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.

Is withdrawal of antiresorptive agents necessary before and after tooth extraction? A systematic review.

OBJECTIVES: The need for prevention and management of medication-related osteonecrosis of the jaw (MRONJ) has increased with the growing number of patients using antiresorptive agents. The scope of this systematic review (SR) was to determine whether the withdrawal of antiresorptive agents is necessary for tooth extractions in patients receiving each of the antiresorptive medications. MATERIALS AND METHODS: The searches were performed using the MEDLINE databases. We selected SRs, randomized controlled trials (RCTs), prospective and retrospective non-randomized clinical (observational) studies, and case reports/case series in this order of preference. RESULTS: We included one SR, one RCT, five observational studies, and three case reports. Meta-analyses were not conducted because the RCT had an extremely small sample size and the observational studies had different definitions of intervention and comparison that could not be integrated across studies. In this SR, no studies showed a benefit (i.e., a reduction in the incidence of osteonecrosis of the jaw) of short-term withdrawal of antiresorptive agents for tooth extraction. Additionally, no studies examined the harm (i.e., an increase in femoral and vertebral fractures and skeletal-related events during bone metastasis) of withdrawal for tooth extraction. CONCLUSIONS: We were unable to determine whether withdrawal before and after tooth extraction is necessary with a high certainty of evidence. Future systematic reviews including RCTs with larger samples are expected to provide such evidence. CLINICAL RELEVANCE: This systematic review provides evidence-based information for multidisciplinary collaborations related to patients receiving antiresorptive agents.

Association between dental extraction after radiotherapy and osteoradionecrosis: A multi-centre retrospective study.

OBJECTIVE: Radiotherapy (RT) carries a substantial risk for the development of osteoradionecrosis (ORN) of the jaw. This study was performed to investigate the relationship between dental extractions after RT and the development of ORN. MATERIAL AND METHODS: Thirty-two patients with head and neck cancer who underwent tooth extraction after RT were investigated for correlations between the development of ORN and various factors. RESULTS: Postextraction ORN was diagnosed in 12 (12.1%) teeth of 9 patients. The RT dose against the site of tooth extraction was 62.0 and 37.4 Gy in the ORN and Non-ORN groups, respectively (p < .001). The duration from RT to tooth extraction was 41.2 and 28.2 months in the ORN and Non-ORN groups, respectively (p = .025). Tooth extraction was significantly associated with ORN in patients with a high RT dose against the site (odds ratio = 1.231) and a longer duration of time from RT (odds ratio = 1.084). CONCLUSIONS: Extraction of non-restorable teeth and those with a poor prognosis should not necessarily be postponed even when patients are undergoing RT. However, clinicians should pay special attention to postoperative management after tooth extraction in patients with a high RT dose and longer time from RT.

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.

Relationship between dry mouth and hypertension.

OBJECTIVES: Salivary dysfunction, such as reduced salivary flow and an altered salivary composition, is caused by several diseases, medical conditions, and medications. The purpose of the present study was to clarify the relationship between hypertension and morphological changes in the submandibular glands. MATERIALS AND METHODS: An epidemiological study was conducted to elucidate the relationship between hypertension and dry mouth. The effects of hypertension on morphological changes and the intima thickness of arteries in the submandibular glands were histopathologically investigated. RESULTS: Among 1933 subjects in the epidemiological study, 155 (8.0%) had dry mouth. A multivariate analysis revealed that dry mouth correlated with age (p < 0.001), sex (p < 0.001), and hypertension (p < 0.05). No significant differences were observed in the size of the submandibular glands between patients with or without hypertension. The average area of acinar cells was smaller in patients with than in those without hypertension (0.366 ± 0.153 vs. 0.465 ± 0.178, p < 0.05). The arteriosclerotic index was significantly higher in patients with than in those without hypertension (0.304 ± 0.034 vs 0.475 ± 0.053, p < 0.05). CONCLUSIONS: Hypertension may contribute to the degeneration of the submandibular glands by decreasing the number of acinar cells and promoting fatty infiltration and stenosis of the arteries. CLINICAL RELEVANCE: There may be a correlation between hypertension and the degeneration of the submandibular glands by decreasing the number of acinar cells and promoting fatty infiltration and stenosis of the arteries.

Oral Candida Mannan Concentrations Correlate with Symptoms/Signs of Ill Health and the Immune Status.

