Histopathological Examination of the Effects of Local and Systemic Bisphosphonate Usage in Bone Graft Applications on Bone Healing.

BACKGROUND: The effect of bisphosphonates on the resorption process of normal bone tissue has been clearly mentioned in the literature, while their effect on the grafting material is a new research area. Limited former study is not sufficient to determine the strength, reliability and dosage of bisphosphonates. In this study, our aim is to examine the effects of local and systemic use of bisphosphonates in bone graft applications on bone healing, histopathologically. METHODS: Therefore, 32 Sprague-Dawley rats are separated into four groups. In the first group, only an empty bone defect is made on tibia and the tissue is sutured primarily without any other application. In the second group, bone defect is filled with allograft material and closed without any other application. In the third group (LA), alendronate solution is locally added to the graft material before its application to the site of bone defect. In the fourth group, alendronate is applied systemically after the site of bone defect is grafted and primarily closed. After 6 weeks, all rats are killed and the obtained samples are examined histopathologically. RESULTS: Local and systemic application of alendronate increases new bone formation in a statistically significant degree. In LA group, newly formed bone was observed more mature and well developed. Alendronate application does not cause an increase in inflammation, fibrosis and necrosis. There is no increased necrosis with alendronate application. CONCLUSION: Local and systemic application of alendronate in bone grafting increases bone formation without any other complication. But we believe that further research should be made on dosage, usage and possible side effects.

Prosthetically driven immediate implant placement at lower molar area; an anatomical study.

PURPOSE: To examine the effectiveness and safety of immediate implant placement (IIP), we evaluated the risk of lingual plate perforation (LPP) and mandibular canal perforation (MCP) associated with posterior mandible anatomy using cone beam computed tomography (CBCT) images. MATERIALS AND METHODS: A morphological study of the molar sockets of 135 patients (age: 18-84 y) was done and its relationship to the mandibular canal was investigated. The risk of LPP and MCP was recorded as yes or no. Mandibular cross-sectional morphology was defined as one of three types (U-P-C) using the criteria of Chan et al. RESULTS: The risk of LPP was significantly higher for second molars (p = 0.0001), and the risk increased with age (p = 0.039). There was a strong relationship between the risk of LPP and cross-section type U (p = 0.0001). The mean root to alveolar canal (RAC) distance (mm) of males was significantly higher than that of females. The mean RAC value was 5.02 mm for males and 3.49 mm for females. There was no statistically significant relationship between the risk of MCP and sex. There was a significant relationship between the risk of MCP and cross-section type U (p = 0.0001). Although the MCP risk was higher in second molars, there was no statistically meaningful relation between MCP and tooth type. CONCLUSION: The results suggest that IIP in the mandibular molar area carries a high risk of MCP and LPP. Based on the elevated level of risk, a delayed implant protocol should be considered.

Orthognathic Surgery after Mandibular Large-Volume Osteoma Treatment.

Osteoma is a benign asymptomatic osseous tumor. Characterization of osteoma is the proliferation of cancellous or compact bone that increases in size by continuous formation of bone. It can be seen in any craniofacial structures, usually in paranasal sinuses and jaws. In this study, we present a 17-year-old male patient with a giant osteoma in the mandibular condyle. Posttreatment post-op follow-up, post-ortho, and orthognathic surgery after dental implantation are described.

Fixation Methods for Mandibular Advancement and Their Effects on Temporomandibular Joint: A Finite Element Analysis Study.

