Various bone grafting materials are used for bone augmentation procedures in the field of oral-maxillofacial surgery. Knowledge of biomaterial characteristics is crucial in order to choose the appropriate materials for each clinical case. The purpose of the present study was to investigate not only the conventional method of comparison of osteogenic potential of different bone grafting materials, but also evaluate the macrophage behavior and the potential as carriers of growth factors in vitro.

　Cell attachment/proliferation on bone grafting materials and the gene expressions of cell differentiation markers were investigated in the human leukemia monocytic cell line THP-1-derived macrophages and mouse stromal ST-2 cells, when cultured on the three different grafting materials of 1) demineralized freeze-dried bone allografts (DFDBA)(DBX^®, Synthes Inc. USA), 2) deproteinized bovine bone mineral (DBBM)(Bio-Oss^®, Geistlich Pharma AG, Switzerland), and 3) biphasic calcium phosphate (BCP)(Maxresorb^® granules, Botiss AG, Germany). Furthermore, bone morphogenetic protein-2 (BMP-2) adsorption, release kinetics, and osteoblastic activities of BMP-2-loaded materials were evaluated.

　Higher cell attachment/proliferation potentials in both THP-1-derived macrophages and ST-2 cells were observed when cultured on BCP. Interestingly, DFDBA showed high TNF-α expression with a strong tendency toward M1 phenotypes, whereas BCP showed high IL-10 expression in macrophages and was polarized toward M2 phenotypes. Furthermore, DFDBA significantly increased mRNA levels of bone sialoprotein (BSP) when compared to the other materials in ST-2 cells. DBBM adsorbed a higher amount of BMP-2 when compared with the other materials while the DFDBA released BMP-2 faster. DFDBA showed higher osteopromotive potential including higher mRNA levels of ALP and BSP when used in combination with BMP-2, compared to BMP-2 alone.

　From this limited study, BCP showed superior cytocompatibility. Nevertheless, DFDBA might be a good option when focusing on higher osteopromotive potential, and for use as a BMP-2 carrier.

Medical leeches have been an effective therapy for any free flap suffering from impaired venous circulation. We report a summary of medical leech treatment for flap congestion in nine out of 515 cases of free flap transfer that were performed in our department from 2009 to 2019. Concerning the types of the free flaps, three cases consisted of rectus abdominis musculocutaneous flap and scapular osteocutaneous flap, two cases were antero-lateral thigh flap, and one case was forearm flap. Improvement of flap congestion was observed in seven of the nine cases using medical leeches. These seven cases included all four cases after venous re-anastomosis, and three of the five cases in which no thrombus in the anastomosis of the vein was observed. With respect to flap survival rate, there were no statistically significant differences in postoperative flap congestion confirmation time, the period of medical leech use and the number of medical leeches used. The improvement of flap congestion without surgical treatment was beneficial for patients, suggesting that medical leeches may be a useful treatment for congestive flaps.

We report herein a case of Schwann cell hamartoma with surficial multinodular tactile corpusclelike bodies on the dorsum of the tongue in a 22-year-old female. The patient had noticed a tumorous swelling with irregular surface on the right side of tongue since her childhood. She visited our department in the hope of resolving the swelling in 2011. Subtotal resection was performed to achieve cosmetic reduction of the lesion. The surgical specimen showed proliferating Schwann cells underneath the mucosal epithelium, which were localized in the lamina propria with no copsulation. The proliferating cells showed positive immunoreactivity for S-100 and SOX10. There was no cellular nor nuclear atypism. These findings corresponded to Schwann cell hamartoma. There has been no growth of the lesion in the seven years after operation.

Carbamazepine is widely used as an anticonvulsant or antipsychotic agent. As a sodium channel blocker, it provides therapeutic benefit in patients with trigeminal neuralgia and may be used for the differential diagnosis of pain. We report a case of marked thrombocytopenia during carbamazepine administration in a patient with idiopathic trigeminal neuralgia. A 37-year-old woman presented with acute intermittent electric shock-like pain when pressure was applied to the left mental foramen, or when cold air was applied to the left lower lip. We observed no sign of dental infection. No obvious vascular contact in intracranial lesions or the trigeminal nerve root entry area was observed in MR imaging. We initiated carbamazepine (200 mg/day) therapy for a clinical diagnosis of idiopathic left trigeminal neuralgia (tertiary branch). The patient developed petechial hemorrhages on the face, neck, and extremities 16 days after carbamazepine administration, and blood test results revealed significant thrombocytopenia (her platelet count was remarkably low, at 1.5×10⁴ /μ L). We suspected carbamazepine-induced thrombocytopenia. The medication was discontinued, resulting in a gradual disappearance of the petechial hemorrhages and recovery of the platelet count to 23.7×10⁴ /μ L six days after carbamazepine cessation. Subsequently the left-sided mental foramen pain was controlled with pregabalin administration (150 mg/day), without any adverse effects.

