A. Alper Pampu

Jaw bone changes in rats after treatment with zoledronate and pamidronate

OBJECTIVE The aim of this study was to histopathologically evaluate the effects of pamidronate and zoledronate on the mandible in an animal model. STUDY DESIGN Sixty female Sprague-Dawley rats were used in this study. Animals were divided into 6 groups (10 per group): control-1 (C1), injected with saline solution for 6 weeks; zoledronate-1 (ZA1), injected with zoledronate for 6 weeks; pamidronate-1 (PA1), injected with pamidronate for 6 weeks; control-2 (C2), injected with saline solution for 8 weeks; zoledronate-2 (ZA2), injected with zoledronate for 8 weeks; and pamidronate-2 (PA2), injected with pamidronate for 8 weeks. No dental procedures were performed on the animals. Rats were killed 2 days after the end of drug therapy, and the posterior and anterior mandible and femur of each rat were evaluated histopathologically. RESULTS Histological examination revealed inflammation limited to the posterior mandible of the ZA2 and PA2 groups; the anterior mandible and femur were not affected. Soft tissue necrosis was evident in one rat in the ZA2 group. CONCLUSION Specific, bisphosphonate-associated inflammatory bony and soft tissue changes were observed in the mandible, suggesting that these drugs may set the stage for altered healing associated with the development of bisphosphonate-related osteonecrosis of the jaw.

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.

Marsupialization of unicystic ameloblastoma: A conservative approach for aggressive odontogenic tumors

Unicystic ameloblastoma (UA) is known as a distinct entity which has a less aggressive behavior when compared with conventional ameloblastoma. In this report, we have presented two cases of UAs, (of which one case showed a more aggressive behavior with mural invasion into the adjacent tissues and granular cell differentiation), both of which were successfully managed with enucleation following marsupialization. We aim to highlight how this method can be used for the successful management of such cases, rather than following more aggressive approaches. In both the cases, marsupialization was done for the UA lesions initially and follow-ups were maintained. When the tumor size had regressed on radiographic follow up, an enucleation procedure with ostectomy of the margins was carried out. Special importance was also given to the endodontic treatment of the teeth involved in the area of the lesion. The patients were free of the condition and did not show any signs of recurrence on radiographic follow-ups even after 30 months of the final procedure. Granular variant of UA is quite rare and had been considered to be more aggressive. Marsupialization of UA is an alternative treatment option of resection even for more aggressive variants, as long as the histological behavior of the lesion was carefully evaluated and strict radiographic follow-up is maintained.

Orthodontic Treatment of an Ankylosed Maxillary Central Incisor through Osteogenic Distraction

Tooth ankylosis is one of the various problems in dentistry and requires special treatment approaches for satisfactory results. In the orthodontic treatment of an ankylosed tooth, different treatment modalities have been put into practice including both orthodontic and orthodontic-surgical approaches. For favorable results, gingival margin esthetics must be considered as much as leveling the ankylosed tooth in the arch. Distraction osteogenesis accompanied by orthodontic mechanics is a sensible way of achieving this goal. However, devices used in the distraction protocol are high in price and bulky in shape, causing functional and esthetic problems for the patient. This report describes treatment of an infrapositioned ankylosed incisor with continuous distraction forces produced by conventional orthodontic mechanics. In conclusion, the ankylosed tooth was leveled in the upper arch successfully with a harmonic gingival margin.

Evaluation of sedation in oral and maxillofacial surgery in ambulatory patients: failure and complications

OBJECTIVES This study evaluated the failure and complication rates of sedation in ambulatory patients undergoing oral and maxillofacial surgery. MATERIALS AND METHODS This retrospective cohort study was carried out among 619 patients who had undergone maxillofacial surgical procedures under intravenous sedation with midazolam and fentanyl. Each patients age, American Society of Anesthesiologists (ASA) classification, systemic condition, surgical procedure, complications, and failures were recorded for evaluation. RESULTS A total of 400 patients with ASA I, 199 with ASA II, and 20 with ASA III between the ages of 9 months and 84 years were included in the study. The most common systemic disorders in our patients were mental retardation (35%), hypertension (19%), and epilepsy (15%). Evaluation of the cases revealed 9 complications (1.4%) and 9 sedation failures (1.4%). The complications were bradycardia, postoperative agitation and hallucination, drug reaction, vomiting and nausea, desaturation, and hypotension. CONCLUSIONS Our results in the oral and maxillofacial surgery clinic revealed low complication and failure rates.

Histomorphometric evaluation of delayed changes in masseter muscle after lengthening the rabbit mandible by distraction osteogenesis.

