Prognostic value of a mandibular canal staging system for primary lesions in patients with lower gingival squamous cell carcinoma: a multicenter, retrospective study.

BACKGROUND: The Union for International Cancer Control and American Joint Committee on Cancer tumor staging system is used globally for treatment planning. As it may be insufficient for tumor staging of lower gingival carcinomas, we proposed the mandibular canal tumor staging system. In this study, we aimed to compare the two systems for such tumor staging and to identify prognostic markers. METHODS: This multicenter, retrospective study included patients with lower gingival squamous cell carcinoma who underwent radical surgery during 2001-2018. We compared survival rates (Kaplan-Meier estimator) and patient stratification according to the two systems. RESULTS: The proposed system yielded more balanced patient stratification than the existing system. Progression in the tumor grade according to the proposed system was associated with a poorer prognosis. The 5-year overall and disease-specific survival rates for the entire cohort were 74.9% and 81.8%, respectively. Independent factors affecting overall survival were tumor stage according to the proposed system, excision margins, and number of positive nodes, whereas those affecting disease-specific survival were excision margins and number of positive nodes. CONCLUSIONS: Subsite-specific tumor classification should be used for patients with oral cancer, and our results suggest that mandibular canal tumor classification may be effective for patients with lower gingival carcinoma.

Analysis of Oral and Gut Microbiome Composition and Its Impact in Patients with Oral Squamous Cell Carcinoma.

The impact of gut and oral microbiota on the clinical outcomes of patients with oral squamous cell carcinoma (OSCC) is unknown. We compared the bacterial composition of dental plaque and feces between patients with OSCC and healthy controls (HCs). Fecal and dental plaque samples were collected from 7 HCs and 18 patients with OSCC before treatment initiation. Terminal restriction fragment-length polymorphism analysis of 16S rRNA genes was performed. Differences in bacterial diversity between the HC and OSCC groups were examined. We compared the occupancy of each bacterial species in samples taken from patients with OSCC and HCs and analyzed the correlation between PD-L1 expression in the tumor specimens and the occupancy of each bacterial species. The gut and oral microbiota of patients with OSCC were more varied than those of HCs. Porphyromonas and Prevotella were significantly more abundant in patients with OSCC than in HCs. The abundance of Clostridium subcluster XIVa in the gut microbiota of the PD-L1-positive group was significantly greater than that in the PD-L1-negative group. The oral and gut microbiomes of patients with OSCC were in a state of dysbiosis. Our results suggest the possibility of new cancer therapies targeting these disease-specific microbiomes using probiotics and synbiotics.

Imaging findings and treatment outcomes of a rare subtype of medication-related osteonecrosis of the jaw.

INTRODUCTION: In our previous study, we found a rare type of medication-related osteonecrosis of the jaw (MRONJ), which shows periosteal reaction (PR) at a site distant from osteolytic lesions or the extraction site (periosteal reaction dominant type, PRd type), even though the osteolytic lesions in the bone marrow are localized. The causes and treatment of MRONJ remain unclear; hence, this study aimed to describe the imaging and clinical features of the PRd type. MATERIALS AND METHODS: MRONJ patients who visited Nagasaki University Hospital between 2009 and 2020 and received conservative therapy as initial treatment were included in this study. The PR site, imaging findings, initial symptoms, outcome, and time to progression were examined. RESULTS: Among 59 MRONJ patients treated with conservative therapy, 38 did not show PR (PR- type), 15 showed PR near the osteolytic region (PR + type), and 6 had the PRd type. All patients with the PRd type had submental abscesses, and computed tomography (CT) images demonstrated PR on the lingual side of the anterior mandible. Osteolytic lesions progressed in 6/6 PRd type (100%), 5/15 PR + type (33.3%), and 2/38 PR- type (5.3%) patients. Time to progression for the osteolytic region on CT was short for the PRd type, at 56-148 days (median 79 days). CONCLUSION: Among the MRONJ types, the PRd type has a poor prognosis. Therefore, accumulating and analyzing more PRd cases in the future is warranted. This is the first report to describe the presence of this specific subtype of MRONJ.

Effect of periosteal reaction in medication-related osteonecrosis of the jaw on treatment outcome after surgery.

