Accuracy of the Third Molar Eruption Predictor in predicting eruption

OBJECTIVE: To evaluate the possibility of applying the Third Molar Eruption Predictor to all panoramic radiographs. STUDY DESIGN: Panoramic radiographs were retrospectively analyzed from a 4-year follow-up study of third molars carried out at the University of Copenhagen, Denmark. The radiographs, taken at a mean age of 20.6 years, included 45 unerupted or partially erupted mandibular third molars in 28 subjects. Because the device was calibrated both with simple proportions and by use of the methods of Bayes' Decision Theory, the separation point of the device was therefore adjusted at 12 mm from the distal surface of the second molar. RESULTS: The predictions of future eruption or impaction made with the calibrated device and the actual clinical outcome 4 years later were in conformity for 80% of the mandibular third molars. CONCLUSION: The Third Molar Eruption Predictor may be applied to all panoramic radiographs, but it seems to require calibration before use.     

Comparison of four methods of assessing root surface debridement

BACKGROUND: While there is great interest in measuring the efficacy of root surface debridement, there is little consensus on how this might be best achieved. The aim of this study was therefore to compare four different methods of assessing root surface debridement in their ability to discriminate between ultrasonically instrumented root surfaces and non-instrumented control surfaces. METHODS: Single-session subgingival root debridement was performed by an experienced operator on 30 teeth prior to their extraction. Following extraction, efficacy of root surface debridement was measured by percentage of remaining calculus, instrument efficiency, modified instrument efficiency, and percentage apical plaque border. In addition, the effect of probing depth landmark (apical plaque border versus connective tissue attachment) on outcomes was assessed. RESULTS: The results indicated that percentage apical plaque border demonstrated highly statistically significant differences between instrumented and control surfaces (P= 0.02). No other assessment method was able to discriminate between instrumented and non-instrumented surfaces, and this may be a function of the low amount of root surface calculus in the experimental sample. In addition, choice of probing depth landmark had a notable effect on the outcomes for instrument efficiency and modified instrument efficiency. Ninety-five percent limits of agreement of interexaminer reproducibility were found to be much higher than intra-examiner measurement for all four methods of assessment. CONCLUSIONS: Percentage apical plaque border appeared to be potentially more useful than other methods for assessing the efficacy of debridement of periodontally involved root surfaces, particularly for measuring instrument penetrability.     

Referral patterns and the referral system for oral surgery care. Part 2: The referral system and telemedicine

OBJECTIVE: To investigate GDP opinions of the current referral system and to investigate the need and demand for telemedicine in oral surgery referrals. DESIGN: Postal questionnaire. SETTING: 400 GDPs in Greater Manchester. RESULTS: 84% participation rate. 48% were not satisfied overall with the service of their current specialist oral surgery referral site. The principal reason was the length of the waiting time for consultation and treatment. Distance for patients to travel to the specialist unit was also of concern, even though most patients (89%) travelled short distances (return journey of twelve miles or less). 23% of respondents wished to improve their ability to communicate with the oral surgeon and 70% wanted involvement in the patient consultation. Both of these requirements were more likely in younger practitioners. CONCLUSION: There is a need and demand for change in the referral system for oral surgery specialist care. Telemedicine could conceivably be one way to improve access to specialist oral surgery care.     

Odontogenic ghost cell carcinoma: a case report with reference to the relation between apoptosis and ghost cells

The neoplastic variant of calcifying odontogenic cyst has various designations, and its malignant counterpart has been reported as aggressive epithelial odontogenic ghost cell tumor or odontogenic ghost cell carcinoma. We present a case of odontogenic ghost cell carcinoma with reference to the relation between the ghost cells and apoptosis. A 33-year-old man complained of a mandibular mass. The mass occupied the entire right side of the mandible with destruction of both buccal and lingual bone. The mass also infiltrated into submandibular and sublingual spaces. Histologically, the mass was composed of a solid proliferation of hyperchromatic and pleomorphic epithelial cells with abnormal mitoses. Islands of ghost cells were frequently admixed with nucleated cells, and there were foci of ameloblastic differentiation. Immunohistochemical stains for cytokeratins, involucrin, and apoptosis-related proteins such as Bcl-2, Bcl-X(L), and Bax were done. Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL) assay was also performed. The nucleated cells adjacent to the ghost cells expressed cytokeratins and involucrin, but the ghost cells had no reaction. Bcl-2 was negative. Both Bcl-X(L) and Bax were demonstrated in the nucleated cells adjacent to the ghost cells. The ghost cells exhibited Bax protein. Some nucleated cells adjacent to the ghost cells were positive with TUNEL assay. The above results indicate that ghost cells undergo abnormal terminal differentiation as an apoptotic process.     