BACKGROUND: A relationship has been proposed between increases in oral Candida concentrations and host immunity. Therefore, the present study was conducted to investigate the relationship between oral Candida mannan concentrations and symptoms/signs of ill health and the immune status and also to examine whether health/the immune status may be evaluated based on oral Candida mannan concentrations. PATIENTS AND METHODS: The health conditions of 25 healthy individuals and 10 cancer patients receiving cytotoxic chemotherapy were assessed using a questionnaire and oral rinse solutions collected on consecutive days. Candida mannan concentrations in oral rinse solutions were measured using a commercial sandwich ELISA kit. RESULTS: The use of dentures was identified as a significant independent factor increasing Candida mannan concentrations. In a stratified analysis based on the use of dentures, significantly increased Candida mannan concentrations were detected in healthy volunteers with chills and in cancer patients with slight/moderate fever (37.5-38.4 °C) (multivariate analysis, p < 0.01) who were non-denture users. These symptoms/signs may be associated with (pre-)infection, during which the immune system is activated and needs to function well. CONCLUSIONS: The present results suggest that oral Candida mannan concentrations are a predictive marker for health/the immune status.

On-lay grafting of a calcium hydroxyapatite bone substitute: A preliminary animal experimental study.

BACKGROUND: Bone substitutes are widely accepted for various clinical applications. However, the usage is predominantly intraosseous implantation, whereas extraosseous on-lay grafting is rare and lacks scientific evidence. The purpose of this study is to elucidate whether osteoconduction occurs in on-lay grafted bone substitute. METHODS: Custom-made interconnected porous calcium hydroxyapatite ceramic (IPCHA) was on-lay grafted with screw or anchor fixation (S- and A-groups, respectively) at the anterior aspect of the femur of skeletally mature Japanese white rabbits. At 3, 6 and 12 weeks postoperatively, 4 samples for each time point and each group were evaluated by microfocus computed tomography (micro-CT) and histology. RESULTS: Volume-rendered three-dimensional micro-CT images showed a high-density calcified area infiltrating IPCHA from the femoral cortex as of 6 weeks. When quantified, the calcified volume per unit volume first showed no difference between the two groups at 3 weeks but increased over time, and became significantly greater in the S-group than in the A-group (p = 0.012 and 0.004 at 6 and 12 weeks, respectively). Histologically, IPCHA pores were first occupied by fibrous tissue at 3 weeks; then, the pores adjacent to the femoral cortex were gradually replaced by bony tissue as of 6 weeks for both fixations. CONCLUSIONS: IPCHA allowed new bone formation inside the material even though it was implanted in an on-lay fashion on the cortical bone. Our results suggested that on-lay grafted IPCHA exerted its osteoconductivity well, with more new bone forming in screw-fixated samples than in anchor-fixated samples.

Treatment outcomes of adjunctive teriparatide therapy for medication-related osteonecrosis of the jaw (MRONJ): A multicenter retrospective analysis in Japan.

BACKGROUND: Therapeutic strategies for patients with medication-related osteonecrosis of the jaw (MRONJ) remain controversial. The aim of the present study was to clarify the effectiveness and safety of teriparatide therapy in Japanese MRONJ patients based on a large number of case series with a multicenter retrospective analysis. PATIENTS AND METHODS: Between January 2012 and December 2016, 29 patients who were diagnosed with MRONJ at 10 hospitals were treated with teriparatide. The medical records of these patients were retrospectively reviewed to assess the efficacy and safety of teriparatide therapy for MRONJ patients. RESULTS: Adverse events occurred in 17.2% of patients (5/29). One patient developed severe arthralgia and discontinued teriparatide therapy after 12 days, while others continued the treatment. Among 29 patients, the median period of administration of teriparatide was 14.0 months (range, 0.3-26 months), and treatment outcomes were evaluated as effective in 75.9% of patients with complete resolution in 65.5%. Among patients treated with oral bisphosphonates (BPs), 83.3% were effectively treated with teriparatide and 40% with intravenous BPs. The oral administration of BPs was associated with successful treatment outcomes with teriparatide (p = 0.062). CONCLUSIONS: Teriparatide therapy has potential as an effective treatment option for MRONJ.

Prevalence of and risk factors for postoperative hemorrhage after lower third molar extraction on warfarin therapy: a multicenter retrospective study in Japan.

