Management of central giant cell granuloma of the jaws with intralesional steroid injection and review of the literature.

PURPOSE: We report the results of the intralesional steroid injections for the management of central giant cell granuloma (CGCG) of the jaws. METHODS: Seven CGCGs were treated with intralesional injection of corticosteroids. To accomplish this, 3.5 mL of triamcinolone and 3.5 mL of 0.5 % marcaine with 1/200,000 epinephrine (total 7 mL) were mixed. An adequate amount of steroid was injected into different areas of the lesion. This procedure was repeated on a weekly basis for 6 weeks. RESULTS: Clinical and radiological examination showed complete resolution and ossification of the lesions in four patients. Partial recovery was achieved in two patients. One patient did not respond to the treatment and underwent surgical curettage. CONCLUSIONS: We suggest that intralesional steroid injection is safe and effective for the treatment of CGCG, especially in non-aggressive lesions.

The relationship between changes in the expression of growth associated protein-43 and functional recovery of the injured inferior alveolar nerve following transection without repair in adult rats.

OBJECTIVE: The objective of this study was to analyze the changes in the expression of growth associated protein-43 (GAP-43) in trigeminal ganglions (TGs) and in the distal stumps of transected inferior alveolar nerves (IANs), and to clarify the relationship between these changes and functional recovery of the transected IAN without repair using a rat IAN axotomy model. MATERIAL AND METHODS: Following transection, GAP-43 expression was measured at multiple time points. The functional recovery of the transected IAN was evaluated based on the compound muscle action potentials recorded from the digastric muscle. RESULTS: GAP-43 expression in TGs was significantly higher at 2, 7, 14, 28, and 56 days following IAN transection compared to that in samples from sham-operated rats (p < 0.0005, p < 0.0005, p < 0.0005, p = 0.007, and p = 0.023, respectively). GAP-43 expression in the distal stumps of transected IANs was significantly higher at 2, 7, 14, and 28 days following IAN transection compared to that in samples taken from sham rats (p < 0.0005, p < 0.0005, p < 0.0005, and p = 0.009, respectively). GAP-43 expression in the distal stumps of transected IANs returned nearly to sham levels by day 56 following IAN transection. On days 7, 14, 28, and 56 following transection, the amplitude of the compound muscle action potential gradually increased, the latency gradually decreased, and the duration gradually increased. The amplitude, latency, and duration of the compound muscle action potentials nearly returned to sham levels on post-transection day 56. CONCLUSIONS: Time-dependent changes in the expression of GAP-43 in both TGs and distal stumps of transected IANs without repair are synchronously consistent with the regeneration and functional recovery of the transected IAN. The recovery of the amplitude, latency, and duration of the compound muscle action potentials indicates increased myelination and increased axon density of the regenerated nerve fibers.

Effects of different biomaterials on augmented bone volume resorptions.

OBJECTIVES: The aim of this study was to assess the effects of platelet-rich fibrin (PRF), deproteinized bovine bone graft (DBBG), and biphasic calcium phosphate (BCP) biomaterials on total volume resorption levels and bone augmentation. MATERIALS AND METHODS: Nine New Zealand rabbits were divided into three groups (PRF, DBBG, and BCP). Two titanium barriers were fixed bilaterally to each rabbit's calvarium; a total of 18 titanium barriers were used. All barriers were removed on the 90th day. Computed tomography (CT) images of the animals were taken on the 90th, 120th, 150th, and 180th days. RESULTS: When the resorption level of the total volume in all groups on the 120th, 150th, and 180th days was compared with that of the 90th day, no significant differences among all groups were found in all intervals. According to the total volume on the 90th and 180th days, statistically significant differences between groups DBBG and BCP were not found; however, statistically significant differences were found between group PRF and the others groups (P < 0.001). On the other hand, there were statistically significant differences in regenerated bone area between group PRF and BCP. CONCLUSION: According to the results of this study, grafts such as DBBG or BCP must be used to augment bone volume sufficiently in guided bone regeneration.

The effect of local simvastatin application on critical size defects in the diabetic rats.

OBJECTIVES: To evaluate bone-healing effects of local simvastatin application to critical size defects (CSDs) in the experimental diabetes mellitus (DM) rat model. MATERIALS AND METHODS: A total of 35 male Sprague-Dawley rats with an average weight of 350 g and aged 3 months were used in this study. The rats were divided into five groups of seven animals each: passive control (group A), active control (group B), 0.5 mg simvastatin (group C), 1.0 mg simvastatin (group D), and 1.5 mg simvastatin (group E). Streptozotocin was used to induce Type 1 diabetes in all rats. Eight mm CSDs were created under anesthesia in each rat calvarium. CSDs were left empty in group A. Defects in group B were grafted alone with a gelatin sponge mixed with normal saline. Defects in the experimental groups (groups A, B, and C) were grafted with gelatin sponge mixed saline solutions contain 0.5, 1.0, 1.5 mg simvastatin. Rats were sacrificed after 1 month, and the defects were prepared for radiologic and histomorphometric assessment of regenerated bone. RESULTS: None of the specimens exhibited complete closure of new bone across the 8-mm defect. A correlation between computed tomography and histomorphometric analysis was not determined. Both amount of volume and area of regenerated bone were found higher in the experimental groups than in the control groups. However, these values were not found statistically significant degree (P < 0.05) for each groups. The density of regenerated bone in the region of interest was higher in the control groups in contrast to in the experimental groups. However, statistical significance was just found between groups C and A and between groups C and B (P < 0.05). CONCLUSION: The local simvastatin application enhanced healing of the bone defects in the diabetic rat model CSDs.

