Repair of orthodontically induced root resorption by ultrasound in humans.

Root resorption is an adverse outcome of orthodontic tooth movement. In addition to the iatrogenic response and compromising the crown-root ratio, root resorption has led to increased malpractice litigation against orthodontists. A clinically acceptable method of treating root resorption has not been validated in the literature to date. Previous research has shown that low-intensity pulsed ultrasound (LIPUS) can enhance healing of various types of traumatized connective tissues and stimulate dental tissue formation. The purpose of this study was to evaluate the effect of LIPUS on the healing process of orthodontically induced tooth-root resorption in humans. Twelve orthodontic patients who were seeking orthodontic treatment that necessitated extracting the first premolars before mechanotherapy participated in this study. For each patient, buccally activated springs were used to tip the maxillary first premolars buccally, with an initial force level of 50 g; the springs were checked weekly to ensure continuous force levels. A short period of LIPUS was applied to 1 side of each patient's mouth, with the other side used as a control. After 4 weeks, the experimental premolars of all patients were extracted, and the premolars of 6 patients were studied by scanning electron microscopy (SEM); the premolars of the other 6 patients were studied histologically. The number and total area of resorption lacunae as examined by SEM were compared between the LIPUS-treated and the control premolars with a t test. The SEM study showed a statistically significant decrease in the areas of resorption and the number of resorption lacunae in the LIPUS-exposed premolars. Histologic examination showed healing of the resorbed root surface by hypercementosis. The results of this study provide a noninvasive method for reducing root resorption in humans.

Cuyahoga County Operation Stroke speed of emergency department evaluation and compliance with National Institutes of Neurological Disorders and Stroke time targets.

BACKGROUND AND PURPOSE: Although the National Institutes of Neurological Disorders and Stroke (NINDS) has established time targets for the evaluation of acute stroke patients, little is known about how often these targets are met in the community. To track compliance with NINDS guidelines, Cuyahoga County Operation Stroke implemented a countywide data collection process that provides comparative reporting of hospital performance. METHODS: Data on the emergency department evaluation of stroke patients have been retrospectively collected since January 2000 by hospitals participating in Cuyahoga County Operation Stroke. All hospitals used a 1-page form that includes NINDS time target information. RESULTS: Median time to emergency department arrival for the 1003 patients in this cohort was 115 minutes; 382 patients (38%) arrived in <3 hours; 506 (50%) arrived in <6 hours. After arrival, median time to physician contact was 12 minutes, time to CT was 65 minutes, and time to imaging results was 105 minutes. Earlier arrival intervals after symptom onset were independently associated with shorter evaluation times. All time targets were met in patients receiving intravenous tissue plasminogen activator. CONCLUSIONS: A countywide data collection system for acute stroke evaluation is feasible. In the Cleveland metropolitan area, time to physician contact is close to the recommended NINDS target. Time to CT and time to imaging results are substantially longer than recommended. However, there was wide variation between hospitals. The association between time to arrival, speed of evaluation, and administration of intravenous tissue plasminogen activator suggests that community physicians selectively accelerate the evaluation and management of potential thrombolysis candidates.

Growth modification of the rabbit mandible using therapeutic ultrasound: is it possible to enhance functional appliance results?

Previous studies have shown that functional appliances can enhance mandibular growth when applied during the active growth period. However, besides patient compliance problems with bulky appliances and prolonged treatment demands, there is contradictory evidence that functional appliances have a significant long-term effect. Is there a method to enhance the growth response and improve the long-term success of functional appliances? Previous studies have also found that therapeutic ultrasound (US) can stimulate cartilage and bone growth. The objective of this study was to evaluate the effect of therapeutic US on condylar and mandibular growth in the rabbit model. Eight growing New Zealand male rabbits were chosen for this study. They received therapeutic US on one side of the mandible for 20 minutes/day for four weeks. Anthropometrical and histological evaluations revealed that US enhances mandibular growth by condylar endochondreal bone growth and consequently mandibular ramus growth. The significant results of this study support conducting a long-term study to evaluate the ultimate stability of the results obtained. Also, they suggest an extended research with a larger sample size and investigating the molecular basis of this stimulatory effect, together with forward posturing splints for optimal macroscopic and microscopic responses.

Orthodontics and temporomandibular disorder: a meta-analysis.

As the importance of evidence-based health care has grown, meta-analysis has become more widely used in the medical and dental fields. In this meta-analysis, the relationship between traditional orthodontic treatment, including the specific type of appliance used and whether extractions were performed, and the prevalence of temporomandibular disorders (TMD) was investigated. After an exhaustive literature search of 960 articles, we found 31 that met the inclusion criteria (18 cross-sectional studies or surveys and 13 longitudinal studies). We divided and extracted data from the 31 articles according to study designs, symptoms, signs, or indexes. Due to severe heterogeneity, the results were summarized without further statistical analysis. The heterogeneous result might originate from lack of a universal diagnostic system and the variability of TMD. Because of heterogeneity, a definitive conclusion cannot be drawn. The data included in this comprehensive meta-analysis do not indicate that traditional orthodontic treatment increased the prevalence of TMD. It is apparent that a reliable and valid diagnostic classification system for TMD is needed for future research.

Ortodoncia: principios generales y técnicas

Diagnóstico y plan de tratamiento. Diagnóstico y plan de tratamiento en ortodoncia. Principios y reacciones biomecánicas. Fisiología, metabolismo y biomecánica del hueso en la práctica ortodóncica. Aplicación de la bioingeniería a la ortodoncia clínica. Aplicaciones de la informática en ortodoncia. Guía interceptiva de la oclusión con énfasis en el diagnóstico. Técnicas y tratamiento. Aparatos funcionales. Ortopedia combinada con aparato extraoral y activador. Tratamiento de la dentición mixta. Adhesión en ortodoncia. Aparato arco de canto de Tweed_merriefield: filosofía, diagnóstico y tratamiento. Mecánica de tratamiento con el aparato de arco recto. Interrelaciones ortodóntico-periodontales. Ortodoncia y cirugía ortognática: principios del tratamiento combinado. Contención y recidiva

Ortodoncia: principios generales y técnicas

Diagnóstico y plan de tratamiento. Diagnóstico y plan de tratamiento en ortodoncia. Principios y reacciones biomecánicas. Aplicación de la bioingeniería a la ortodoncia clínica. Implicaciones ortodóncicas en el diagnóstico, prevención y tratmiento de la disfunción de la ATM. Guía de oclusión: extracciones seriadas. Técnicas y tratamiento. Aparatos funcionales. Ortopedia combinada con activador y casquete. Adhesión en ortodoncia. El aparato arco de canto. El sistema Level Anchorage. Mecánica de tratamiento para el aparato de alambre recto. Técnica de Begg moderna: combinación de aparatos y técnicas de Begg y de alambre recto. Ortodoncia en adultos: diagnóstico y tratamiento. Contención

Ortodoncia. Principios Generales y Técnicas

Contiene : diagnóstico y plan de tratamiento. Técnicas y tratamiento

Ortodoncia. Principios Generales y Técnicas

Contiene : diagnóstico y plan de tratamiento. Técnicas y tratamiento