Effect of Autogenous Dentin Graft on New Bone Formation.

ABSTRACT: The aim of this study is to analyze the effects of autogenous dentin graft and mixture of autogenous dentin graft and platelet-rich fibrin (PRF) applied to the tooth extraction sockets on bone healing process. A total of 57 extraction sockets in 9 patients who were planned to be treated with dental implant after tooth extraction were evaluated in this study. Extraction sockets were divided randomly into 3 groups for each patient. In the first group, sockets were filled with autogenous dentin graft (Group D). In the second group, sockets were filled with the mixture of PRF and autogenous dentin graft (Group DP). In the third group, sockets were left empty as the control group (Group C). After 3 months, histological and immunohistochemical evaluations were performed on the samples taken during the implant surgery. Additionally, samples obtained from each group were examined by scanning electron microscopy. According to the histopathological findings, when the groups were compared in terms of new bone formation there was a significant difference between Group DP, both Group C, and Group D (P = 0.00), (P = 0.001). These findings supported by immunohistochemical results that showing increased bone morphogenetic protein-2 and Runt-related transcription factor-2 expression in Group DP. It has been concluded that undemineralized autogenous dentin graft has bone formation capacity on early period of bone healing. It can be used as bone graft material in augmentation procedures and its combined use with PRF accelerates new bone formation.

Stereological and histopathological evaluation of the effect of Thymoquinone on peridural fibrosis following laminectomy in rats

Background/aim: This study's aim was to investigate the effects of thymoquinone, which is the essential bioactive component of the volatile oil of Nigella sativa on the peridural fibrosis in rats following laminectomy. Materials and methods: Twenty female Wistar Albino rats were used in our study. The rats were randomly divided into 2 groups: Sham and Surgery + Thymoquinone. Both groups underwent laminectomy at L1 under general anesthesia. The Sham group was not subjected to any drug application. The 2nd group was treated with intraperitoneal 10-mg/kg thymoquinone once per day for a period of 28 days, following the same surgical procedure. All of the group specimens were sacrificed after 4 weeks, and the laminectomy area was examined in terms of new bone volume, capillary volume, and fibrosis volume using stereological approaches. Results: Statistically significant differences were found between the Sham and Surgery + Thymoquinone groups in terms of new bone volume (P = 0.01), capillary volume (P = 0.01), and fibrosis volume (P < 0.001). It was noted that Thymoquinone caused a significant increase in new bone volume, vascular volume and, a significant decrease in fibrosis volume. Conclusion: The results of our study indicate that thymoquinone is effective in decreasing peridural fibrosis when applied to a laminectomy model.

Extracorporeal Shock-Wave Therapy or Low-Level Laser Therapy: Which is More Effective in Bone Healing in Bisphosphonate Treatment?

OBJECTIVES: Bisphosphonate-related osteonecrosis of the jaw is potential side effect of long-term bisphosphonate therapy. Different treatment modalities have been used in this and investigate the effects of low-level laser therapy (LLLT) and extracorporeal shockwave therapy (ESWT) on socket healing after tooth extraction in rats given long-term bisphosphonates. METHODS: Forty male Wistar-Albino rats were used in this experimental study. About 0.1 mg/kg zoledronic acid was administered intraperitoneally to all animals 3 times per week for 8 weeks. Four groups were made which were control, LLLT, ESWT, and ESWT+LLLT. Upper right first molar teeth extraction was performed in all groups; no treatment was given to the control group after molar tooth extraction. About 810 nm wavelength GaAlAs laser was used in LLLT group. In ESWT group, 1000 pulses, 0.21 mJ/mm ESWT was applied, and the 2 treatment methods were applied to the last ESWT+LLLT group at the same time. All the 4 groups were divided into 2 subgroups according to sacrification time 4 and 8 weeks. Steorologic, histologic, and immunohistochemical examinations were performed. RESULTS: The highest new bone volume was observed in the early LLLT+ESWT. New vessel volume and CD31 expression were found to be high in the LLLT group. matrixmetalloproteinaze (MMP)-2 expression was found increased by the application of LLLT and ESWT. CONCLUSION: The LLLT and ESWT have similar effect on socket healing in the early period and that co-use is more effective upon healing. The LLLT has been shown to increase CD31 expression and increase vascularization and soft-tissue healing.

