Doğan Dolanmaz

Intraosseous Screw–Supported Upper Molar Distalization

The aims of the present study were to investigate (1) the efficiency of intraosseous screws for anchorage in maxillary molar distalization and (2) the sagittal and vertical skeletal, dental, and soft tissue changes after maxillary molar distalization using intraosseous screw-supported anchorage. Twenty-five subjects (18 girls and seven boys; 11.3 to 16.5 years of age) with skeletal Class I, dental Class II malocclusion participated in the study. An anchorage unit was prepared for molar distalization by placing an intraosseous screw behind the incisive canal at a safe distance from the midpalatal suture following the palatal anatomy. The screws were placed and immediately loaded to distalize upper first molars or the second molars when they were present. The average distalization time to achieve an overcorrected Class I molar relationship was 4.6 months. The skeletal and dental changes were measured on cephalograms and dental casts obtained before and after the distalization. In the cephalograms, the upper first molars were tipped 8.8 degrees and moved 3.9 mm distally on average. On the dental casts, the mean distalization was five mm. The upper molars were rotated distopalatally. Mild protrusion (mean 0.5 mm) of the upper central incisors was also recorded. However, there was no change in overjet, overbite, or mandibular plane angle measurements. In conclusion, immediately loaded intraosseous screw-supported anchorage unit was successful in achieving sufficient molar distalization without major anchorage loss.

A Preferable Technique for Protecting the Inferior Alveolar Nerve: Coronectomy

PURPOSE The aim of this study was to evaluate the effectiveness of coronectomy for teeth whose root apices are very close to the inferior alveolar canal. PATIENTS AND METHODS The 43 patients of this study needed removal of their lower third molar, whose root apices were very close to the inferior alveolar canal. These patients underwent 47 coronectomies. RESULTS The mean follow-up period was 9.3 months (range, 1 to 48 months). The mean total amount of root movement was 3.4 mm at 6 months, 3.8 mm at 12 months, and 4.0 mm at 24 months. CONCLUSIONS The technique of coronectomy is defined as removing the crown of a tooth but leaving the roots untouched, so that the possibility of nerve damage is reduced. Coronectomy is a preferable technique for patients who run a risk of injury to the inferior alveolar nerve during third molar surgery.

Distraction osteogenesis of basal mandibular bone for reconstruction of the alveolar ridge

Alveolar distraction is being used increasingly for alveolar bone reconstruction in patients with severe mandibular defects. When there has been total loss of alveolar bone, distraction of the mandibular basal bone is necessary. Distraction osteogenesis is considerably more challenging in mandibular basal bone than in alveolar bone. The low level of the cut increases the technical difficulty and may result in a poor outcome. We describe three cases in which more than 10 mm of distraction of mandibular basal bone was required. Semirigid distraction devices were used to reconstruct the alveolar structures in each case.

Comparison of stability of absorbable and titanium plate and screw fixation for sagittal split ramus osteotomy

Six unembalmed adult sheep mandibles were stripped of all soft tissues and sectioned at the midline. Each side had a sagittal split ramus osteotomy (SSRO) and was advanced 5 mm. Six of the hemimandibles were fixed with four-hole extended titanium miniplates and titanium screws, and the other six were fixed with four-hole extended absorbable plates and absorbable screws. All specimens were mounted in a servohydraulic testing unit, and a range of forces (0-140 N) was applied. Displacement of each proximal segment was recorded at 10 N increments from 0 to 140 N. Values for the two groups were compared using the Mann-Whitney U-test, and significant differences in displacement were seen only at loads between 10 and 50 N. The results indicate that when absorbable miniplates are used intermaxillary fixation may be necessary to stabilise the bony fragments in the early postoperative period.

Maxillary anterior segmental advancement by using distraction osteogenesis: a case report.

After the first clinical application of distraction osteogenesis (DO) to correct mandibular deformity was reported in 1992, various applications such as maxillary or midface advancement, temporomandibular joint reconstruction, alveolar augmentation, and mandibular widening have been described in the oral and maxillofacial region. Block et al and Altuna et al first examined anterior segmental DO experimentally in the maxilla and reported successful results. After these studies, DO has been used clinically for the total advancement of the maxilla or midface. But no clinical application of DO for maxillary anterior segmental advancement was found by a review of the literature in English. In this article, we present a case with a skeletal Class III abnormality resulting from a maxillary deficiency, which was treated by using anterior segmental DO.

Management of Alveolar Clefts Using Dento-osseous Transport Distraction Osteogenesis

This article evaluates the usage of distraction osteogenesis (DO) in the treatment of cleft alveoli. The procedure was carried out on eight alveolar clefts of five patients between the ages of 17 and 25 years. Three patients had bilateral alveolar clefts (BAC) and two patients had unilateral alveolar clefts (UAC). DO was carried out bilateral to the palatal segments for the BAC patients and unilateral to the lesser segment for the UAC patients. A custom-made tooth-borne distractor was used. The average amount of distraction was eight mm (range, 5-11.5 mm). The average amount of distal movement of the anchorage teeth was 0.8 mm (range, 0-2 mm). The average amount of inclination changes of the transport segments and anchorage teeth was 7.6 degrees (range, 2-17.5 degrees) and 3.3 degrees (range, 0-9 degrees), respectively. Two important problems were observed attributable to the method. First, the transport segment was docked in a more superior position at the end of distraction process. This undesirable movement also changed the inclination of the teeth in the transport segment and increased tooth tipping. Removing the device in the second week of the consolidation period and retracting the segment to its ideal position orthodontically solved these problems. Second, the bony defect on the nasal side of the alveolar cleft could not be completely closed. This method for repairing small or large alveolar clefts is a simple, cost-effective, and useful treatment option. However, repairing the alveolar cleft without grafts seems to be impossible when using a tooth-borne device.

