Perforated Hydrogels Consisting of Cholesterol-Bearing Pullulan (CHP) Nanogels: A Newly Designed Scaffold for Bone Regeneration Induced by RANKL-Binding Peptides and BMP-2.

The receptor activator of NF-κB ligand (RANKL)-binding peptide, OP3-4, is known to stimulate bone morphogenetic protein (BMP)-2-induced bone formation, but peptides tend to aggregate and lose their bioactivity. Cholesterol-bearing pullulan (CHP) nanogel scaffold has been shown to prevent aggregation of peptides and to allow their sustained release and activity; however, the appropriate design of CHP nanogels to conduct local bone formation needs to be developed. In the present study, we investigated the osteoconductive capacity of a newly synthesized CHP nanogel, CHPA using OP3-4 and BMP-2. We also clarified the difference between perforated and nonperforated CHPA impregnated with the two signaling molecules. Thirty-six, five-week-old male BALB/c mice were used for the calvarial defect model. The mice were euthanized at 6 weeks postoperatively. A higher cortical bone mineral content and bone formation rate were observed in the perforated scaffold in comparison to the nonperforated scaffold, especially in the OP3-4/BMP-2 combination group. The degradation rate of scaffold material in the perforated OP3-4/BMP-2 combination group was lower than that in the nonperforated group. These data suggest that perforated CHPA nanogel could lead to local bone formation induced by OP3-4 and BMP-2 and clarified the appropriate degradation rate for inducing local bone formation when CHPA nanogels are designed to be perforated.

Management of a Brain Abscess Presumably Caused by Radiation Osteomyelitis of the Mandible.

In this clinical report, we present the management of a brain abscess that was presumed to be caused by radiation osteomyelitis of the mandible. The patient underwent chemoradiotherapy for oropharyngeal carcinoma on the left side at the Department of Otolaryngology of our hospital in 2000. Local recurrence or metastasis did not occur post-treatment. In January 2009, the patient was diagnosed with radiation osteomyelitis of the mandible on the left side, complicated by a pathologic fracture. In July 2011, numbness occurred in the left upper extremity and the patient was transferred to the emergency center of our hospital. A computed tomography scan showed a tumor lesion in the brain that was diagnosed as a brain abscess by magnetic resonance imaging. Neurosurgeons performed burr hole drainage of the abscess, followed by administration of antibiotics. Although impaired fine movements of the left hand remain, progress has been relatively favorable with no recurrence of osteomyelitis or brain abscess post-surgery.

Surgical Management of Duplication of the Pituitary Gland-Plus Syndrome With Epignathus, Cleft Palate, Duplication of Mandible, and Lobulated Tongue.

A 1-day-old male infant was referred to our department for evaluation of multiple malformations in his oral cavity. He was diagnosed duplication of the pituitary gland-plus syndrome with epignathus, cleft palate, duplication of the mandible, and a lobulated tongue. A thumb-sized mass lesion was visible on the hard palate. The duplicated mandible and lower lip was fused at the midline. The alveolar ridge was protruding through a wide-cleft soft palate involving the uvula. Further examination showed a lobulated tongue, which was seen behind the duplicated part of the mandible. Five days after birth, tracheotomy and epignathus resection were performed. At 7 months of age, the excess tissue of the duplicated mandible was resected at the area of adhesion on the lingual side, and the duplicated tongue and lip were reconstructed. A palatoplasty was performed at 20 months of age. Thereafter, the patient's progress was uneventful, with no abnormality in swallowing. No recurrence of epignathus has been observed during 2 years of follow-up.

Six1 is required for mouse dental follicle cell and human periodontal ligament-derived cell proliferation.

