Four hundred and six individuals from an unselected sample from the County of Stockholm aged 18-65 years in 1970 were examined radiographically in 1970 and 1980. The differences in proximal alveolar bone height were recorded, attention being paid to the divergences in projection between the two investigations. The mean of the alveolar bone difference was 5.5% of the mean root length, which corresponds to an average annual bone loss of 0.09 mm. Ninety per cent of the individuals had a difference in alveolar bone height of less than 10% of the root length--that is, an average bone loss of 1.6 mm or less during 10 years. By linear regression analysis it was shown that the difference in alveolar bone height is a function of the initial bone loss; that is, the greater the initial bone loss, the greater the alveolar bone loss during the 10-year period. The result of the regression analysis may facilitate predictions of alveolar bone loss.

No abstract

The diagnostic accuracy of panoramic and periapical radiography was compared by five oral radiologists who assessed the periapical status of 117 teeth evenly distributed throughout the jaws with a 50% probability that either an osteolytic or sclerotic lesion was present. Receiver operating characteristic (ROC) analysis demonstrated no overall significant difference between panoramic and periapical radiography. However, for sclerotic lesions and for all lesions on maxillary premolars and mandibular molars periapical radiography was significantly superior (P less than 0.001); it was also superior for osteolytic lesions in the maxilla as well as for the lesions on mandibular premolars but with a smaller significant difference (P less than 0.05).

No abstract

The purpose of the present study was to calculate the average anteroposterior size of the nasopharyngeal airway in 109 children (54 mouth breathers, in whom adenoidectomy was indicated for nasal obstruction, and 55 nose breathers) from 6 to 12 years of age, in order to obtain cephalometric standard; from these standards, one is able to judge the extent to which nose breathing may be obstructed. The results show when planning orthodontic therapy, in which it is desirable to assess the ability of the patient to breath through the nose, a clinical record of the mode of breathing can be supplemented with radiocephalometric data on the anteroposterior size of the nasopharyngeal airway.