INTRODUCTION: Surgical treatment in patients with medication-related osteonecrosis of the jaw (MRONJ) is superior to conservative treatment. However, treatment outcome in patients with periosteal reaction (PR) was significantly poorer than that of those without PR. The purpose of this retrospective study was to analyze the pathophysiology and clinical significance of PR in MRONJ. MATERIALS AND METHODS: Out of 181 patients with MRONJ undergoing surgery, 38 patients with PR were enrolled in the study. CT examinations, histological examinations, and bacteriological examinations using real-time polymerase chain reaction were performed, and the relationship among the opted surgical method, CT findings, and treatment outcome was investigated. RESULTS: The pattern of PR was classified into three types: type 1, new bone is formed parallel to the mandible, and no gap was evident between the mandible and new bone; type 2, new bone is formed parallel to the mandible, and a gap was evident between them; type 3, an irregular shape. Histological examinations revealed inflammatory tissue in the area visualized as a gap on CT. Bacteriological examination showed the presence of bacteria in the type 2 or type 3 PR. Complete cure was observed in 21 of 38 (55.3%) patients, which was lower than the cure rate of 73.4% in 143 patients without PR. The cure rate was significantly lower in cases with type 3 PR or with persistent osteolysis. CONCLUSIONS: It seems that complete resection of both osteolytic area and type 3 PR is necessary to obtain complete healing in patients undergoing marginal mandibulectomy.

Periosteal reaction of medication-related osteonecrosis of the jaw (MRONJ): clinical significance and changes during conservative therapy.

PURPOSE: We previously reported that the periosteal reaction (PR) in medication-related osteonecrosis of the jaw (MRONJ) is a poor prognostic factor in surgical cases, but it is not clear how PR changes during conservative therapy. The purpose of this retrospective study was to compare computed tomography (CT) findings at the first visit and during follow-up visits in MRONJ patients subjected to conservative therapy and to investigate factors associated with the exacerbation of PR during conservative therapy. METHODS: Sixteen patients with MRONJ of the lower jaw who underwent conservative therapy and experienced a PR on CT images at the first visit and underwent CT examination again after 6 months or more were enrolled in the study. Clinical features and CT findings (extent of osteolytic lesion, extent of PR, type of PR, and changes during conservative treatment) were investigated. RESULTS: On the second CT scan, the osteolytic lesion improved in 4 patients, had not changed in 5, and deteriorated in 7, whereas the PR improved in 5 patients, had not changed in 4, and deteriorated in 7 patients. PR was significantly deteriorated in patients who continued to receive antiresorptive agents during conservative treatment and in patients with deteriorated osteolytic lesions. CONCLUSION: PR in MRONJ often expands during conservative therapy and the PR type progresses from the attached type to the gap type, and the irregular type, but discontinuation of antiresorptive agent may improve PR as well as osteolytic lesions.

Awareness of Complications of Dental Treatment in Patients Treated with Drugs Affecting the Immune System : A Nationwide Questionnaire Survey of Dental Practitioners in Japan.

The aim of this study was to investigate the awareness and experience, among dental practitioners, of adverse events resulting from dental treatment of patients undergoing therapy with drugs that affect the immune system [angiogenesis inhibitors, biological agents, immunosuppressants, and disease-modifying anti-rheumatic drugs (DMARDs)]. For this purpose, a nationwide questionnaire survey was conducted. Questionnaires were sent to 2,050 dentists, of which 206 (10.1%) were completed and returned. The results showed that most dentists were aware of complications associated with dental treatment of patients treated with drugs that affect the immune system, and about half had actually experienced such complications. Delayed wound healing, osteonecrosis of the jaw (ONJ), and postoperative infections were reported. Whereas approximately 50% of dentists did not discontinue the drugs during dental treatment, about 18% did. During temporary drug discontinuation, some patients experienced aggravation of the primary disease, such as worsening of rheumatism, growth of tumors, and rejection reactions of transplanted organs. As for medical cooperation, only less than half of the dentists were asked for oral hygiene management by a physician prior to starting the drug treatment. Prospective studies are needed because evidence for dental treatments in patients treated with these drugs remains limited.

