A Case Report of Oral Bisphosphonate Treatment for Osteoporosis Leading to Atypical Femoral Fracture and Pathologic Mandibular Fracture.

BACKGROUND Bisphosphonates inhibit bone resorption in patients with postmenopausal osteoporosis and reduce osteoporotic fracture incidence. Medication-related osteonecrosis of the jaws (MRONJ) and atypical femoral fractures (AFF) are both rare but serious adverse effects of anti-resorptive drugs (ARD) such as bisphosphonates. The most advanced form of MRONJ is termed stage 3 and can lead to severe local sequelae like pathologic mandibular fractures (PMF). This study reports a case of MRONJ-related PMF and AFF with osteomyelitis secondary to bisphosphonate treatment for osteoporosis. CASE REPORT A 63-year-old white woman was diagnosed with PMF related to MRONJ stage 3 during treatment of an AFF with osteomyelitis. She had been treated for postmenopausal osteoporosis with 70 mg of alendronate weekly for 2 years. The PMF was treated by stable internal fixation combined with debridement and sequestrectomy, but further debridement was required and 2 mandibular implants were then removed. Postoperative recovery was uneventful and the mandibular infection was controlled after the second surgery. Three weeks later, she was discharged from the hospital, instructed to discontinue the use of alendronate, and referred for 30 sessions of hyperbaric oxygen therapy. At the 3-year follow-up, the PMF was completely healed without signs of mandibular infection or bone exposure. CONCLUSIONS This report raises awareness of both MRONJ and AFF as possible adverse effects of short-term bisphosphonate therapy for postmenopausal osteoporosis, and highlights the importance of dental and orthopedic follow-ups. It is crucial to emphasize the need for early diagnosis and treatment to prevent MRONJ progression to PMF.

The Promoting Effect of a Local Pulsatile Parathyroid Hormone Delivery on Healing of the Mandibular Fracture in Rats.

Parathyroid hormone (PTH) can promote bone formation and mineralization in mandibular fractures, and is systemically administered through daily injections. In this study, the local delivery of PTH using carboxymethyl chitosan/polyvinyl alcohol and alginate was investigated. Bovine serum albumin was used as a drug substitute, and the delivery system was verified to release drugs in a pulsed rhythm. After the delivery system was subcutaneously implanted in Sprague-Dawley (SD) rats, no rejection reaction was detected, indicating that it has good biocompatibility and biodegradability in vivo. Then, an SD rat model of mandibular fracture was established, and 24 rats were randomly divided into two groups. The control group was reduced and fixed with screws and a microplate, and the experimental group received pulsatile PTH release system (14 µg PTH) + screws and microplate fixation. The animals were euthanized on postoperative weeks 1-4. Observation of gross specimens, digital radiography, and hematoxylin and eosin showed that the local PTH pulsatile release system promoted osteogenesis and accelerated fracture healing. In summary, PTH can be loaded by biomaterials to locally target the fracture and stimulate bone formation. Moreover, the pulsatile PTH release system provides a potential therapeutic protocol for mandibular fracture. Impact statement Our study prepares a drug release system that could impulsively release parathyroid hormone. The system could enhance bone regeneration in rats with mandibular fracture. These data provide a foundation for future studies aimed to understand and optimize the use of bioactive molecule pulsatile delivery for bone regeneration and tissue engineering applications.

Nota técnica: planificación virtual 3D en el tratamiento de fractura doble en mandíbula atrófica / Technical note: 3D virtual planning for atrophic mandible double fracture reduction

El uso de la planificación virtual ha demostrado en varios estudios una mayor predictibilidad de los resultados quirúrgicos, así como una reducción del tiempo quirúrgico y la posibilidad de comparar nuestros resultados con los esperados mediante una comparación con un TC postoperatorio. En esta nota técnica se describe cómo planificar de forma virtual la cirugía mediante tecnología 3D “in house” de fracturas en mandíbulas atróficas usando un software de uso libre. (AU)

The use of virtual planning has demonstrated in several studies greater predictability of surgical results, as well as a reduction in surgical time. In addition, we have the possibility to compare our results with the planning through a comparison with a postoperative CT. This technical note aims to describe how to plan surgery for fractures in atrophic mandibles using pre-surgical 3D technology and a free software. (AU)

Antibiotic use in mandibular fracture surgery - An international survey and a review of the literature.

