Timing of exchange of the maxillary deciduous and permanent teeth in boys with three types of orofacial clefts.

Timing of exchange of the deciduous and permanent maxillary teeth was investigated using dental plaster casts of 163 boys with total unilateral cleft (UCLP), 82 boys with bilateral cleft (BCLP), and 97 boys with isolated cleft palate (CP). All patients were treated at the Prague Plastic Surgery Clinic. The results were compared with a control group of 294 schoolboys. To evaluate the course of eruption, the proportion of each erupted teeth in each year of age was employed. In boys with UCLP, eruption of the permanent maxillary lateral incisors and the permanent maxillary second molar was retarded on the cleft side. On the non-affected side, no delay of eruption was observed, but earlier eruption was found in the permanent maxillary canine and in the permanent maxillary first and second premolars. In boys with BCLP, the highest retardation of eruption was found in the permanent maxillary lateral incisor and in the permanent maxillary first molar. The permanent maxillary canine and both permanent maxillary premolars erupted earlier than in the control group. In boys with CP, only the permanent maxillary central incisors erupted earlier. The maxillary deciduous canines and the second molars were both lost early. We conclude that the developmental disturbances of the maxillary jaw and teeth in patients with orofacial clefts are also associated with alteration of timing of dental exchange.