Delanian et al. reported the efficacy of pentoxifylline-tocopherol-clodronate (PENTOCLO) treatment for osteoradionecrosis (ORN) of the mandible in 2011. Spontaneous sequestration and epithelialization of the mandibular lesion are induced by this method. We report a case of osteoradionecrosis of the mandible which responded to treatment with PENTOCLO. A 60-year-old man was referred to our department with persistent mandibular ORN after definitive chemoradiotherapy for oropharyngeal carcinoma (T2N0M0). Periodontitis of the right second molar caused ORN, followed by pathological fracture. PENTOCLO treatment was started following 4-week antibiotic therapy. The sequestrum spontaneously separated with mucosal epithelialization two months after the treatment started. The second molar was removed at 11 months because of its increasing mobility. The extraction socket had epithelized and computed tomography (CT) showed that the pathological fracture had healed. No adverse events occurred during this treatment course. PENTOCLO may be an organpreserving treatment option for ORN of the mandible.

An osteoma is a benign osteogenic tumor arising from the proliferation of mature bone. They have been reported to occur primarily in the mandible in the oral and maxillofacial region. No previous report has described a large bilateral osteoma with wing-like form arising from the mandibular ramus. We report herein a case of bilateral osteoma of atypical form occurring in the mandible. A girl of 15 years of age presented with the chief complaint of swelling and food impaction in the left side of the oral floor. Computer tomography revealed a bone-like structure extending from the inside surface of the left side mandible to the ipsilateral oral floor. In addition, another bone-like mass was shown inside the right side mandibular ramus. Both structures presented wing-like characteristic forms. A clinical diagnosis of bilateral osteoma of the mandible was made, and we performed extirpation of the tumor from both sides under general anesthesia. Pathological findings showed that the left side mass was comprised of compacted bone alone and the right side mass contained both compacted bone and cancellous bone. In conjunction with imaging tests, the masses were both diagnosed as osteoma. In the 12 months following the surgery, there has been no recurrence in the left side, whereas a new bone formation was recognized in the right side surgical site.

Ductal papilloma is an extremely rare benign tumor characterized by localized papillary growth in the salivary ducts, and was previously divided into three tumor types: inverted ductal papilloma, intraductal papilloma, and papillary salivary gland adenoma. In the latest classification (2017), inverted ductal papilloma and intraductal papilloma are recognized as subtypes of ductal papilloma. Herein we report a case of inverted ductal papilloma presenting a mucocele-like mass in the buccal mucosa. The patient was a 63-year-old man. He was referred to our department for close inspection and treatment. An elastic, moderately soft, movable, and incompressible mass of about 5 mm was palpated just below the left buccal mucosa. An excisional biopsy was performed under local anesthesia. Histologically, squamous-like cells and basal cell-like cells showed alveolar-like and papillary-like proliferation inward, contiguous with coated squamous cells. The immunohistochemical stainings were CK7 (+), CK5/6 (+), p63 (+), α-SMA (-), p53 (+), and Ki67 (luminal cells 1.29％, non-luminal cells 5.53%). A diagnosis of inverted ductal papilloma was made. HPV DNA testing returned negative. The lesion was totally removed with no remaining lesion noted in surrounding tissues. In the four years since the operation there has been no recurrence and the patient is doing well.

Crohn’s disease (CD) is a granulomatous inflammatory disorder with no known cause. CD is categorized as an inflammatory bowel disease, with the main symptom being colitis. Recognised oral symptoms include aphthous stomatitis and granulomatous cheilitis. We describe a case of CD in a 14-year-old boy who presented with swollen lips. Our examination revealed that he had no abdominal symptoms, but he had additional oral symptoms such as gingivitis, mucosal tag, an ulcer and cobblestone appearance mucosa. Eosinophilic granuloma and gingivitis were suspected. Administration of an anti-allergic drug and periodontal treatment were commenced; however, his symptoms didn’t change. We obtained information that he had had hemorrhoids in the past, indicating a diagnosis of CD. An upper gastrointestinal endoscopy and colonoscopy were performed, and aphthous and ulcerative lesions were found at the rectum and a biopsy was done. Epithelioid cell granuloma (ECG) was detected from the specimen and a final diagnosis of CD was made. The swollen gingiva didn’t respond to treatment. It was excised and ECG was also detected in it. He was given mesalazin and prednisolone, but the oral symptoms remained unchanged and fecal occult blood test (FOBT) remained positive. Adding adalimumab to his medication improved the oral symptoms and the FOBT became negative.