OBJECTIVE: To clarify antibiotic use by oral and maxillofacial surgeons in mandibular fracture patients and evaluate practices based on scientific evidence. MATERIAL AND METHODS: We assessed antibiotic use in simple symphysis and angle mandibular fractures among oral and maxillofacial surgeons in the Nordic countries through an e-survey. In addition, we performed a literature review of antibiotic administration in mandibular fracture surgery. RESULTS: A total of 41 oral and maxillofacial surgeons who treat mandibular fractures responded to the questionnaire. Timing and duration of antibiotic use varied. The duration of postoperative antibiotic treatment ranged from 1 to 7 days (mean 5.6 days). Respondents' practices were not in concordance with scientific evidence. According to previous studies, restricting antibiotic exposure to a maximum of 24 hours postoperatively was not related to a higher risk of surgical site infections. No articles described a benefit of prolonged postoperative antibiotic therapy. CONCLUSIONS: Antibiotic use in connection with mandibular fracture treatment varied in the Nordic countries and antibiotic practices are not in concordance with the current literature. Restricting antibiotic exposure to a maximum of 24 hours postoperatively should be considered. Clear guidelines for antibiotic prophylaxis as part of the surgical management of mandibular fractures are required.

The efficacy of teriparatide (Cinnopar®) on bone repair in mandibular fractures: A single blinded randomized clinical trial.

This study focused on the effects of teriparatide (CinnoPar) on healing and postoperative complications in mandibular bone fractures. In this single-blind randomized controlled trial, 30 patients with a mandibular fracture hospitalized for open reduction internal fixation were randomly assigned to the intervention (I) (n = 15) and control (C) (n = 15) groups. Both groups received daily acetaminophen and cephalexin for 1 week. For 1 month, Group I received daily subcutaneous teriparatide injections. The Radiographic Union Scale of the Mandible (RUSM) was used to assess mandibular bone fusion subjectively, and the Hounsfield unit (HU) was used to objectively assess radiodensity in a computed tomography (CT) scan. In both groups, the visual analog scale (VAS) score was used to assess postoperative complications such as pain, swelling, wound opening, pus secretion, and bitter taste. There was no significant difference in bone repair between the two groups in this study (P > 0.05). Teriparatide also had no effect on the postoperative complication rate in the control group (P > 0.05). Within the limitations of the study it seems that in mandibular fractures, teriparatide did not affect bone fusion or postoperative complications, so its use is not recommended for better bone fusion and fewer postoperative complications of mandibular fracture during the first month.

Evaluation of the efficacy of salmon calcitonin nasal spray on bone healing following open reduction and internal fixation of mandibular fractures - A randomized controlled trial.

The objective of this study was to assess the efficacy of calcitonin spray on bone healing following open reduction internal fixation (ORIF) of mandibular fractures. Fourteen patients were subdivided into a study group and a control group. A standardized surgical protocol for ORIF was followed. Postoperatively, salmon calcitonin nasal spray was administered to only the study group. The outcome parameters assessed were serum osteocalcin, pain, and radiographic bone healing. Serum osteocalcin was assessed pre- and postoperatively. Postoperative pain was documented using a visual analogue scale (VAS) on the 7th, 14th, 23rd, and 30th days. An orthopantomogram was used to score fracture healing at four time intervals, as follows: 1 - absence of callus; 2 - presence of minimal callus; 3 - considerable callus; and 4 - complete fusion of fracture. Pain scores were lower for the study group, with no pain from the fifth day, while the control group produced a mean score for day 5 of 2.43 ± 0.98 (p = 0.001). Mean postoperative serum osteocalcin levels were higher for the study group (67.82 ± 8.89) compared with the control group (57.69 ± 6.22; p = 0.029). Bone healing at 12 weeks postoperatively was level 4 for 28.6% of patients in the study group and level 3 for 71.4%. In comparison, 85.7% in the control group demonstrated level 3 healing, while 14.3% remained at level 2 (p = 0.462). Within the limitations of the study, it can be concluded that intranasal salmon calcitonin spray reduces postoperative pain and facilitates fracture healing, although its economic efficiency is still to be proven.

Parathyroid hormone promotes cartilage healing after free reduction of mandibular condylar fractures by upregulating Sox9.

