Objective: Assess the changes in oral health-related quality of life (OHRQoL) of adolescents and their parents after overjet reduction. Materials and Methods: 53 patients between the ages of 11-18 years with increased dental overjet (≥ 6mm) and their parents were selected, of which 28 were pre- and 25 were post-treatment with dental overjet reduced to within normal limits. The data collection instrument was the Child Oral Health Quality of Life (COHQoL) Questionnaire. Results: Adolescents and their parents reported poorer quality of life before orthodontic treatment than after. The improvement in oral health-related quality of life was statistically significant for all health domains except for the social well-being domain. Parental reports on (OHRQoL) were in agreement with their children’s. No statistically significant differences were evident in (OHRQoL) between pre- and post-treatment groups. Conclusions: Adolescents with increased dental overjet ≥6mm experienced substantial psycho-social impacts. Adolescents with increased overjet can accurately recall the initial negative effects of the original malocclusion on their lives, even after a time lapse of five years. Orthodontic treatment significantly improves the perceived quality of life of orthodontic patients and their parents

Increasing the rate of orthodontic tooth movement (OTM) can reduce risks such as periodontal disease and caries. This study investigated whether light emitting diode (LED) phototherapy could accelerate the rate of OTM. Orthodontic patients with bilaterally symmetric extraction of premolars were recruited. During space closure, LED phototherapy was applied to one side of the dental arch for a specified time and the contralateral side acted as the control. Space closure was measured immediately prior to, during and later in space closure. All 11 patients were compliant with LED application. The results revealed no significant changes in the rate of OTM with LED phototherapy over 3 months of extraction space closure. The findings were contrary to previous findings with laser phototherapy and could be related to the dosage or method of LED phototherapy delivery. Further investigations are needed to determine whether LED phototherapy application can influence the rate of OTM.

Nitric oxide (NO) plays a role in regulating the rate of orthodontic tooth movement (OTM) in rat models; however, in humans this role remains less clear. In this study, samples of gingival crevicular fluid (GCF) were collected from each maxillary central incisor and first and second molar immediately before (T0), 1 hour after (T1), and 3-4 days after (T2) application of light orthodontic forces in thirteen male participants (ages 11-18 years) undergoing orthodontic therapy. NO levels were measured in each GCF sample, and significantly higher NO levels (p<0.05) were found at T1 at the buccal surfaces of the central incisors when compared to the posterior teeth. The results indicate a possible role for NO in OTM at the pressure sites of incisors at early time points. Further studies are required to determine whether NO levels in the PDL of human teeth are affected by the magnitude of an applied force.

The Finite Element Method of stress analysis is employed in axisymmetric, two and three-dimensional forms, to investigate the mechanical behaviour of dental structures under simulated oral loading conditions. Stress distributions which are examined, include those occuring in the crowns of normal teeth due to masticatory loading and in restored teeth as a consequence of the restoration's setting and thermal expansions. The force distributions occuring on roots of individual teeth and on teeth used as abutments for various bridge constructions are also investigated for both axial and non-axial loading and various alveolar bone support conditions. The instantaneous centres of rotation of teeth when subjected to orthodontic loading are also determined. The Finite Element Method is employed to examine various published hypotheses which attempt to correlate the mechanical behaviour of bone structures with that tissue's biological response characteristics. The cases examined include the remodelling of the alveolar process subsequent to orthodontic treatment and the remodelling or so-called straightening of the malaligned long bone. Utilising published experimental data, the Finite Element Method is also employed in a reverse mode to enable some hitherto unknown mechanical properties of the periodontal membrane and cortical bone tissues to be determined. Indeed, due to the flexibility of the method, it was possible to represent these tissues as orthotropic materials. The work is presented in two volumes. While the first volume contains all the results of the analyses, the second contains an outline of the relevant finite element theory. Nevertheless, where the theory has been extended, in particular in the area of non-isotropic material analysis, it is developed in greater depth. The second volume also contains both a thorough description and a listing of all the computer programs developed.

