Title:  Case report: severe infraocclusion ankylosis occurring in siblings

Abstract:  Aim This was to report a rare case of strong familiar tendency of ankylosis of maxillary second primary molars. Case report Three Caucasian children, male twins of 8.5 years and a sister of 10 years, were diagnosed as having severely infraccluded maxillary second primary molars with underlying second premolars. In all three cases, the early extraction of the infraoccluded molars and an active treatment with cervical extraoral traction allowed the physiologic eruption of second premolars. Follow-up showed that normal vertical relationship and bone height had been obtained. Conclusion Early diagnosis, as well as appropriate treatment and careful follow-up are very important in the presence of severe infraocclusion, when the marginal ridge of affected primary teeth is at or below gingival level.