Postoperative hemorrhage after tooth extraction is a critical and clinically important issue for clinicians and patients receiving anticoagulants. The purpose of the present study was to investigate the prevalence of and risk factors for postoperative hemorrhage after lower third molar extraction in Japanese patients receiving warfarin therapy. A total of 142 patients who underwent lower third molar extraction between January 2010 and December 2016 were included, and their medical records were retrospectively reviewed. The prevalence of and risk factors for postoperative hemorrhage were investigated. The prevalence of postoperative hemorrhage after lower third molar extraction was significantly higher in patients receiving warfarin than in healthy subjects (21.8% vs 0.7%, P < 0.001). The cutoff value for PT-INR was 2.11 based on a receiver-operating characteristic analysis. A multivariate analysis indicated that an elevated PT-INR value [hazard ratio (HR) 3.798, 95% confidence interval (CI) 1.400-10.467, P < 0.01], preoperative antibiotic administration (HR 4.434, 95% CI 1.591-14.775, P < 0.01), difficulties with intraoperative hemostasis (HR 16.298, 95% CI 2.986-110.677, P < 0.01), and higher serum creatinine levels (HR 7.465, 95% CI 1.616-39.576, P < 0.05) are significant predictors of postoperative hemorrhage after lower third molar extraction. Multivariate correlations were observed between risk factors including an elevated PT-INR value, preoperative antibiotic administration, and higher serum creatinine levels, and postoperative hemorrhage after lower third molar extraction in patients receiving warfarin therapy. Clinicians need to consider these risk factors for postoperative hemorrhage after the lower third molar extraction and monitor PT-INR in patients receiving warfarin therapy.

Treatment outcomes and prognostic factors of medication-related osteonecrosis of the jaw: a case- and literature-based review.

OBJECTIVES: The purpose of this study was to investigate the treatment outcomes and prognostic factors of medication-related osteonecrosis of the jaw (MRONJ) in Japanese patients. PATIENTS AND METHODS: Among 409 cases, treatment outcomes and prognostic factors were investigated in 275 patients. In statistical analyses, the 1-year cumulative curative rate was calculated with the Kaplan-Meier method, and significance was examined with the Wilcoxon test. Cox's proportional hazards regression analysis was used for the multivariate analysis. RESULTS: Resolution of the disease was achieved in 137 out of 275 MRONJ patients (49.8%). One-year cumulative curative rates were 39.8% in stage 1 patients, 26.3% in stage 2, and 19.0% in stage 3. The 1-year cumulative curative rates of treatment interventions were 17.2% for conservative treatment, 34.5% for sequestrectomy, and 40.7% for extended surgery including bone resection and segmental resection. As the prognostic factors of treatment outcomes, the type of medication, stage of MRONJ, and type of surgical intervention were identified as independent factors in a multivariate analysis. CONCLUSION: These results suggest that surgical interventions may lead to a good prognosis in MRONJ patients. CLINICAL RELEVANCE: This study indicated that surgical intervention for MRONJ might lead to improvement of prognosis and quality of life in MRONJ patients.

Relationship Between the Quantity of Oral Candida and Systemic Condition/Diseases of the Host: Oral Candida Increases with Advancing Age and Anemia.

BACKGROUND: The impact of host systemic conditions/diseases on the prosperity of oral Candida colonies remains unclear. The aim of the present study was to investigate whether a relationship exists between the quantity of oral Candida and the systemic condition/diseases of the host. PATIENTS AND METHODS: The cross-sectional relationship between Candida mannan concentrations and health check-up results was analyzed in consideration of local conditions that influence the prevalence of oral Candida. RESULTS: Candida mannan concentrations correlated with age, the number of untreated decayed teeth, number of prosthetic teeth, salivary pH, HbA1c, and the red blood cell count in a univariate analysis. In a multivariate analysis, Candida mannan concentrations correlated with age, the number of untreated decayed teeth, number of prosthetic teeth, salivary pH, and the red blood cell count. Candida mannan concentrations were higher in subjects older than 80 years, with a higher number of either untreated or prosthetic teeth, with a lower salivary pH, and with a decreased red blood cell count. Mannan concentrations were slightly higher in subjects with elevated HbA1c. CONCLUSIONS: The present results suggest a close relationship between the quantity of oral Candida and the systemic condition/diseases of the host. Oral Candida may increase in immunocompromised hosts.