OBJECTIVES: Bilateral sagittal split osteotomy (BSSO) is a common surgical procedure to correct dentofacial deformities that involve the mandible. Usually bicortical bone fixation screw or miniplates with monocortical bone fixation screw were used to gain stability after BSSO. On the other hand, the use of resorbable screw materials had been reported. In this study, our aim is to determine first stress distribution values at the temporomandibular joint (TMJ) and second displacement amounts of each mandibular bone segment. METHODS: A three-dimensional virtual mesh model of the mandible was constructed. Then, BSSO with 9 mm advancement was simulated using the finite element model (FEM). Fixation between each mandibular segment was also virtually performed using seven different combinations of fixation materials, as follows: miniplate only (M), miniplate and a titanium bicortical bone fixation screw (H), miniplate and a resorbable bicortical bone fixation screw (HR), 3 L-shaped titanium bicortical bone fixation screws (L), 3 L-shaped resorbable bicortical bone fixation screws (LR), 3 inverted L-shaped titanium bicortical bone fixation screws (IL), and 3 inverted L-shaped resorbable bicortical bone fixation screws (ILR). RESULTS: At 9 mm advancement, the biggest stress values at the anterior area TMJ was seen at M fixation and LR fixation at posterior TMJ. The minimum stress values on anterior TMJ were seen at L fixation and M fixation at posterior TMJ. Minimum displacement was seen in IL method. It was followed by L, H, HR, M, ILR, and LR, respectively. CONCLUSION: According to our results, bicortical screw fixation was associated with more stress on the condyle. In terms of total stress value, especially LR and ILR lead to higher amounts.

In Vitro Evaluation of Manual Torque Values Applied to Implant-Abutment Complex by Different Clinicians and Abutment Screw Loosening.

Preload is applied to screws manually or using a torque wrench in dental implant systems, and the preload applied must be appropriate for the purpose. The aim of this study was to assess screw loosening and bending/torsional moments applied by clinicians of various specialties following application of manual tightening torque to combinations of implants and abutments. Ten-millimeter implants of 3.7 and 4.1 mm diameters and standard or solid abutments were used. Each group contained five implant-abutment combinations. The control and experimental groups comprised 20 and 160 specimens, respectively. Implants in the experimental group were tightened by dentists of different specialties. Torsional and bending moments during tightening were measured using a strain gauge. Control group and implants with preload values close to the ideal preload were subjected to a dynamic loading test at 150 N, 15 Hz, and 85,000 cycles. The implants that deformed in this test were examined using an optical microscope to assess deformities. Manual tightening did not yield the manufacturer-recommended preload values. Dynamic loading testing suggested early screw loosening/fracture in samples with insufficient preload.

Is immediate implant placement possible in the maxillary molar area? An anatomical study.

The dimensions of maxillary first molars were investigated and measured using cone beam computed tomography (CBCT) to examine the effectiveness of immediate placement of implants in the maxillary molar area. The CBCT images of 68 patients were collected. The dimensions of the maxillary first molar sockets were measured in both sagittal and coronal aspects, as well as the height of the alveolar bone crest (ABC) to the sinus membrane (SM) at optimal implant position. Sinus membrane and maxillary first molar relationships were analyzed sagittally and coronally. Interradicular bone presence and root intrusion into the sinus (IRS) were also noted. No statistically significant relationship was observed between IRS and age or sex. However, IRS was significantly related to sagittal type, as a type 1 sagittal relationship was characterized by greater root intrusion. The socket dimensions of male subjects were statistically significantly greater than those of female subjects, both coronally and sagittally. Changes in the socket dimensions were not significantly related to age in the sagittal plane. However, coronal plane measurements did increase with age. ABC-SM measurements decreased with age, but these changes were not statistically significant. These results showed that the socket dimensions in the maxillary first molar area are adequate for wider implant placement, but an implant longer than 8 mm increased the risk of perforation. All oral surgeons should be familiar with these anatomical variations so they can adopt appropriate additional practices and inform patients about the risks before operating.

Dental Cone Beam Computed Tomography Analyses of the Anterior Maxillary Bone Thickness for Immediate Implant Placement.

OBJECTIVE: We evaluated the thickness of the facial alveolar bone wall at the maxillary incisors based on cone beam computed tomography (CBCT) images. MATERIALS AND METHODS: The CBCT images of 60 patients were collected. We measured the distance between the cemento-enamel junction to alveolar bone crest (CEJ-ABC) and the facial alveolar bone width at levels 1 (P1), 2 (P2) and 5 (P3) mm apical to the bone crest. RESULTS: The P2 and P3 scores had a statistically significant negative relationship with age, and the CEJ-ABC scores had a statistically significant positive relationship with age for all samples. Regarding the CEJ-ABC scores, there were no statistically significant differences between genders. However, the P1 values of tooth 11 and 21 were statistically significantly greater for female patients, and the P2 value of tooth 22 was statistically significantly greater for male patients. CONCLUSION: The bone in the anterior maxillary area is very thin, only rarely meeting the minimum of 2 mm necessary for optimal aesthetic and functional results. Thus, for most patients, adjunctive augmentation procedures may be needed for implant treatment.

