Collaboration with an infection control team promoted appropriate antibiotic use for third molar extraction at a Japanese hospital.

Oral antibiotic therapy is routinely administered when a third molar (M3) is extracted to prevent infectious complications after surgery. Oral third-generation cephalosporins are frequently used after M3 extraction in Japan but at the expense of an increased risk of antimicrobial resistance. Therefore, the infection control team (ICT) at our institution recommended a reduction in use of these agents after M3 extraction. In this study, we compared the types of antibiotic agents prescribed for patients undergoing M3 extraction before and after this recommendation. We investigated the relationship between type of antibiotic used and the likelihood of infectious complications as well as cost savings in patients who underwent M3 extraction in the 6 months before and after the ICT recommendation in July 2018. There was a marked reduction in use of oral third-generation cephalosporins after M3 extraction (P < 0.0001) and increased use of oral penicillins and first-generation cephalosporins after the ICT recommendation. Moreover, surgical site infection (SSIs) were significantly less common after the ICT recommendation (P = 0.0099); however, the SSI rate was higher in patients who received a third-generation cephalosporin than in those who received penicillin (8.8% vs 0.5%). There was also a significant saving in per-patient antibiotic costs after the ICT recommendation (269.5 ± 282.0 JPY vs 454.7 ± 376.6 JPY; P < 0.0001). These findings suggest that collaboration with an ICT promotes appropriate antibiotic use, decreases the risk of an SSI, and improves the cost-benefit ratio in patients undergoing M3 extraction.

A case of retinoblastoma metastasizing to the mandible and review of literature.

OBJECTIVES: The aim of this case report and review was to determine the characteristics of retinoblastoma. METHODS: One case report was introduced along with previous reports on retinoblastoma metastasizing to the mandible. RESULTS: Sixteen cases from 14 reports were included in this study. Including the present case, 11 of 16 patients died within 8 months. DISCUSSION: Retinoblastoma rarely metastasizes to the mandible. However, metastasis to other organs should be considered, and specialists should be consulted if retinoblastoma metastasis to the mandible is observed. Moreover, it is necessary to follow up patients after multidisciplinary therapy is completed, because subsequent complications of the teeth and jawbones associated with therapy could occur.

Keratocystic odontogenic tumor arising at the mandibular ramus with an impacted tooth: a case report and mimic lesions.

OBJECTIVES: To consider the biologic behaviors of keratocystic odontogenic tumors (KCOTs) and ameloblastomas and dentigerous cysts. METHODS: A 63-year-old Japanese man presented with swelling and discomfort in the left cheek during jaw movement. Examination revealed a multilocular lesion within the mandible extending from the left second premolar to the left mandibular ramus and coronoid process; the lesion contained a deviated impacted tooth. The tumor had expanded beyond the bone and was invading the masseter and medial pterygoid muscles. Marginal mandibulectomy with a free iliac bone graft was performed. RESULTS: No recurrence was observed during a 7-year follow-up. DISCUSSION: The histopathological diagnosis of the lesion showed it was a KCOT. These tumors usually grow within the bone, causing bone expansion. However, this tumor had expanded beyond the bone and invaded surrounding muscles. Thus, KCOTs can, in rare cases, manifest themselves as described here. Evaluating preoperative images and histopathological findings is important to determine the optimal treatment strategy.

Effects of Vertical Movement of the Anterior Nasal Spine on the Maxillary Stability After LeFort I Osteotomy for Pitch Correction.

Few reports have so far evaluated the maxillary stability after LeFort I osteotomy (L-1) for pitch correction. In the current study, the authors assessed the SN-PP (palatal plane) to evaluate the skeletal stability after osteotomy with clockwise or counter-clockwise rotation and investigated the effects of anterior nasal spine (ANS) and posterior nasal spine (PNS) movement on the stability of the SN-PP.The SN-PP and the positions of ANS, PNS, and point A were measured on lateral cephalograms before surgery (T1), immediately after surgery (T2), and more than 1 year after surgery (T3).All measured angle and points were stable in 4 cases of counter-clockwise rotation. In the 16 cases of clockwise rotation, T3-T2 of SN-PP, ANS, and point A was -2.05°, -2.56 mm, and -1.64 mm, when the SN-PP increased more than 4° after osteotomy. When the ANS moved downward more than 3 mm, the ANS and point A relapsed significantly by 2.75 and 2.31 mm, while the SN-PP relapsed 1.61° more than 1 year after surgery.When the SN-PP increased by more than 4° or the ANS moved downward by more than 3 mm, the authors suggest shifting the PNS upward instead of moving the ANS downward.