Giant cell tumour of hyoid bone: case report

Giant cell tumours of bones are uncommon and are usually found in the epiphyses of long bones. They are rare in flat bones (<10%). The tumour has to our knowledge never been described in the hyoid bone, although 18 cases have been reported in the cartilagenous laryngeal skeleton. We report a giant cell tumour of the hyoid bone in a 45-year-old man, which we excised along with the left half of the hyoid bone. It recurred locally one year later and was cured by excision and split course radiotherapy. The patient is disease-free after 30 months of follow-up.     

Orbital infection arising from a primary tooth: a case report

Odontogenic infections may spread to the orbit by one or more of several paths. Such extension is potentially dangerous and may lead to loss of vision. A case of infection from a primary tooth, which extended to the retrobulbar area is presented in this report. Treatment included surgical drainage of the resulting subperiosteal orbital abscess through a Caldwell-Luc approach as well as aggressive antibiotic therapy. The importance of early suspicion of this entity and its potential sequelae are discussed.     

High-dose-rate mold brachytherapy of early gingival carcinoma: a clinical report

Two elderly edentulous patients with the diagnosis of early stage cancer of the upper gingiva were treated by customized dental mold brachytherapy. Locoregional tumor control was achieved in both patients. One patient is alive without any evidence of disease 36 months after treatment, the other patient died of distant metastasis shortly after brachytherapy. Brachytherapy, being easy to apply with short treatment time and good acute tolerance, is a good choice and effective modality for the management of early stage gingival cancer, particularly in elderly patients.     

Accuracy of implant impression splinted techniques: effect of splinting material

Three implant impression techniques, using 3 different splinting materials, were assessed for accuracy in a laboratory model that simulated clinical practice. For group A, an autopolymerizing acrylic resin was used to splint transfer copings. In group B, a dual-cure acrylic resin was used, and for group C, plaster, which was also the impression material, was used. A metal implant master cast with an implant master framework was made to accurately fit to the cast. This cast was the standard for all impressions. For each group, 15 impressions were made. Polyether impression material was used for groups A and B. The accuracy of the stone casts with the implant analogues was measured against the master framework, using strain gauges. A multiple analysis of variance with repeated measures was performed to test for significant differences among the 3 groups. Additional analyses of variance were carried out to locate the source of difference. The statistical analyses revealed that a significant difference existed between groups A and B and between groups B and C but not between groups A and C. Impression techniques using autopolymerizing acrylic resin or impression plaster as a splinting material were significantly more accurate than dual-cure acrylic resin. Plaster is the material of choice in completely edentulous patients, since it is much easier to manipulate, less time consuming, and less expensive.     

Managed Care in Dental Markets: Is the Experience of Medicine Relevant?

OBJECTIVE: This paper reports on factors that predict the market penetration and growth into the market of both medical and dental managed care, and the relationship between the two. METHODS: Using data from the National Association of Dental Plans, the Interstudy Competitive Edge HMO Census, and the Area Resource File from 1987-95, we created an analytic data base covering the dental HMO market, the medical HMO market, dentist and physician supply, and regional market characteristics. Simple correlation analysis and multivariate linear regression using ordinary least-squares techniques were used to predict medical HMO penetration and dental HMO penetration in each state during 1994 and 1995. RESULTS: The results show that although the penetration of dental HMOs has been modest when compared to medicine, its growth is predictable by the same factors, and closely follows the pattern found in medical markets. CONCLUSIONS: Despite the observed relationship between medical and dental HMO penetration rates, there are potential barriers to managed care in the case of dentistry that may explain the slower growth to date, and that may ultimately decide the extent of managed care penetration into the dental market.