C. Guerrero

Mandibular widening by intraoral distraction osteogenesis

Transverse mandibular deficiency with crowding of the mandibular anterior teeth is frequently present in patients with Class I and II malocclusions. The hallmarks of treatment by compensating orthodontics, functional appliances or orthopaedic devices are instability, compromised periodontium and compromised facial aesthetics. A new surgical technique has been developed to widen the mandible. The method is based upon gradual osteodistraction following vertical interdental symphyseal osteotomy. Ten patients with transverse mandibular deficiency and significant dental crowding were treated by symphyseal distraction and subsequent non-extraction decompensating orthodontic treatment. Either an intraoral tooth-borne Hyrax appliance or a new custom-made bone-borne osteodistractor was used to gradually widen the mandible. The surgical procedures were accomplished under local anaesthesia and intravenous sedation in an ambulatory surgical setting using an individualized distraction protocol. The appliances were activated 7 days after symphyseal osteotomies, once each day at a rate of 1 mm per day and stabilized for 30-40 days after distraction. After the segments were distracted, non-extraction orthodontic alignment of the mandibular anterior teeth was accomplished. The symphyseal distraction gaps were bridged by new bony regenerate. Distraction osteogenesis provided an efficient surgical alternative to orthognathic surgery for widening the mandible and treatment of transverse mandibular deficiency without extraction of teeth.

Intraoral widening and lengthening of the mandible in baboons by distraction osteogenesis.

PURPOSE The purpose of this study was to analyze the skeletal and dental positional changes and histomorphology of the distraction regenerates and mucogingival periosteal tissues that occurred after simultaneous widening and bilateral lengthening of the mandible in baboons by a miniaturized intraoral bone-borne distraction appliance. MATERIALS AND METHODS Distraction appliances were activated 5 days after vertical ramus and symphyseal osteotomies at a rate of 0.9 mm/d for 10 days. The appliances were then stabilized for 8 weeks, after which the animals were killed. The distraction gaps and gingival tissues were analyzed clinically, histologically, and by standardized radiographic studies. RESULTS Positional changes of the canines and incisor apices were proportional to the skeletal movements. Tipping of both incisors toward the center of the distraction gap was observed. Proportionate movement of the superior and inferior portion of the distracted segments was noted. Newly formed longitudinal trabecular columns parallel to the vector of distraction originated from the intact margins of alveolar bone contiguous with the adjacent teeth. Active histogenesis occurred in the stretched mucogingival periosteal tissues located in the distraction gaps. CONCLUSIONS The results of this investigation support the clinical use of the miniaturized intraoral bone-borne distraction appliance to selectively widen and lengthen the mandible. The orientation of the mandibular distractors must be parallel to the common vector of distraction, which should be parallel to the maxillary occlusal plane. The formation of a bone regenerate in the alveolar region depends on the presence of an adequate bone interface on either side of the distraction gap.

Intraoral mandibular distraction osteogenesis

During recent years, distraction osteogenesis has gained in popularity for the treatment of various bone deficiencies either in the vertical, transverse, or anteroposterior dimension. Distraction osteogenesis has been shown to be an effective technique for mandibular widening and lengthening where traditional orthognathic surgery has important limitations. The intraoral approach to these procedures prevents damage to the inferior alveolar nerve and the developing dental follicles, and eliminates hypertrophic facial scars. Intraoral distraction osteogenesis also avoids donor-site morbidity, and minimizes the need for blood transfusion or prolonged fixation. This intraoral application provides for enhanced patient acceptance and reduces the potentially negative psychosocial effects of wearing an extraoral distraction appliance.

Cleft lip and palate surgery: 30 years follow-up

Ten cleft lip and palate patients with complete unilateral (five patients) and bilateral (five patients) clefts were treated by a multidisciplinary team integrated by psychologists, surgeons, orthodontists, prosthodontists, pediatric dentists, and speech pathologists, to obtain ideal soft tissue and hard tissue continuity, facial symmetry, functional and esthetic dentitions, excellent nasal architecture, subtle, and hidden lip scars. No hypernasality and adequate social adaptation were found in the 30 years follow-up (20-30 years follow-up with an average of 25.5 years). The patients were treated in a pro-active fashion avoiding complications and related problems, executing the ideal surgical, dental, and speech therapy plan, based on a close follow-up over the entire period. Those patients treated at the right time required less surgeries and less salvaging maneuvers and presented complete dentitions with less dental prosthesis or dental implants and stable occlusions, than those who missed the ideal dental and surgical treatment opportunities. The focus of this article is the need of a close long-term follow-up to ensure an ideal patients quality of life.

Mandibular Basal Osteotomy: New Designs and Fixation Techniques

PURPOSE This study evaluated the functional and cosmetic results of mandibular basal osteotomy, introducing new indications and fixation alternatives. MATERIALS AND METHODS Ten patients 19 to 46 years old (mean, 32.3 years) were treated by orthognathic surgery, including mandibular basal osteotomy for correction of deficiency, excess, or asymmetry of the inferior mandibular border. An intraoral approach based on 3 incisions to the anterior and posterior mandible was used to maintain and protect soft tissues surrounding the mental nerve. After marking the bone inferior to the nerve, a reciprocal saw completed the osteotomy design and individual rigid fixation according to movement was executed. All patients were 3-dimensionally treated and the evaluation included clinical, radiographic, and photographic analysis pre and postoperatively; all patients were followed for a minimum of 12 months. RESULTS All patients showed excellent functional and cosmetic results. Nine patients (9/10) were treated for advancement of the inferior border (mean, 6.89 ± 2.57 mm; P < .05). One of them underwent simultaneous inferior (3 mm) and lateral (4 mm) repositioning and 3 had combined lateral movement (mean, 3.5 ± 0.58 mm; P < .05). One patient (1/10) required posterior (4 mm) and inferior (5 mm) repositioning of the basal segment. CONCLUSIONS Mandibular basal osteotomy is an innovative technique that is strongly predictable for correction of deficiency, excess, and/or asymmetry of the inferior mandibular border, decreasing morbidity and many other complications of traditional bone grafts and alloplastic techniques.