7 research outputs found
A study of the influence of combined Glucosamine Sulfate and Chondroitin Sulfate systemic supplements on root resorption and tooth movement in rats
Orthodontic tooth movement is a periodontal ligament and alveolar bone phenomenon that involves microscopic and macroscopic changes in the periodontal ligament, alveolar bone and dental pulp. Root resorption is recognized as an unavoidable side effect of orthodontic tooth movement and numerous studies have been conducted in order to identify potential risk factors and possible methods to reduce or prevent this unwanted and often devastating side effect while maintaining or even improving the rate of tooth movement
The application of skeletal anchorage in the management of maxillary deficiency in growing children
Chapter one discusses oropharyngeal swallowing impairment due to head and neck cancer (HNC). Its complexity and severity arise from the dual physiological and structural changes to swallowing musculature. Expectations of recovery are difficult to predict due to the variety of treatment modalities, demographic and clinical characteristics, the risk of recurrence, implications of malnutrition, and the progressive nature of radiation fibrosis.
The second chapter reported on a systematic review and meta-analysis describing the relationship between radiation dose to critical swallowing structures. The third chapter explores this relationship in the definitive and post-operative setting. Chapter four evaluated swallowing impairment following transoral robotic surgery (TORS) for HNC using fibreoptic endocscopic evaluation of swallowing. A significant deterioration in swallow function, characterised by a heavy secretion load, pharyngeal residue, laryngeal penetration and aspiration was identified in most participants. The fourth chapter evaluated intensity modulated radiation therapy (IMRT) and TORS at 12 months post-treatment for oropharyngeal cancer. A statistically significant advantage for TORS was identified, when adjuvant radiotherapy which involved the primary site could be avoided. This finding correlates with one of the primary purposes for TORS, which was to achieve a deintensification of radiation, known to impair swallowing function as demonstrated in earlier chapters.
This thesis describes how technological advances in head and neck cancer treatment have changed the expectations for functional recovery. Both IMRT and TORS represent approaches which are intended to preserve critical swallowing structures in an effort to preserve swallowing function after treatment. While encouraging, results presented here demonstrate significant challenges which impact quality of life. Utilisation of instrumental assessment in this population remains imperative to characterise swallow physiology, particularly in light of high rates of silent aspiration and pharyngeal residue. This information will guide rehabilitation programs
Surgically assisted rapid maxillary expansion in lingual orthodontics – optimizing of coupling and timing
Abstract Background Surgically assisted rapid maxillary expansion (SARME) is primarily used in adult orthodontics. In many cases it is followed by further surgery to address further anteroposterior and/or vertical discrepancies. Treatment times in such cases are often long with adult patients usually requesting invisible appliances. Lingual appliances can provide the mechanical control required as well as fulfil the aesthetic demands in such cases. However lingual appliances are usually custom made and indirectly bonded. Due to tooth movement following surgery there is usually a long delay before impressions can be made for customized lingual appliances. This results in a long delay before alignement and leveling can be commenced post-surgery. Case presentations Three cases are presented here demonstrating the simultaneous placement of bone anchored expansion devices for surgically assisted rapid maxillary expansion with customized lingual appliances. Conclusions The combination of the two procedures allows the alignement and leveling to commence very soon after surgery significantly reducing treatment times. The design of the appliances and the clinical procedures are described and discussed
The short-term skeleto-dental effects of a new spring for the intrusion of maxillary posterior teeth in open bite patients
Background: The technology surrounding temporary skeletal anchorage devices has improved in leaps and bounds. However, no specific auxiliary exists for the intrusion of molars in conjunction with these devices and currently clinicians are forced to make do with available force delivery materials. A new intrusion auxiliary, the Sydney Intrusion Spring (SIS), was designed to facilitate intrusion without frequent need for reactivation or tissue irritation.\ud
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Methods: The subjects consisted of 16 adolescent patients (12 females and 4 males) with an average age of 13.1 years (range 12.2 to 14.3 years). All patients were in the permanent dentition with an anterior open bite of ≥2 mm. Four self-drilling miniscrews were placed into the posterior maxillary buccal alveolar bone. The intrusion appliance consisted of a bonded acrylic appliance and the SIS, activated to produce an initial intrusive force of 500 g. Cone beam computed tomograms were taken after miniscrew placement and at the end of active intrusion. Rendered lateral cephalograms were produced and measurements were taken and compared.\ud
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Results: All study objectives were achieved in 4.91 months (range 2.5 to 7.75 months). The mean molar intrusion was 2.9 ± 0.8 mm (P < .001), resulting in over bite increase of 3.0 ± 1.5 mm (P < .001). The intrusion led to a 2.6° ± 1.3° (P < .001) clockwise occlusal plane rotation and a 1.2° ± 1.3° (P < .01) counter-clockwise rotation of the mandible. Dental measurements showed a significant uprighting and elongation of the incisors. There was no significant extrusion of the lower molars.\ud
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Conclusion: The SIS is an effective appliance for the intrusion of maxillary posterior teeth, in conjunction with miniscrews
Early Class III treatment with Hybrid-Hyrax -Facemask in comparison to Hybrid-Hyrax-Mentoplate – skeletal and dental outcomes
Abstract Background Protraction of maxilla is usually the preferred and more commonly used treatment approach for skeletal Class III with a retrognathic maxilla. The aim of this study was the comparison of the skeletal and dental effects of two skeletally borne appliances for maxillary protraction: a) Hybrid-Hyrax in combination with facemask (FM), b) Hybrid-Hyrax in combination with Mentoplate (ME). Methods Thirty four Patients (17 facemask, 17 Mentoplate) were investigated by means of pre- and posttreatment cephalograms. The two groups matched with regard to treatment time, age gender and type of dentoskeletal deformity before treatment. Results Both groups showed a significant forward movement of A-point (FM GROUP: SNA + 2.23° ± 1.30°— p 0.000*; ME: 2.23° ± 1.43°— p 0.000*). B-Point showed a larger sagittal change in the FM Group (SNB 1.51° ± 1.1°— p 0.000*) compared to the ME group (SNB: − 0.30° ± 0.9°— p 0.070). The FM group showed a significant increase of the ML-NL + 1.86° ± 1.65° (p 0.000*) and NSL-ML + 1.17° ± 1.48 (p 0.006*). Upper Incisor inclination did not change significantly during treatment in both groups as well as the distance of the first upper Molar in relation to A-point. Conclusion Both treatments achieve comparable rates of maxillary protraction, without dentoalveolar side effects. Skeletal anchorage with symphysial plates in the mandible provides greater vertical control and might be the treatment of choice in high angle patients