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.

Effect of Statins on Patients With Osteoradionecrosis of the Jaw.

BACKGROUND: Osteoradionecrosis of the jaw (ORN) is a late complication of radiation therapy. Radiation-induced fibrosis is the most likely mechanism for developing ORN, and statins are effective against radiation-induced fibrosis. However, no reports have indicated the direct effectiveness of statins in treating ORN. PURPOSE: This study aimed to measure the association between statin exposure and ORN disease resolution. STUDY DESIGN, SETTING, SAMPLE: This retrospective cohort study included patients with ORN diagnosed between January 2008 and December 2020 at the Hospital's Department of Oral and Maxillofacial Surgery. Patients who were immunocompromised or followed up for < 6 months were excluded. PREDICTOR VARIABLE: The predictor variable was statin exposure, which was defined as the use of statins for dyslipidemia. MAIN OUTCOME VARIABLE: The main outcome variable was ORN disease progression status (good prognosis). Patients who showed full recovery and improvement were included in the good prognosis group, and those who showed invariance and deterioration were included in the poor prognosis group. COVARIATES: We analyzed the clinicodemographic including the age of onset, sex, history of smoking, alcohol consumption, history of chemotherapy, tumor site, association with dental treatment, location (maxilla or mandible), the time to ORN onset from radiation therapy, and stage of ORN, and treatment characteristics including hyperbaric oxygen therapy, long-term macrolide administration, and sequestrectomy. ANALYSES: We analyzed the association between statin exposure or covariates and time to ORN improvement using bivariate and multivariate Cox regression. The significance level was set at P = .05. RESULTS: We analyzed 102 patients, and the improvement rate was 32.4%. The favorable prognostic factors were statin exposure (adjusted hazard ratio [HR], 3.71; 95% confidence interval [CI], 1.62 to 8.50; P = .002), onset in the maxilla (HR, 2.15; 95% CI, 1.02 to 4.55; P = .045), and stage 1 of ORN (HR, 2.65; 95% CI, 1.20 to 5.83; P = .016). CONCLUSION AND RELEVANCE: In this study, statin exposure, onset in the maxilla, and stage 1 of Lyons's classification were favorable prognostic factors for ORN. Although this study's findings were insufficient to recommend statin use for ORN, statins may be a novel and effective treatment for ORN.

Is the LRINEC score useful for predicting necrotizing fasciitis as a complication of MRONJ?

INTRODUCTION: Necrotizing fasciitis as a complication of medication-related osteonecrosis of the jaw (MRONJ), which we named "ONJ-NF", has been sometimes reported. This study aimed to investigate the usefulness of the Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) score for predicting ONJ-NF. MATERIALS AND METHODS: We included patients with acute MRONJ who required hospitalization at a single institution from April 2013 to June 2022. They were divided into two groups: patients with ONJ-NF and those with severe cellulitis as a complication of MRONJ, which we named "ONJ-SC." LRINEC scores were compared between the groups and the cut-off value of the score was set by creating a receiver operating characteristic curve. RESULTS: Eight patients with ONJ-NF and 22 patients with ONJ-SC were included. The LRINEC score was significantly higher in patients with ONJ-NF (median: 8.0 points, range 6-10 points) than in those with ONJ-SC (median: 2.5 points, range 0-6 points). A LRINEC score of ≥ 6 points had a sensitivity of 100.0%, a specificity of 77.3%, and an area under the curve of 0.97. Among 6 parameters of LRINEC score, only C-reactive protein (CRP) and white blood cell count (WBC) had significant differences between two groups. Most of the patients with ONJ-NF were rescued by antibiotic therapy and surgical drainage including debridement of necrotic tissues, but unfortunately, one patient did not survive. CONCLUSION: Our results suggested that the LRINEC score may be a useful diagnostic tool to predict ONJ-NF but valuating only CRP and WBC may be sufficient particularly in patients with osteoporosis.

Development of Cu application using dual-energy computed tomography for detecting medication-related osteonecrosis of the jaw.

INTRODUCTION: The present study developed an application using dual-energy computed tomography (DECT) focused on Cu for detecting medication-related osteonecrosis of the jaw (MRONJ). MATERIALS AND METHODS: First, we performed two types of phantom studies using a Cu wire syringe and pig mandible with Cu wire to detect Cu on DECT. Second, DECT examinations of 44 patients with MRONJ were performed to compare lesion and normal bone sites using single-energy CT, DECT-virtual non-calcium (VNCa), and DECT-Cu applications. Quantitative analyses of VNCa CT and CT values were performed, and a cut-off value was calculated using receiver operating characteristic analysis. Third, we compared the Cu content in the MRONJ and normal bone groups using inductively coupled plasma atomic emission spectroscopy (ICP-AES). RESULTS: The material-specific differences in attenuation between the two different energies enabled the accurate separation of Cu from Ca in phantom studies. The sensitivity and specificity for single-energy CT, DECT-VNCa, and DECT-Cu applications were 97.7% and 2.3%, 86.4% and 81.8%, and 88.6% and 97.7%, respectively. Thus, VNCa CT values obtained on DECT-Cu application images showed the highest area under the curve value and maximal diagnostic efficacy in differentiating lesion sites from normal bone sites. On ICP-AES analyses, the Cu content was significantly higher in the MRONJ group than in the normal bone group. CONCLUSION: DECT-Cu application demonstrated better diagnostic performance in detecting MRONJ compared with single-energy CT or DECT-VNCa.