Application of a real-time three-dimensional navigation system to various oral and maxillofacial surgical procedures.

The aim of this study was to confirm the effectiveness of a real-time three-dimensional navigation system for use during various oral and maxillofacial surgeries. Five surgeries were performed with this real-time three-dimensional navigation system. For mandibular surgery, patients wore acrylic surgical splints when they underwent computed tomography examinations and the operation to maintain the mandibular position. The incidence of complications during and after surgery was assessed. No connection with the nasal cavity or maxillary sinus was observed at the maxilla during the operation. The inferior alveolar nerve was not injured directly, and any paresthesia around the lower lip and mental region had disappeared within several days after the surgery. In both maxillary and mandibular cases, there was no abnormal hemorrhage during or after the operation. Real-time three-dimensional computer-navigated surgery allows minimally invasive, safe procedures to be performed with precision. It results in minimal complications and early recovery.

Risk factors for postoperative hemorrhage after minor oral surgery in patients treated with antithrombotic agents.

It has been proposed that minor oral surgery can be performed safely in patients taking antithrombotic therapy without interrupting treatment; however, there is little evidence-based guidance about how to manage postoperative hemorrhage in patients taking antithrombotics, and few randomized trials that help to inform the risk-benefit ratio of continuing or suspending antithrombotic therapy. The aim of this study was to identify risk factors for postoperative hemorrhage to create a protocol for patients undergoing minor oral surgery with antithrombotic therapy. One hundred and two patients were enrolled, who subsequently underwent 142 minor oral surgical procedures while taking antithrombotic therapy. Demographic details including age and sex, laboratory coagulation investigations, and episodes of postoperative hemorrhage were recorded. The prothrombin time-international normalized ratio (PT-INR) of participants taking warfarin was <3.0 in all cases (mean 1.89 ± standard deviation 0.52; range 1.11-2.82). The activated partial thromboplastin time (APTT) was significantly associated with postoperative hemorrhage, which was significantly increased in patients taking warfarin alone or in combination with an antiplatelet agent compared with an antiplatelet agent alone. In 7 cases, postoperative hemorrhage continued for 4 days and more, requiring additional local hemostatic management. Our findings suggest that minor oral surgery can be performed under antithrombotic therapy without the need of discontinuing the antithrombotic agents. Local hemostatic materials did not suppress postoperative hemorrhage. APTT is a possible prediction factor for postoperative hemorrhage in such patients and, therefore, should be determined prior to minor oral surgery in addition to PT-INR value.

Rapid growing myofibroma of the gingiva: report of a case and review of the literature.

PURPOSE: Myofibroma is a rare benign tumor of myofibroblasts that rarely exhibits rapid enlargement and is misinterpreted as a malignant lesion. The aim of this study was to investigate its growth potential and to evaluate the usefulness of preoperative immunohistochemical study for an accurate diagnosis. MATERIALS AND METHODS: A case of rapidly growing myofibroma of the lower gingiva was analyzed using 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography fused with computed tomography (PET/CT) and immunohistochemical study of Ki-67 and p53. The English-language literature from 1981 to 2012 also was reviewed. RESULTS: An 18F-FDG PET/CT image displayed a high accumulation (maximum standardized uptake value, 14.1) in the lesion. A biopsy specimen showed mitotic activity of spindle-shaped cells, but atypia was not present. The MIB-1 labeling index was 10%, and the p53 test result was negative. The preoperative diagnosis of benign tumor of smooth muscle origin was made from the histopathologic and immunohistochemical features. In a review of 94 cases, tumors involved the mandible (33%), gingiva (23%), tongue (15%), cheek or buccal mucosa (12%), palate (8%), lip (4%), and other areas (5%). Nine cases (9.6%) were described as rapidly enlarging, and 8 cases (8.5%) were suspected of malignancy at initial diagnosis. The preoperative biopsy with immunohistochemical study established an accurate diagnosis in 83% of myofibromas, and no recurrences were reported in these patients. CONCLUSIONS: Careful diagnosis is necessary because these lesions sometimes present clinical and radiologic features that resemble those of malignant tumors. Preoperative immunohistochemical analysis should be performed to avoid misdiagnosis or unnecessary aggressive therapy.

Aspiration pneumonia associated with a double fracture of the mandible.

