Observation Of Titanium Plate And Titanium Screw Removal And Coverage Status Following Orthognathic Surgery

Objectives: To investigate the motives behind titanium fixation plate removal following orthognathic surgery and to observe the coverage status of the titanium plate in order to know the optimal time for plate removal.Methods: Clinical files of 101 plate removal surgery patients who underwent plate removal following orthognathic surgery at the China Medical University School of Stomatology from 2015 to 2017.One-hundred and one patients were evaluated in this study,including 34 males and 67 females.Thirty-three had a bimaxillary operation and68 underwent mandibular osteotomy only.Age from 17 to 41 years old.The time between operation and plate removal ranged from 3 to 72 months(mean: 13.3 months).All patients were examined by X-ray to determine the situation of bone healing and the condition of the titanium plate.Preservation of the surrounding tissue around titanium plates by photographic preservation during the operation.During the operation of the observed titanium plate titanium nail around the organization of photographs retained.Data was collected and analyzed using Microsoft Excel.Statistical analysis was carried out using Fisher's exact test,with a p-value <0.05 being considered statistically significant.Results: Hardware was removed in 11 patients(10.9%)because of clinical symptoms.Ninety patients(89.1%)requested removal of asymptomatic plates.The reasons for asymptomatic plate removal were as follows: 48 patients(47.5%)feared metal in the body,28 patients(27.7%)did not want to have evidence of prior orthognathic surgery,and 14 patients(13.9%)feared interference with other tests,such as computed tomography(CT)and magnetic resonance imaging.Three tissue types were found intraoperatively surrounding the titanium plates;fibrous callus,bony callus and inflammatory granulation tissue.In the patients with mandibular osteotomy only,5patients were covered by granulation tissue,55 patients were covered by fibrous callus,4patients were partial covered by bony callus and 4 patients were complete covered by bony callus.And the severity of bone coverage and postoperative time was positively correlated.When the maxillary titanium plate was removed,1 patient was covered by granulation tissue,26 patients were covered by fibrous callus,3 patients were partial covered by bony callus and 3 patients were complete covered by bony callus.And the severity of bone coverage and postoperative time was also positively correlated.Conclusions: We found that most plates were removed in the absence of clinical symptoms because of patient request,which differs from most European and American countries.With prolonged postoperative time,the more serious the callus coverage,the greater the difficulty of plate removal.The optimal removal time of the maxilla is 12 to18 months and the mandibular removal is 6 to 12 months.Therefore,it is preferable to remove plates early,once the bone heals well,if patients request plate removal following orthognathic surgery.