The periodontal ligament (PDL) is a connective tissue that attaches the tooth cementum to the alveolar bone and is derived from dental follicle cells (DFCs). The DFCs form fibroblasts, osteoblasts, cementoblasts, and PDL stem cells (PDLSCs). We previously reported homeobox transcription factor Six1 expression in mouse DFCs. However, the role of Six1 in periodontal tissue development is largely unknown. In this study, we analyzed SIX1 expression in mouse periodontal tissue cells during postnatal development and adulthood. We also addressed the role of SIX1 in mouse periodontium development and in human cultured PDL-derived cells (PDLCs). In mouse development, SIX1 production was abundant in DFCs and PDL cells by 2 weeks, but it was greatly diminished in the PDL at 4 weeks and in adults. Although the SIX1-positive cell distribution was sparse in the adult PDL, SIX1-positive cells were observed with low expression levels. We used 5-ethynyl-2'-deoxyuridine (EdU) for cell labeling to reveal numerous EdU/SIX1-double positive cells at 2 weeks; however, a few EdU-positive cells remained at 4 weeks. The proportion of DFCs that incorporated EdU was significantly lower in Six1-deficient mice compared with wild-type mice at E18.5. In human PDLCs, SIX1 was intensely expressed, and SIX1-knockdown using siRNA reduced proliferating PDLCs. Our results suggest that SIX1 is a key proliferation regulator in mouse DFCs and human PDLCs, which provides novel insight into Six family gene function in mammals.

Relationship Between Oral Perception and Habitual Chewing Side for Bare Bone Graft With Dental Implants After Mandibular Reconstruction.

OBJECTIVE: The purpose of this study was to investigate the relationship between habitual chewing side and perception of the oral mucosa following reconstruction with dental implants. STUDY DESIGN: Five patients comprised 2 males and 3 females, with ameloblastoma in 2 patients, odontogenic myxoma in 2 patients, and oral squamous cell carcinoma in 1 patient. They were treated using mandibular reconstruction with bare bone graft after segmental resection of the mandible. Perception (tactile, warm, and cold) was measured at 8 points (chin, lower lip, gingiva, and lateral edge of the tongue, bilaterally). Habitual chewing side was evaluated using a computerized index, the first chewing cycle, and a question on chewing. RESULTS: Perception on resected sides was improved at all measurement points for tactile and cold sensitive evaluation, although sensitivities on the resected side remained below the normal range. In the relationship between habitual chewing side and implanted prostheses in reconstructed bone, the chewing side was the resected side in 2 of the 5 patients. When those 2 patients underwent prosthesis implantation after removal of denture, the chewing side changed from the nonresected side to the resected side. Implant prostheses on resected side were suggested to contribute to masticatory function. Perception in those patients was incomplete but was improved compared with other patients. When prosthesis implantation is performed on the reconstructed side, the resected side may become the habitual chewing side. CONCLUSIONS: Recovery of perception can influence acquisition of the habitual chewing side.

Short Lingual Osteotomy Using a Piezosurgery Ultrasonic Bone-Cutting Device During Sagittal Split Ramus Osteotomy.

Short lingual osteotomy is a useful method for the performance of sagittal split ramus osteotomy involving interference between the proximal and distal bone fragments when lateral differences exist in the setback distance. However, this procedure occasionally results in abnormal fracture and nerve injury; expert surgical skill is thus required. We herein describe a novel technique involving the use of an ultrasonic bone-cutting device (Piezosurgery; Mectron Medical Technology, Carasco, Italy) for vertical osteotomy posterior to the mandibular foramen. Successful short lingual osteotomy was performed using this technique with avoidance of abnormal fracture and neurovascular bundle damage.

A novel technique for preventing skin pressure sores using a rubber tube during surgical treatment of mandibular condyle fractures.

Craniofacial surgery occasionally results in sores and necrosis of the facial skin because of pressure from surgical instruments. During surgical treatment of mandibular condylar process fractures, the main mandibular fragment is routinely retracted downward using a wire to achieve a satisfactory anatomic reduction. This procedure may injure the facial skin. This potential complication is easily overlooked by medical staff, but it is easily preventable. We herein describe a method of using a rubber tube to avoid causing pressure sores of the facial skin during surgical treatment of mandibular condylar process fractures.