Aspiration pneumonia is one of the most life-threatening diseases in the elderly. A 73-year-old woman was diagnosed with aspiration pneumonia after a mandibular fracture. Because her persistent aspiration pneumonia was accompanied by a diminished swallowing function that was believed to be due to a double fracture of the mandible, the patient underwent an open reduction while having pneumonia. Her symptoms of aspiration pneumonia improved immediately after the surgery. The hyoid bone was repositioned to its original position, and the movements of the hyoid bone and mandible were recovered after the surgery. In cases in which the medial bone segment of the mandible moves inside because of a double fracture and the movement of the hyoid bone declines, we strongly suggest that an open reduction should be performed as soon as possible to prevent aspiration pneumonia caused by a swallowing dysfunction.

Assessment of migrated foreign bodies in the maxillae by x-ray fluorescence spectrometry.

Two cases of foreign bodies that were incidentally observed on orthopantomographs are reported in this study. The foreign bodies were analyzed using an x-ray fluorescence spectrometer to identify what the migrated foreign bodies were and what migration pathways they had taken. The removed metallic foreign bodies from the maxillae of 2 patients, who were referred to the Department of Dentistry and Oral Surgery of the University of Fukui Hospital, were analyzed using an x-ray fluorescence spectrometer in the Department of Dental and Biomedical Materials Science, Nagasaki University. The major component of foreign body in patient 1 was silver, and that in case 2 was iron. On the basis of the imaging results and the patients' clinical history, the foreign bodies were considered to be caused by iatrogenic migration. Understanding the existence of foreign bodies and their migration pathway into the jaw bone can thus make clinicians more aware of such migrations and can thereby contribute to reducing iatrogenic accidents.

Long-term follow-up after reimplantation of tumorous mandible bone treated with combination of decalcification and lyophilization.

Mandibular resection requires reconstruction, with often unsatisfactory morphofunctional results. Reimplantation of the resected mandible itself is one of ideal solutions to this problem. However, both devitalization of tumor cells involved in resected bone and preservation of osteoinductive activity are required for successful results. Lyophilization appears to enable devitalization of tumor cells, and decalcified bone implants are likely to have osteoinductive potential. Accordingly, we speculated that decalcification and lyophilization of resected bone would be an appropriate method for mandibular reconstruction. However, there is no study on the reimplantation of mandibles treated with these methods to date. The purpose of this study was to estimate the long-term follow-up of reimplanted mandibles treated with decalcification and lyophilization. Presented here are 2 patients of reimplanted mandibles treated by decalcification and lyophilization who were followed up for 8 and 9 years. We observed a good incorporation of the graft in 1 case, but severe absorption in the other. Our results suggest that treatment with decalcification and lyophilization is 1 strategy for reimplantation of the resected bone in mandibular reconstruction, but further study is needed to prevent absorption of the reimplanted bone over the long term.

Enzyme histochemical adaptive responses of the medial pterygoid muscle and two heads of the lateral pterygoid muscle to long-term soft diet feeding in growing rabbits.

The aim of the present study was to investigate the histochemical effects of long-term soft diet in the medial pterygoid muscle as well as the two heads of the lateral pterygoid muscles in growing rabbits. Eleven young rabbits were divided into two groups as solid diet (control group; n = 6) or soft diet (soft-diet group; n = 5) groups. After 6 months, muscle fibers from the medial and the two heads of the lateral pterygoid muscles were histochemically defined. In the medial pterygoid muscle, the percentage of the type 1 fiber cross-sectional area to total area was 10.1 ± 2.4% in the control group and 8.3 ± 3.0% in the soft-diet group, respectively. In the soft-diet group, there was a trend toward an increase in the number of type 2A fibers, and toward a decrease in the numbers of type 2B fibers in comparison with the controls. In the two heads of the lateral pterygoid muscle, the percentage of the type 1 fiber cross-sectional area to total area was 8.4 ± 7.5 and 3.3 ± 2.7%, respectively. Compared to that of the control group, the two heads in the soft-diet group showed a trend toward a decrease in the number of type 2A fibers. In addition, type 2B had a tendency to decrease in the number in the inferior head. In conclusion, this study suggests that long-term soft diet leads to adaptations of the pterygoid muscles. Two heads of the lateral pterygoid muscle revealed different adaptation from jaw-closing muscles under soft-diet conditions.

Mandibular reconstruction using iliac bone and great auricular nerve grafts and oral rehabilitation using osseointegrated implants in a patient with a large ossifying fibroma: a 10-year follow-up study.