Immediate implants after enucleation of an odontogenic keratocyst: an early return to function.

An odontogenic keratocyst is a unique cyst because of its locally aggressive behavior, high recurrence rate, and characteristic histologic appearance. In this article we present the case of a 22-year-old male patient with a large odontogenic keratocyst and describe his treatment with immediate dental implants.

Use of cone-beam computerized tomography for evaluation of bisphosphonate-associated osteonecrosis of the jaws in an experimental rat model.

BACKGROUND: Bisphosphonate-induced osteonecrosis of the jaw (BONJ) is a frequently reported complication. The aim of this study was to investigate the clinical and histopathological presentation of BONJ with the Hounsfield score and to evaluate the reliability of the score for determining necrosis in an animal model. MATERIAL/METHODS: Eighty rats were prospectively and randomly divided into two groups of 40 each: a control group and an experimental group. Half of the animals from each group underwent extraction of the left mandibular molars, and the other half underwent extraction of the left maxillary molars under pentobarbital-induced general anesthesia. All animals were euthanized 28 days after tooth extraction. Maxillae and mandibles were extracted, cone beam computed tomography (CBCT) was performed, and Hounsfield scores were evaluated. RESULTS: The Hounsfield scores of the experimental group were found to be compatible with chronic osteomyelitis and periosteal reactions. The Hounsfield scores of the control group were compatible with a healthy healing period. CONCLUSION: In light of these results, both cone beam computed tomography (CBCT) and the Hounsfield Units (HU) evaluations together are thought to be efficient in the diagnosis of BONJ.

Extraction socket healing in rats treated with bisphosphonate: Animal model for bisphosphonate related osteonecrosis of jaws in multiple myeloma patients

Aim: The aim of this study is to replicate both clinical and histological presentation of bisphosphonate inducedosteonecrosis of the jaws (BONJ) in an animal model of the disease state. Successful recapitulation of a BONJlikeindication in an animal model will be useful for studying pathogenesis, as well as prevention and treatment strategies for BONJ.Materials and Methods: Eighty (80) rats were prospectively and randomly divided into two groups; control group(40)and study group(40). All animals in study group, injected with a dose of 1 mg/kg dexamethasone (DX) subcutaneouslyon day 7, 14, or 21; and 1, 2, or 3 doses of 7.5 ìg/kg zoledronic acid (ZA) subcutaneously administered to coincide with the last day of DX. Half of the animals from each group under went extraction of the left mandibular molars and the remaining animals under went extraction of the left maxillary molars under pentobarbital-induced general anesthesia. All animals were euthanized twenty-eight (28) days following tooth extractions.Results: The amount of new bone trabecules as significantly decreased in bisphosphonate-dexamethasone (BPDX)treated sockets. Difference between both groups was found statistically significant (p=0,0001). There’s noforeign body reaction in sockets of both groups and no significance difference observed for fibrosis (p=0,306).The necrosis scores were significantly higher in BP-DX treated sockets (p=0,015). The inflamation scores were significantly higher for study group (p=0,0001).Conclusion: This study provides preliminary observations for the development of an animal model of BONJ. But we think that there is need for other studies have only BP treated group and larger study population (AU)

Extraction socket healing in rats treated with bisphosphonate: animal model for bisphosphonate related osteonecrosis of jaws in multiple myeloma patients.