Effect of Electrohydraulic Extracorporeal Shockwave Therapy on the Repair of Bone Defects Grafted With Particulate Allografts.

This study determined the effect of electrohydraulic extracorporeal shockwave therapy (ESWT) on the healing of mandible defects repaired using particulate allogenic bone grafts. This study included 20 male Wistar rats aged 12 weeks. In all the animals, a critical-sized defect of 4-mm diameter was created in the mandible and the defect area was filled with particulate allograft. Next, the rats were divided into 2 groups, allograft (G) (n = 10) and allograft + ESWT (GE) (n = 10). On days 3, 5, and 7 after the grafting, rats in the GE group received ESWT involving 200 pulses with an energy flux density of 0.19 mJ/mm. Five rats in each group were sacrificed at the end of week 4 and at the end of week 8. Defect areas were examined radiologically by performing high-resolution computed tomography and stereologically by using the Cavalieri method. Obtained data were compared by performing statistical analysis. Radiological evaluation showed that bone density was higher in rats in the G group than in those in the GE group at week 4. In contrast, bone density was higher in rats in the GE group than in those in the G group at week 8. Stereological examination showed that new bone, connective tissue, and capillary volumes were higher in rats in the GE group than in those in the G group at both weeks 4 and 8. The authors' results indicate that repeated doses of ESWT accelerate the healing of bone defects repaired using allogenic bone grafts.

Efficacy of Extracorporeal Shockwaves Therapy on Peripheral Nerve Regeneration.

PURPOSE: This study was conducted to determine the effects of different doses and methods of extracorporeal shock wave treatment (ESWT) on the sciatic nerve regeneration of rat model using unbiased quantitative stereological techniques and to know which method and dose were effective. METHODS: Twenty-five Wistar albino rats were used in the experiment. All animals were randomly divided into 5 groups. To the first group (control, n = 5) ESWT and surgery were not applied. To 2nd group (E300*2, n = 5), twice doses of 300 impulses uESWs (unfocused) were applied. To 3rd group (E500*2, n = 5), twice doses of 500 impulses uESWs (unfocused) were applied. To 4th group (E300*2, n = 5), twice doses of 300 impulses of fESWs (focused) were applied. To 5th group (E500*2, n = 5), twice doses of 500 impulses of fESWs (focused) were applied. Rats were sacrificed and nerve samples analyzed on the 22nd day following the operation. RESULTS: There is a variable increase in the axon numbers among the shockwave treated groups in compare to the control group. The focused groups showed better improvement and the 300-focused group has shown the highest regeneration rate. CONCLUSION: The authors found that ESWT promotes nerve regeneration, increases the thickness of the myelin sheath and that the most effective result is in the 300 shock wave.

Comparison of the Regenerative Effects of Platelet-Rich Fibrin and Plasma Rich in Growth Factors on Injured Peripheral Nerve: An Experimental Study.

PURPOSE: The aim of this study was to investigate the effects of platelet-rich fibrin (PRF) and plasma rich in growth factors (PRGF) on peripheral nerve injury in the early period of healing. MATERIAL AND METHODS: Thirty Wistar albino rats were used in this study. Rats were divided into control (C), damaged (D), PRF, and PRGF groups. The left sciatic nerves of each group were identified as group C. Crush-type injury was performed on the right sciatic nerves of the D, PRF, and PRGF groups. In the PRF and PRGF groups, blood 2 mL was obtained to prepare the PRF and PRGF and the biomaterials were applied to the injured nerve area. After 8 weeks, functional, electrophysiologic, and stereological evaluations were performed. RESULTS: For the electrophysiologic evaluation, the latency and amplitude values in the D, PRF, and PRGF groups were significantly lower than those in the C group (P > .05). According to the sciatic functional index result, there were significant differences between groups D and PRF and between groups D and PRGF (P = .000). For the stereological evaluations, although no significant difference was observed between the PRGF and C groups (P > .05), a significant difference was observed among the D, PRF, and PRGF groups for myelinated axon number. There were significant differences between groups D and PRF and between groups D and PRGF for axon area (P = .021 and .001, respectively). No significant difference was observed among the D, PRF, and PRGF groups for myelin sheath thickness and ratio of axon area to myelin sheath thickness (P > .05). CONCLUSIONS: The results of this study suggest that PRGF increases nerve regeneration in the early period of healing and that the limited early action of PRF should be re-evaluated in the late period.

