Five-year longitudinal recordings of functional variables of the masticatory system in adolescents with intact and restored dentitions. A comparative anamnestic and clinical study.

Recordings of functional variables of the masticatory system were made in 184 subjects, 18-20 years old, 5 years after the first examination. One hundred and six subjects had restored dentitions at both examinations (group F), 35 subjects with previously intact dentitions had received fillings during the follow-up period (group FI), and 43 subjects had intact dentitions at both examinations (group I). In conformity with the first examination 5 years earlier, the subjects in group F had higher scores for dentin facets on the first lower molar. Together with the finding of more frequent attrition on the distal part of the occlusal surface of the second lower molar, this finding indicates more functional or parafunctional activity in restored dentitions. Unilateral contacts in the retruded contact position (RCP) were equally common in all three groups, but the contacts in RCP were more often located in the molar region in group F. The finding at the first examination that interference causing a lateral slide of the mandible between RCP and the intercuspal position (ICP) was commoner in restored dentitions was not confirmed in the present study. Nor did the correlation analysis show any relationship between occlusal factors and signs and symptoms of mandibular dysfunction. However, the differences found between subjects with intact and restored dentitions indicate that the iatrogenic effect of dental filling therapy merits more consideration and more extensive research.