Impact of recycling on the mechanical properties of nickel-titanium alloy wires and the efficacy of their reuse after cold sterilization.

OBJECTIVE: This study aimed to assess the feasibility of reusing nickel-titanium (NiTi) alloy wires after 6 weeks of intraoral use by evaluating the changes in the load-deflection properties and surface characterization of these alloy wires after cold sterilization by immersion in 2% of acidic glutaraldehyde for 10 h. MATERIAL AND METHODS: Twenty wires each in three groups of G1-as-received wires (ARW), G2-unsterilized used wires, and G3-sterilized used wires (SUW) were tested by the three-point bending test and scanning electron microscopy (SEM). The data were subjected to statistics, one-way analysis of variance, and Bonferroni posthoc test for comparison. RESULTS: Recycling of NiTi wires produced statistically insignificant changes in both the loading and unloading properties of the wires. The forces needed to twist the used wires, that is, G2-(UUW) and G3-(SUW) were lower than G1-(ARW), suggesting lowering of the stiffness of the wires. Superelasticity is well-maintained by G2-(UUW) and G3-(SUW) although there is an insignificant lowering of the forces exerted by them during loading and unloading. SEM demonstrated no increase in the pitting of surfaces in both G2-(UUW) and G3-(SUW); multiple areas were seen to be more smoothened over G2-(UUW) and G3-(SUW) NiTi wires surfaces. CONCLUSION: The findings of this study support the reuse of NiTi wires after 6 weeks of use in oral conditions followed by cold sterilization by immersion in 2% acidic glutaraldehyde for 10 h.

Correlation of soft palate morphology to growth pattern: A retrospective cephalometric study.

AIM: The aim of the present study was to evaluate the radiographic length of velum (LV), width of velum (WV), velum angle (AV), depth of pharynx (PD), Need's ratio (NR), inclination angle (AI) in different morphological types of soft palate according to growth patterns in skeletal class I individuals. METHODOLOGY: 80 pretreatment lateral cephalograms of patients with skeletal class I malocclusion (ANB 2--4°) were divided on basis of six types of soft palate and further into three subgroups according to growth pattern and evaluation of LV, WV, angle with the palatal plane, and NR was done. Kruskal--Wallis test was used for the comparison between the groups. RESULTS: Statistically significant difference was verified among all groups for measurement of NR. The highest NR was seen in Crook type of soft palate (mean 0.9). Similarly, the vertical growth pattern in all the six types of soft palate exhibited a higher NR than the average and horizontal growth pattern group; the highest being exhibited by vertical group in type VI (crook shaped). Velopharyngeal insufficiency is directly related to NR. CONCLUSION: Vertical growth pattern has the highest susceptibility to velopharyngeal insuffiency and speech and sleep apnea disorders.

A survey on orthodontic services provided by general dental practitioners.

The aim of this survey-based study was to recognize professional determinants that account for variations in the level of orthodontic services provided and which distinguish providers and nonproviders of orthodontic services. Multiple regression analysis revealed that four practitioner characteristics explained 43% of the variance in the number of orthodontic patients treated. Dentists who treated more orthodontic patients (1) treated more general practice patients, (2) frequently used multiple sources to keep up to date in orthodontics, (3) perceived their patient base to contain more children, and (4) were likely to have attended an orthodontic course. The null hypothesis that selected characteristics of dentists providing orthodontic services were no different from those of dentists not providing orthodontic services was rejected. The provision of orthodontic services was associated with a higher level of continuing orthodontic education and treating more general practice patients, especially children.

Elevated levels of Interleukin (IL)-1ß, IL-6, tumor necrosis factor-α, epidermal growth factor, and ß2-microglobulin levels in gingival crevicular fluid during human Orthodontic tooth movement (OTM).

AIM: The aim of this study was to identify and quantify the various cytokines in human gingival crevicular fluid (GCF), and to investigate the changes in their levels during orthodontic tooth movement (OTM). MATERIALS AND METHODS: A statistically significant no. of subjects (n = 10 and mean age = 15.6 years) were included in the study. A maxillary cuspid of each subject having one treatment for distal orthodontic tooth movement served as the experimental tooth, whereas the contralateral cuspids were used as controls. Gingival crevicular fluid (GCF) around the experimental and the two control teeth was collected from each subject immediately before activation, and at 1, 24, and 168 hours after the initiation of tooth movement. RESULT: ELISAs were used to determine cytokine levels. The concentrations of interleukin (IL)-1lß, IL-6, tumor necrosis factor-α, epidermal growth factor, and ß2-microglobulin were significantly higher in the experimental group than in the controls at 24 hr after the experiment was initiated. All the cytokines remained at baseline levels throughout the experiment for the control groups. CONCLUSION: Since all cytokines in GCF play an important role in the bone remodelling processes in vivo, the present results indicate that the changes in cytokines in GCF are associated with OTM.