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.

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.

Dental and oral management in the perioperative period of surgery: A scoping review.

Dental and oral management (DOM) is a long-established treatment modality. This scoping review aimed to narratively review previous studies, examine the effects of perioperative DOM, and identify the available evidence. A literature search was conducted using the PubMed electronic database for studies published between January 1, 2000, and March 8, 2022. The search yielded 43 studies, most of which were published in the last 10 years. The results of this study confirmed that improved perioperative oral hygiene is effective in preventing postoperative pneumonia. Our results also suggested that preoperative DOM is effective in preventing postoperative surgical site infections. Perioperative DOM is effective in reducing the incidence of postoperative pneumonia, SSI, and postsurgical complications. Further studies are needed to elucidate the various mechanism of DOM and to examine efficient intervention methods and timing.

Efficacy of perioperative oral care management in the prevention of surgical complications in 503 patients after pancreaticoduodenectomy for resectable malignant tumor: A multicenter retrospective analysis using propensity score matching.

BACKGROUND: Pancreaticoduodenectomy has been associated with a high mortality rate and significant postoperative morbidity. Recently, perioperative oral care management has been reported to be effective in preventing postoperative pneumonia and surgical site infection. In this study, we examined the effect of perioperative oral care management in reducing complications after pancreaticoduodenectomy, including surgical site infection. METHODS: This retrospective multicenter study included 503 patients who underwent pancreaticoduodenectomy at 8 facilities between January 2014 and December 2016. Among these, 144 received perioperative oral management by dentists and dental hygienists (oral management group), whereas the remaining 359 did not (control group). The oral care management program included oral health instructions, removal of dental calculus, professional mechanical tooth cleaning, removal of tongue coating, denture cleaning, instructions for gargling, and tooth extraction. The participants were matched using propensity scores to reduce background bias. Various factors were examined for correlation with the development of complications. RESULTS: The incidence of organ/space surgical site infection was significantly lower in the oral management group than in the control group (8.0% vs 19.6%, P = .005). Multivariable logistic regression analysis revealed that hypertension and lack of perioperative oral management were independent risk factors for organ/space surgical site infection. Lack of perioperative oral management had an odds ratio of 2.847 (95% confidence interval 1.335-6.071, P = .007). CONCLUSION: Perioperative oral care management reduces the occurrence of surgical site infections after pancreaticoduodenectomy and should be recommended as a strategy to prevent infections in addition to antibiotic use.

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.

Presence of periodontitis may synergistically contribute to cancer progression via Treg and IL-6.

A close causal relationship has been suggested to exist between cancer and periodontitis. We hypothesized that the immune surveillance system is impaired in patients with periodontitis, which contributes to cancer development and growth. Therefore, the present study investigated the relationship between immune surveillance mechanisms and periodontitis in cancer patients. The presence or absence of periodontitis was assessed and the peripheral blood (PB) concentrations of IL-6, immunosuppressive cytokines (VEGF, TGF-ß1, and CCL22) and proportion of T regulatory cells (Treg, CD3 + CD4 + CD25 + Foxp3 +) were measured. Subjects were classified into the following four groups: non-cancer patients without periodontitis (C - P -), non-cancer patients with periodontitis (C - P +), cancer patients without periodontitis (C + P -), and cancer patients with periodontitis (C + P +). The results of a multivariate analysis showed that the PB concentration of IL-6 was significantly higher in C + than in C- and higher in C + P + than in C + P -. The PB proportion of Treg was significantly higher in C + P + than in C + P -, C - P + , and C - P -. The results of this study suggested that the presence of periodontitis and cancer synergistically increased Treg in PB, which may be one of the underlying causes of immunosuppression and immune evasion in cancer. It was also suggested that the presence of periodontal disease and/or cancer also increases IL-6 in PB, which would be associated with cancer progression. These results suggest the possibility that the presence of periodontitis might synergistically contribute to cancer progression.

Risk factors for osteoradionecrosis of the jaw in patients with oral or oropharyngeal cancer: Verification of the effect of tooth extraction before radiotherapy using propensity score matching analysis.

