Factors Influencing Severity of Medication-Related Osteonecrosis of the Jaw: A Retrospective Study.

PURPOSE: The progression of medication-related osteonecrosis of the jaw (MRONJ) is influenced by many factors. This study aimed to identify the clinical risk factors associated with severe MRONJ (stage 3). PATIENTS AND METHODS: The data of patients with MRONJ who were hospitalized between July 2013 and December 2019 were retrospectively analyzed. Demographic and clinical factors were the independent variables, and the clinical stage of MRONJ lesions was the dependent variable. Multivariate logistic regression analysis was performed to identify the risk factors for advanced stage disease (MRONJ stage 3). RESULTS: A total of 79 patients (with 93 MRONJ lesions) were included. In multivariate regression analysis, the risk factors associated with stage 3 MRONJ were age ≤65 years (odds ratio [OR] = 3.968, 95% confidence interval [CI]: 1.280-12.301; P = .017); chemotherapy (OR = 3.687, 95% CI: 1.048-12.972; P = .042); preoperative MRONJ duration ≥12 months (OR = 7.616, 95% CI: 1.865-31.110; P = .005); lesion location in maxilla (OR = 1.150, 95% CI: 1.006-1.315; P = .041); lesion location in posterior jaw, that is, in molar area (OR = 1.384, 95% CI; 1.118-1.715; P = .003); and serum albumin <40 g/L (OR = 6.257, 95% CI: 1.313-29.815; P = .021). CONCLUSIONS: Age ≤65 years, chemotherapy, preoperative MRONJ duration ≥12 months, lesion location in maxilla, lesion location in the molar area, and serum albumin <40 g/L may increase the risk for severe MRONJ.

[Imaging analysis of jaw defects reparation with antigen-extracted porcine cancellous bone].

At present, most of the bone xenograft for clinical application comes from bovine. In recent years, many studies have been done on the clinical application of porcine xenograft bone. The goal of this study was to evaluate the effect of canine mandibular defects reparation with antigen-extracted porcine cancellous bone by imaging examination. Four dogs' bilateral mandibular defects were created, with one side repaired with autologous bone (set as control group) while the other side repaired with antigen-extracted porcine cancellous bone (set as experimental group). Titanium plates and titanium screws were used for fixation. Cone beam computed tomography (CBCT), computed tomography (CT), single-photon emission computed tomography (SPECT) were undertaken at week 12 and 24 postoperatively, and SPECT and CT images were fused. The results demonstrated that the remodeling of antigen-extracted porcine cancellous bone was slower than that of autologous bone, but it can still be used as scaffold for jaw defects. The results in this study provide a new choice for materials required for clinical reparation of jaw defects.

The comparative study of mandibular ramus growth with different treatment methods for intracapsular condylar fracture.

PURPOSE: The purpose of this study was to evaluate mandibular ramus growth after different treatment methods for intracapsular condylar fracture (ICF) of growing goats. METHOD: Twelve 6-month-old goats were randomly divided into 3 groups (n = 4). The right ICF was created and respectively treated with open reduction and internal fixation (ORIF) and closed treatment. No operation was taken in the control group. The maximum mouth opening and height of mandibular ramus were measured immediately and 3 months after operation by 3-dimensional computed tomographic analysis. Results of the 3 groups were compared statistically. RESULTS: Maximum mouth opening in the closed treatment group was significantly reduced 3 months after operation than before operation (P < 0.05), but not in ORIF and control groups (P > 0.05). Heights of mandibular ramus in ORIF and control groups were significantly longer than that in the closed treatment group 3 months after operation (P < 0.05). CONCLUSIONS: Open reduction and internal fixation is an efficient method to treat ICF of growing goats. It has a better effect on maintaining mandibular ramus growth than closed treatment.

Surgical treatment of severe medication-related osteonecrosis of the jaw.

