Facial and dental changes in adulthood.

The purpose of this longitudinal investigation was to study the dentofacial changes occurring between 25 and 46 years of age in an untreated normal sample. Measurements were made from cephalograms and dental casts available on 15 women and 15 men at age 25 and 46 years. The findings indicate that females exhibited significant increases in all skeletal facial linear dimensions, a decrease in cranial base angle and mandibular prominence, an increase in skeletal convexity and facial divergence. Most of these changes were of relatively small magnitude. Over the span of the study, significant crowding occurred in the mandibular arch. Males exhibited similar significant increases in all skeletal linear dimensions, a decrease in cranial base angle, and increases in maxillary skeletal prominence and skeletal convexity. Increased crowding with age was seen in both maxillary and mandibular arches. In conclusion, the findings indicate that a clinically significant increase in tooth size-arch length discrepancies occurred between 25 and 46 years of age. These changes should be considered as part of the normal "maturational" process. Furthermore, the relative changes in the position of the lips, nose, and chin, cause the lips to appear more retrusive at 46 years of age. These changes should be taken into consideration when orthodontists are considering various treatment and retention options for their adult patients.