Objective: Assess the changes in oral health-related quality of life (OHRQoL) of adolescents and their parents after overjet reduction. Materials and Methods: 53 patients between the ages of 11-18 years with increased dental overjet (≥ 6mm) and their parents were selected, of which 28 were pre- and 25 were post-treatment with dental overjet reduced to within normal limits. The data collection instrument was the Child Oral Health Quality of Life (COHQoL) Questionnaire. Results: Adolescents and their parents reported poorer quality of life before orthodontic treatment than after. The improvement in oral health-related quality of life was statistically significant for all health domains except for the social well-being domain. Parental reports on (OHRQoL) were in agreement with their children’s. No statistically significant differences were evident in (OHRQoL) between pre- and post-treatment groups. Conclusions: Adolescents with increased dental overjet ≥6mm experienced substantial psycho-social impacts. Adolescents with increased overjet can accurately recall the initial negative effects of the original malocclusion on their lives, even after a time lapse of five years. Orthodontic treatment significantly improves the perceived quality of life of orthodontic patients and their parents

Biological responses to orthodontic forces involve various cell types, these include fibroblasts, endothelial cells, blood vessels and sensory nerves in the periodontal ligament as well as osteoblasts, osteoclasts and cementoblasts in roots and bone surfaces. Neurotrophins are believed to interact with these cells to initiate the process of bone resorption particularly during orthodontic tooth movement. Neuropeptides released from sensory neurons have been shown to modulate the tissue inflammatory responses. In addition, neurotrophins, including nerve growth factor (NGF), play an important role in neural cell differentiation and survival. The exact localization and function of neurotrophins and neurotrophic receptors in the dento-alveolar complex remains unclear. Moreover, the identity and distribution of structures expressing neurotrophins and neurotrophic receptors has yet to be fully determined. It is reasonable to propose that periodontal ligament and alveolar bone remodelling may be influenced by NGF. In addition, anti-NGF may block neurochemical changes and, hence, inhibit orthodontic tooth movement. The aims of this research were to investigate the cells responsible for NGF secretion within the periodontal ligament (PDL), pulp and bone, and the effect that anti-NGF might have on orthodontic tooth movement. 28, 8 week-old, male Sprague-Dawley rats were randomly divided into control and experimental groups. Fourteen experimental animals had anti-NGF injected paradentally. Animals were sacrificed at 7 and 14 days. Sections from an earlier study were examined and stained using TRAP for osteoclast identification and analysed histomorphometrically to enable comparisons between control and experimental groups. The findings of this investigation indicated that injections of anti-NGF did not significantly affect the rate of tooth movement with the use of different tooth movement measurement methods. TRAP staining proved to be a useful and reliable marker of osteoclasts. TRAP-positive osteoclastic cells were detected in both anti-NGF and control groups. However, the TRAP-positive cells were not stained intensely with NGF immunolabelling. On the other hand, cells that were stained intensely with NGF, were TRAP-negative. The results suggested that both sympathetic and nociceptive nerves might function in counter balance to modulate bone resorption, and osteoclasts might not be directly responsible for NGF secretion within the PDL and bone. Further studies to determine the effect of NGF on tooth movement are warranted to more clearly identify the NGF expressing cells within the rat dento-alveolar complex and possible role played by NGF in orthodontic tooth movement. / http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1297498 / Thesis (D.Clin.Dent.)-- School of Dentistry, 2007

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2005. / Härtill 5 uppsatser.

Thesis (M.S.)--University of Alabama at Birmingham, 2008. / Title from first page of PDF file (viewed June 2, 2008). Includes bibliographical references.

Thesis (M.S.)--University of Alabama at Birmingham, 2008. / Title from first page of PDF file (viewed May 30, 2008). Includes bibliographical references.

Thesis (M.S.)--University of Alabama at Birmingham, 2008. / Title from first page of PDF file (viewed May 30, 2008). Includes bibliographical references.