five landmarks were determined and five ratios were measured on the silhouettes by using the adobe photoshop program. STATISTICAL ANALYSIS: The Student's t test was used to compare profile proportions of the subjects. RESULTS: Statistical analysis showed none of the proportions had the mean of 1.618, but in subjects having higher esthetic scores, trichion (Te)-soft tissue menton (Me):Tr-subnasale (Sn) and Tr-Me:soft tissue nasion (N)-Me, with the mean of 1.58 were closer to Divine Proportion. CONCLUSIONS: The results suggested the perception of beauty is influenced by the Divine Proportions and Tr-Me:Tr-Sn and Tr-Me:N-Me are the most influential ratios in the perception of the beauty of profile; however, if the Divine Proportion is to be used in treatment planning, it should be used along with other factors.

The effects of upper lip height on smile esthetics perception in normal occlusion and nonextraction, orthodontically treated females.

BACKGROUND: The esthetic of smile is influenced by such features as the amount of incisor show and gingival display. AIMS: The purposes of this study were to compare smile esthetics among normal occlusion and non extraction patients, assess upper lip height in two groups and discuss how this feature relate to smile esthetics. SETTINGS AND DESIGN: We therefore conducted a case control study to determine the mentioned aims. MATERIALS AND METHODS: Thirty females with non extraction orthodontically treated occlusions and thirty three with normal occlusions were selected. Standardized black and white photographs of their posed smiles were evaluated by a panel of 5 men and 5 women of varied vocations by use of visual analogue scale. Then upper lip height of the two groups were measured from photographs. Statistical Analysis: Smile esthetics and differences among the two groups were subjected to ANOVA and Mann-whitney test was used to compare upper lip height in them. Results: This study showed that upper lip height did not differ among the 2 groups ( P = 0.98). Also there were no significant differences in the distribution of fair,good and very good smiles among the two groups. Conclusions: This study demonstrates that the non extraction orthodontic treatment does not influence smile esthetics.