Lichen planus is a common chronic inflammatory disease that affects the skin and mucous membranes, including the oral mucosa, whereas lichen planus pemphigoides is a rare disease. A 74-year-old woman who developed blistering and inflammation of the oral mucosa after the appearance of skin lesions was referred to our hospital for consultation. We examined her serum antibody titer, performed histological and immunohistochemical examinations of the oral mucosa, and consulted a dermatologist. The patient was ultimately diagnosed with lichen planus pemphigoides. After treatment, the blisters in the oral mucosa disappeared. Careful follow-up continues to this today.

Erdheim-Chester Disease (ECD) is a rare histiocytic tumor. The disease is characterized by the symptom of bone pain of the whole body. We report a case of BRAF V600E-positive ECD related tumor of the maxilla. A 55-year-old woman was referred to our department because of pain and swelling in the maxilla. X-ray photo examination showed no clear abnormality; however, PET-CT and a bone scintigraphy showed an abnormal accumulation. Biopsy yielded a diagnosis of an ECD-related tumor. After diagnosis, we conducted additional PCR and immunostaining examinations, and a result of gene mutation in BRAF was obtained. In 2017, the FDA approved Vemurafenib (BRAF-inhibitor) for ECD patients. In the future, we will have more opportunities to treat ECD patients, so it is suggested that not only biopsy but also the genetic analysis and the immunostaining of BRAF V600E are important for adequate treatment.

Myopericytoma is a benign tumor characterized by a perivascular proliferation of myoid differentiating oval spindle-shaped pericytic cells, and it is rarely found in the oral cavity. We report a case of myopericytoma in the floor of mouth. A 66-year-old female was referred to our hospital with the chief complaint of a tumorous lesion of the left side of the floor of mouth. Physical examination revealed a movable, elastic-hard and painless mass. CT examinations showed the mass measuring 23 × 11 mm in the floor of mouth. Histological findings from an incisional biopsy suggested a benign tumor with myoid differentiation. A surgical excision was carried out under general anesthesia. A histopathological diagnosis of myopericytoma was made. No evidence of recurrence was observed during the year and a half following surgery.

Spindle cell lipoma is a rare subtype of lipoma in the oral cavity. Although simple lipoma is easily diagnosed by MRI, it is sometimes difficult to distinguish spindle cell lipoma from liposarcoma due to its similar MRI appearance. A 76-year-old man was referred to our department complaining of a painless mass at the right margin of his tongue. A 10 mm diameter spherical tumor was located under a normal submucosa. MRI revealed a heterogeneous tumorous lesion at the right margin of the tongue in T1- and T2-weighted images. Although lipoma was most highly suspected, liposarcoma was also considered due to the MRI findings. Thus, the tumor was resected with a safety margin. Histopathologically, the tumor possessed a capsule composed of mature adipocytes and spindle cells without muscle tissue. Immunohistochemically, the spindle cells showed S-100 protein-negative and CD34-positive. The lesion was diagnosed as spindle cell lipoma. There has been no recurrence during the 1-year follow-up term.

Meningioma is a brain tumor arising from the meninges, which is extremely rare extracranial. We report an ectopic meningioma of the tongue. A 39-year-old man was referred to our hospital with the chief complaint of a tongue mass. Biopsy revealed a benign tumor, which was surgically removed from the tongue under general anesthesia. Pathological findings showed characteristic spiral growth of tumor cells, and immunostaining was epithelial membrane antigen positive. The pathological diagnosis was a meningioma. After surgery, the whole body was examined and no similar lesion was found. There has been no sign of recurrence as of 2 years after the operation.

This study used dental cone beam computed tomography (CBCT) images to comparatively evaluate the three-dimensional microstructural features of a reconstructed bone bridge based on the bone harvesting site and the presence/absence of artificial bone material, as well as the features of regenerated bone tissue after bone harvesting from mandibular symphysis in secondary alveolar bone grafting (SABG) for patients with cleft lip (with or without cleft palate). Thirty-one patients were divided into three groups in which SABG was performed by autologous bone harvesting from the iliac crest (IC), mandibular symphysis (MS), or MS combined with β-TCP granules (MS+TCP). The microstructural trabecular bone parameters were analyzed using datasets of CBCT images taken prior to and at 12 months following SABG. The microstructural parameters showed differences between IC and MS groups (P<0.05), resulting in greater values of bone volume density (P< 0.05) and an inferior value of TBPf (P= 0.070) in the IC group compared with the MS group. Using MS+TCP or filling β -TCP granules into the donor site significantly improved the reconstructed or regenerated BV/TV and Tb.Th (P<0.05) compared with the group without β-TCP. Microstructural characteristics of the reconstructed bone bridge were dependent on the donor site of bone harvesting; using an absorbable bone conductive material improved bone quality and increased bone volume density. Thus, the application of β -TCP granules as a partial bone alternative together with autologous bone from mandibular symphysis can obtain comparable outcomes in the microstructure of bone bridges to autologous iliac crest SABG.