Clinical presentation of epignathus teratoma with cleft palate; and duplication of cranial base, tongue, mandible, and pituitary gland.

A 2-day-old girl was diagnosed with an oral epignathus teratoma and an uncommon combination of orofacial malformations including cleft palate; tongue, mandible, cranial base, cervical vertebrae, lower lip, and pituitary gland duplications; and fistula of the glabella and lower lip. Computed tomography revealed that the mass within the nasal cavity had tooth-like calcifications and protruded into the nasopharynx and oral cavity. It was implanted on the anterior wall of the body of the sphenoid bone and was accompanied with mandibular duplication. Magnetic resonance imaging detected duplication of the pituitary gland and confirmed the absence of intracranial communication of the nasopharyngeal mass. The teratoma did not cause respiratory obstruction; however, the patient required continuous nasogastric tube feeding. Usually, an epignathus teratoma is associated with few midline defects and can be corrected with multiple interventions at different time points. The current study describes the surgical procedure comprising excision of the tumor along with reconstructive surgeries of the mandible, tongue, and fistulae undertaken when the infant reached 7 months of age. The cleft palate was repaired at 18 months of age using the Kaplan buccal flap method. Histopathologic examination confirmed a grade 0 teratoma covered with keratinized skin and containing pilosebaceous and sweat glands, adipose tissue, and smooth muscle. The long-term success of this intervention was determined at the follow-up examination conducted at 3 years of age, with no signs of the teratoma recurrence observed.

Evaluation of mandibular hypoplasia in patients with hemifacial microsomia: a comparison between panoramic radiography and three-dimensional computed tomography.

OBJECTIVE: To compare the accuracy of three-dimensional computed tomography (3D-CT) and panoramic radiography in the evaluation of mandibular hypoplasia in patients with hemifacial microsomia (HFM). DESIGN: Retrospective study of imaging data. Setting : Images selected from the archives of the University of Tokyo Hospital. SUBJECTS: Twenty patients with unilateral HFM who had undergone both panoramic radiography and 3D-CT in the same period. METHOD: Mandibular deformities were classified according to the Pruzansky classification; eight patients had Grade I deformity and 12 patients had Grade II deformity. Ramus heights were measured on both panoramic radiographs and 3D-CT. MAIN OUTCOME MEASURES: Magnification in panoramic radiographs and extent of mandibular asymmetry as estimated by the affected/unaffected side ratio based on two methods were examined. The Pearson product-moment correlation coefficient was used to estimate correlations between parameters. RESULTS: The magnification of ramus heights on panoramic radiographs showed large variations in Grade II patients. The affected/unaffected side ratio estimated by the two methods showed a strong correlation in Grade I patients (correlation coefficient 0.99; p < .0001). Conversely, a weak correlation was seen in Grade II patients (correlation coefficient 0.77; p  =  .0036), and affected/unaffected side ratios from panoramic radiographs were both over- and underestimated. CONCLUSIONS: The accuracy of evaluation using panoramic radiography was fairly reliable in Grade I patients. Conversely, accuracy was poor in Grade II patients, and evaluation using 3D-CT seems preferable. The combination of two methods with careful consideration is recommended for clinical applications.

Postoperative evaluation of bone bridge after alveolar bone graft with cortical bone lining technique.

OBJECTIVE: For alveolar bone grafting (ABG), we have been performing surgery using a technique in which a cortical bone lining iliac endplate is applied to the anterior nasal aperture inferior margin. Herein, we used conventional and cortical bone lining techniques to examine the postoperative bone-bridge morphology after ABG. STUDY DESIGN: Fifty-five unilateral patients who underwent ABG at our clinic from October 2012 to March 2019 were included. We used postoperative CT data to compare the labiolingual width of the grafted bone and anterior-posterior and vertical shapes of the nasal aperture inferior margin with respect to the ungrafted side. RESULTS: The cortical bone lining technique was superior to the conventional method. The cortical bone lining technique showed good results regardless of alveolar cleft width or oral-nasal fistula. Also, tooth movement into the grafted area was involved in maintaining the residual graft bone; however, the cortical bone lining technique had better results. CONCLUSIONS: The cortical bone lining technique allows for the physical closure of nasolateral mucosal fistulas when it is technically difficult, and it can apply sufficient pressure to the bone marrow cancellous bone filling over the cortical plate bone. Our results illustrate the effectiveness of the cortical bone lining technique.