AIM: The aim of this study is to replicate both clinical and histological presentation of bisphosphonate induced osteonecrosis of the jaws (BONJ) in an animal model of the disease state. Successful recapitulation of a BONJ-like indication in an animal model will be useful for studying pathogenesis, as well as prevention and treatment strategies for BONJ. MATERIALS AND METHODS: Eighty (80) rats were prospectively and randomly divided into two groups; control group(40) and study group(40). All animals in study group, injected with a dose of 1 mg/kg dexamethasone (DX) subcutaneously on day 7, 14, or 21; and 1, 2, or 3 doses of 7.5 µg/kg zoledronic acid (ZA) subcutaneously administered to coincide with the last day of DX. Half of the animals from each group underwent extraction of the left mandibular molars and the remaining animals underwent extraction of the left maxillary molars under pentobarbital-induced general anesthesia. All animals were euthanized twenty-eight (28) days following tooth extractions. RESULTS: The amount of new bone trabecules as significantly decreased in bisphosphonate-dexamethasone (BP-DX) treated sockets. Difference between both groups was found statistically significant (p=0,0001). There's no foreign body reaction in sockets of both groups and no significance difference observed for fibrosis (p=0,306). The necrosis scores were significantly higher in BP-DX treated sockets (p=0,015). The inflamation scores were significantly higher for study group (p=0,0001). CONCLUSION: This study provides preliminary observations for the development of an animal model of BONJ. But we think that there is need for other studies have only BP treated group and larger study population.

Effects of folk medicinal plant extract Ankaferd Blood Stopper on early bone healing.

OBJECTIVE: Several haemostatic agents are available for clinical use. Ankaferd Blood Stopper (ABS), a mixture of five medicinal plant extracts, has been used historically as a haemostatic agent. The aim of this in vivo study was to investigate the effects of ABS on early bone healing using a rat tibia defect model. MATERIAL AND METHODS: Sixteen male Wistar rats were randomized into two groups of 8 animals each. After deep anesthesia with ketamine, bone defects (3 mm diameter and 2 mm deep) were created in the right and left tibiae of all animals and either treated with 1 cc of ABS (Group 1) or left untreated (Group 2; control). Surgical areas were closed primarily. The animals were sacrificed on the 7th postoperative day and bone samples were collected from the tibias. The samples were examined histopathologically for infection, necrosis, fibrosis, new bone formation and foreign body reaction. The histomorphometric results were analyzed statistically by the chi square test, with the level of significance set at p<0.05. RESULTS: Significant differences were found in both groups in terms of inflammation, necrosis and new bone formation (p=0.001, p=0.0001, p=0.001). No foreign body reaction was observed in the experimental group. ABS application decreased fibrosis in the experimental group, but there were no statistically significant differences from the control group. CONCLUSIONS: Histopathologically, it was observed that the application of ABS decreased the occurrence of inflammation and necrosis, while increasing new bone formation in early bone healing period. Further in vitro and in vivo studies are necessary for evaluating the benefits and possible adverse effects of the application of this herbal product on wound healing.

Effects of folk medicinal plant extract Ankaferd Blood Stopper® on early bone healing

OBJECTIVE: Several haemostatic agents are available for clinical use. Ankaferd Blood Stopper® (ABS), a mixture of five medicinal plant extracts, has been used historically as a haemostatic agent. The aim of this in vivo study was to investigate the effects of ABS on early bone healing using a rat tibia defect model. MATERIAL AND METHODS: Sixteen male Wistar rats were randomized into two groups of 8 animals each. After deep anesthesia with ketamine, bone defects (3 mm diameter and 2 mm deep) were created in the right and left tibiae of all animals and either treated with 1 cc of ABS (Group 1) or left untreated (Group 2; control). Surgical areas were closed primarily. The animals were sacrificed on the 7th postoperative day and bone samples were collected from the tibias. The samples were examined histopathologically for infection, necrosis, fibrosis, new bone formation and foreign body reaction. The histomorphometric results were analyzed statistically by the chi square test, with the level of significance set at p<0.05. RESULTS: Significant differences were found in both groups in terms of inflammation, necrosis and new bone formation (p=0.001, p=0.0001, p=0.001). No foreign body reaction was observed in the experimental group. ABS application decreased fibrosis in the experimental group, but there were no statistically significant differences from the control group. CONCLUSIONS: Histopathologically, it was observed that the application of ABS decreased the occurrence of inflammation and necrosis, while increasing new bone formation in early bone healing period. Further in vitro and in vivo studies are necessary for evaluating the benefits and possible adverse effects of the application of this herbal product on wound healing.

Radiologic evaluation of an unusually sized complex odontoma involving the maxillary sinus by cone beam computed tomography.

As a group, odontomas are the most common odontogenic neoplasms. This case report illustrates the benefits of cone beam computed tomography, in terms of treatment planning and surgical technique, to localize a large maxillary odontoma and accurately establish its relationship with the maxillary sinus and molar.