Influence of close resection margins on local recurrence and disease-specific survival in oral and oropharyngeal carcinoma.

There is a lack of consistency among published reports in the definition of what constitutes close resection margins (1-5mm) in the surgical treatment of oral and oropharyngeal squamous cell carcinoma (SCC). Our aim was to define what would constitute close resection margins in predicting local recurrence and disease-specific survival. The study comprised 192 previously untreated patients with oral and oropharyngeal SCC who were recruited at the Southern General Hospital, Glasgow, from 2001 to 2007 with a minimum follow-up of 2 years. Resection was the primary treatment and the surgical margins were recorded for all patients. Statistical analyses were aided by the Statistical Package for the Social Sciences, version 15.0, and MedCalc software. The status of the surgical margins was evaluated using a receiver operating characteristic (ROC) curve to define the cut-off point. Cox's proportional hazard model was used to establish predictive factors for local recurrence and disease-specific survival. Of 192 patients, 23 (12%) had involved margins (<1.0mm), 107 (56%) had close margins (1.0-2.0mm (16.1%); 2.1-3.0mm (12%); 3.1-4.0mm (10.4%); 4.1-5.0mm (17.2%), and 62 (32.3%) had clear margins (>5mm). No predictive cut-off point was found that related close surgical margins to local recurrence. However, there was a significant adverse association between surgical margins ≤1.6mm and disease-specific survival. In recommending postoperative adjuvant treatment for oral and oropharyngeal SCC, we suggest that surgical margins within 2mm should be considered as the cut-off. However, other clinical and pathological prognostic factors should also be taken into consideration when recommending further treatment.

Factors Contributing to the Spread of Odontogenic Infections: A prospective pilot study.

OBJECTIVES: Spreading odontogenic infections (SOI) are the commonest type of serious infections encountered in the orofacial region. A prospective multi-centre study was conducted in the West of Scotland to investigate the contributing role of social, systemic and microbial factors in the pathogenesis of SOI. METHODS: Twenty-five patients with severe odontogenic infections were recruited over a period of six months. At admission, clinical assessment included temperature rise, haematological and biochemical investigations. Demographic data, social and past medical histories were obtained. Microbiology samples were collected to identify causative microorganisms and the clinical management of each infection was recorded. RESULTS: Most infections were associated with teeth or roots. Eighty percent of the patients were tobacco smokers and 72% came from deprived areas. Five patients were intravenous drug users, four admitted chronic alcohol abuse, six had underlying systemic disorders and two were at high risk of malnutrition. A raised C-reactive protein at admission was a useful indicator of the severity of infection. Inappropriate prior antibiotic treatment in the absence of surgical drainage was common. Microbiology results showed a predominance of strict anaerobes, notably anaerobic streptococci, Prevotella and Fusobacterium species. CONCLUSION: SOIs remain surprisingly common and our present pilot study showed a particular association with social deprivation and tobacco smoking. Further elucidation of the role of malnutrition in SOI would be of interest. Molecular characterisation of the microflora associated with SOI may help to highlight whether bacterial factors play a role in converting a localised dentoalveolar abscess into a serious, spreading odontogenic infection.

Face bow and articulator for planning orthognathic surgery: 1 face bow.

Orthognathic surgery that involves movement of the maxilla relative to the skull is usually planned using casts mounted on an articulator. Accurate positioning of the maxilla relative to the skull is essential for reliable planning, but current methods of mounting casts on articulators are inaccurate and unreliable. We propose that the casts should be mounted using the relation between the horizontal plane and the resting head position to define the position of the skull. A photographic study of 10 subjects confirmed the reproducibility of the head position and its relation to the horizontal plane. A face bow incorporating a circular spirit level was used to transfer the relation between the horizontal and the maxillary dentition to a semiadjustable articulator. The angle between the horizontal and maxillary occlusal planes was measured from six lateral cephalograms and compared with those of casts mounted on a semiadjustable articulator using a face bow with either an orbital pointer or a spirit level. The face bow with a spirit level produced considerably more accurate results.

Face bow and articulator for planning orthognathic surgery: 2 articulator.

Patients who require orthognathic surgery may have asymmetry of the position of the temporomandibular joints relative to the maxilla, which is impossible to reproduce on the current semiadjustable articulators used for surgical planning. We describe a highly-adjustable spirit level orthognathic face bow that allows records to be made of patients with asymmetrical maxillae. The orthognathic articulator also allows the position of the condylar components of the articulator to be adjusted in three dimensions. The use of the new face bow and articulator made it possible to mount the dental casts of asymmetrical faces to reproduce their clinical appearance. The devices were evaluated by comparing the measurements of anatomical variables obtained from cephalometric radiographs with equivalent values obtained from the orthognathic articulator and casts mounted on the articulator. Although the measurements showed significant intersubject variability, the angle between the horizontal and maxillary occlusal plane, occlusal cant angle, and intercondylar widths, were not significantly different.

One miniplate versus two in the management of mandibular angle fractures: a prospective randomised study.

We compared the use of one miniplate (n=36) with that of two miniplates (n=26) for the treatment of the mandibular angle in a randomised trial. There were no significant differences between the groups in total morbidity (22/36 compared with 14/26) or for individual complications. We conclude that two miniplates seem to confer no extra benefit to patients, but a much larger trial would be required to show this conclusively.

Ameloblastoma: a surgeon's dilemma.

PURPOSE: To investigate whether there were any significant differences in the mode of presentation, treatment, and outcome of patients presenting with a primary diagnosis of ameloblastoma in Glasgow, Scotland and San Francisco, CA. MATERIALS AND METHODS: All cases of ameloblastoma seen in both institutions between January 1, 1980 and December 31, 1999 were included in this study. Mode of presentation, radiographic appearance, histologic appearance, treatment, and follow-up were recorded. RESULTS: There were no significant differences in the clinical features on presentation (swelling, followed by pain, and altered sensation), the radiographic appearance (unilocular approximately 30% and multilocular 70%), or management with either local treatment (enucleation and/or curettage in just over 50% of cases) or radical treatment (a form of resection in under 50%) in the 50 cases included in this study. Primary care by conservative treatment led to a recurrence in approximately 80% of cases and this included cases of unicystic ameloblastoma. CONCLUSION: The mode of presentation, diagnosis, and management of the ameloblastoma was remarkably similar in Glasgow and San Francisco. The recurrence rate following local enucleation and curettage was unacceptably high, and this included the cases of unicystic ameloblastoma, which should be treated more aggressively than has been recommended in the past.