OBJECTIVES: This study aimed to summarize the clinical outcomes of surgical treatment for severe medication-related osteonecrosis of the jaw (MRONJ, stages 2 and 3). METHODS: A retrospective cohort study was conducted to review the patients with severe MRONJ from July 2013 to May 2021. All patients were treated surgically. The characteristics and clinical variables were recorded and analyzed. RESULTS: A total of 104 patients (123 MRONJ lesions) were included, including 42 males and 62 females, aged 64.6±9.1 years. The primary disease was malignant in 91 cases and benign in 13 cases. Forty-three cases (35.0%) were stage 2 lesions, and 80 (65.0%) were stage 3 lesions. Thirty-nine (31.7%) lesions were located in the maxilla, and 84 (68.3%) lesions were located in the mandible. The most commonly used bisphosphonates were zoledronic acid (n=89; 85.6%), followed by alendronate (n=10; 9.6%), and pamidronate (n=10; 9.6%). Antiangiogenic agents were administered in 62 (59.6%) patients. The mean duration of bisphosphonate therapy was 34.7±25.8 months, and the mean duration of drug holiday was 10.1±10.7 months. All operations were performed under general anesthesia. For stage 2 lesions, debridement and saucerization were performed to completely resect the lesions, and the wounds were closed without tension through local mucoperiosteum flaps. For stage 3 lesions, after the lesions were completely resected, the bone defect was covered by reconstruction plate fixation and ipsilateral submandibular gland translocation, iodoform gauze, and buccal fat pad accordingly. The follow-up period ranged from 3 months to 6 years; 81.3% (100/123) of the lesions reached mucosal healing at the last follow-up, whereas wound infection and dehiscence occurred in 18.7% (23/123) of the lesions postoperatively. CONCLUSIONS: Severe MRONJ lesions could be surgically treated to achieve mucosal healing. Vascularized flap reconstruction could be considered if the patient's general condition could tolerate it.

Novel 3D-printing bilayer GelMA-based hydrogel containing BP,ß-TCP and exosomes for cartilage-bone integrated repair.

The integrated repair of cartilage and bone involves the migration and differentiation of cells, which has always been a difficult problem to be solved. We utilize the natural biomaterial gelatin to construct gelatin methacryloyl (GelMA), a hydrogel scaffold with high cell affinity. GelMA is mixed with different components to print a bi-layer porous hydrogel scaffold with different modulus and composition in upper and lower layers through three-dimensional (3D) printing technology. The upper scaffold adds black phosphorus (BP) and human umbilical cord mesenchymal stem cells (hUMSCs) exosomes (exos) in GelMA, which has a relatively lower elastic modulus and is conducive to the differentiation of BMSCs into cartilage. In the lower scaffold, in addition to BP and hUMSCs exos,ß-tricalcium phosphate (ß-TCP), which has osteoconductive and osteoinductive effects, is added to GelMA. The addition ofß-TCP significantly enhances the elastic modulus of the hydrogel scaffold, which is conducive to the osteogenic differentiation of bone marrow mesenchymal stem cells(BMSCs).In vitroexperiments have confirmed that the bi-layer scaffolds can promote osteogenesis and chondrogenic differentiation respectively. And in the rabbit cartilage-bone injury model, MRI and micro-CT results show that the 3D printed bi-layer GelMA composite scaffold has a repair effect close to normal tissue.

A comparative study of the clinical characteristics of patients with medication-related osteonecrosis of the jaw and osteoporosis or malignancy.

OBJECTIVE: This study aimed to compare the clinical characteristics of patients with medication-related osteonecrosis of the jaw (MRONJ) and osteoporosis vs malignancy. STUDY DESIGN: The study included patients hospitalized with MRONJ between July 2013 and April 2021. These patients were assigned to the osteoporosis or malignancy groups according to their primary disease. Characteristics and clinical variables were recorded and compared. RESULTS: Nighty-one patients (107 MRONJ lesions) were included, with 12 (14 lesions) in the osteoporosis group and 79 (93 lesions) in the malignancy group. The osteoporosis and malignancy groups differed in their respective incubation periods (57.0 ± 42.8 vs 29.3 ± 19.8 months, respectively; P = .048), bisphosphonates cumulative dose (16,487.4 ± 14,268.8 mg alendronate vs 104.0 ± 79.9 mg zoledronic; P = .014), and rate of patients receiving antiangiogenic agents (0/12, 0.0% vs 48/79, 60.8%; P = .001). The groups were similar in their treatment outcomes, measured as successful surgeries (11/12, 91.7% vs 59/79, 74.7%; P = .351). CONCLUSIONS: For stage 2 or 3 MRONJ, patients with osteoporosis (exposed to oral bisphosphonates) developed MRONJ over a longer incubation period than patients with malignancy. The groups had similar responses to surgery.