After high fractures of the mandibular condyle, the insufficient blood supply to the condyle often leads to poor bone and cartilage repair ability and poor clinical outcome. Parathyroid hormone (PTH) can promote the bone formation and mineralization of mandibular fracture, but its effects on cartilage healing after the free reduction and internal fixation of high fractures of the mandibular condyle are unknown. In this study, a rabbit model of free reduction and internal fixation of high fractures of the mandibular condyle was established, and the effects and mechanisms of PTH on condylar cartilage healing were explored. Forty-eight specific-pathogen-free (SPF) grade rabbits were randomly divided into two groups. In the experimental group, PTH was injected subcutaneously at 20 µg/kg (PTH (1-34)) every other day, and in the control group, PTH was replaced with 1 ml saline. The healing cartilages were assessed at postoperative days 7, 14, 21, and 28. Observation of gross specimens, hematoxylin eosin staining and Safranin O/fast green staining found that every-other-day subcutaneous injection of PTH at 20 µg/kg promoted healing of condylar cartilage and subchondral osteogenesis in the fracture site. Immunohistochemistry and polymerase chain reaction showed that PTH significantly upregulated the chondrogenic genes Sox9 and Col2a1 in the cartilage fracture site within 7-21 postoperative days in the experimental group than those in the control group, while it downregulated the cartilage inflammation gene matrix metalloproteinase-13 and chondrocyte terminal differentiation gene ColX. In summary, exogenous PTH can stimulate the formation of cartilage matrix by triggering Sox9 expression at the early stage of cartilage healing, and it provides a potential therapeutic protocol for high fractures of the mandibular condyle.

Surgical Infection Society Guidelines for Antibiotic Use in Patients with Traumatic Facial Fractures.

Background: Facial fractures are common in traumatic injury. Antibiotic administration practices for traumatic facial fractures differ widely. Methods: The Surgical Infection Society's (SIS's) Therapeutics and Guidelines Committee convened to develop guidelines for antibiotic administration in the management of traumatic facial fractures. PubMed, Embase, and the Cochrane database were searched for pertinent studies. Pre-operative antibiotics were defined as those administered more than 1 hour before surgery. Peri-operative antibiotics were those administered within 1 hour of the start of surgery depending on the type of antibiotic and as late as ≤24 hours after surgery. Post-operative antibiotics were defined as those administered >24 hours after surgery. Prophylactic antibiotics were those administered for >24 hours without a documented infection. Evaluation of the published evidence was performed with the GRADE system. Using a process of iterative consensus, all committee members voted to accept or reject each recommendation. Results: We recommend that in adult patients with non-operative upper face, midface, or mandibular fractures, prophylactic antibiotics not be prescribed and that in adult patients with operative, non-mandibular fractures, pre-operative antibiotics likewise not be prescribed. We recommend that in adult patients with operative, mandibular fractures, pre-operative antibiotics not be prescribed; and in adult patients with operative, non-mandibular facial fractures, post-operative (>24 hours) antibiotics again not be prescribed. We recommend that in adult patients with operative, mandibular facial fractures, post-operative antibiotics (> 24 hours) not be prescribed. Conclusions: This guideline summarizes the current SIS recommendations regarding antibiotic management of patients with traumatic facial fractures.

Effect of Botulinum Toxin Type A on Mandibular Fracture Healing: An Experimental Study in Rabbits.

PURPOSE: The effect of botulinum toxin type A (BTX-A) on fracture healing of the long bones is controversial, and no controlled clinical or experimental study has investigated the effect of BTX-A on mandibular fractures. The purpose of this study was to investigate whether BTX-A injection into the masseter muscles affects bone healing by reducing the displacing forces in an unfavorable mandibular fracture model. MATERIALS AND METHODS: Forty-eight male New Zealand white rabbits were used. Ten units of BTX-A was injected into each masseter muscle in the animals in the BTX-A group, whereas saline solution was injected in the animals in the control group. A unilateral osteotomy and fixation with a microplate were performed. Bone healing was evaluated by radiodensitometric, biomechanical, histologic, and histomorphometric methods after 21 days. RESULTS: The mean bone mineral density in the fracture area was significantly higher in the BTX-A group (P = .038). The mean failure load and bending modulus values were significantly higher in the BTX-A group than in the control group (P = .032 and P = .005, respectively). The mean histologic bone healing scores, bone volume-total volume values, and trabecular diameter values were significantly higher in the BTX-A group than in the control group (P = .001, P = .001, and P = .026, respectively). CONCLUSIONS: BTX-A application into the masseter muscles improves bone healing of a unilateral mandibular fracture in rabbits.

Antimicrobial regimens used in the treatment of mandibular fractures in UK maxillofacial units: changes over 12 years.

