British journal of orthodontics最新文献

This paper aims to examine and highlight the difference between sources of stress and burn-out. The first part of the paper examines stress and the second part looks at the concept of burn-out with reference to how orthodontists compare with other dental professionals.

The cases presented and treated at successive examinations by the candidates for the Membership Examination in Orthodontics in 1995 and 1996 at The Royal College of Surgeons of England, were of a very high standard and demonstrated a wide range of treatment modalities. All cases had fixed appliances, predominantly with pre-adjusted Edgewise appliances. IOTN confirmed that most cases were in great need of treatment, with PAR scores showing them to be treated to a high standard.

The objective of this study was to evaluate the use of the Laser Döppler Flowmeter (LDF) in the measurement of pulpal blood flow following orthognathic surgery and to conduct an initial study of the effects of a Le Fort I osteotomy on the pulpal blood flow of the maxillary central incisors. The design consisted of a preliminary prospective controlled consecutive clinical trial undertaken at the Orthodontic Clinic, University Dental Hospital NHS Trust, Wales, 1994. The study group consisted of 15 consecutive patients who were to receive a standard advancement Le Fort I osteotomy. Seven patients who were to undergo a mandibular advancement only acted as a control. A further 20 separate patients participated in a study for the assessment of measurement error. The blood flow in relative perfusion unit v. time, was measured using a Laser Döppler Flowmeter. Measurement error for flowmeter recordings with hand-held application and custom-made splint support showed no consistent difference or significant random variation between the two methods for holding the probe against the teeth (pooled S.D. of reproducibility 1/1 = 1.91/1.39 for custom splint location as opposed to 0.96/1.07 for hand-held/fixed bracket location). For the surgical patients under investigation no significant differences for maxillary pulpal blood flow were found in the control group (mandibular osteotomy) over time. However, in the maxillary osteotomy patients there was a tendency for an initial rise in the maxillary perfusion post-surgery as measured at the central incisor pulps, followed by an overall reduction at 6 months. As an example, the mean value for the upper right central showed a significant increase in blood flow during the immediate post-operative period (P < 0.05), but at 6 months after surgery demonstrated a statistically significant overall reduction in comparison with the presurgical reading (P < 0.001). The laser Döppler flowmeter is not an easy instrument to use in the clinical assessment of pulpal blood flow. However, it would appear from these longitudinal series of readings, taken over a 6-month period on 15 patients, that the maxillary perfusion recorded at the central incisor pulps may be permanently affected in many Le Fort I osteotomy patients. For patients that already have a prejudiced blood supply this could lead to devitalization and discoloration of incisors. It is not known if this affect on the perfusion of the pulp continues beyond 6 months post-surgery.

Undergraduate orthodontic education in Australian university dental schools reflects a strong British influence. The Australian Dental Council is now responsible for undergraduate course accreditation and the development of a more distinctly Australian model might be expected, although not in isolation from the traditional British and American influences. Postgraduate specialty training has been more directly influenced by the North American dental schools, and specialist registers in the states and territories reflect that influence. The Australian Dental Council will commence accreditation of postgraduate specialty courses in 1999.

The object of the study was to examine changes in dento-facial dimensions and relationships during the third decade of life, and consisted of a prospective cephalometric study. The data used consisted of 90 degree left lateral cephalometric radiographs of 21 males and 26 females at ages 18 years (T1) and 21 years (T2), and for 15 of the males and 22 of the females at 28 years (T3). Various dimensions representative of dento-facial morphology were measured and the changes in dimensions over time were calculated and tested for significance with the one sample t-test. In general, skeletal and dental relationships remained relatively stable. Face height and jaw length dimensions increased by small amounts.

Magnets have been used in dentistry for many years. They can be made to push or pull teeth. The force they deliver can be directed, and they can exert their force through mucosa and bone, as well as within the mouth. In orthodontics they are used for intrusion of teeth, tooth movement along archwires, expansion, retention, in functional appliances, and in the treatment of impacted teeth. New 'high energy' magnets are capable of producing very high forces relative to their size. Although magnets are potentially very useful there are a number of problems that severely affect their performance; the force produced between any two magnets falls dramatically with distance, significant irreversible loss in force is seen if the magnets are heated and a dramatic reduction in force is seen if the magnets are not ideally aligned to one another. In addition, magnets corrode badly in the mouth and a robust coating is required to protect them. This paper outlines the background to high energy magnets used in orthodontics, discusses the relevant physical and biological properties of them, and reviews their applications.