The Effect of Unfocused Extracorporeal Shock Wave Therapy on Bone Defect Healing in Diabetics.

AIM: The purpose of this study was to evaluate the effect of the unfocused extracorporeal shock wave therapy (ESWT) on healing of mandible ramus defects in diabetic rats. MATERIAL AND METHOD: Forty male Wistar albino rats were used in the experiment. All animals were randomly divided into 2 main groups, nondiabetic and diabetic. Critical-sized defects were created on ramus in all rats. ESWT was performed to half of rats in each group at 3 sessions after surgery. Animals were euthanized at either fourth or eighth week. Stereological and radiologic examination was performed. Data were statistically analyzed by one-way variance analysis and Tukey post-hoc test. RESULTS: Hounsfield Unit values were higher in DE group than DE group in both 8-week and 4-week groups (P > 0.05). In both 4-week and 8-week diabetic groups, higher value was observed when compared with nondiabetic groups (P > 0.05). According to stereological results, in 4-week groups, there was a higher new bone, connective tissue, and neovascularization volume in DE group than DE group and in DE group than DE group. These results are similar for the 8-week groups except NV volume. CONCLUSION: It was found that ESWT application has no positive effect on the healing of critical-sized bone defects in nondiabetics whereas promising effects in diabetics were observed.

The Effect of Different Doses of Extracorporeal Shock Waves on Experimental Model Mandibular Distraction.

OBJECTIVE: Distraction osteogenesis (DO) is widely used treatment for the bone deformities. In addition extracorporeal shock wave therapy (ESWT) is a new perspective on noninvasive modalities of management of the bone regeneration. We examined the effects of 2 different single doses of ESWT on the consolidation period of DO of the rabbit mandible using stereological, radiological and immunohistochemical methods in the present study. METHODS: DO was performed unilaterally in the mandible of 18 New Zealand rabbits (6 months' old, weighing between 2.5 and 3 kg). The distraction zone of the mandible has received no treatment as controls. Group 2 (ESWT 500) received ESWT (single dose of 500 impulses 0.19 mJ/mm energy flux intensity and 2155 mJ totally) were applied on the first day of the consolidation. Group 3 (ESWT 1000) treated with ESWT (single dose of 1000 impulses0.19 mJ/mm energy flux intensity and 4310 mJ totally) were applied on the first day of the consolidation period. After the sacrification, radiologically bone mineral density, new bone formation, new fibrous tissue, and new vessel formation were analyzed using unbiased stereological methods. RESULTS: It was found a statistically significant difference between the study groups and control group in the bone mineral density measurements and the highest values were in the ESWT1000 group. In terms of stereological analysis, there was a significant difference between the study groups and control group (P = 0.00). The new capillary volume was highest in the E1000 group. Additionally, significant differences were found in point of the capillary volumes between the groups control and ESWT500 (P = 0.001), control and ESWT1000 (P = 0.000), ESWT500 and ESWT1000 (P = 0.040), respectively. CONCLUSIONS: A total of 1000 impulses ESWT may induce the growth factors to enhance the newly formed bone regeneration.

Effects of Different Tissue Adhesives in Treating Calvarial Bone Defects.