Ossifying fibromas are bone-related benign neoplasms that are characterized by well-demarcated lesions composed of fibrocellular tissue and mineralized material with varying appearances. Although small lesions are asymptomatic, they may cause enlargement of the affected jaw and rarely require reconstructive or restorative treatments for aesthetic and functional problems. In this study, we report a 35-year-old woman who underwent multidisciplinary treatment for a large ossifying fibroma of the mandible. A segmental mandibular resection was performed, and immediate reconstruction was performed using iliac bone and great auricular nerve grafts. After consolidation of the grafted bone, oral rehabilitation was fulfilled using osseointegrated implants and a fixed prosthesis. There was no evidence of recurrence ten years after the resection of the tumor. The range of mouth opening and motion of the temporomandibular joint provided a functional mandible. The neurosensory examination revealed the recovery of sensibility of the mental region and pulpal sensitivity of the teeth. The prosthesis was stable, and no clinical or radiographic signs of implant failure were observed. Our results demonstrate that the proper combination of reconstructive and restorative treatments could result in appropriate aesthetic and functional outcomes for a period of ten years.

Reconstruction of the mandible bone by treatment of resected bone with pasteurization.

The results of long-term follow-up for reimplantation of the mandibular bone treated with pasteurization are reported. Mandibulectomy was performed for mandibular malignancy in 3 cases. The resected bones were subsequently reimplanted after treatment with pasteurization in 3 cases to eradicate tumor cells involved in the resected bone. Although postoperative infection was observed in 2 of 3 cases, reimplantation of the resected mandibular bone treated by pasteurization was finally successful. Ten to 22 years of follow-up was carried out. Pasteurization was able to devitalize tumor cells involved in the resected bone and to preserve bone-inductive activity. Reimplantation of pasteurization could be a useful strategy for reconstruction of the mandible in patients with mandibular malignancy.

Sinus augmentation surgery after endoscopic sinus surgery for the treatment of chronic maxillary sinusitis: a case report.

Chronic sinusitis develops when the ostiomeatal complex becomes stenosed by the swelling of the sinus mucosa. Previously, the Caldwell-Luc method was performed for the treatment of chronic sinusitis. But postoperative complications, such as discomfort of the buccal skin and recurrence of sinusitis, frequently occurred after the operation. Today, endoscopic sinus surgery (ESS) has become widely used for the treatment of chronic sinusitis. The features of ESS allow for the restoration of the physical function of the sinus membrane and preservation of the physiological environment of the sinus. Therefore, sinus augmentation surgery can be safely performed at an insufficient alveolar bone height below the maxillary sinus when sinusitis is eliminated by the ESS. This article documents a patient history involving chronic sinusitis that was treated by the ESS therapy before sinus augmentation surgery as a pretreatment for insertion of dental implants.

Breakage and migration of a high-speed dental hand-piece bur during mandibular third molar extraction: Two case reports.

RATIONALE: Tooth extraction is a common dental surgical procedure. There is a possibility that various complications often occur during third molar tooth extractions. PATIENT CONCERNS: The authors report herein 2 cases of migration of a high-speed dental hand-piece bur during mandibular third molar extraction-one case with the iatrogenic foreign body migrating into the mandibular body and another case with the iatrogenic foreign body migrating into the floor of mouth are reported. DIAGNOSIS: The patient was diagnosed with the iatrogenic foreign body associated with mandibular third molar extraction by imaging examinations. INTERVENTIONS: The authors performed elective surgery to remove the foreign body under general anesthesia in Case 1, and performed emergency surgery to remove the foreign body under local anesthesia in Case 2. OUTCOMES: The foreign bodies were removed, and complete removal of the foreign bodies was confirmed by postoperative x-ray examination. The patients' postoperative courses were uneventful. LESSONS: The selection of adequate surgical procedures and instruments will prevent the occurrence of iatrogenic foreign bodies. If migration accidents occur, their positions should first be confirmed by imaging examinations. Dentists and/or oral surgeons should perform removal operations considering the degree of emergency based on the results of imaging examinations.

Oral liposarcoma in elderly: Case report and literature analysis.