OBJECTIVE The aim of the study was to evaluate the delayed responses and changes of gradually lengthened masseter muscles of rabbit mandibles. STUDY DESIGN Unilateral lengthening of rabbit mandibles was performed in 18 New Zealand rabbits for 7 days at the rate of 1 mm day(-1). Mandibles of animals were removed at months 3, 4, and 6 after distraction. Biopsy samples of distracted and contralateral side masseter muscles were histopathologically evaluated and mean area of muscle fibers (MAF) was evaluated with histomorphometric methods. Results were statistically analyzed. RESULTS Mild to moderate atrophy of the fibers, and necrosis and myophagocytosis in some areas were the leading features at month 3 and which were decreased at month 4 in distracted side-muscle specimens, with no statistically significant differences when compared with non-distracted side muscles at the same periods. Almost completely, normal fibers were detected in distracted muscle specimens at month 6. Evidence of myopathic changes was found to disappear at month 6 and no significant difference was found in the MAF of distracted side muscles. CONCLUSION This study showed that the masseter muscle could adapt to gradual lengthening of the mandible within 6 months. Regenerative features and some degree of atrophic changes that could be observed at months 3 and 4 disappeared at month 6, with adaptation of the fibers.

Histomorphometric examination of long-term changes in temporomandibular joints after mandibular lengthening by distraction osteogenesis in rabbits

OBJECTIVE The purpose of this study was to evaluate long-term histomorphometric changes in temporomandibular joints (TMJs) of rabbits after mandibular distraction osteogenesis (DO). STUDY DESIGN Twenty-six rabbits were used in this study. Two of them served as control subjects, and the remaining 24 underwent DO procedures in their left mandibular bodies. After a latency period of 5 days, 5 mm lengthening was performed at a rate of 1 mm/d. The rabbits in the experimental group were randomly divided into 4 subgroups and killed after 1, 2, 4, and 6 months. TMJs from both sides were harvested and prepared with hematoxylin and eosin stain for histomorphometric examination under an optical microscope. RESULTS Compared with control subjects and nondistracted sides, fibrous articular, proliferative, and hypertrophic areas were significantly increased (P < .05) in the first 2 months in distracted sides. The changes were insignificant in the fourth and sixth postoperative months. CONCLUSION Unilateral mandibular distraction of 5 mm was found to be well tolerated and no degenerative changes were observed histologically in the rabbit TMJs in the long-term period.

The effects of osteoformin on mineralisation and quality of newly formed bone during mandibular distraction osteogenesis in rabbits

OBJECTIVE The aim of this experimental study was to evaluate the effects of osteoformin on mineralization and quality of newly formed bone during distraction osteogenesis in rabbits. STUDY DESIGN Distraction rate was as 1 mm/day for 5 days. In the experimental group, 100 microg/kg osteoformin in 100 microL/kg phosphate-buffered saline (PBS) was injected into the distraction area at day 1 and day 7 after surgery. In the control group, only 100 microL/kg PBS was injected on the same days. On day 42, the animals were killed. RESULTS Bone mineral density and bone mineral content values increased significantly in the experimental group (P < .05). Newly formed bone areas, number of vessels and osteoblasts were significantly greater in experimental group (P < .05). The number of fibroblasts were also greater, but it was not significant statistically (P > .05). The number of osteoclasts was significantly lower in experimental group (P < .05). CONCLUSION The results of this study show that osteoformin improves healing of regenerate in distraction osteogenesis in rabbits.

Comparison of the effects of new folkloric hemostatic agent on peripheral nerve function: an electrophysiologic study in rats

OBJECTIVE The aim was to evaluate the effects of a new folkloric medicinal plant extract on peripheral nerve function compared with oxidized regenerated cellulose (OC) and bovine collagen (BC). STUDY DESIGN Under ketamine anesthesia a total of 40 male Sprague-Dawley rat right sciatic nerves were identified. Animals were randomly divided into 5 groups: OC, BC, ankaferd blood stopper (ABS), and negative and positive control groups. The recordings of nerve potentials were carried out using an electrophysiologic data acquisition system. After the application of substances, the nerve conduction velocity (NCV) was recorded for immediate (30 min), early (120 min), and delayed (3 wk) effects on nerve function. RESULTS Statistically, differences were not found among the hemostatic agents (OC, BC, and ABS) at baseline and all tested periods (early, immediate, and delayed; P > .05). The positive control group exhibited lower NCV values compared with the other solutions at the 30-minute period (P < .05) as well as the other tested time periods (P > .05). OC exhibited NCV values closer to the positive control group at 120 minutes (P > .05). CONCLUSIONS Folkloric medicinal hemostatic agent could be considered as an acceptable hemostatic material without resulting in any serious peripheral nerve function alterations. The possible desirable effects of bovine collagen and undesirable effects of oxidized cellulose on peripheral nerve function should not be overlooked.