The role of lateral cephalometric radiography and fluoroscopy in assessing mandibular advancement in sleep-related disorders

Mandibular advancement splints are successful in managing obstructive sleep apnoea (OSA) in selected subjects. For these to be effective, some improvement in the dimensions of the oropharyngeal airway must occur

The importance of a multidisciplinary approach to the assessment of patients with obstructive sleep apnoea

Obstructive sleep apnoea may present with a wide range of symptoms resulting in a variety of referral pathways. A multidisciplinary approach to examination and diagnosis helps to determine the most appropriate treatment plan for each individual. The subject is seen by each member of the team, appropriate investigations undertaken and a further meeting arranged at which all opinions are discussed. A reasoned treatment regime is produced, taking into consideration the patient's wishes and overall medical condition. This paper describes the team approach currently employed in the Department of Thoracic Medicine at The Prince Charles Hospital, Brisbane, Australia. The thoracic physician and ENT surgeon work in close collaboration with their dental colleagues: an orthodontist, prosthodontist and a maxillofacial surgeon. An outline of the examination and investigations made by each is described and the multidisciplinary approach is illustrated by a description of the management of five subjects with suspected obstructive sleep apnoea

Statistical methods for assessing agreement between double readings of clinical measurements

Statistical analysis of data is crucial in cephalometric investigations. There are certainly excellent examples of good statistical practice in the field, but some articles published worldwide have carried out inappropriate analyses. OBJECTIVE: The purpose of this study was to show that when the double records of each patient are traced on the same occasion, a control chart for differences between readings needs to be drawn, and limits of agreement and coefficients of repeatability must be calculated. MATERIAL AND METHODS: Data from a well-known paper in Orthodontics were used for showing common statistical practices in cephalometric investigations and for proposing a new technique of analysis. RESULTS: A scatter plot of the two radiograph readings and the two model readings with the respective regression lines are shown. Also, a control chart for the mean of the differences between radiograph readings was obtained and a coefficient of repeatability was calculated. CONCLUSIONS: A standard error assuming that mean differences are zero, which is referred to in Orthodontics and Facial Orthopedics as the Dahlberg error, can be calculated only for estimating precision if accuracy is already proven. When double readings are collected, limits of agreement and coefficients of repeatability must be calculated. A graph with differences of readings should be presented and outliers discussed