The oral hygiene, gingival condition, pocket depth and loss of attachment were studied during a period of 5 years in a group of patients (114) who had been treated with fixed dental protheses. Eighty-four per cent of the subjects had received periodontal therapy prior to the prosthetic treatment. During the study the subjects participated in an oral hygiene programme. Crown margins were located sub-gingivally, at the gingiva, and supra-gingivally. Initially 65% of the crown margins were sub-gingival compared to 41% 5 years later. When the crown margins were located sub-gingivally there was an increase in Gingival Index scores 2 and 3, in pocket depth, and in loss of attachment compared to a supragingival placement. However, most of the alterations were small.

No abstract

A longitudinal study, extending over a period of 15 years, was carried out in a group of 102 patients who received 108 bridges made by the senior students at the Dental Faculty, University of Oslo, in 1967/68. The study included 343 abutment teeth, and the remaining teeth in the same jaw which received the restoration, 525 in all, served as control. The oral hygiene, gingival condition, pocket depth, caries on crowned teeth, location of crown margins and changes of alveolar bone level were recorded during the study. During the first 10 years, the patients received oral hygiene prophylaxis every 6 months. The mean age of the patients at the beginning of the study was 48 years. Of the original group of 102 patients, 88 attended the clinical examination after 5 years, 71 after 10 years, and 55 after 15 years. The amount of plaque did not differ between the crowned teeth and the control teeth during the observation period, while GI score 2 and 3 was more frequent in crowned teeth than in the control teeth during this period. This was mainly observed when the crown margins were located sub-gingivally. A slight increase in mean pocket depth was recorded in the crowned teeth while the mean pocket depth for the control teeth remained at the same level during the 15 years. Caries lesions were recorded in 3.3% of the abutment tooth surfaces at the 5th year, in 10.0% at the 10th year and in 12.0% at the 15th year examination. No statistical differences in bone loss could be detected between the control teeth and the crowned teeth.

There appears to be a relation between accumulation of plaque on complete maxillary dentures and denture stomatitis. The present index was introduced to assess the location and amount of plaque in some areas of the fitting surfaces of complete maxillary dentures. Scores were recorded in five defined areas on the denture base. Four ranked scores were used: 0 - no visible plaque, 1-plaque visible only by scraping on the denture base with a blunt instrument, 2-moderate accumulation of visible plaque, and 3-abundance of plaque. By summing up the scores from the five areas, the plaque was recorded on a scale from 0 to 15 points. The inter- and intra-reliability were tested for two examiners using the index on 50 complete maxillary dentures. Expressed in terms of Scott's Pi, inter-examiners agreement was 0.83, and intra-examiner 0.83 and 0.82 for examiners A and B, respectively. A simplification of the index was also presented. In this index the scores 0 and 1 were combined to score 0, -no visible plaque, and score 2 and 3 were combined to score 1, -visible plaque. Using this index, Scott's Pi was calculated to 0.91 for inter-examiner reliability. For the intra-examiners reliability Scott's Pi was calculated to 0.91 for examiner A and 0.89 for examiner B.

The purpose of the present study was to examine failures of fixed prosthodontics during a period of 15 years and to evaluate the quality of those bridges remaining after this period of time. The study group consisted of 102 patients who received 108 bridges made by the senior students at the Dental Faculty. University of Oslo, in 1967/68. All bridges were made of type-3 casting gold and heat-cured acrylic veneering. The mean age of the patients at the beginning of the study was 48 years. Of the original group of 102 patients, 88 attended the clinical examination after 5 years, 71 after 10 years, and 55 after 15 years. Of the 343 abutment teeth 25% were root-filled and restored with post and core. During the 15 years' observation period 26 bridges were lost or had to be remade because of failures. The mean time of service for these bridges were 10.5 years. The failure rate was 4% after 5 years, 12% after 10 years and 32% after 15 years. A modification of the CDA rating system was used for evaluation of the clinical quality of the restorations after 15 years. Between 5% and 14% of the units were recorded as 'not acceptable' for the different characteristics evaluated.