Prediction of root resorption and periodontal tissue changes associated with rapid molar intruder

Document Type : Original Article

Authors

1 Department of Orthodontics, Faculty of Oral and Dental medicine, Cairo University.

2 Department of Orthodontics, Faculty of Oral and Dental medicine, El-Azhar University (Girl's branch).

3 Oral medicine, Periodontology and Radiology Department, Faculty of Oral and Dental medicine, Misr international University.

Abstract

Objective: Rapid molar intruder appliance (RMI), was used to close the anterior open bite by intruding upper and lower first molars. The aim of the present study was to investigate the amount of root resorption of first molars, as well as periodontal tissue changes associated with the application of RMI. Methods: Eleven female patients (mean age; 13-15 years) were included in the study. They had ANB angle average 5 degrees, with anterior open bite 1-3 mm. Root resorption and bone density were assessed using DBS win software, analyzing serial periapical radiographs of the first molars. Periodontal tissue changes were evaluated by measuring the probing depth, and sulcus bleeding and plaque indices. The records were compared with those of healthy, non- orthodontically moved first molars. Results: The upper first molar was intruded 1.9 mm, with 0.63 mm root resorption. While the lower molar intruded 0.5-0.7 mm, with root resorption of 0.7mm. No significant change in the periodontal variables was found. Conclusion: Rapid molar intruder is an efficient appliance for treating anterior open bite, causing minimal root resorption and maintaining the health of periodontium. The upper first molar is more favorable to be intruded, with significantly less apical root resorption, than the lower one.