CRANIOFACIAL STRUCTURE AND SOFT-TISSUE PROFILE IN PATIENTS WITH SEVERE HYPODONTIA

This study compares craniofacial structure and soft tissue profile in persons with mild hypodontia (group I: 2 to 5 congenitally missing tee th, n = 43), moderate hypodontia (group II: 6 to 9 congenitally missin g teeth, n = 15) and severe hypodontia (group III: 10 or more congenit ally missing teeth, n = 29) with the structure of persons without hypo dontia and with normal occlusion (n = 50). The mean age was about 12 y ears. In group I, the lower second premolars were the most frequently missing teeth, followed by the upper second premolars and the upper la teral incisors. The relative prevalence of missing second premolars de creased with increasing severity of hypodontia. No consistent pattern could be observed when more than five teeth were missing, indicating a different genetic mechanism than for mild hypodontia. A significant r etroclination of the incisors and an increased interincisal angle were observed with increasing severity of hypodontia. This was accompanied by a reduction of lip protrusion, being most evident for the upper li p. Increasing numbers of missing teeth resulted also in a decrease in the mandibular plane angle and a reduction in the anterior lower facia l height. Few differences in the skeletal parameters were observed. It was concluded that the typical dentofacial structure in persons with advanced hypodontia may be due to dental and functional compensation r ather than to a different growth pattern.