Psychological impact of orthodontic treatment on quality of life - A longitudinal study.

OBJECTIVE: (1) To assess the psychosocial, functional and aesthetic changes in young adults pre- and post-orthodontic treatment. (2) To assess the changes in quality of life in individuals having malocclusion before and after orthodontic appliance therapy. (3) To evaluate the effect of severity of malocclusion pre- and post-orthodontic treatment on quality of life among males and females. MATERIALS AND METHODS: This longitudinal study included a convenience sample of 18.1 to 25.3-year-old young adults (n=400). The self-perception of dental aesthetics pre- and post-treatment related to gender variations and severity of malocclusion (Angle's class I, II, III) were also assessed using the Psychosocial Impact of Dental Aesthetics Questionnaire with additions (PIDAQ) according to the needs of Indian ethnic group. Cronbach alpha of each domain at baseline score and Wilcoxon signed ranked test was carried out. RESULTS: Statistically positive psychosocial impacts were observed after orthodontic treatment for the six PIDAQ domains (P<0.001 for all six domains). There was a similar influence of gender and severity on the improvement of scores over the period in all the domains though males showed the least psychological impact on matrimonial concerns both pre- and post-treatment. The severity of malocclusion showed a difference only in functional concerns. There was less improvement in class III malocclusion group as compared to class I and class II groups. DISCUSSION: Orthodontic treatment has a positive psychological impact, as there was a significant improvement in self-esteem and social interaction of the individuals. Significant changes occurred in functional and aesthetic domain measures of quality of life in orthodontically treated cases. The severity of malocclusion has a negative impact on the quality of life and a significant improvement in the quality of life was observed before and after orthodontic treatment with no gender difference.

Comparison of 3D plate and locking plate in treatment of mandibular fracture-a clinical study.

INTRODUCTION: This study was performed to evaluate the efficacy and post-operative complication of 3-dimensional (3D) titanium miniplate and locking plate in mandibular fractures (parasymphysis, symphysis, body, and angle). MATERIALS AND METHODS: Forty patients, with non-comminuted mandibular fractures treated with open reduction and internal fixation using 3D titanium miniplate system or locking plate system through an intra-oral approach, were included in this study. All patients were systematically monitored up to 2 months post-operatively. Parameters recorded were infection, occlusal discrepancies, hardware failure, wound dehiscence, sensory disturbance of the inferior alveolar nerve, and stability of fractured segments. RESULTS: Forty patients with mandibular fracture were divided into two groups randomly without any bias. The fractures of all 40 patients were found to be adequately fixed when checked intra-operatively after fixation. One patient (2.5%) of the 3D plate group developed an infection on the first and second post-operative visit and was treated by antibiotic coverage. One patient in the locking plate group (2.5%) reported wound dehiscence after the first week follow-up. CONCLUSION: Both 3D titanium miniplates and locking plate are effective in the treatment of mandibular fractures, and overall complication rates are lesser. However, the 3D plating system uses less hardware in cases of parasymphysis and symphysis fractures and more hardware in cases of body and angle fractures.

Smart sliding hook as a ready to use auxillary in orthodontist׳s inventory.

Orthodontic treatment often requires extraction or distalization for gaining space. With both treatment modalities, emphasis has always been given to the simplicity and effectiveness of the treatment, time required for each visit, cost and minimum requirement of the inventory. To accomplish this, various appliances and auxiliaries have been designed in the past of which sliding jigs are commonly used. They pose various clinical problems of which time to fabricate them for each patient is one as they cannot be stored in a prefabricated form. Hence a versatile smart sliding hook is introduced as a ready to use auxillary which is biomechanically efficient, convenient to patients, economical, time saving, easy to fabricate and can be prefabricated making it clinically very helpful for orthodontists in day to day practice.