The purpose of this study is to investigate the potential of the 2 different tissue adhesive materials as a barrier for guided bone regeneration and to compare them with resorbable collogen membrane on autogenous grafted critical-sized cortical bone defects. Twenty-four rats were divided into 3 groups: Group M, Group G, and Group B. A 5-mm diameter critical-size defect was created in the calvarium of each animal. All defects were filled by autogenous graft harvested from tibia. In group M, resorbable collogen membrane was applied to defect area. In groups G and B, defects were closed by Glubran2 and Bioglue. All animals were euthanized at 28 days postoperative. Stereologic analyses were performed. New bone area and connective tissue volumes were measured. Mean new bone volumes were 0.97 ±â€Š0.28, 0.59 ±â€Š0.2, and 0.8 ±â€Š0.32 mm in groups M, G, and B, respectively. The differences between groups were not statistically significant (P > 0.05). In group M, mean connective tissue volumes were 4.25 ±â€Š0.7 mm, in groups G and B, 2.9 ±â€Š1.82 and 4.54 ±â€Š0.64 mm. Connective tissue volume differences were not statistically significant between groups. Glubran2 and Bioglue may play a role as a barrier for guided bone regeneration in treatment of critical size defects.

The Local Effect of Puerarin on Critical-Sized Calvarial Defects.

Pueraria, the root of Pueraria lobata, is a commonly used herb in alternative medicine. This study evaluates the effect of puerarin and autogenous graft material combination on bone regeneration in calvarial critical-sized bone defects. Twenty-four rats were randomly divided into 3 groups of 8 rats each. A 5-mm diameter critical-sized defect was created in the calvarium of each animal. In group C, defects were left unfilled and were allowed to heal spontaneously without the use of any grafting material. Critical-sized bone defect created in animals receiving no treatment. In group ABG, defects were filled with autologous bone graft only. In group P-ABG, defects were filled with autologous bone graft and puerarin combination. All animals were euthanized at 28 days postoperative. Stereologic analyses were performed. New bone area and connective tissue volumes were measured. Stereologic analysis showed that the difference between grafted groups (P-ABG and ABG) and group C was statistically significant with a mean bone formation of 1.13 ±â€Š0.09, 1.11 ±â€Š0.11, and 0.31 ±â€Š0.09 mm respectively (P ≤0.05). The connective tissue volumes were also statistically higher in groups P-ABG and ABG (P ≤0.05). Puerarin has positive effect on new bone formation in autogenous grafted critical-sized bone defects.

The histopathological and stereological assessment of the effect of topically administered leptin on cerebral vasospasm in an experimental subarachnoid hemorrhage model

Background/aim: Cerebral vasospasm is a term that refers to prolonged, slowly progressing but reversible pathological narrowing of cerebral arteries occurring several days after subarachnoid hemorrhage (SAH), usually accompanied by a decrease in perfusion distal to the affected artery. Leptin is an endogenous polypeptide hormone that can be carried freely and bound to protein in the blood. Materials and methods: We investigated the superiority of topical application of leptin that may make a contribution to the development of new treatment modalities for unconscious patients in brain injury intensive care units and its preventive effect, which is considered to have multifactorial pathogenesis on cerebral vasospasm occurring after SAH via stereological studies of the basilar artery. Results: When mean serum leptin levels of the groups were compared, statistically significant differences were observed between the control and topical leptin-treated groups in favor of the treated groups with respect to serum leptin levels (P < 0.05). In the topical leptin-applied group, a significant difference in favor of vasodilatation was observed in the measurements of the basilar artery luminal area (P < 0.05). Conclusion: In accordance with the results, the topical administration of leptin can be used in the prevention of vasospasm, especially in unconscious patients with subarachnoid hemorrhage.

The Effect of Local Rosuvastatin on Mandibular Fracture Healing.

Mandibular fracture is the most common injury seen in facial fractures and plays an important role for oral and maxillofacial surgery department. The purpose of this study is to investigate the potential of the local administration of rosuvastatin (RSV) on mandibular fracture healing in rats. Thirty-two rats were divided into 4 groups: group C-14 (control), group R-14, group C-28 (control), and group R-28. A unilateral standard vertical osteotomy was performed right side of the mandibula extending from the tooth to the mandibular basis for each animal. In groups C-14 and C-28 sterile saline treated absorbable collogen sponge was applied to the fracture area, in groups R-14 and R-28 absorbable collogen sponge with saline solution containing 1 mg RSV was applied to the fracture area. Animals in groups C-14 and R-14 were euthanized on the 14th day, groups C-28 and R-28 were euthanized on the 28th day after operation. Stereologic analyses were performed. New bone area and connective tissue volumes were measured. Stereologic analysis showed that group R-14 had significantly more new bone at 2 weeks compared with group C-14. Connective tissue volumes were also significantly higher in R-14. New bone and connective tissue volume differences were not statistically significant between groups C-28 and R-28. Locally administered RSV enhances early bone regeneration on mandibular fracture in rats.