Background/purpose: Osteoradionecrosis of the jaw (ORN) often occurs in patients with head and neck cancer undergoing radiotherapy (RT). It has been recommended to extract the tooth before RT that may become source of infection, but in recent years, some investigators have reported that tooth extraction before RT increase the risk of developing ORN and therefore should be avoided. The purpose of the study is to evaluate the risk factors for ORN including tooth extraction before RT. Materials and methods: This was a retrospective study of 366 patients with oral or oropharyngeal cancer who underwent RT of 50 Gy or more at six university hospitals, with follow-up of at least six months post-RT. The relationship between each factor and ORN incidence was analyzed using the Cox proportional hazard model. Results: Periapical lesions, more than 50% loss of alveolar bone, and tooth extraction after RT significantly correlated with ORN. Intensity-modulated RT showed a lower incidence than three-dimensional conformal RT, although not statistically different. Tooth extraction before RT significantly reduced ORN incidence, after adjusting the background factors using propensity score matching. Conclusion: In patients with oral or oropharyngeal cancer who underwent RT, periapical lesions, more than 50% loss of alveolar bone, and tooth extraction after RT significantly increased the risk for ORN. Infected tooth extraction before RT significantly reduced the risk.

Perioperative oral care can prevent surgical site infection after colorectal cancer surgery: A multicenter, retrospective study of 1,926 cases analyzed by propensity score matching.

BACKGROUND: Surgical site infection is a common postoperative complication of colorectal cancer surgery, and surgical site infection increases medical costs, prolongs hospitalization, and worsens long-term prognosis. Perioperative oral care has been reported to be effective in preventing postoperative pneumonia, although there are only a few reports on its effectiveness in preventing surgical site infection. This study aimed to determine the role of perioperative oral care in surgical site infection prevention after colorectal cancer surgery. METHODS: In this study, 1,926 patients with colorectal cancer from 8 institutions were enrolled; 808 patients (oral care group) received perioperative oral care at the hospital's dental clinic, and 1,118 (control group) did not receive perioperative oral care. The data were matched by propensity score to reduce bias. Ultimately, a total of 1,480 patients were included in the analysis. RESULTS: The incidence of surgical site infection was significantly lower in the oral care group than in the control group (8.4% vs 15.7%, P < .001). Multivariate logistic regression analysis revealed 4 independent risk factors for surgical site infection: low albumin level, rectal cancer, blood loss, and lack of perioperative oral care. Lack of perioperative oral care had an odds ratio of 2.100 (95% confidence interval 1.510-2.930, P < .001). CONCLUSION: These results suggest that perioperative oral care can reduce the incidence of surgical site infection after colorectal cancer resection. Perioperative oral care may have an important role in the future perioperative management of colorectal cancer as a safe and effective method of surgical site infection prevention, although further validation in prospective studies is needed.

Prevalence of and risk factors for postoperative complications after lower third molar extraction: A multicenter prospective observational study in Japan.

Lower third molar extraction is the most common surgical treatment among routine dental and oral surgical procedures. while the surgical procedures for lower third molar extraction are well established, the difficulty of tooth extraction and the frequency of postoperative complications differ depending on the patient's background. To establish a management protocol for the lower third molars, the prevalence of and risk factors for postoperative complications after lower third molar extraction were investigated in a large number of Japanese patients in a multicenter prospective study. During 6 consecutive months in 2020, 1826 lower third molar extractions were performed at the 20 participating institutions. The medical records of the patients were reviewed, and relevant data were extracted. The prevalence of and risk factors for postoperative complications were analyzed. The prevalence of postoperative complications after lower third molar extraction was 10.0%. Multivariate analysis indicated that age (≤32 vs >32, odds ratio [OR]: 1.428, 95% confidence interval [95% CI]: 1.040-1.962, P < .05), the radiographic anatomical relationship between the tooth roots and mandibular canal (overlapping of the roots and canal vs no close anatomical relationship between the roots and the superior border of the canal, OR: 2.078, 95% CI: 1.333-3.238, P < .01; overlapping of the roots and canal vs roots impinging on the superior border of the canal, OR: 1.599, 95% CI: 1.050-2.435, P < .05), and impaction depth according to the Pell and Gregory classification (position C vs position A, OR: 3.7622, 95% CI: 2.079-6.310, P < .001; position C vs position B, OR: 2.574, 95% CI: 1.574-4.210, P < .001) are significant independent risk factors for postoperative complications after lower third molar extraction. These results suggested that higher age and a deeply impacted tooth might be significant independent risk factors for postoperative complications after lower third molar extraction.