Rapid Canine Distalization through Segmental Alveolar Distraction Osteogenesis

OBJECTIVE The objectives of this study were to achieve rapid canine distalization by segmental alveolar distraction method in first premolar extraction cases, to examine the changes in the periodontal tissues surrounding canines, to evaluate the displacement of the canine and first molar teeth, to assess the effects of the procedure on the pulpal vitality of the canines, and to determine the amount of root resorption in retracted canines. MATERIALS AND METHODS The sample of the study consisted of 20 teeth in eight patients (four females and four males, mean age 18.5 years). Pre- and posttreatment dental casts, panoramic radiographs, and standard periapical radiographs were taken from all patients. An electrical vitality test was applied before and after the distraction procedure and during the follow-up period (6 months after the completion of the procedure). In addition, six periodontal indices were used to examine the health of the periodontal tissues. RESULTS The distraction procedure was completed in 12 to 28 days (mean 14.65 +/- 3.49). The anchorage loss ranged from 0 to 3 mm (mean 1.2 +/- 0.83). The distal displacement of the canines ranged from 3 to 8 mm (mean 5.35 +/- 1.22). The canines showed a mean of 9.1 degrees distal tipping, whereas there was no statistically significant change in the axial inclinations of first molars after distraction. CONCLUSION We believe that rapid canine distalization by segmental distraction osteogenesis will become a routine protocol and a popular method among orthodontic applications.

Histomorphometric Evaluation of the Effects of Zoledronic Acid on Mandibular Distraction Osteogenesis in Rabbits

PURPOSE To assess the effect of systemic administration of zoledronic acid (ZA) on mineralization of newly formed bone and to determine strain-related osteoporosis on surrounding bone during lengthening of immature rabbit mandible. MATERIALS AND METHODS Eighteen New Zealand white rabbits were divided randomly into 2 groups, and bone lengthening was carried out in the left portion of the mandible through distraction osteogenesis with a rate of 0.5 mm every 12 hours for 5 days. The experimental group was administered 0.1 mg/kg ZA intravenously. The control group was given saline infusion only during operation. All animals were sacrificed at the end of the 28-day consolidation period. The mandibles of all animals were removed and regenerate was evaluated. Osteoblasts, osteoclasts, collagen fibers, and fibroblasts were marked within 0.1-mm(2) area and newly formed bone area was measured within 0.5-mm(2) area. All data were analyzed using Mann-Whitney U test. RESULTS Although irregular bone destruction spots were seen in the control group, the experimental group showed regular ossification areas and significant difference between osteoblast and osteoclast numbers (P < .05). In the regenerate zone, there was considerable difference between the 2 groups in terms of osteoblast, osteoclast, and collagen amounts (P < .05). Additionally, newly formed bone areas and fibroblast count were higher in experimental group. CONCLUSIONS The results of this study showed that ZA had positive effects on the new bone formation, which may potentially shorten the consolidation period.

Effects of recombinant human erythropoietin on mandibular distraction osteogenesis.

PURPOSE To evaluate the effects of subcutaneous administration of recombinant human erythropoietin (rHuEPO) on regeneration formation and quality during mandibular distraction osteogenesis. MATERIALS AND METHODS Sixteen adult male New Zealand rabbits were used in this study. Ethical approval was obtained from the Animal Research Institute of Selcuk University, Konya, Turkey. Subjects were randomly divided into 2 groups. Distraction osteogenesis (DO) was performed with a custom-made distractor on the left mandibles of rabbits. In the experimental group, 4 doses of 150 IU/kg rHuEPO were administered at 48-hour intervals. The first dose was given immediately after surgery. Control subjects received 0.5 mL/kg isotonic solution in the same manner. After 2 days of latency, mandibles were distracted 1 mm/day at 12-hour intervals for 5 days. A 5-mm lengthening was achieved. All animals were sacrificed after 30 days of consolidation. Afterward, samples were prepared for histomorphometric evaluation of newly formed bone area. RESULTS The number of osteoblasts and blood vessels was significantly higher, whereas the number of osteoclasts was significantly lower, in the experimental group than in the control group (P < .05). In the experimental group, the area of new bone formation was greater than in the control group (P < .05). Moreover, fibroblast and collagen numbers per unit area were higher in the experimental group. However, this finding was not statistically significant (P > .05). CONCLUSION The subcutaneous administration of rHuEPO improves the rate and quality of bone-healing during distraction osteogenesis. However, the short-term favorable effects of rHuEPO in this study should be extended with long-term investigations before clinical application.

Treatment of localized Langerhans' cell histiocytosis of the mandible with intralesional steroid injection: report of a case.

Localized Langerhans cell histiocytosis (LLCH), formerly known as eosinophilic granuloma, mainly affects the skull, mandible, vertebrae, and ribs in children and the long bones of adults. Symptoms range from none to pain, swelling, and tenderness over the site of the lesion. General malaise and fever occasionally are present. Radiographically, lesions appear as radiolucent areas with well demarcated borders. LLCH may resolve spontaneously after biopsy in a period of months to years. However, if features include continuous pain, decrease of function, pathologic fractures, migration and resorption of teeth, or rapid progression, then active treatment needs to be considered. Treatment approaches include surgery, radiotherapy, chemotherapy, and intralesional injection of corticosteroids. In children with mandibular LLCH, 1 dose of methyprednisolone succinate injection has proven to be adequate. However, injections have not been performed in cases involving pathologic fracture. We report a new case of LLCH of the mandible that caused a pathologic fracture in an adult patient. Repeated intralesional corticosteroid injections resulted in fracture line disappearance within 14 months and lesion healing by the end of the 36-month follow-up.