TIMING OF EXCHANGE OF THE MAXILLARY DECIDUOUS AND PERMANENT TEETH IN BOYS WITH 3 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 unilate ral cleft (UCLP), 82 boys with bilateral cleft (BCLP), and 97 boys wit h 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 per manent maxillary second molar was retarded on the cleft side, On the n onaffected side, no delay of eruption was observed, but earlier erupti on was found in the permanent maxillary canine and in the permanent ma xillary first and second premolars. In boys with BCLP, the highest ret ardation of eruption was found in the permanent maxillary lateral inci sor and in the permanent maxillary first molar, The permanent maxillar y canine and both permanent maxillary premolars erupted earlier than i n the control group, In boys with CP, only the permanent maxillary cen tral incisors erupted earlier. The maxillary deciduous canines and the second molars were both lost early, we conclude that the developmenta l disturbances of the maxillary jaw and teeth in patients with orofaci al clefts are also associated with alteration of timing of dental exch ange.