In the case of most mandibular fractures, the prescription of antimicrobials for more than 24 hours postoperatively confers no clinical benefit. To establish the prescribing patterns for mandibular fractures in UK OMFS units, and to compare them with those used 12 years ago, we did a telephone and email survey of OMFS units in the UK. Antimicrobials were prescribed for more than 24 hours postoperatively by 76 units (65%) (considerably fewer than the 82 (87%) in 2005). The most commonly prescribed first-line antimicrobial was co-amoxiclav (75%). Although there has been some improvement since 2005, most units still prescribe antimicrobials for periods longer than 24 hours. National collaboration may improve their appropriate prescription.

Evaluation of the effect of teriparatide therapy on mandibular fracture healing in rats with medication-related osteonecrosis of the jaw.

OBJECTIVE: The aim of this study was to evaluate the effect of teriparatide therapy on mandibular fracture healing in rats with medication-related osteonecrosis of the jaw (MRONJ). MATERIALS AND METHODS: To induce MRONJ, a total of 120 rats received intravenous zoledronate 0.06 mg/kg once a week for 6 weeks and their right mandibular first molar was extracted. Eighty of 94 rats with MRONJ were randomly selected and underwent unilateral mandibular osteotomy to replicate a fracture. After surgery, the rats were randomly assigned to T (teriparatide-treated) and C (control) groups. Group T (n = 40) received subcutaneous injection of 2 µg/kg/day teriparatide and group C (n = 40) received the same volume of normal saline until sacrifice. Four and 8 weeks after surgery, 20 rats in each group were sacrificed. Fracture healing was scored using a histological grading system (1 to 10). RESULTS: In group C, at 4 weeks and 8 weeks post-fracture, fibrous and cartilaginous tissues and scant bone formation at the fracture site and lacunae without osteocyte in adjacent mandibular bone were seen. In group T, substantial amounts of new trabecular bone rimmed by osteoblasts and some areas of remodeled mature bone were seen. After 8 weeks, extensive replacement of trabecular bone with mature bone occurred. Except between C4 and C8 groups, the healing score was significantly different between all subgroups. CONCLUSION: Teriparatide therapy successfully improved mandibular fracture healing in rats with MRONJ. However, this study was limited by the use of an animal model whose anatomy, physiology, and drug metabolism might be different from humans. CLINICAL RELEVANCE: The present study showed that teriparatide therapy may be used adjunctive to surgery in the treatment of mandibular fractures in MRONJ patients.

Facing the facts on prophylactic antibiotics for facial fractures: 1 day or less.

BACKGROUND: To evaluate the role of initial prophylactic antibiotics on facial fractures, outcomes were compared between a short course (≤24 hours) of antibiotics to those who received an extended course (>24 hours). METHODS: Adults admitted (2010-2015) to a Level I trauma center intensive care unit with at least one facial bone fracture and major injuries isolated to the head and neck were included. Our primary analysis compared infectious complications of the head or neck (H/N infection) between patients given short or extended courses of antibiotic prophylaxis. Multivariate logistic regression and analysis of propensity score matched pairs were performed. RESULTS: A total of 403 patients were included, 85.6% had blunt injuries and 72.7% had their facial fracture managed nonoperatively. The H/N infection rate was 11.2%. Two hundred eighty patients received a short course of antibiotics and 123 patients received an extended course. Median Injury Severity Score was 14 in both groups (p = 0.78). Patients receiving an extended course of antibiotics had higher rates of H/N infection (20.3% vs. 7.1%, p < 0.001). Factors associated with development of H/N infection included younger age, penetrating injury, open fracture, upper face or mandible fracture, fractures in multiple facial thirds, vascular injury, hypertension, and extended antibiotic course. Multivariate logistic regression identified younger age (odds ratio [OR], 0.98; 95% confidence interval [CI], 0.96-1.00; p = 0.02), multiple facial third fractures (OR, 4.9; 95% CI, 2.4-10.2; p < 0.001), and penetrating mechanism (OR, 3.1; 95% CI, 1.5-6.4; p = 0.003) as independent predictors of H/N infection, but not antibiotic duration. Propensity score-matched analysis found no differences in H/N infection between short and extended antibiotic courses (11.4% vs. 12.5%; p = 1.0). Subgroup analyses demonstrated no differences in H/N infection between short or extended antibiotic courses by injury pattern, mechanism, or treatment (operative or nonoperative). CONCLUSION: These results lead us to believe that we should limit antibiotics to 24 hours or less upon admission for facial fractures. LEVEL OF EVIDENCE: Therapeutic/care management, level IV.