Drug holiday clinical relevance verification for antiresorptive agents in medication-related osteonecrosis cases of the jaw.

Treatment strategies of medication-related osteonecrosis of the jaw (MRONJ) are controversial. Recently, surgical treatment has been reported as superior to nonsurgical treatment, but the contribution discontinued antiresorptive agent use during MRONJ treatment remains unclear. This study aimed to evaluate the efficacy of drug holidays and treatment strategies in MRONJ cases. Four-hundred and twenty-seven patients with MRONJ treated at nine hospitals from 2009 to 2017 were included in this multicenter retrospective study. Multivariate Cox regression analysis showed that the primary disease (osteoporosis or malignant tumor), diabetes, serum albumin, and treatment method (surgical or nonsurgical) were significantly correlated with the cure rate. The cumulative 1-year cure rates in the surgical and nonsurgical treatment groups were 64.7% and 18.2%, respectively. However, discontinuing antiresorptive agents did not influence the treatment outcome in the cohort overall, or in 230 patients after performing propensity score matching among the discontinuation and continuation groups. When stratifying by treatment method, antiresorptive agent discontinuation significantly increased the cure rate in patients with osteoporosis who underwent nonsurgical treatment. In patients with malignant tumors undergoing nonsurgical therapy, discontinuing the antiresorptive agent was associated with a better treatment outcome, but not with statistical significance. In contrast, drug holidays showed no effect on improving outcomes in patients with both osteoporosis and malignant tumors who underwent surgical therapy. Thus, regardless of the primary disease, discontinuing antiresorptive agents during treatment for MRONJ may not be necessary and may be helpful in some cases. Future prospective trials should examine this question further.

Topical povidone iodine inhibits bacterial growth in the oral cavity of patients on mechanical ventilation: a randomized controlled study.

BACKGROUND: Topical 0.12% chlorhexidine has been used widely to prevent ventilator-associated pneumonia in patients undergoing mechanical ventilation. However, it is not approved for mucosal application in Japan. The aims of this study were to investigate if topical povidone iodine (i) inhibits bacterial growth and (ii) disrupts the balance of the oral microbiota. METHODS: This randomized controlled clinical trial included 23 patients who underwent mechanical ventilation in the intensive care unit. The patients were divided randomly into two groups: the intervention group (n = 16) and the control group (n = 7). All patients received oral cleaning with 3% hydrogen peroxide, followed by irrigation with tap water. The patients in the intervention group received 10% povidone iodine applied topically to the oral cavity. The concentration of total bacteria in the oropharyngeal fluid were determined before, immediately after, 1 h, 2 h, and 3 h after oral care using the Rapid Oral Bacteria Quantification System, which is based on dielectrophoresis and impedance measurements. The number of streptococci, methicillin-resistant Staphylococcus aureus, Streptococcus pneumoniae, Pseudomonas aeruginosa, Porphyromonas gingivalis, and Candida albicans before, immediately after, 1 h, and 3 h after oral care were estimated based on real-time polymerase chain reaction data. RESULTS: After irrigation of the oral cavity, the number of bacteria decreased, but increased again at 1 h after oral care in the control group; however, in the intervention group, the concentration of bacteria was significantly lower than that in the control group at 1 hour (p = 0.009), 2 h (p = 0.001), and 3 h (p = 0.001) after oral care. The growth of all bacterial species tested was inhibited in the intervention group at 3 h after oral care, suggesting that povidone iodine did not disturb the balance of the oral microbiota. CONCLUSIONS: Topical application of povidone iodine after cleaning and irrigation of the oral cavity inhibited bacterial growth in the oropharyngeal fluid of patients on mechanical ventilation while not disrupting the balance of the oral microbiota. TRIAL REGISTRATION: University Hospitals Medical Information Network Clinical Trials Registry (UMIN-CTR), UMIN000028307. Registered 1 September 2017.

Clinical significance of periosteal reaction as a predictive factor for treatment outcome of medication-related osteonecrosis of the jaw.