Comparison of a novel trephine drill with conventional rotary instruments for maxillary sinus floor elevation.

PURPOSE: The purpose of this study was to compare a newly designed trephine drill (SLA KIT, Neobiotech) with conventional rotary instruments for maxillary sinus floor elevation based on operative time, postoperative pain, and perforation rates. MATERIALS AND METHODS: Twenty-five patients were treated with a bilateral sinus floor elevation procedure with rotary trephine and conventional instruments. One side was treated with conventional rotary instruments, while the contralateral side was treated with rotary trephine instruments, with a 2-week gap between surgeries. Operative time was measured with a chronometer in seconds as the time from soft tissue incision to primary closure of the incision with the last suture. Pain was scored on a 10-point visual analog scale at 24 hours after surgery. The presence of tears and perforations was determined by direct visualization and the Valsalva maneuver. RESULTS: Twenty-five patients were included in the study. Operative time was shorter when the trephine drill was used (11.1 ± 2.4 minutes) than with conventional rotary instruments (15.1 ± 2.9 minutes). Sinus membrane perforation was observed in eight patients when conventional rotary instruments were used, while the trephine drill resulted in two sinus perforations. Mean pain scores were 2.01 ± 0.11 after using the trephine drill and 2.25 ± 0.76 when conventional rotary instruments were used. No significant difference was found in postoperative pain scores. CONCLUSION: The trephine drill technique may result in decreased perforation rates and operative time.

Effects of platelet rich fibrin alone used with rigid titanium barrier.

OBJECTIVE: Platelet-rich fibrin (PRF) is a platelet and leukocyte rich and platelet preparation that concentrates various growth factors and therefore has the potential to be used as regenerative treatment. The aim of study was to assess the effects of platelet rich fibrin (PRF) on bone augmentation when used in conjunction with titanium barrier a rabbit calvaria model. STUDY DESIGN: Twenty-four adult male New Zealand rabbits were used in this study. Two titanium barriers were fixed on each rabbit's calvarium. The rabbits were divided into four groups (group one is control and the other three groups are experimental) and each group contains 6 animals. PRF, anorganic bovine bone (ABB), and biphasic calcium phosphate (BCP) were used with titanium barriers in the experimental groups. Any materials were not used in the control group. Half of the animals were sacrificed after 1 month, and the rest were sacrificed after 3 months. Histomorphometric evaluation was carried out in order to compare new bone formation among the groups. RESULTS: Significantly more new bone area was noted in the PRF alone group than in the control group, no statistically significant differences were found among PRF, BCP and ABB groups after 1 month. PRF and ABB also had superior effects in new bone formation area control to the BCP group after 3 months. CONCLUSION: PRF may offer the ease of use, simple handling, and enhanced delivery of growth factors during the bone augmentation procedures. When used in conjunction with the titanium barriers, PRF use can increase the quality of the newly formed bone and enhance the rate of bone formation due to the concentration of growth factors.

Distracted mandible does not reach the same strength as normal mandible in rabbits.

OBJECTIVE: The aim of this study was to determine the resistance and fracture strength values of the bone with the use of biomechanical tests in different consolidation periods of mandibular distraction osteogenesis. STUDY DESIGN: In this study, 21 mature male New Zeland rabbits were used. After distraction, rabbits were separated into 3 groups to experience 4, 8, and 12 weeks' consolidation periods. Nonoperated hemimandibles of 6 rabbits were used as a control group. After 5 days' latency period, 0.5-mm distraction was applied twice a day, i.e., 1 mm/d lengthening. After the 5-mm lengthening application, we left the animals for 1, 2, or 3 months of consolidation period. Bending stress and strength values of the bone at fracture point were measured with the use of a 3-point bending test. RESULTS: There were significant differences between the control and 3 study groups regarding bending stress and strength values. In addition, each study group was significantly different from each other. CONCLUSIONS: Bending stress and fracture strength of the bone may not reach that of normal bone after completion of 3 months' consolidation. It should be considered to keep in place extraoral appliances or comfortable intraoral distractors for a long period.

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.

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.

Pathologic changes in soft tissues associated with asymptomatic impacted third molars.

OBJECTIVE: The aim of this study was to examine the need for routine removal of asymptomatic impacted third molars under the prophylactic indication, based on the incidence of pathologic changes. The frequency and type of pathologic conditions associated with impacted third molars were also evaluated. STUDY DESIGN: One hundred twenty impacted third molar dental follicles were submitted for histopathologic examination. The association between dental follicles and pathologic changes, age, gender, and angular position were statistically evaluated. RESULTS: Among these dental follicles, pathologic conditions were found in 23%. The relation between pathologic changes and angular position was not statistically significant (chi(2) = 2.040; P > .05). Pathologic changes were seen mostly in women who were > or = 20 years old. CONCLUSIONS: Cystic changes may be developed in asymptomatic impacted third molars. Asymptomatic impacted third molars should be removed before pathologic changes can occur.