Comparative radiologic analyses of newly formed bone after maxillary sinus augmentation with and without bone grafting.

PURPOSE: The present study examined the formation and density of new bone after sinus membrane elevation, with and without bone grafting, and evaluated the bone formation at the apices of the implants with these 2 different maxillary sinus floor elevation techniques. MATERIALS AND METHODS: In a prospective randomized controlled study design, patients requiring reconstruction of their atrophic maxilla were included and divided randomly into grafted and nongrafted groups. Implants were inserted in each group by way of sinus membrane elevation. The formation and density of new bone were evaluated using cone beam computed tomography, performed preoperatively and 1 week, 3 weeks, and 6 months postoperatively. RESULTS: A total of 24 implants were placed in 14 patients, with all implants maintaining stability during 6 months of follow-up. New bone formation was determined in both groups using radiography. No significant differences were found between the 2 groups in terms of new bone density preoperatively nor at 1 week or 3 months postoperatively. However, the density of bone in the nongrafted group was higher than that in the grafted group 6 months after surgery. CONCLUSIONS: These results suggest that the simple elevation of the sinus membrane without bone grafting material can lead to bone formation around implants and that the newly formed bone in the nongrafted group was denser than that in the grafted group.

A 3-year follow-up of the rehabilitation of Papillon-Lefèvre syndrome by dental implants.

PURPOSE: Papillon-Lefèvre syndrome is a rare autosomal recessive genetic disorder characterized by palmar-plantar hyperkeratosis, with rapidly progressive periodontitis and premature loss of both deciduous and permanent teeth. This article presents the prosthetic rehabilitation of a patient with Papillon-Lefèvre syndrome with dental implants. MATERIALS AND METHODS: Twelve titanium implants were installed in the mandible and maxilla in an 18-year-old male patient with Papillon-Lefèvre syndrome. RESULTS: At 3 years follow-up, all implants were clinically stable and no pain or infection was found. The patient continues to be seen at regular follow-up visits. CONCLUSION: Twelve-implant installation in Papillon-Lefèvre syndrome with 3 years' follow-up has not claimed before. We not only successfully treated our patient functionally and esthetically with dental implant rehabilitation, but also provided psychological benefits to the patient.

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.

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 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.

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.

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.

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.

Experimental evaluation of the effects of zoledronic acid on regenerate bone formation and osteoporosis in mandibular distraction osteogenesis.

PURPOSE: The aim of this study was to evaluate the effects of systemically administered zoledronic acid (ZA) on the bone mineral density (BMD) and bone mineral content (BMC) at mandibular distraction sites in rabbits. MATERIALS AND METHODS: Eighteen New Zealand white rabbits were randomly divided into 2 groups. Bone lengthening was performed in the left portion of the mandible through distraction osteogenesis at a rate of 0.5 mm every 12 hours for 5 days. While the experimental group rabbits were administered intravenous 0.1 mg/kg ZA, control group rabbits were given only saline infusion during operation. All animals were sacrificed at the end of the consolidation period of 28 days. The mandibles of all animals were removed and both the anterior and posterior pin regions of the regenerate and regenerate region were evaluated by dual energy x-ray absorptiometry (DEXA). BMD and BMC data were statistically analyzed. RESULTS: Except for 1 rabbit from the experimental group that had an infection at the external pin region, all animals showed complete clinical healing. When the values in the group receiving ZA were compared with those of the control group, it was observed that the BMD values of the anterior pin region of regenerate, regenerate region, and posterior pin region increased by 23%, 20%, and 31%, respectively; and BMC values increased by 22%, 24%, and 32%, respectively. When data of these regions were compared, both BMD and BMC were found statistically different in all regions (P < .05). CONCLUSION: Results of this study showed that ZA had positive effects on new bone formation at and around the distraction gaps of the lengthened rabbit mandibles by distraction osteogenesis.