Regarding treatment strategies for medication-related osteonecrosis of the jaw (MRONJ), surgical therapy has recently been reported to be more effective than conservative therapy. However, some patients did not achieve complete healing, even when extensive surgery was performed. Periosteal reaction in MRONJ patients is often observed by the CT examination. Tssshe purpose of this study was to investigate the relationship between periosteal reaction and treatment outcome of MRONJ. A total of 164 surgeries in 136 patients with MRONJ at two hospitals were included in the study. Correlations between various clinical and radiographic factors and treatment outcome were examined with Cox regression analysis. The results showed that the presence of periosteal reaction, as well as primary disease involving malignant tumor, were independent risk factors related to poor outcome. Furthermore, we examined factors related to the occurrence of the periosteal reaction and found that 4 variables were significantly correlated with periosteal reaction by multivariate analysis: gender (female), site (lower jaw), primary disease (malignant tumor), and osteosclerosis (severe). The present study clarified that the cure rate after surgical treatment decreased in cases with periosteal reaction, suggesting that it is necessary to review the treatment method.

Clinical observation of tongue coating of perioperative patients: factors related to the number of bacteria on the tongue before and after surgery.

BACKGROUND: Increased amount of tongue coating has been reported to be associated with increased bacteria count in the saliva and aspiration pneumonia in elderly people. However, the implications of tongue coating for prevention of postoperative complications in patients undergoing major oncologic or cardiac surgery has not been well documented. The purpose of this study is to investigate the number of bacteria on the tongue before and after surgery and factors affecting it. METHODS: Fifty-four patients who underwent oncologic or cardiac surgery under general anesthesia at Nagasaki University Hospital were enrolled in the study. Various demographic, tumor-related, treatment-related factors, and the number of bacteria on the tongue and in the saliva were examined, and the relationship among them was analyzed by Mann-Whitney U test, Spearman rank correlation coefficient, or multiple regression. RESULTS: Before surgery, no significant factors were correlated with the number of bacteria on the tongue, and there were no relationship between bacteria count on the tongue and that in the saliva. On the next day after surgery, bacteria on the tongue increased, and sex, periodontal pocket depth, feeding condition, dental plaque, blood loss, and bacteria in the saliva were correlated with bacteria on the tongue by a univariate analysis. A multivariate analysis showed that feeding condition, and amount of dental plaque were correlated with the number of bacteria. CONCLUSIONS: Increased number of bacteria on the tongue was associated with feeding condition and amount of dental plaque. Further studies are necessary to clarify the clinical significance of dental coating in perioperative oral management of patients undergoing oncologic or cardiac surgery.

Multicenter Retrospective Study of the Risk Factors of Hemorrhage After Tooth Extraction in Patients Receiving Antiplatelet Therapy.

PURPOSE: To identify the risk factors affecting hemorrhage after tooth extraction in patients receiving antiplatelet therapy, this study investigated the relation between various factors and hemorrhage events after tooth extraction. PATIENTS AND METHODS: The records of 264 patients receiving antiplatelet therapy who underwent tooth extraction were retrospectively reviewed from 6 institutions belonging to the Japanese Study Group of Cooperative Dentistry with Medicine. Demographic information, hemorrhage events after tooth extraction, the presence or absence of comorbidities, antiplatelet agent, the use of preoperative antibiotics or nonsteroidal anti-inflammatory drugs, number of teeth extracted, serum creatinine level, estimated glomerular filtration rate, and alanine transaminase level were assessed. Risk factors for hemorrhage after tooth extraction were evaluated by univariate and multivariate analyses. RESULTS: The study population of 264 patients consisted of 153 men and 111 women with a mean age of 73.6 years (range, 24 to 96 yr). Six hundred ninety-four teeth were extracted (mean, 2.6 ± 2.3 teeth per patient). In patients receiving antiplatelet therapy, the frequency of hemorrhage after tooth extraction, including mild and self-controlled hemorrhages, was 17.4%. Univariate analysis showed that serum creatinine level and dual antiplatelet therapy were correlated with hemorrhage after tooth extraction (P = .001 and P = .049, respectively). Only serum creatinine was identified as an independent risk factor for hemorrhage after tooth extraction in patients receiving antiplatelet therapy (P = .037). CONCLUSIONS: The risk of hemorrhage after tooth extraction is increased in patients receiving dual antiplatelet therapy with or without chronic kidney disease. Local hemostatic treatments, such as at least suturing, are recommended.

