Multiple occurrences of the submerged primary molars are relatively rare compared to the cases of one or two teeth.
This is a case report of the submergence occurred in all eight primary molars of a 7 year-4 month-old Japanese girl.
The patient was referred to the Pedodontic Clinic of Tsurumi University Dental Hospital for the treatment of the masticatory dysfunction due to the total submergence of the primary molars.
Clinical examination revealed masticatory dysfunction and lateral tongue thrusting as a result of the posterior open bite caused by the total submergence, and the functional anterior cross bite resulted from incisal mastication.
The submergence of these primary molars increased in severity as the eruption of the permanent first molars and the permanent incisors proceeded. The masticatory dysfunction was treated by constructing overlay dentures after stainless steel crown restorations were rendered on these eight primary molars.
The follow-up cephalometric tracing showed that these primary molars stayed in the same position, while the upper and lower first permanent molars grew vertically, indicating clearly that the submergence is mainly caused by the vertical growth of the adjacent teeth and their supporting tissues.