Functionalization of SF/HAP Scaffold with GO-PEI-miRNA inhibitor Complexes to Enhance Bone Regeneration through Activating Transcription Factor 4.

Evidence indicates that microRNAs (miRNAs) play vital roles in regulating osteogenic differentiation and bone formation. Methods: Here, we show that a polyethyleneimine (PEI)-functionalized graphene oxide (GO) complex efficiently loaded with the miR-214 inhibitor is assembled into silk fibroin/hydroxyapatite (SF/HAP) scaffolds that spatially control the release of the miR-214 inhibitor. Results: SF/HAP/GO scaffolds with nanosized GO show high mechanical strength, and their hierarchical microporous structures promote cell adhesion and growth. The SF/HAP/GO-PEI scaffolds loaded with mir-214 inhibitor (SF/HAP/GPM) were tested for their ability to enhance osteogenic differentiation by inhibiting the expression of miR-214 while inversely increasing the expression of activating transcription factor 4 (ATF4) and activating the Akt and ERK1/2 signaling pathways in mouse osteoblastic cells (MC3T3-E1) in vitro. Similarly, the scaffolds activated the osteoblastic activity of endogenous osteoblast cells to repair critical-sized bone defects in rats without the need for loading osteoblast cells. Conclusion: This technology is used to increase osteogenic differentiation and mineralized bone formation in bone defects, which helps to achieve cell-free scaffold-based miRNA-inhibitor therapy for bone tissue engineering.

Case History Report: Cone Beam Computed Tomography for Implant Insertion Guidance in the Presence of a Dense Bone Island.

This article describes the use of cone beam computed tomography (CBCT) to diagnose a dense bone island (DBI) to facilitate implant insertion guidance in a patient followed up for 4 years. Suitable image-directed preplanning and periodic review by CBCT scanning is recommended when a jaw DBI is encountered in treatment planning for implant placement.

[MINI TITANIUM PLATE FOR TREATMENT OF INTRACAPSULAR CONDYLAR FRACTURES].

OBJECTIVE: To investigate the effectiveness of mini titanium plate for the treatment of intracapsular condylar fractures-type A. METHODS: Between March 2013 and July 2015, 22 cases (26 sides) of intracapsular condylar fractures-type A were treated with mini titanium plate through anterior auricular approach. There were 13 males and 9 females, aged from 16 to 32 years (mean, 22.7 years). The disease causes were traffic accident injury in 17 cases, falling injury in 4 cases, and heavy impact injury in 1 case. Five cases had intracapsular condylar fractures-type A only, and the other cases were accompanied with fractures of mandible, maxillary, or other part of jaw. All patients had different degrees of limitation of opening mouth, occlusal disorder, and joint pain, and the maximum opening was 5-16 mm (mean, 8.6 mm). All patients received surgical treatment within 2 to 9 days after injury (mean, 4 days). The clinical dysfunction index (DI) of Helkimo index was used to evaluate the mandibular motor function postoperatively. According to the 4 basic criterion of cure about mandibular condylar fractures by the international consensus conference in 1999, and maximal mouth opening by HE Dongmei et al., the surgical treatment effectiveness was evaluated. RESULTS: All wounds healed at stage I, with no infection or other complications. All 22 cases were followed up 5-8 months (mean, 6 months). At 1 week after operation, the coronal spiral CT and three-dimensional reconstruction showed that contraposition of fractures was good, and the condyles located in the articular fossa. At 6 months after operation, the maximum opening was 33-42 mm (mean, 35.7 mm). After operation, 3 cases showed the mandible deflected to the affected side when opening, and limited lateral motion. According to the DI evaluation method in Helkimo index, there were 7 sides of DI grade 0, 18 sides of DI grade I, and 1 side of DI grade II. Based on surgical treatment effect of intracapsular condylar fractures-type A, occlusion recovery was obtained in 19 cases (86.36%), maximum opening degree of ≥ 35 mm in 20 cases (90.91%), no symptoms of joint injury in 19 cases (86.36%), and no serious postoperative complications in 22 cases (100%); 17 cases (77.27%) were in accordance with the above 4 items. CONCLUSION: Mini titanium plate is one of the most effective approaches to treat intracapsular condylar fractures-type A.