Effect of Electromagnetic Wave on Bone Healing in Fixed and Unfixed Conditions.

Mobile phones have come into daily life and are now one of the most frequently used devices for communication. The aim of this study was to evaluate possible effect of electromagnetic wave (EMW) with and without fixation material on bone healing.Forty male rats were exposed to fracture on tibia bone and were randomly divided into 4 groups as E(+)K(+), E(+)K(-), E(-)K(+), and E(-)K(-) where E(+) means EMW exposure and K(+) means Kirschner wire fixation. At the end of study tibia samples were taken from all the groups for the quantitative evaluation of regeneration.Significant difference was found between Group E(+)K(+) and E(-)K(+) in terms of both new bone and capillary volume.Electromagnetic wave may be harmful for bone healing with fixation whereas it has no same effect on bone regeneration without fixation.

Therapeutic Effects of Sildenafil on Experimental Mandibular Fractures.

OBJECTIVES: No previous studies have examined the effect of sildenafil on fracture healing. This study was designed to investigate the effect of sildenafil on the fracture healing process. METHODS: Thirty-six female Sprague-Dawley rats (3-month-old) were used in this study. Animals were randomly divided into 2 groups based on treatment duration (1 week versus 4 weeks) and each group was then divided further into 2 subgroups, control (C) and study (S) groups. Group C (C1, C2) was treated daily with saline solution and group S (S1, S2) was treated daily with 10 mg/kg of sildenafil. Histologic, histomorphometric, radiological, and immunohistochemical analyses were performed at 1 week and 4 weeks after a fracture. RESULTS: The sildenafil group showed a significant increase in fracture healing scores (P = 0.00). The authors observed a transition from fibrous callus to cartilage tissue and immature bone tissue in group S1; and an increased transition of cartilage tissue to completely immature bone tissue in group S2, both of which were administered sildenafil. The strong expression of bone morphogenetic protein 2 and col-1 was observed in the fibrous matrix and osteoblasts within areas of new bone formation, especially in group S1. This group also showed an increase in bone density measurements at 1 week that was statistically significant (P = 0.03). CONCLUSIONS: Sildenafil accelerates fracture healing and can be used as a supporting factor in the improvement of fracture healing under various conditions.

The Effect of Epigallocatechin Gallate on Flap Viability of Rat Perforator Abdominal Flaps.

Background Epigallocatechin gallate (EGCG) is a substance abundant in green tea. In this study, the effects of EGCG on perforator flap viability were investigated. Methods A total of 40 rats were assigned to four groups of 10 each. In each subject, a 4 × 6 cm abdominal skin flap was raised and adapted back onto its place. In the control group, no further procedures were taken. In the flap group, 40 mg/kg/d EGCG was injected into the flap. In the gavage group, 100 mg/kg/d EGCG was given through a feeding tube. In the intraperitoneal group, 50 mg/kg/d EGCG was injected intraperitoneally. On the 7th postoperative day, flaps were photographed and the viable areas were measured and compared via a one-way analysis of variance. Results The ratios of viable and contracted flap area were 9.15/12.01, 4.59/16.46, 11.56/11.20, and 11.65/10.77 cm(2) for the control, flap group, gavage group, and intraperitoneal group, respectively. While the flap group yielded the worst results in the sense of flap contraction and viability (p < 0.001), the gavage and intraperitoneal groups were significantly better than those of the control group (p = 0.03). Histologically, epidermal, papillary dermal, and capillary tissue volumes were evaluated. In comparison to the control group, the flap group yielded significantly increased epidermal and dermal volumes (p = 0.03), however, these values were significantly decreased (p = 0.04) in the gavage and intraperitoneal groups. Capillary volumes were significantly decreased in EGCG treatment groups (p < 0.01). Conclusion Our experiment has shown that oral and intraperitoneal administration of EGCG increases the perforator flap viability when compared with controls, while direct injection decreases the viability.

