Abstract
The purpose of this study was to investigate the influence of fused primary teeth and congenitally missing primary teeth on the eruption of the permanent successors and on the development of the permanent dentitions. Dental casts and clinical records of thirty children who had fused teeth or congenitally missing teeth among their mandibular primary anterior teeth were used in this study.
The following results were obtained. Ten cases had normal successors in their permanent teeth. In two of those cases, four permanent incisors were aligned between both primary canines. In the other cases, the primary canines exfoliated or were extracted when the lateral incisors erupted. Lingual arches were set to maintain the space for permanent teeth for the most of those cases, resulting in a fairly good alignment of the permanent dentitions.
In the cases with fused successors and the cases without successors, most of the fused primary teeth or teeth adjacent to the missing teeth exfoliated spontaneously, followed by the eruption of the successors. Over bite or over jet of most of those cases in permanent dentitions were rather large. Although many cases had interdental spaces in their mandibular permanent dentitions, most of the spaces were located between a canine and a first premolar or between posterior teeth. Only one case with two missing anterior teeth developed a large diastema and was provided with orthodontic treatment and prosthodontic treatment.