RATIONALE: Oral liposarcoma is an extremely rare lesion that is often clinically misdiagnosed as a benign lesion because of its asymptomatic and indolent clinical course. we report a case of atypical lipomatous tumor/well-differentiated liposarcoma (ALT/WDL) of buccal mucosa, provisionally diagnosed as lipoma. PATIENT CONCERNS: A 97-year-old female was referred to dentistry and oral surgery department with an asymptomatic mass on the right buccal mucosa which had been present for an unknown period of time. DIAGNOSIS: Magnetic resonance imaging demonstrated a well-circumscribed lesion at the right buccal mucosa, and a lipoma was suspected. INTERVENTIONS: Surgical removal was performed, and a diagnosis of ALT/WDL was made. She and her family refused additional treatment due to her age. OUTCOMES: At the 10 months follow-up, the patient remained free of disease. LESSONS: The indolent clinical course and small size of oral liposarcoma can lead to provisional clinical diagnosis of benign lesion.

A floating inferior alveolar neurovascular bundle in a simple bone cyst: A case report.

Simple bone cysts (SBCs) are uncommon lesions that usually occur in the long bones of the skeleton and in the body of the mandible. Displacement of the mandibular canal due to cystic lesions have been reported previously. However, there have been no reports in which endoscopy has been utilized to observe an inferior alveolar neurovascular bundle in the lesion lumen. This current study presents a case of mandibular SBC accompanied by a floating inferior alveolar neurovascular bundle. A 13-year-old boy presented to the Department of Dentistry and Oral Surgery, University of Fukui in March 2017 with a painless swelling in the right buccal region. He was treated with fenestration surgery using the tooth extraction socket of the right mandibular third molar. An endoscopic view of the lesion lumen presented a surrounding cortical bone without an epithelial lining and the floating inferior alveolar neurovascular bundle that was consistent with the linear low signal area of the preoperative T2-weighted magnetic resonance imaging. SBC often develops in young people, and as such is minimal surgical invasion is preferable. The current case indicated that clinicians should consider the possibility of the floating inferior alveolar neurovascular bundle in the lesion and should not damage the neurovascular bundle in the narrow surgical field.

Prevalence of Tongue Cleaning Using a Toothbrush: A Questionnaire Survey in Fukui Prefecture, Japan.

OBJECTIVE: The aim of this study was to investigate the tongue cleaning habits using toothbrushes among outpatients of the University of Fukui Hospital and a private hospital in Fukui Prefecture. METHODS: We administered a questionnaire survey to volunteers detailing tongue cleaning habits using toothbrushes. The content of the questions in this survey were as follows: gender, age, frequency of tongue cleaning, portion of tongue cleaning, and purposes of tongue cleaning. RESULTS: We had 1,014 volunteers of various ages participating in this study. Regarding the frequency of tongue cleaning, 187 (18.4%) of all participants replied, "Every day", and 346 (34.1%) replied, "Sometimes". Regarding tongue cleaning of the 533 participants with active tongue cleaning habits, 242 (45.4%) participants replied, "The center of the dorsum of the tongue", and 274 (51.4%) replied, "The entire tongue". When analyzing the purpose of tongue cleaning, 346 (64.9%) participants replied, "To remove the tongue stain", 192 (36.0%) participants replied, "To remove the tongue coating", and 240 (45.0%) participants replied, "To manage halitosis". CONCLUSIONS: This study clarified that a wide range of age groups in the nonhospitalized general public practiced tongue cleaning habits using a toothbrush for various purposes.

Ossifying fibroma in the mandibular angle mimicking metastatic clear cell renal cell carcinoma: A case report.

RATIONALE: Ossifying fibroma is benign fibro-osseous neoplasm. The authors report a case of ossifying fibroma in the mandibular angle suspected as metastasis of clear cell renal cell carcinoma. PATIENT CONCERNS: A 74-year-old man presented to the primary hospital complaining of frequent urination. A tumor in the left kidney was detected via an abdominal computed tomography scan. The patient then visited the Department of Urology at our hospital. DIAGNOSES: According to whole-body imaging examinations, the patient was suspected of having renal cancer with mandibular metastasis. Also, a cystic lesion of the maxilla was revealed. INTERVENTIONS: Left nephrectomy was performed by urologists, and the patient was diagnosed with clear cell renal cell carcinoma of the left kidney. Approximately 1 month later, resection with a safety margin of the mandibular lesion and removal of the maxillary lesion were performed by oral and maxillofacial surgeons. OUTCOMES: The patient was diagnosed with ossifying fibroma of the mandible and an odontogenic keratocyst of the maxilla via a histopathological examination. Eighteen months have passed since the operation without clinical and imaging findings associated with recurrence. LESSONS: Ossifying fibroma in the mandibular angle of elderly patients is extremely rare. Surgeons should consider the possibility of metastasis when osteolytic lesions of the jaw are found in patients with cancer.