Beneficial Therapeutic Effects of Sildenafil on Bone Healing in Animals Treated with Bisphosphonate.

OBJECTIVES: The purpose of the present study was to evaluate the effects of sildenafil on mandibular fracture healing in animals treated with zoledronic acid by using histologic, histomorphometric, immunohistochemical, and radiodensitometric methods. MATERIALS AND METHODS: A total of 36 Sprague-Dawley rats (3 months old) were used. All animals were treated intraperitoneally with 0.1 mg/kg zoledronate three times per week, for a total of 8 weeks. Postoperatively, the animals were divided into two groups: zoledronate group (Z), which had no treatment applied (n = 18), and zoledronate + sildenafil (ZS), which were treated daily with 10 mg/kg sildenafil (n = 18). Each group was divided into two subgroups and the animals were sacrificed at the end of week 1 (Z1 and ZS1, n = 9) and week 4 (Z4 and ZS4, n = 9) after the operation. Histologic, histomorphometric, immunohistochemical analysis, and radiodensitometry were performed on the test subjects. RESULTS: Sildenafil-treated groups showed a significant increase in fracture healing scores. This result was supported by the densitometric, histologic, histomorphometric, and immunohistochemical findings. CONCLUSIONS: Sildenafil may have positive effects on accelerating and improving fracture healing, and it may be used as a supporting factor in bone healing in patients treated with bisphosphonate (BP) to prevent negative effects of BP's.

Histopathological evaluation of the effect of locally administered strontium on healing time in mandibular fractures: An experimental study.

BACKGROUND: Mandibular fractures are the most common facial fractures. They can be treated by conservative techniques or by surgery. The authors hypothesized that the application of a single local dose of strontium chloride would accelerate the healing of subcondylar mandibular fractures, shorten the recovery time and prevent complications. OBJECTIVES: The aim of the present pilot study was to evaluate the effects of a single local dose of strontium chloride on the healing of subcondylar mandibular fractures in rats. MATERIAL AND METHODS: This randomized experimental study was carried out on 24 male Wistar albino rats. The rats were randomly divided into 3 groups: experimental group 1, receiving 3% strontium chloride; experimental group 2, receiving 5% strontium chloride; and the control group. A full thickness surgical osteotomy was created in the subcondylar area. A single dose of strontium solution (0.3 cc/site) was administered locally by injection on the bone surfaces of the fracture line created. Nothing was administered to the control group. The mandibles were dissected on postoperative day 21. The fractured hemimandibles were submitted to histopathological examination. RESULTS: The median bone fracture healing score was 9 (range: 7-9) in experimental group 1; 8 (range: 7-10) in experimental group 2; and 7.50 (range: 7-8) in the control group. When the groups were compared in terms of bone healing scores, there was a statistically significant difference between experimental group 1 and the control group (p < 0.05). CONCLUSIONS: This study is the first to show that local strontium may have positive effects on the healing of subcondylar mandibular fractures. In the authors' opinion, 3% strontium was beneficial for accelerating facial skeleton consolidation and bone regeneration in rat subcondylar mandibular fractures. This treatment procedure may be combined with closed fracture treatment or a conservative approach.

Evaluation of mandibular fracture healing in rats under zoledronate therapy: A histologic study.

INTRODUCTION: To evaluate fracture healing in mandible of rats under zoledronate therapy. METHODS: A total of 135 Wistar rats were randomly allocated into 3 groups. Group L received two intravenous infusion of 0.06 mg/kg zoledronate 6 weeks apart. Group H received the same dose of zoledronate as group L once a week for 6 weeks and group C were treated with normal saline. Seven days after the last infusion, rats underwent unilateral mandibular osteotomy to replicate a fracture. Fifteen rats from each group were sacrificed 2, 4, and 6 weeks after surgery. Fracture calluses were examined and scored using a histological grading system (1 to 10). RESULTS: After 2 weeks, substantial woven bone and some lamellar bone were seen in control and L groups. In group H, healing was delayed and consisted of fibrous and cartilaginous tissue and some woven bone. After 4 weeks, most of woven bone in control group was replaced with lamellar bone but in group L, comparatively less bone remodeling occurred. In group H, healing process was nearly the same as that at 2 weeks. After 6 weeks, complete bone remodeling was seen in control group. In group L, bone remodeling was under way and in group H, histological findings were nearly the same as those at 2 and 4 weeks. Except for L and control groups at 2 weeks, healing score was significantly different between all corresponding groups. CONCLUSION: Zoledronate therapy delayed healing process of mandibular fracture in rats in a dose-dependent manner.