Detrimental Effects of Sterilization Types on Single-Use Coronary Angioplasty Catheters for Reuse: An Electron Microscopic Study.

Objective: Reuse of medical devices poses risks concerning technical issues and patient safety. In this study, we aimed to examine the structural changes in catheters that occur due to the reuse with the aid of electron microscopy. Materials and Methods: The effects of hydrogen peroxide (HP) and ethylene oxide (EO) sterilization on four percutaneous transluminal coronary angioplasty (PTCA) catheters and control PTCA catheters were examined by scanning electron microscope (SEM). Each catheter sample was divided into four parts during the SEM examination, and a total of 20 pieces were examined. Catheters were reprocessed through every regular sterilization step and used solely for the study, not in patients. Statistical evaluations of histological scoring made on images obtained from scanning electron microscopic images were made using the GraphPad Prism 8 program. Results: Electron microscopical examination showed that HP sterilization caused more robust and deeper lines compared to EO. These distortions increased directly with the increase in the reprocessing cycle. In EO, no significant damage was detected within five cycles in contrast to HP; however, the harmful effects of EO were seen over five cycles. Unprocessed samples had no damage. Outer and inner deterioration was significantly higher in the EO>5 group and HP>5 group than in the control group. However, the bacterial contamination score in the EO>5 group was higher than the control group. Conclusion: Our findings showed that HP and EO sterilizations caused some deterioration in the inner and outer surfaces of PTCA catheter samples. We recommend reprocessing using EO, the least damaging method, when necessary, and paying attention not to exceed five cycles when necessary.

Pigment epithelium-derived factor enhances peripheral nerve regeneration through modulating oxidative stress and stem cells: An experimental study.

Peripheral nerve injury is common and negatively affects an individual's quality of life. Drugs used for peripheral nerve regeneration should aim to eliminate symptoms such as neuropathic pain and have therapeutic effects. In recent studies, pigment epithelium-derived factor (PEDF) has been considered an essential therapeutic agent because of its potential neuroprotective properties. In this study, we aimed to investigate the efficacy of locally applied PEDF for peripheral nerve regeneration. Twenty-four Wistar albino male rats were used. The study groups included Injury (n = 12) and Injury+PEDF (n = 12). An injury model was created by applying 50 N pressure to the right sciatic nerves in groups, and 10 µg/kg local PEDF was injected into the Injury+PEDF group. After 28 days of recovery, functional tests and stereological, immunohistochemical, and biochemical analyses were performed. A significant difference was found between the Injury and Injury+PEDF groups in amplitude, whereas no difference was found in latency. The number of myelinated axons and the myelinated axon area increased significantly in the Injury+PEDF group, while no statistically significant difference was found in myelin sheath thickness. Superoxide dismutase, catalase, and glutathione peroxidase activities were increased by PEDF, whereas they were suppressed in mesenchymal stem cells. PEDF exerts functional, quantitative, and antioxidative effects on sciatic nerve injury during neuroregeneration. In addition, when oxidative stress parameters were examined, it was seen that PEDF reduced oxidative stress following sciatic nerve injury.

The effects of curcumin and blueberry on axonal regeneration after peripheral nerve injury.