A Novel Imaging Technique for Analyzing Condylar Movement During Mastication in Patients With Jaw Deformities: Four-Dimensional Computed Tomography.

OBJECTIVE: This study aimed to reveal characteristic condylar movements in patients with jaw deformities. STUDY DESIGN: Thirty patients with jaw deformities before surgery were enrolled and instructed to chew a cookie during 4-dimensional computed tomography (4DCT). The distance between the most anterior and posterior positions of the bilateral condyles on 4DCT images was measured and compared among patients with different skeletal classes. Correlations between the condylar protrusion and cephalometric values were also determined. RESULTS: The distances of condylar protrusion during mastication were significantly greater in the skeletal class II group than in the skeletal class III group ( P =0.0002). Significant correlations were found between the distances of condylar protrusion during mastication and the sella-nasion-B point angle ( r =-0.442, P =0.015), A point-nasion-B point angle ( r =0.516, P =0.004), sella-nasion plane to ramus plane angle ( r =0.464, P =0.01), sella-nasion plane to occlusal plane angle ( r =0.367, P =0.047), and condylion-gonion length ( r =-0.366, P =0.048). CONCLUSION: Motion analysis with 4DCT images revealed that condylar movement in patients with retrognathism was larger than in patients with mandibular prognathism. Skeletal structure was therefore correlated with condylar movement during mastication.

Hematologic and inflammatory parameters for determining severity of odontogenic infections at admission: a retrospective study.

BACKGROUND: Severe odontogenic infections in the head and neck region, especially necrotizing soft tissue infection (NSTI) and deep neck abscess, are potentially fatal due to their delayed diagnosis and treatment. Clinically, it is often difficult to distinguish NSTI and deep neck abscess in its early stage from cellulitis, and the decision to perform contrast-enhanced computed tomography imaging for detection is often a challenge. This retrospective case-control study aimed to examine the utility of routine blood tests as an adjunctive diagnostic tool for NSTI in the head and neck region and deep neck abscesses. METHODS: Patients with severe odontogenic infections in the head and neck region that required hospitalization were classified into four groups. At admission, hematologic and inflammatory parameters were calculated according to the blood test results. In addition, a decision tree analysis was performed to detect NSTI and deep neck abscesses. RESULTS: There were 271 patients, 45.4% in Group I (cellulitis), 22.5% in Group II (cellulitis with shallow abscess formation), 27.3% in Group III (deep neck abscess), and 4.8% in Group IV (NSTI). All hematologic and inflammatory parameters were higher in Groups III and IV. The Laboratory Risk Indicator for Necrotizing Fasciitis score, with a cut-off value of 6 and C-reactive protein (CRP) + the neutrophil-to-lymphocyte ratio (NLR), with a cut-off of 27, were remarkably useful for the exclusion diagnosis for Group IV. The decision tree analysis showed that the systemic immune-inflammation index (SII) of ≥ 282 or < 282 but with a CRP + NLR of ≥ 25 suggests Group III + IV and the classification accuracy was 89.3%. CONCLUSIONS: Hematologic and inflammatory parameters calculated using routine blood tests can be helpful as an adjunctive diagnostic tool in the early diagnosis of potentially fatal odontogenic infections. An SII of ≥ 282 or < 282 but with a CRP + NLR of ≥ 25 can be useful in the decision-making for performing contrast-enhanced computed tomography imaging.

Effects of a miconazole oral patch on preventing development of oral candidiasis in patients with head and neck cancer undergoing radiotherapy: results of a preliminary study quantifying the prevalence of Candida albicans in saliva.

PURPOSE: Serious oral mucositis develops during radiation therapy (RT) for head and neck cancer, but there is no effective preventive method. We have used a steroid ointment to prevent oral mucositis during RT, but the use of steroid ointment is discontinued when oral candidiasis develops. Therefore, prevention of oral candidiasis is important. The purpose of this study was to examine whether administration of a miconazole oral patch reduced the amount of Candida albicans in saliva and prevented the development of oral candidiasis during RT. METHODS: Participants were patients with head and neck cancer receiving RT ≥ 60 Gy. Patients in the intervention group received miconazole oral patches for 14 days after the appearance of grade 2 oral mucositis. The control group received oral care only. Total bacteria and C. albicans counts in the saliva were analyzed by real-time polymerase chain reaction. The incidence of oral candidiasis was compared between the groups. RESULTS: Total bacterial counts did not change throughout RT in either the intervention or the control group. However, C. albicans count significantly increased at 30 Gy and 60 Gy in the control group but was suppressed in the intervention group. The saliva pH did not show a significant change throughout RT in either group. The incidence of oral candidiasis in the intervention group tended to be lower than that in the control group. CONCLUSION: This study suggested that prophylactic use of a miconazole oral patch was effective in suppressing the growth of C. albicans count in saliva during RT for head and neck cancer.

