Maxillary central incisors were replanted in ten vervet monkeys after an extra-alveolar time (EAT) of two hours during which the teeth were kept moist with a saline solution. Intramuscular thyrocalcitonin was administered to the experimental group, but not to the control group to assess the effect of thyrocalcitonin on the postoperative ankylosis, which was expected to occur after an EAT of two hours. The preoperative mobility was noted in all of the teeth that were planned for replantation by a technique known as periodontometry. The postoperative changes in mobility were similarly recorded at weekly intervals for eight weeks. Thyrocalcitonin did not alter the mobility of the teeth after replantation when compared to the teeth replanted in the control group. Maxillary central incisors were replanted in ten vervet monkeys after an extra-alveolar time (EAT) of two hours during which the teeth were kept moist with a saline solution. Intramuscular thyrocalcitonin was administered to the experimental group, but not to the control group to assess the effect of thyrocalcitonin on the postoperative ankylosis, which was expected to occur after an EAT of two hours. The preoperative mobility was noted in all of the teeth that were planned for replantation by a technique known as periodontometry. The postoperative changes in mobility were similarly recorded at weekly intervals for eight weeks. Thyrocalcitonin did not alter the mobility of the teeth after replantation when compared to the teeth replanted in the control group.