Carcinoma Ex Pleomorphic Adenoma of the Tongue: Difficulty in Diagnosis Between Metastasis of Breast Cancer and Salivary Tumor.

Carcinoma ex pleomorphic adenoma (CEPA) is a carcinoma that shows histologic evidence of arising in or from a benign pleomorphic adenoma. Carcinoma ex pleomorphic adenoma often occurs in parotid glands, but is extremely rarely in the tongue. A 53-year-old Japanese woman was referred to the Department of Oral and Maxillofacial Surgery, Nagasaki University Hospital, because of tumor of the right dorsum tongue. She had a history of surgery of breast cancer (invasive ductal carcinoma) and it was disseminated to the lung and bone. Macroscopic examination revealed an oval tumor with a smooth mucosal surface of 10 mm in diameter in the right dorsum tongue. A clinical diagnosis was metastasis from breast cancer or primary salivary gland tumor. Histologic diagnosis of the biopsy specimen was CEPA. She underwent partial glossectomy under general anesthesia. The final diagnosis of surgical materials was CEPA based on the differential diagnosis from breast carcinoma. She is alive bearing disseminated breast carcinoma without recurrence of CEPA at 6 months after glossectomy.

Clinicopathological Study of Primary Intraosseous Squamous Cell Carcinoma of the Jaw and a Review of the Literature.

PURPOSE: Primary intraosseous squamous cell carcinoma (PIOSCC) is a rare malignant odontogenic tumor that originates from odontogenic epithelial remnants. It is often difficult to diagnose PIOSCC definitively; hence, extraction or surgical treatment is performed before the initial diagnosis in most cases. The present study examined new insights into and prognostic factors of patients with PIOSCC admitted to the authors' department. MATERIALS AND METHODS: An extensive record review was conducted of patients who underwent radical surgery for PIOSCC from January 2001 through December 2014. RESULTS: Of all cases of OSCC, the frequency of PIOSCC was 1.45%. The 2-year relapse-free survival (RFS) and overall survival (OS) rates were 50.0 and 41.6% in all cases, respectively. Three patients underwent surgery or tooth extraction before the initial diagnosis; in fact, intervention before initial diagnosis was found to be an important poor prognostic factor for RFS and OS. In contrast, patients who were not treated before the initial diagnosis was made did not exhibit any locoregional recurrence. CONCLUSIONS: The treatment of PIOSCC should be similar to that for oral cancer with at least clinical stage T3N0 in the National Comprehensive Cancer Network clinical practice guidelines. In addition, cases of PIOSCC that are not treated before the initial diagnosis are more likely to obtain a good prognosis.

The effect of tooth brushing, irrigation, and topical tetracycline administration on the reduction of oral bacteria in mechanically ventilated patients: a preliminary study.

BACKGROUND: One of the main causes of ventilator-associated pneumonia (VAP) is thought to be aspiration of oropharyngeal fluid containing pathogenic microorganisms. The aim of this study was to examine the effects of various oral care methods on the reduction of oral bacteria during intubation. METHODS: First, the effect of mechanical oral cleaning was investigated. The bacterial count on the tongue and in the oropharyngeal fluid was measured after tooth brushing, irrigation, and three hours after irrigation in mechanically ventilated patients at the intensive care unit (ICU). Next, the efficacy of topical administration of tetracycline and povidone iodine on the inhibition of bacterial growth on the tongue and in the oropharyngeal fluid was examined in oral cancer patients during neck dissection. RESULTS: The number of bacteria in the oropharyngeal fluid was approximately 10(5)-10(6) cfu/mL before surgery, but increased to 10(8) cfu/mL after intubation. Oral care with tooth brushing and mucosal cleaning did not reduce oral bacteria, while irrigation of the oral cavity and oropharynx significantly decreased it to a level of 10(5) cfu/mL (p < 0.001). However, oral bacteria increased again to almost 10(8) cfu/mL within three hours of irrigation. Oral bacteria did not decrease by topical povidone iodine application. In contrast, 30 min after topical administration of tetracycline, the number of oral bacteria decreased to 10(5) cfu/mL, and remained under 10(6) cfu/mL throughout the entire experimental period of 150 min. CONCLUSIONS: While the present studies are only preliminary, these results indicate that irrigation of the oral cavity and oropharynx followed by topical antibiotic administration may reduce oral bacteria in mechanically ventilated patients. TRIAL REGISTRATION: UMIN000018318 , 1 August 2015.