Long-term dental outcomes in patients with fibrodysplasia ossificans progressiva: a report of three cases of tooth extraction.

Fibrodysplasia ossificans progressiva (FOP) is an extremely rare autosomal dominant disorder characterized by congenital skeletal malformation and progressive heterotopic ossification. In the oral and maxillofacial region, deformity of the temporomandibular joint is a common feature of FOP, as well as restricted mouth opening derived from heterotopic ossification in the masticatory muscles. Since surgical procedures are generally not recommended because of the risk of flare-ups and increased heterotopic ossification, reports of tooth extractions and their outcomes in patients with FOP are limited. The present article reports the long-term oral outcomes of three Japanese patients with FOP, in whom the teeth were deliberately extracted to avoid the risk of oral inflammation causing further heterotopic ossification. The extractions were conducted under local or general anesthesia, and healing of sockets was nonproblematic with the formation of new bone. Undesirable events, including progression of heterotopic ossification in the oral and maxillofacial region and further restriction of mouth opening, were not apparent. The extractions also alleviated the existing inflammation, contributing to maintaining their oral hygiene. These cases suggest that deliberate planning and judicious surgery could induce favorable healing after tooth extractions in patients with FOP, leading to long-term stability of their oral health status.

Evaluation of patients with oral squamous cell carcinoma treated by radical irradiation with mold radiotherapy using a customized device: a retrospective clinical study.

BACKGROUND: It is very important to determine the indication of mold radiotherapy for the radical treatment of oral cancer. We investigated eight patients with oral squamous cell carcinoma who were treated by radical irradiation with mold radiotherapy using a customized device. METHODS: The subject is a case of curable superficial oral cancer of a few millimeters, or cancer of a size that can be cured by the placement of the radiation source. Of the eight patients, six were male and two were female, aged 64-93 years (mean, 78.9 years; median, 73.5 years). The primary sites were the buccal mucosa in three cases, gingiva in two cases, and floor of the mouth, soft palate, and lower lip in one case each. Five cases were in the T1 stage, and the remaining three cases were in T2. With respect to thickness, seven cases were of the superficial type and could not be detected by magnetic resonance imaging or computed tomography, and the remaining case showed a tumor thickness of 7.5 mm. All cases were diagnosed as squamous cell carcinoma by biopsy. Radical irradiation using mold radiotherapy was planned for all eight patients. Irradiation was delivered in 9-10 sessions, with a total dose of 45-50 Gy. RESULTS: Complete response was attained in six of the eight patients and partial response was observed in two patients, requiring additional treatment. CONCLUSION: Since all patients with complete response had superficial cancers, we hypothesized that superficial cancers of the oral cavity with thicknesses of few millimeters could be indicated for mold irradiation. This method can be applied in complicated cases and older patients in whom surgery or chemotherapy may not be feasible. We believe that the results of our clinical studies will be of great help in choosing this method.

The effects of perioperative oral management on perioperative serum albumin levels in patients treated surgically under general anesthesia: A multicenter retrospective analysis in Japan.