The purpose of this study was to analyze the axonal regeneration and therapeutic effects of curcumin and blueberry administration following peripheral nerve injury using stereological, electron microscopic and electrophysiological methods. Animals in were assigned into one of four groups - control (Cont), injury (Inj), injury+curcumin (Cur) and injury+blueberry (Blue). Following the induction of sciatic nerve crush injury (75 Newtons for 5 s) in the Inj, Cur, and Blue groups, the rats in the Cur group received intraperitoneal injection of 30 mg/kg curcumin (Sigma C1386) and the rats in the Blue group received 4 g/kg blueberry by gavage over a four-week period. The rats in the Cont and Inj groups were not exposed to any substance. All animals were given standard chow. Sciatic functional index analyses were performed on the 14th and 28th days after injury, and electromyography (EMG) results were recorded. Stereological analysis of the nerve was performed under light microscopy. Light and electron microscopies were used for the histopathological evaluation of the sciatic nerve. Analysis of myelinated axon numbers revealed no significant differences between the Inj group and the Cur and Blue groups. However, a significant difference was observed between the Blue and Inj groups in terms of axonal areas. EMG test results differed between the Blue and the Inj groups (p < 0.05), but no significant difference was observed between the Inj and Cur groups. Electron microscopic analysis revealed protective effects of curcumin and blueberry treatment after injury. The use of the curcumin and blueberry may represent a supportive approach to the protection of nerve fibers after peripheral nerve crush injury.

Effects of NGF and Photobiomodulation Therapy on Crush Nerve Injury and Fracture Healing: A Stereological and Histopathological Study in an Animal Model.

Study Design: A stereological and histopathological study in an animal model. Objective: This study explores the effects of the nerve growth factor and photobiomodulation therapy on the damaged nerve tissue and fracture healing. Methods: A total of 24 rabbits were divided into 4 groups: control group (n = 5), nerve growth factor (NGF) group (n = 7), photobiomodulation (PBMT) group (n = 6), and nerve growth factor and photobiomodulation therapy (NGF+PBMT) group (n = 6). The vertical fracture was performed between the mental foramen and the first premolar, and the mental nerve was crushed for 30 seconds with a standard serrated clamp with a force of approximately 50 N in all groups. The control group received an isotonic solution (.02 mL, .09% NaCl) to the operation site locally. The NGF group received 1 µg human NGF-ß/.9% .2 mL NaCl solution for 7 days locally. The PBMT group received PBMT treatment (GaAlAs laser, 810 nm, .3 W, 18 J/cm2) every 48 hours for 14 sessions following the surgery. The NGF+PBMT group received both NGF and PBMT treatment as described above. After 28 days, the bone tissues and mental nerves from all groups were harvested and histologically and stereologically analyzed. Results: According to the stereological results, the volume of the new vessel and the volume of the new bone were significantly higher in the PBMT group than in other groups (P < .001). According to the histopathological examinations, higher myelinated axons were observed in experimental groups than in the control group. Conclusions: As a result, PBMT has beneficial effects on bone regeneration. Based on the light microscopic evaluation, more regenerated axon populations were observed in the NGF group than in the PBMT and PBMT + NGF groups in terms of myelinated axon content.

Effects of Combining Plasma Rich in Growth Factors with Different Bone Grafts on Early Bone Healing: An Experimental Study.

PURPOSE: To histologically and radiographically investigate the effect of plasma rich in growth factor (PRGF) mixed with bone grafts on ossification in the early period. MATERIALS AND METHODS: A total of 12 New Zealand male rabbits (weighing between approximately 2.5 to 3 kg) were included in this study. Subjects were randomly divided into two sets of groups: control and experiment. Autograft, DFDBA (demineralized freeze-dried bone allograft), and DBBM (deproteinized bovine bone mineral) were applied to different defects in the control groups, and autograft + PRGF, DFDBA + PRGF, and DBBM + PRGF were applied in the experimental groups. All subjects were euthanized 28 days after surgery. The volumes of the bone, new connective tissue, and new capillaries were evaluated stereologically, and the bone density in the defects was investigated radiographically. RESULTS: Regarding the stereologic evaluation, the volumes of the bone and capillaries were significantly higher in the experimental groups than in the control groups. In contrast, the connective tissue volume was considerably lower (P < .001, in all groups). Similarly, radiographic examinations showed that the bone density measurements in the experimental groups were higher than in the control groups. However, these differences were statistically significant only between the DFDBA + PRGF and DFDBA groups (P < .011). CONCLUSIONS: The present study provides evidence that the addition of PRGF to autograft, DFDBA, and DBBM enhances osteogenesis in the early period compared to using these grafts alone. It also accelerates the remodeling of connective tissue to bone in defects. Int J Oral Maxillofac Implants 2023;38:569-575. doi: 10.11607/jomi.9858.