Granular cell ameloblastoma: case report of a particular ameloblastoma histologically resembling oncocytoma.

Granular cell ameloblastoma is classified as a histological subtype of solid/multicystic ameloblastoma. Usual granular cell ameloblastoma is histologically characterized by granular changes of stellate-like cells located in the inner portion of the epithelial follicles. Here we report a case of another type of granular cell ameloblastoma, showing predominant anastomosing double-stranded trabeculae of granular cells. This type of granular cell ameloblastoma is extremely rare, and the World Health Organization classification does not contain the entity. We tentatively termed it 'anastomosing granular cell ameloblastoma' in this report. The present case suggests the importance of differential diagnosis because the histology of 'anastomosing granular cell ameloblastoma' resembles that of salivary gland oncocytoma rather than that of usual granular cell ameloblastoma. The trabeculae observed in our case continued to the peripheral cells of a small amount of epithelial sheets of plexiform ameloblastoma, and the tumor cells were positive for CK19, which is regarded as an immunohistochemical marker of odontogenic epithelium. Similar to usual granular cell ameloblastoma, the tumor cells had CD68-positive granules. For precise diagnosis of this condition, immunohistochemistry using CK19 and CD68, as well as detailed histological observation, are recommended.

Application of polyglycolic acid sheets and fibrin glue spray to bone surfaces during oral surgery: a case series.

PURPOSE: Previous studies have described the use of a combination of polyglycolic acid (PGA) sheets (a resorbable biomaterial) and fibrin glue spray to treat open soft tissue wounds during oral surgery, which have produced good results. However, there have not been any detailed investigations of the use of these materials to treat exposed hard tissue wounds. This study investigated the combination of PGA sheets and fibrin glue spray to treat exposed bone surfaces during oral surgery. MATERIALS AND METHODS: PGA sheets and fibrin glue spray were applied to exposed bone surfaces after lesion resection in 8 patients (10 sites) who had been diagnosed with malignant tumors. The sheets were cut into pieces (width, 5 to 10 mm) and applied to the exposed bone surface. RESULTS: PGA adhesion was confirmed for the final time on postoperative days 28 to 56 (mean, 35.8 days), and there were no cases in which the PGA sheets fell off the wound prematurely. Epithelialization of the wound surface occurred gradually and was complete by postoperative weeks 4 to 5, regardless of the size of the wound. CONCLUSION: This method was considered very effective at preventing postoperative bleeding, alleviating postoperative pain, and promoting epithelialization during the reconstruction of bone surfaces after tumor resection in the oral cavity.

Transformation of an odontogenic keratocyst into a solid variant of odontogenic keratocyst/keratoameloblastoma during long­term follow­up: A case report.

Keratoameloblastoma (KA) and solid variant of odontogenic keratocyst (SOKC) are rare odontogenic lesions, and their relationship and differences are unclear. The present study described a case that started as an odontogenic keratocyst (OKC) and transformed to SOKC/KA upon recurrence. Briefly, a 26­year­old man presented with swelling in the right cheek and was referred to the Department of Oral and Maxillofacial surgery, Hiroshima University Hospital (Hiroshima, Japan). At the initial visit, unicystic bone permeation was observed extending from the right canine to the molar, maxillary sinus and nasal cavity. After the biopsy, the patient underwent excisional surgery and was diagnosed with OKC. Thereafter, the lesion recurred six times over a period of 13 years and showed different histopathological features from those of the primary lesion, all consisting of numerous cysts with keratinization, which were diagnosed as SOKC/KA. The Ki­67 positivity rate was ~10%, which was higher than that of the primary lesion, but there was no atypia. Genetic analysis of the recurrent lesion revealed mutations in adenomatous polyposis coli and Kirsten rat sarcoma viral oncogene homolog. This case originated from OKC, and the morphological features of OKC and KA were mixed upon recurrence, supporting the commonality and association between the two. However, multiple mutations different from those of OKC and ameloblastoma were detected, suggesting an association of SOKC/KA with increased proliferative activity and a high recurrence rate.