Osteomyelitis of Maxilla in Infantile With Periorbital Cellulitis: A Case Report.

Infantile osteomyelitis (IO) is an uncommon and life-threatening disease that can be misdiagnosed. Early diagnosis and treatment can reduce the incidence of sequel. In this case report, we present a 25-day-old male infant with apparent edema in the entire left periorbital region. Intraorally, the edema occurred in the mucosa of the upper left alveolar region, and 2 draining fistulas with exuded yellow-white pus were present in the left alveolar region. The patient received constant monitoring after admission, and was diagnosed as IO of the maxilla with periorbital cellulitis and sepsis. He also received incision and drainage and anti-inflammatory treatment. After discharge, the patient was followed up for 3 months by phone call, but no recurrence of symptoms was found. Infantile osteomyelitis is rare in clinic. This case report reminds us of the significance of IO and provides some implications on its diagnosis and treatment.

Antigen-extracted xenogeneic cancellous bone graft with recombinant human bone morphogenetic protein-2 enhances bone regeneration in repair of mandibular defect in rabbits.

The effects of a large-piece of xenogeneic bone that was separated from healthy pigs as a scaffold for the repair of a mandibular defect was investigated, and the applicability of antigen-extracted xenogeneic cancellous bone (AXCB) soaked with recombinant human bone morphogenetic protein-2 (rhBMP-2) in bone defect repair was assessed. Mandibular defects were created in 48 New Zealand rabbits, and the animals were randomly divided into four groups, in which the mandibular defects were grafted with AXCB, AXCB soaked with rhBMP-2, and autograft bone, or left blank. An equal number of animals from each group were classified into three time points (4, 8, and 12 weeks) after surgery for gross pathological observation, hematoxylin and eosin (H and E) staining, radiographic examination, and bone density measurement. H and E staining revealed that the area percentage of bone regeneration in the group of the AXCB/rhBMP-2 graft was 27.72 ± 4.68, 53.90 ± 21.92, and 77.35 ± 9.83 at 4 weeks, 8 weeks, and 12 weeks, respectively. These results were better than those of the autogenous bone graft, suggesting that the group of the AXCB/rhBMP-2 graft achieved a good osteogenic effect. With regard to the AXCB graft without rhBMP-2, the area percentage of bone regeneration was only 14.03 ± 5.02, 28.49 ± 11.35, and 53.90 ± 21.92. Therefore, the osteogenic effect of the AXCB/rhBMP-2 graft was demonstrated to have the best effect. In the group of the AXCB/rhBMP-2 graft, the area percentage of bone regeneration increased, and the implanted materials were gradually degraded and replaced by autogenous bone regeneration over time. We conclude that the AXCB graft soaked with rhBMP-2 showed good osteogenic effect in the repair of bone defects and good biocompatibility. AXCB serves as a good carrier of rhBMP-2, which promotes bone formation.

Role of retention of the condylar cartilage in open treatment of intracapsular condylar fractures in growing goats: three-dimensional computed tomographic analysis.

Our aim was to investigate the role of retention of the condylar cartilage in open reduction and internal fixation (ORIF) of intracapsular condylar fractures (ICFs) in growing goats by three-dimensional computed tomographic (CT) analysis. Twelve goats 6 months old were randomly divided into three groups. ICFs were created bilaterally in mandibular condyles and treated with ORIF. On the one side (n=4) the condylar cartilage was removed, and on the other side (n=4) it was retained. Condyles in the control group (n=4) were untouched. CT scans were taken immediately postoperatively, and 3 and 6 months later. The heights of the rami among the three groups were compared, There were significant reductions in the height of rami in the group from which the cartilage had been removed 3 and 6 months postoperatively compared with controls, but no significant differences between control group and the group in which it had been retained. We conclude that retaining condylar cartilage in the ORIF for ICF of growing goats has no harmful effect on condylar growth, but removal can limit growth.