Partial maxillary osteotomy following an unsuccessful forced eruption of\nan impacted maxillary canine - 10 year follow-up. Review and case\nreport
A 17 year old female patient was referred in 2001, after 31 months of orthodontic\ntreatment. On 12/29/1998, during this previous treatment time she underwent surgery,\nwhen a device was placed for orthodontic traction of the maxillary right canine,\nresulting in an unfavorable outcome. No notable particularities could be found, both\nupon current anamneses and a physical exam. In the course of the intra-oral exam, an\northodontic device could be seen with an open coil spring between teeth 12 and 14 for\nspace maintenance (). Tooth 13, with\ntransalveolar inclination, presented clinical exposure of its crown on the palate, with\nits vestibular face mesially rotated and three orthodontic buttons still present for\nelastic traction ().\nPeriapical and panoramic radiographic exams, dating from January 14, 2001, reveal\ntooth's 13 apex constrained within the ennis inverted Y. Significant bone loss could\nalso be seen distal to 12 and mesial to 14 (, ).\nPrevious history substantially reduced expectations for success in future attempts of\nsurgical orthodontic traction. Although the patient was well within a favorable age\n(13-19 years), proper orthodontic\ntreatment was conducted with space opening and well directed inter-arch elastic force\nfor much beyond the necessary time, without distinguishing signs of tooth movement.\nAfter the patient and her parents were advised about the possible prosthetic\nrehabilitation alternatives, they were favorable to the indication of partial maxillary\nosteotomy.\nThe appliance selection must conform to the orthodontist prescription. In addition, it\nis recommended that the brackets, with hooks or kobayashi on the posterior teeth, be\nproperly bonded and accessed for resistance. A rigid passive rectangular wire is\nnecessary, preferably .019"x.025". The arch-wire should be continuous in the mandibular\narch and segmented in the maxillary arch, separating the mesial and distal segments. The\nwire ends must be properly bent to protect the surgeon. A .025 mm steel ligature wire\nmay be used as a tie-together to stabilize the mesial and distal segments as rigid\nunits, not allowing individual tooth movements. Anterior hooks or kobayashi should be\nplaced in the upper and lower arches. Lastly, orthodontic buttons should be bonded on\nthe palatal side of the bicuspids on the distal segment, to allow for cross-bite\nelastics.\nThe surgery took place on March 02, 2001, under general anesthesia. The procedure was\ncomprised of the maxillary right canine removal and a partial maxillary osteotomy, with\nmobilization of the alveolar distal segment containing teeth 14 to 17. After the\northodontic wire was sectioned, bicortical osteotomies, vestibular and palatal, were\nperformed, on both the horizontal and vertical aspects. Fractures were performed with\nstraight and curved chisels, allowing for the liberation of the distal dento-alveolar\nsegment. Vertical osteotomies enabled the establishment of a breach in the alveolar\nprocess where the liberated segment was moved into, in a mesial direction, nearly\nclosing the gap. Aiming to preserve any residual viable periodontium, attention was\ngiven to maintain an approximate 1.5 mm margin of bone distal to 12 and mesial to 14.\nPost-surgically, by means of elastic traction, the approximation of the distal segment\nwas concluded. A single straight spaced 1.5 mm titanium miniplate with 4 holes, fixed\nwith 4 titanium miniscrews 4 mm long, was used for the osteosynthesis. Areas of ischemic\nformation of the gingiva could be observed during the suture, which were eliminated by\nresizing the traction elastics, thus reinforcing the significance of proper orthodontic\nanchorage.\nIntermaxillary immobilization was sustained for 21 days and during weekly postoperatory\ncontrols. When the elastics were removed and exchanged for new ones, mandibular movement\nwas encouraged. After three weeks, the segmented orthodontic arch-wire was substituted\nfor a continuous arch, maintaining stability of the segment and sustaining the formation\nof a callus.\nThe patient was cleared for orthodontic movements in April 24, 2001. Full treatment was\nconcluded on October 23, 2001, 7 months and 21 days later, with braces removal and\ninstallation of removable retainers. After 9.7 years, on October 29, 2010, due to\npatient request, the internal rigid fixation was removed. On the clinical and\nradiographic control of January 10 and 17, 2012 (, , , ), both stability and pulpar\nvitality could be confirmed after 10 years and 10 months of follow-up with excellent\nperiodontal conditions.