Shotgun metagenomic analysis of saliva microbiome suggests Mogibacterium as a factor associated with chronic bacterial osteomyelitis.

Osteomyelitis of the jaw is a severe inflammatory disorder that affects bones, and it is categorized into two main types: chronic bacterial and nonbacterial osteomyelitis. Although previous studies have investigated the association between these diseases and the oral microbiome, the specific taxa associated with each disease remain unknown. In this study, we conducted shotgun metagenome sequencing (≥10 Gb from ≥66,395,670 reads per sample) of bulk DNA extracted from saliva obtained from patients with chronic bacterial osteomyelitis (N = 5) and chronic nonbacterial osteomyelitis (N = 10). We then compared the taxonomic composition of the metagenome in terms of both taxonomic and sequence abundances with that of healthy controls (N = 5). Taxonomic profiling revealed a statistically significant increase in both the taxonomic and sequence abundance of Mogibacterium in cases of chronic bacterial osteomyelitis; however, such enrichment was not observed in chronic nonbacterial osteomyelitis. We also compared a previously reported core saliva microbiome (59 genera) with our data and found that out of the 74 genera detected in this study, 47 (including Mogibacterium) were not included in the previous meta-analysis. Additionally, we analyzed a core-genome tree of Mogibacterium from chronic bacterial osteomyelitis and healthy control samples along with a reference complete genome and found that Mogibacterium from both groups was indistinguishable at the core-genome and pan-genome levels. Although limited by the small sample size, our study provides novel evidence of a significant increase in Mogibacterium abundance in the chronic bacterial osteomyelitis group. Moreover, our study presents a comparative analysis of the taxonomic and sequence abundances of all genera detected using deep salivary shotgun metagenome data. The distinct enrichment of Mogibacterium suggests its potential as a marker to distinguish between patients with chronic nonbacterial osteomyelitis and chronic bacterial osteomyelitis, particularly at the early stages when differences are unclear.

Management of maxillary alveolar bone fracture and severely intruded maxillary central incisor: report of a case.

An 11-year-old male who injured his maxilla and right maxillary central incisor and lip during a fall was presented to our hospital. His lower lip and upper gingiva were lacerated with swelling and epistaxis, and he had a maxillary alveolar bone fracture and severe intrusion of the right maxillary central incisor, which had penetrated the floor of the nasal cavity with avulsion. Under local anesthesia, we repositioned the incisor and bone segment and fixed them with a titanium micromesh plate and self-tapping screws and splints. The incisor was also treated by root canal 3 days after the operation and was restored with a crown. We performed root canal filling 1 month later. Five months later, the plate and screws were removed. In prognosis of our case, no symptoms of inflammatory root resorption or ankylosis have observed for more than 1 year and 6 months of follow up based on both clinical and radiographic findings.

Oral Bacterial Contributions to Gingival Carcinogenesis and Progression.

Several periodontitis-associated species induce genes related to cell proliferation, cell-cycle progression, apoptosis, intracellular transport, immune and inflammatory responses, carcinogenesis, and cancer progression. Here, we reviewed studies showing strong associations between gingival squamous cell carcinoma (GSCC) and three periodontitis-related oral bacteria (Porphyromonas gingivalis, Fusobacterium nucleatum, and Prevotella intermedia) in the microenvironment. These bacteria produce cytoplasmic lipopolysaccharide (LPS) and secrete cytokines and molecules related to carcinogenesis, tumor progression, and metastasis and metastasis. In GSCC, LPS levels are substantially elevated and assessable by functional analysis. Polymicrobial infections can synergistically induce inflammation and significantly upregulate proinflammatory molecules (e.g., IL1ß, IL8, and TNFα) that promote carcinogenesis. This review can facilitate the identification of novel targets for treating and preventing GSCC, which is potentially associated with periodontal pathogen.