Long-term results of bilateral mandibular distraction osteogenesis using an intraoral tooth-borne device in adult Class II patients.

The aim of this prospective clinical study was to evaluate the short-term and long-term skeletal and dental changes after mandibular osteodistraction with tooth-borne appliances in adult orthodontic patients. The sample consisted of 10 non-growing Caucasian patients with a Class II skeletal relationship due to mandibular deficiency, together with Class II dental malocclusion. All patients underwent mandibular distraction osteogenesis (MDO) using the ROD1 tooth-borne device. Lateral cephalograms were evaluated at four time intervals: pretreatment (T1), after mandibular distraction (T2), after orthodontic fixed appliance therapy (T3), and at long-term observation 8-year post-distraction (T4). Statistical analyses compared the skeletal and dental changes in intervals T1-T2, T2-T3, T3-T4, T1-T4, and T2-T4. MDO with the ROD1 tooth-borne device produced significant long-term (T1-T4) increases in the SNB angle (2.3°), total mandibular length (5.9mm), and corpus length (4.5mm). Potential adverse sequelae included significant increases in mandibular plane angle (4.3°), lower anterior dental height (2.8mm), and lower posterior dental height (2.5mm). Significant increases in lower incisor proclination occurred during distraction (7.5°). Distraction osteogenesis with tooth-borne appliances offers a minimally invasive surgical method with stable results for correcting mandibular deficiency in non-growing patients.

Treatment modalities of TMJ ankylosis: experience in Delta Nile, Egypt.

The study reports the authors' experience in managing TMJ ankylosis in Delta Nile, Egypt (1995-2006) and compares the surgical modalities used. 101 patients (109 joints) were reviewed in this retrospective study. Pre- and postoperative assessment included history, radiological and physical examination, and mouth opening. Age, sex, aetiology, joint(s) affected, surgical modality, complications and follow up periods were evaluated. Various types (fibrous, fibro-osseous and bony) of TMJ ankylosis were diagnosed; trauma was the commonest aetiology. The patients' age range was 2-41 years, 62% were female, and the follow up period ranged from 14 to 96 months. Average mouth opening was significantly increased from 5.3mm pre-operatively to 32.9 mm 12 months postoperatively (P=0.0001). Marked improvement in mouth opening was documented when the ramus-joint complex was reconstructed using distraction osteogenesis (34.7 mm), costochondral graft (34.4mm) and Surgibone (34.6mm). Gap arthroplasty showed least satisfactory mouth opening compared with other techniques (P=0.001). Minor and major complications were encountered in 33% of cases, including 5% recurrence rate. Early release of TMJ ankylosis; reconstruction of the ramus height with distraction osteogenesis or bone grafting combined with interpositional arthroplasty, followed by vigorous physiotherapy is successful for managing TMJ ankylosis.

Effects of ultrasound modes on mandibular osteodistraction.

Previous studies have shown that therapeutic pulsed ultrasound (pulsed) has superior stimulatory effect on bone fracture healing compared with continuous ultrasound (continuous). Our predictive hypothesis was that pulsed ultrasound can produce better bone formation during mandibular osteodistraction than continuous ultrasound. Thirty-six New Zealand rabbits were divided into 3 groups of 12. Osteodistraction was performed at 3 mm/day for 5 days. Group 1 received pulsed, group 2 received continuous ultrasound, and group 3 was the control group (distraction only). Bone formation was assessed by quantitative bone density (QBD), mechanical testing, and histological examination. In the first 2 wks post-distraction, group 2 showed enhanced bone formation more than group 1 (p < 0.05); however, in the 3rd and 4th wks, group 1 showed more bone formation than group 2 (p < 0.05). Earlier stages of bone healing were enhanced more by continuous, whereas late stages were enhanced more by pulsed, ultrasound.

Platelet rich plasma may enhance peripheral nerve regeneration after cyanoacrylate reanastomosis: a controlled blind study on rats.

The aim of this study was to explore the ability of platelet rich plasma (PRP) to promote peripheral nerve regeneration after cyanoacrylate reanastomosis in rats. A total of 18 rats were used in this study. Bilateral sciatic neurotomies were performed in 15 rats, and then immediately reanastomosed with cyanoacrylate glue. On one side (G1), the anastomosed nerves were treated with prepared autologous PRP gel; on the contralateral side (G2) the nerves received no additional treatment. Sham surgery was undertaken on the remaining 3 rats (6 cases) where bilateral sciatic nerves were surgically approached but not cut (passive control group, (G3). Biopsies were harvested 12 weeks postoperatively and examined under the light microscope using osmic acid stain. The number of nerve fibers in the distal and proximal nerve segments of G1 and G2 as well as in G3 were counted and the results analyzed and compared. Animals in G1 and G2 showed some weakness and ulceration in their right and left feet for a few weeks postoperatively, which gradually improved during the follow-up period. The histomorphometric assessment showed a higher axon count in the distal segment of G1 (291.7 axons) compared with that of G2 (280.5 axons) (P=0.001). Similar results were noticed when the proximal segments of both groups were compared (P=0.040). These results were reflected in the values of the neurotization indices of G1 (91.9%) and G2 (89.5%) (P=0.008). The number of nerve fibers in G1 and G2 remained lower than in G3 (P=0.0001). The authors conclude that PRP may enhance the number of regenerating nerve fibers after cyanoacrylate neruoanastomosis.

Aspiration of an impacted lower third molar during its surgical removal under local anaesthesia.

In this case of an aspirated impacted lower third molar during its removal under local anaesthesia, the problem was recognized immediately during the surgical procedure. The patient, a 23-year-old male, was subjected to urgent radiological examination. The aspirated tooth was detected in the right bronchus and eventually removed by rigid bronchoscopy. Oral surgeons should suspect any tooth that has been avulsed or extracted and not found as having been aspirated. Early diagnosis and management of such incidents is essential.

Intraoral distraction osteogenesis for the correction of facial deformities following temporomandibular joint ankylosis: a modified technique.

The aim of this study was to evaluate the feasibility of transoral bimaxillary distraction osteogenesis before releasing temporomandibular joint (TMJ) ankylosis using intraoral mandibular distractors. Nine patients (5 males, 4 females) aged 14-35 (mean 19) years were included. A bilateral Le Fort I osteotomy was performed together with a mandibular osteotomy on the affected side(s). An intraoral distractor(s) was inserted in the lower jaw, followed by an intermaxillary fixation (IMF) to maintain preoperative dental occlusion. The distractor was activated, after a latency period of 5-7 days, 2 times daily by 0.5 mm. There followed a consolidation period of 6-8 weeks. TMJ ankylosis was then released via a peri-auricular incision, a gap arthroplasty was performed, and mandibular movement was established after removal of the IMF and distractor. Optimal results were achieved clinically and radiologically with minimal relapse and complications. Apart from minor complaints, the distraction process was smooth and tolerable in all cases. Total mandibular elongation ranged from 17 to 25 mm (20.7 mm). Occlusal canting decreased to 0 degrees in 7 patients and to 1 degree in 2 patients (mean 0.2 degrees). After a mean follow-up period of 17 months, a mean postoperative mouth opening of 34.7 mm was achieved (0.6 mm preoperatively) and no re-ankylosis was detected. Intraoral distraction of a deformed mandible and maxilla before releasing TMJ ankylosis is a feasible and perhaps advantageous technique.