Comparative study of stability between two different fixation systems after orthognathic surgery in mandibular prognathism skeleton.

OBJECTIVE: This study is intended to compare the skeleton stability of bioabsorbable and titanium systems after orthognathic surgery in mandibular prognathism patients. STUDY DESIGN: A Retrospective study of 28 mandibular prognathism patients who underwent BSSRO setback surgery at Chulalongkorn University. Both titanium and the bioabsorbable group would take lateral cephalometrics immediately postoperative in 1-week(T0), 3(T1), 6(T2), and 12(T3) months. These radiographs were analyzed with Dolphin imaging programTM. The vertical, horizontal, and angular indices were measured. To compare immediately postoperative and follow-up periods within the group, the Friedman difference was used, and the Man-Whitney U test was used between the two groups. RESULT: The measurements within the group presented no statistically significant differences. But this study showed that at T0-T1, there was a statistically significant difference between the two groups in the mean of Me in horizontal linear measurement. T0-T2 found differences between Me in both horizontal and vertical linear measurements, and the difference between ANB. The differences between B-point, Pog, and Me in vertical linear measurements at T0-T3 were also reported. CONCLUSION: The significant difference values were within the normal range which indicated that using the bioabsorbable system could be well maintained as well as the titanium system. STATEMENT OF CLINICAL RELEVANCE: The second operation for removing titanium plate and screw after conventional orthognathic surgery may leads patient discomforts. While a resorbable system might be the role change if the stability is place on the same level.