Comparative evaluation and influence of various staining agents on color stability and fluorescence of different esthetic orthodontic wires: An in vitro study.

OBJECTIVES: This study aimed to compare and evaluate the effect of three staining solutions on the color stability of three different brands of esthetic archwires using a spectrophotometer and also to compare the fluorescence of esthetic archwires with extracted human teeth. MATERIALS AND METHODS: A total of 84 nickel-titanium (NiTi)-coated esthetic archwires with the same cross section and size (0.016 × 0.022″) were included. All samples were divided into four groups of 21 each, that is, group 1: artificial saliva (AS), group 2: coffee (C) solution, group 3: turmeric (T) solution, and group 4: chlorhexidine (CH) mouth rinse; each group was subdivided into three subgroups of seven each (Opal Classic (OC), Libral Rabbit Force (LRF), and Ortho Organizers (OO)). The baseline value (T0) was measured before immersion in the staining solution and then immersed in the staining solution for 21 days. The color measurements were recorded at different time intervals on the 7th, 14th, and 21st days using a spectrophotometer. The fluorescence of archwires is tested in a dark atmosphere using a fluorescent black lamp. The data obtained were analyzed using descriptive statistics, analysis of variance (ANOVA), and post hoc Bonferroni test. RESULTS: A significant amount of color change in all three brands of archwires from day 0 to day 21 (p < 0.005) was observed, except for OC in the CH mouth rinse group (p = 0.230). The fluorescence of OO matches with the natural teeth. CONCLUSION: LRF showed the highest overall color change followed by OO and OC. Turmeric is the most chromogenic agent, followed by Coffee and CH mouth rinse.

Soft tissue esthetic norms for mahabubnagar population of southern India.

AIMS: The Aim of the study was to establish Soft Tissue Cephalometric Norms for skeletal and dental relationships amongst the Mahabubnagar adult population. MATERIALS AND METHODS: Sixty subjects (30 Males & 30 Females) subjects from different part of Mahabubnagar in the age group 18-25 Years (Mean age 21.3 Years) were selected at random for the study and lateral cephalograms were taken. All the cephalograms were traced by two operators using conventional hand tracing. The parameters used in the study were taken from Arnett and Bergman soft tissue cephalometric analysis (STCA). Overall 46 measurements including 40 linear, 6 angular parameters were used. Mean and standard deviation values were calculated. The difference between males and females were evaluated using student t-test. RESULTS: The values obtained from the study showed significant difference in most of the parameters from that of Arnett et al., norms and between males and females within Mahabubnagar population. CONCLUSION: Males had thicker soft tissue structures, acute nasolabial angle, increased facial lengths and heights, increased midface deficiency, recessive lower face, more convex profile and less upright mandibular incisors than females within Mahabubnagar population.

Torque Loss in En-Masse Retraction of Maxillary Anterior Teeth Using Miniimplants with Force Vectors at Different Levels: 3D FEM Study.

OBJECTIVE: This FEM study was conducted to quantify the amount of torque loss in maxillary anterior teeth by applying force vectors from different levels to the anterior retraction hook at various heights and comparing with that of molar anchorage system. MATERIALS AND METHODS: Five 3D FEM models were constructed with force vectors at different levels: HOT-High Orthodontic Traction (13.5mm from archwire) to ARH1- Anterior Retraction Hook (5mm), HOT to ARH2 (8mm), LOT- Low Orthodontic Traction (8 mm) to ARH1, LOT to ARH2 and from conventional molar hook to ARH1. Mini-implants were placed buccally between the roots of second premolar and first molar. Torque loss was calculated by measuring the displacement of the teeth at crown tip and root apex in two planes i.e. sagittal and vertical using Y and Z axis respectively in all the five models. The results were statistically analyzed by using Kruskal Wallis ANOVA and Mann-Whitney U-test. RESULTS: HOT to ARH1 showed that the anterior teeth moved bodily (p =0.5127), followed by molar hook - ARH1(p=0.0495*) which showed mild uncontrolled tipping. Whereas the HOT- ARH2, LOT - ARH1,and LOT - ARH2 models exhibited uncontrolled tipping with maximum torque loss in LOT - ARH1 (p=0.0001*). CONCLUSION: It can be concluded that bodily movement with very minimal torque loss was observed in HOT-ARH1 model whereas the maximum torque loss was recorded in LOT-ARH2 model. Conventional molar anchorage group showed uncontrolled tipping with some amount of extrusion and anchor loss of posteriors.

Modification of uprighting spring for derotation of second molars.

One of the most efficient ways for the correction of rotated upper molars is derotation with a transpalatal arch, but this appliance is usually favourable when the need for correction is same on both sides of the dental arch. Derotation of unilateral upper second molar is a difficult task, especially when there is no accessible tooth/ any attachment is available distal to it for the application of couple forces. We have designed a modification of uprighting spring which is far more convenient than using the conventional method of TPA for derotation of unilateral upper second molar.