ABSTRACT: The purpose of the present study was to investigate the efficacy of perioperative oral managements (POMs) on perioperative nutritional conditions in patients undergoing surgery with general anesthesia. Medical records were retrospectively reviewed and the effects of POMs were investigated based on a large number of cases using a multicenter analysis. The profile of serum albumin levels was assessed and compared between patients with and without POMs using the multivariate analysis. Seventeen Eleven thousand and one hundred sixty patients (4,873 males and 6,287 females) were reviewed. Of these, 2710 patients (24.3%) had undergone POMs. The results of a multivariate analysis revealed the significant positive effect of POMs on perioperative serum albumin level (change between at admission and discharge, (Estimate: 0.022, standard error: 0.012, P < .0001). Patient gender, age, surgical site, performance status, the American Society of Anesthesiologists (ASA) physical status classification, operation time, amount of blood loss, and serum albumin level at admission were also significant predictors. Adjusted multivariate analysis of the effects of POMs on perioperative change of serum albumin level in all subjects reveled the significance of POMs intervention (estimate: 0.022, standard error: 0.012, P < .0001). These results suggest that POMs exerts significant positive effects on perioperative serum albumin levels in patients underwent surgery under general anesthesia.

Maxillofacial reconstruction using custom-made artificial bones fabricated by inkjet printing technology.

Ideally, artificial bones should be dimensionally compatible with deformities, and be biodegradable and osteoconductive; however, there are no artificial bones developed to date that satisfy these requirements. We fabricated novel custom-made artificial bones from alpha-tricalcium phosphate powder using an inkjet printer and implanted them in ten patients with maxillofacial deformities. The artificial bones had dimensional compatibility in all the patients. The operation time was reduced due to minimal need for size adjustment and fixing manipulation. The postsurgical computed tomography analysis detected partial union between the artificial bones and host bone tissues. There were no serious adverse reactions. These findings provide support for further clinical studies of the inkjet-printed custom-made artificial bones.

In situ surface modification on dental composite resin using 2-methacryloyloxyethyl phosphorylcholine polymer for controlling plaque formation.

Composite resins (CRs) are widely used as dental restorative materials for caries treatment. They cause problems of secondary caries since Streptococcus mutans stays in the dental plaque, which the surface exists and produces acidic compounds during metabolism. The dental plaque depositions are induced by the protein adsorption on the surface. Therefore, suppression of protein adsorption on the surface of the CRs is important for inhibiting the formation of plaque and secondary caries. In this study we developed a surface treatment to provide an antibiofouling nature to the CRs by chemical reaction with 2-methacryloyloxyethyl phosphorylcholine (MPC) polymers in the oral cavity during dental treatment. To carry out the photochemical reaction on the remaining polymerizable groups of CRs, we synthesized the MPC polymer with a polymerizable group in the side chain. The MPC polymer could bind on the surfaces of the CRs chemically under dental treatment procedures. The treated surface showed significant resistance to oral protein adsorption and bacterial adhesion even when the surface was brushed with a toothbrush. Thus, we concluded that the photochemical reaction of the MPC polymer with the CRs in the oral cavity was good for making an antibiofouling surface and preventing secondary caries.

Time dependence of multi-ion absorption into human enamel from surface prereacted glass-ionomer (S-PRG) filler eluate.

Ion incorporation into the tooth is expected to be effective for caries prevention. Time-dependent ion incorporation released from surface pre-reacted glass-ionomer (S-PRG) filler eluate into tooth enamel was estimated by using inductively coupled plasma atomic emission spectroscopy (ICP-AES). Al, B, and Sr contents in enamel were increased in a time-dependent manner with immersion in S-PRG eluate. Clear ion incorporation was observed after 1 h of immersion in S-PRG filler eluate. Sr showed remarkable incorporation in enamel -up to 7,900 ppm- after 28 days of immersion. Sr and B incorporation rapidly occurred in S-PRG filler eluate, compared with their single component solutions. Simultaneous incorporation of cations and anions from S-PRG eluate occurred under balanced charge and may assist in rapid ion incorporation. Thus, various useful ions could be effectively incorporated into tooth enamel by applying S-PRG filler or its eluate; a bioactive effect can be expected.

A modified preauricular and transmandibular approach for surgical management of osteosarcoma of the mandibular condyle within the masticator space and infratemporal fossa: a case report.