The potential of stromal cell-derived factor-1 delivery using a collagen membrane for bone regeneration.

Stromal cell-derived factor-1 (SDF-1) is a cytokine that is important in stem and progenitor cell recruitment in tissue repair after injury. Regenerative procedures using collagen membranes (CMs) are presently well established in periodontal and implant dentistry. The objective of this study is to test the subsequent effects of the released SDF-1 from a CM on bone regeneration compared to platelet-derived growth factor (PDGF) in vitro and in vivo. For in vitro studies, cell proliferation, alkaline phosphatase activity, and osteoblastic differentiation marker genes were assessed after MC3T3-E1 mouse preosteoblasts were cultured with CMs containing factors. In vivo effects were investigated by placement of CMs containing SDF-1 or PDGF using a rat mandibular bone defect model. At 4 weeks after the surgery, the new bone formation was measured using micro-computed tomography (µCT) and histological analysis. The results of in vitro studies revealed that CM delivery of SDF-1 significantly induced cell proliferation, ALP activity, and gene expression of all osteogenic markers compared to the CM alone or control, similar to PDGF. Quantitative and qualitative µCT analysis for volume of new bone formation and the percentage of new bone area showed that SDF-1-treated groups significantly increased and accelerated bone regeneration compared to control and CM alone. The enhancement of bone formation in SDF-1-treated animals was dose-dependent and with levels similar to those measured with PDGF. These results suggest that a CM with SDF-1 may be a great candidate for growth factor delivery that could be a substitute for PDGF in clinical procedures where bone regeneration is necessary.

The Influence of Ethanolic Extract of Brazilian Green Propolis Gel on Hygiene and Oral Microbiota in Patients after Mandible Fractures.

Maintenance of proper oral hygiene by dental plaque elimination is one of the most important factors affecting the healing process in postoperative oral wounds. Propolis is a substance produced by bees. Ethanolic extract of propolis has bactericidal, fungicidal, anti-inflammatory, and antioxidative properties. Moreover, it can scavenge free radicals. The purpose of this paper is to demonstrate the efficacy of a gel containing 3% of ethanolic extract of Brazilian green propolis (EEP-B) when used for maintaining oral hygiene in patients with postoperative oral mucosal wounds. The hygiene was assessed using API, OHI, and SBI followed by microbiological examinations. The patients were divided into two groups. Group 1 consisted of those who used a gel containing EEP-B for oral hygiene, and group 2 consisted of those who used a gel without EEP-B. Although improved oral hygiene was noted in both groups, the improvement was markedly greater in the group using gel containing EEP-B. Summing up the results of microbiological examinations, EEP-B has beneficial effect on mouth microflora in postoperative period. Propolis preparations used for oral hygiene allow eliminating microorganisms of pathogenic character and physiological flora microorganisms considered as being opportunistic, with no harmful influence on physiological microflora in oral ecosystem.

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.

Comparison of the effects of dexmedetomidine and remifentanil on potential extreme haemodynamic and respiratory response following mask ventilation and laryngoscopy in patients with mandibular fractures.

OBJECTIVE: The safety profile and efficacy were compared for remifentanil and dexmedetomidine with respect to haemodynamic and respiratory response during mask ventilation and laryngoscopy in patients with mandibular fractures. PATIENTS AND METHODS: Seventy patients undergoing elective mandibular fracture surgery were randomly assigned to the remifentanil group (Group R, n = 35) or the dexmedetomidine group (Group D, n = 35). The primary outcomes were preoperative pain scores caused by jaw movement; haemodynamic response; intubation score; and side effects, such as the incidence of oxygen desaturation and muscle rigidity. Other side effects, such as tachycardia, bradycardia, hypertension and hypotension, were also compared. RESULTS: Preoperative pain scores caused by jaw movement were significantly high for both groups, but there were no statistically significant differences between the groups. The incidence of oxygen desaturation and muscle rigidity was significantly lower in Group D than in Group R (p = 0.025). No significant differences existed between the groups in terms of intubation score, haemodynamics, and other side effects (p > 0.05). DISCUSSION: Dexmedetomidine and remifentanil had equal effectiveness on the control of haemodynamic response due to mask ventilation and intubation in patients with mandibular fractures. However, at the doses used in this study, dexmedetomidine had a significant advantage over remifentanil in terms of respiratory stability.