[Narrowing of the dental pulp cavity in patients undergoing long-term administration of steroids]

The purpose of this study was to examine narrowing of the dental pulp cavity in patients undergoing long-term administration of steroids, by means of intraoral radiographs. The subjects were 20 patients under long-term steroid treatment (the steroid group), and 15 patients who were not receiving steroids (the non-steroid group), who visited the Clinic for Persons with Disabilities, University Hospital, Faculty of Dentistry, Tokyo Medical and Dental University, between April 1994 and March 2000. The dental pulp cavity was divided into the coronal area and the root area. Narrowing of each area was classified into three stages by means of intraoral radiographs (0, none; 1, moderate; 2, severe). Maxillary and mandibular dentition was divided, for purposes of analysis, into anterior, premolar, and molar areas, respectively. The narrowing of each part was statistically compared between the steroid group and the non-steroid group, using the Mann-Whitney U-test. Mean age +/- SD of the steroid group and the non-steroid group was 50.5 +/- 17.3 and 51.8 +/- 14.1, respectively. There was no significant difference in mean age between the steroid group and the non-steroid group (t-test). Narrowing of the dental pulp cavity in the steroid group was significantly greater than in the non-steroid group, except in the root area of the molar part. Since there was no significant difference in mean age between the steroid group and the non-steroid group, the greater narrowing in the steroid group was concluded to be attributable to the long-term administration of steroids.

Eight-year trend of new patients at Clinic for Disabled Patients, University Hospital, Faculty of Dentistry, Tokyo Medical and Dental University

The trend of new patients was investigated at the Clinic for Disabled Patients, University Hospital, Faculty of Dentistry, Tokyo Medical and Dental University for eight years from 1989 to 1996. The purpose of this study was to explore the future role of this specialized clinic. The study revealed the following information: 1. A total of 1,388 new patients, corresponding to 173.5 new patients per year on average, visited the clinic. 2. The percentage of patients aged 30 or more increased. As a result, the mean patient age rose from 40.4 in 1989 to 47.6 in 1996. 3. Referrals accounted for more than 80% of new patients. Medical doctors referred more patients to our clinic than dentists did. 4. While the percentage of disabled patients tended to decrease, the percentage of medically compromised patients increased. 5. The predominant complaint was dental caries. Patients with cardiovascular diseases also complained of gingival bleeding and ill-fitting dentures. The growing percentage of medically compromised patients and the increasing mean age of patients over the eight-year period seems to reflect advances in medical science and the aging society. These tendencies could be more remarkable in the future. Therefore, much closer cooperation between dentists and medical doctors will be required.

Stability of the mandibular position in occlusion of mandibulectomy patients with lateral discontinuity defect

In mandibulectomy patients with lateral discontinuity defect, the mandible is severely deviated and the occlusion is considered to be unstable. A thorough understanding of the mandibular occlusal position of these patients is important to achieve desirable results in their occlusal rehabilitation. This study compared the stability of the mandibular positions in occlusion, when the opening distance or the biting force was changed during mandibular movements, by simultaneously measuring four points on the mandible three-dimensionally. This study indicated that the mandibular positions in occlusion of these patients were extremely unstable as compared with those of the normal subjects and were considerably different from each other when the opening distance or the biting force was changed during mandibular movements.

Defective neutrophil chemotaxis in Down's syndrome patients and its relationship to periodontal destruction

The degree of defective neutrophil chemotaxis in patients with Down's syndrome (DS) and its relationship to the severity of periodontal disease were studied. Fourteen patients with DS and 14 healthy controls were examined. Oral hygiene, gingival inflammation, and pocket depths were measured in clinical surveys. Bone loss was evaluated on the oral radiographs. Neutrophil chemotaxis was measured by the agarose plate method and the Boyden chamber method. The chemotactic index of the agarose plate method and the mean numbers of migrated cells of the Boyden chamber method were correlated with statistical significance (rs = 0.066, P less than 0.01). DS patients showed significantly lower chemotaxis than healthy volunteers with both methods. No difference was shown between the two groups in the random migration of the neutrophils. From the oral radiographic analysis, the DS patients exhibited various prevalence of bone loss which was inversely proportional to the chemotactic index and a significant correlation between them was shown (rs = -0.612 P less than 0.05). A significant correlation was also found between the age of the patient and the prevalence of bone loss (rs = 0.591 P less than 0.05). These results indicate that defective neutrophil chemotaxis influences the progression of periodontal disease in DS patients.