Relationship between clinical periodontal condition and the radiological appearance at 1st molar sites in adolescents. A 3-year study.

There has been considerable controversy about the incidence of periodontal disease in adolescents. It is noteworthy that there is disagreement between workers as to be radiological features that should be used to detect the earliest signs of periodontitis, and variation in the choice of criteria may have influenced the results of previous studies. The present project represents a 3-year longitudinal assessment into the periodontal condition, assessed clinically and radiologically, of a group of adolescents. The radiographic investigations were carried out using vertical bitewing radiographs and, to reduce potential error caused by variation in film placement and tube alignment, individual impressions were used so that the film could be positioned accurately at repeat assessments. It was found that several of the radiographic features, such as the width of the periodontal ligament space and the angle of the interproximal bone crest relative to the tooth, similar to those previously attributed to the commencement of destructive periodontal changes, were found to be correlated with the maturation changes associated with the eruption of the adjoining permanent teeth. In spite of the use of impressions, some of the series of radiographs showed variation in tube alignment, and several of the above radiological features were also found to correlate with errors in radiographic technique. It was concluded that the various eruptive and maturation changes taking place during this stage in the adolescent dentition must be allowed for when looking for the earliest signs of periodontal destruction.