Effect of masticatoiy stimulation on dentoaiveolar ankylosis after experimental tooth replantation Andersson L, Lindskog S, Blomlof L, Hedstrom K-G, Ham- marstrom L. Eflect of masticatory sliuuilation on dentoaiveolar ankylosis after experimental tooth replantation. Endod Dent Traumatol 1985; 1: 13-6. Abslract - Denloalveohtr ankylosis (replacement resorption) is a serious eomplieation afti-r replantation of avulsed teeth. The pur- pose of the present study was lo investigate the influence of mastieatory stimulation on dentoaiveolar ankylosis after replant- ation of avulsed teelh. Monkey upper incisors were extracted, air-dried for 1 h, endodontically treated and replanted. No splinting was used. One grou]) of monkeys was given hard pel- leted food, while another group was given soft diet during a healing period of 8 wk. The periodontal conditions were evalu- ated histologically with a morphometrieal method. The re- |)lanted leeth of the monkeys given the hard pelleted lood had significantly less ankylosis and a larger area of the root sur- rounded by a normal periodontal membrane than the teeth from the monkeys given a .soft diet. In conclusion, development oi ankylosis seemed to be partially prevented or reduced by masti- catory stimulation. Lars Anderssen, Sven Lindsi(eg, Leif Biemldi, Kari-Goran Hedstrom and Lars Hammarstrom Departtnetit ot Oral Pathology, School ot Dentistt^, Karolitiska Institute, Departtnetit ol Oral Surgery, Sodersjukhuset, Department of PeriotJontology. Skanstull, Public Dental Service, and National Bac- teriological Laboratory, Primate Research Center, Stockholm, Sweden Key words: ankylosis, replantation, root resorption, masticatory stimulation. Dr. S. Lindskog, Dept. ol Oral Pathology, School ol Dentistry, Karolinska Institutet, Box 4064, S-14t 04 HutJdinge, Sweden. Accepted tor publication 8 October t984. Dentoaiveolar ankylosis (re]:)laceinent resoriJtioii) is a common and serious complication alter replant- ation of teeth with injured periodontal membianc (1-8). Ankyloscd teeth are incorporated in the nor- mal remodelling |)ro( ess of the alveolar Ixnie and progressively resorbed (8, 9). In addition ankylosis may result iti an incomplete cle\i'lo|3nicnt ol the alveolar processes if the ankylotic fusion occurs at an early age (10). A rigid splinting of a replanted (t)oth has been shown (o |3roniote the de\'elopment of ankylosis (11, 12). This indicates that ftmctional stimulation plays an ini|3ortanl loli- during |)eri()dontal healing after replantation. It also indicates that ankylosis may be prevented or even eliminated by mastieatory stimulatioti. However, exeessive stimulation due to occlusal liauina does nol seem to eliminate or j^re- vent ankylosis in teeth reijlaiUed after long extraoral ]jeriods (13). The purpose of the present experiment was to study the effect of normal masticatory stimulation on periodontal healing of replanted teeth expected to become ankylolic and lo compare the cilect of normal masticalory stimulation with results from teelh thai have recicved no or minimal masticatory slimitlation. iVIateriai and metiiods Expenmental animals Ten, 3- to 4-year-old monkeys {Macaca fascicutaris), were used in the experimenl. On the day of extrac- tion and replantation all animals were gi\en only bananas. From the day after replantalion and throughout the healing period 5 of the animals were given hard pellets (Astra Ewos, Sodertalje, Sweden) and fruit. The remaining 5 monkeys were given the .same kind of food but of a .soft consistency ihiotigh- out lhe healing period. The soft diet consisted of hard pellets soaked in water for 1 h in order to give them a soft porridge-like consistency. The monkeys in the soil diet group were also given the same kind 13