BACKGROUND: Osteosarcomas of the head and neck region are rare entities that comprise < 10% of all osteosarcomas. Multimodality treatment of patients with osteosarcoma is well-established for osteosarcoma in long bones, and the benefits of chemotherapy in long bones are clearly known. However, there is no consensus regarding the effects of chemotherapy in cases of head and neck osteosarcoma. The prognostic factor for head and neck osteosarcoma is complete tumor resection with negative margin, which is a radical surgery. However, a clear margin may be difficult to achieve in the head and neck region. CASE PRESENTATION: We present a case of a 69-year-old Japanese woman who developed osteosarcoma of the condyle within the masticator space and infratemporal fossa, which was treated with radical surgery using a modified preauricular and transmandibular approach. Although we recommended adjuvant treatment after surgery, the patient refused this treatment. There was no evidence of local recurrence or distant metastasis through 30 months of follow-up. CONCLUSIONS: Our modified preauricular and transmandibular approach allowed access to the masticator space and infratemporal fossa, thereby increasing complete resection of the tumor and resulting in minimal functional and cosmetic deficits.

Clinical application of artificial bone in the maxillofacial region.

Hard tissue reconstruction is very useful for bony defects of the maxillofacial region. Autogenous bone, allogeneic bone, and artificial bone have been used to reconstruct maxillofacial bone; however, the use of autogenous bone involves high surgical invasiveness because of the need to harvest the bone. The use of allogeneic bone is associated with infections, raises ethical concerns, and is not widely used in Japan. Artificial bone has several advantages, including no need for bone harvesting, excellent biocompatibility, and a relatively easy surgical procedure. Use of artificial bone avoids the much greater invasiveness of harvesting bone, and several types of artificial bone have been developed. Design requirements for artificial bone include surgical manipulability, structural compatibility with the defective area, support properties, and the ability to induce bone regeneration; however, no artificial bone meeting all these requirements has yet been developed. Artificial bone is used in many patients in our medical center, and we have been active in developing the next generation of artificial bone with better properties. In this article, we present a case history and discuss the future development of artificial bone for use in maxillofacial reconstruction.

[Clinical application of bone regeneration by in vivo tissue engineering].

With regard to the graft materials, cortical bone block, vascularized bone flap and particulate cancellous bone and marrow (PCBM) have been used for the reconstruction of maxillofacial skeleton. Needless to say, the aim of cortical bone block and vascularized bone flap transfer is the transplantation of bony tissue of its own. On the other hand, the main objective of PCBM grafting is the transplant of osteogenic stem cells derived from uncommitted marrow mesenchymal cells. After PCBM grafting, active new bone formation occurs from osteogenic stem cells followed by bone remodeling and replacement of host bone. This process means that PCBM grafting is the method of bone regeneration that is based on in vivo tissue engineering. In this paper, clinical application of PCBM grafting for the reconstruction of maxillofacial skeleton is introduced by showing the repair of maxillary bony defect of cleft lip and palate patients, alveolar ridge augmentation and the reconstruction of large mandibular segmental defects.

In-hospital surgical treatment for haemorrhage after aesthetic mandibular osteotomy performed as an office-based day surgery: A case report.

In East Asia, a square face is considered unattractive, and mandibular contouring surgery is commonly used to give a smooth contour to the lower jaw. Mandibular contouring surgery occasionally involves not only osteotomy of the mandibular angle but also resection of the masseter muscle via an intraoral approach. This type of mandibular contouring surgery poses a risk of injury to the premasseteric branch of the facial artery and massive haemorrhage. Here we report a patient who presented to our hospital with severe haemorrhage, swelling and airway constriction after bilateral mandibular angle and plane osteotomy with resection of the masseter muscle performed elsewhere as an office-based day surgery. The swelling and haemorrhage were treated successfully with emergency bilateral ligation of the facial artery and vein under general anaesthesia. We concluded that the haemorrhage was caused by rupture of the premasseteric branch of the facial artery during the resection of the masseter muscle in a day surgery.