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.

Success of dental implants in patients with large bone defect and analysis of risk factors for implant failure: a non-randomized retrospective cohort study.

OBJECTIVES: This study aimed to retrospectively investigate the success and survival rates of dental implants used for dentomaxillary prostheses at our hospital and the risk factors associated with large bone defects. MATERIALS AND METHODS: A total of 138 external joint system implants used for dentomaxillary prostheses in 40 patients with large bone defects were included in this study. The alveolar bone at the site of implant insertion was evaluated using panoramic radiography and computed tomography. Various risk factors (demographic characteristics, dental status, and operative factors such as the employment of alveolar bone augmentation, the site, the length, and diameter of implants) for implant failure and complete implant loss were investigated using univariate and multivariate analyses. The associations between the variables and the success and survival rates of dental implants were analyzed using the multivariate Cox proportional hazard models. RESULTS: The 10-year overall success and survival rates were 81.3% and 88.4% in this study. Multivariable analysis showed that the male sex (HR 6.22), shorter implants (≤ 8.5 mm) (HR 5.21), and bone augmentation (HR 2.58) were independent predictors of success rate. Bone augmentation (HR 5.14) and narrow implants (≤ 3.3 mm) (HR 3.86) were independent predictors of the survival rate. CONCLUSION: Male sex, shorter or narrow implants, and bone augmentation were independent risk factors for dental implants used in dentomaxillary prostheses in patients with large bone defects. CLINICAL RELEVANCE: Clinicians should consider these risk factors and pay close attention to the management of these patients.

Strategy for preventing skin paddle necrosis in mandibular reconstruction with free fibula osteocutaneous flap.

BACKGROUND: Non-thrombotic skin paddle necrosis occasionally occurs during mandibular reconstructions with free fibula osteocutaneous flaps. The number of perforators, size of the skin paddle, and ischemia time of the flap are considered as causes of skin paddle necrosis. The importance of donor side selection has also been highlighted. This study aimed to investigate the leading cause of skin paddle necrosis and the optimal reconstructive procedure. METHODS: A total of 66 patients who underwent mandibular reconstruction using a free fibula osteocutaneous flap were retrospectively analyzed. Skin paddle necrosis, number of cutaneous perforators, size of the skin paddle, and ischemia time of the flap were investigated. An incorrect "laterality" was defined as a skin paddle (septum) covering the reconstruction plate. Donor-site morbidity was recorded. RESULTS: Skin paddle necrosis occurred in 15.2% of patients. An incorrect laterality was associated with a higher incidence of skin paddle necrosis (odds ratio, 22.0; 95% confidence interval, 2.5-195; p = .005). Donor-site morbidity was noted in 18.8% of the patients, without any significant difference in terms of the donor side with and without skin graft (p = .592). The postoperative activities of daily living were not affected. CONCLUSIONS: To prevent skin paddle necrosis, donor side selection is an important safety strategy during mandibular reconstruction with free fibula osteocutaneous flap. The postoperative activities of daily living were found to be little affected by differences in the donor side.

Effects of preoperative dental examination and oral hygiene instruction on surgical site infection after hepatectomy: a retrospective study.

PURPOSE: This study retrospectively investigated relationships among risk factors and post-hepatectomy surgical site infection (SSI) and other complications in patients who underwent hepatectomy for hepatocellular carcinoma (HCC). METHODS: We included 334 patients who underwent hepatectomies for liver cancers between January 2011 and December 2015 in this study. We evaluated risk factors for SSI and other post-hepatectomy complication, including demographic factors, preoperative factors, and preoperative intervention including oral management, perioperative factors, and length of hospital stay, with univariate and multivariate analyses. The oral management intervention included self-care instructions, extraction of infected teeth, removal of dental plaques and calculus (scaling), professional mechanical teeth cleaning, removal of tongue coating, and cleaning of dentures. SSI was defined in accordance with the guideline issued by the Centers for Disease Control and Prevention; it included purulent discharge from any incision or organ space within 30 days postoperatively, with or without microbiological evidence. Complications of grade II or greater, according to the Clavien-Dindo classification, were regarded as postoperative complications. RESULTS: We found bacterial infection of ascites (Odds ratio (OR) = 13.72), lack of preoperative oral management intervention (OR = 10.17), and severe liver fibrosis (OR = 2.76) to be associated with SSI and severe liver fibrosis (OR = 2.28), hypoalbuminemia (OR = 2.02), blood transfusion (OR = 1.86), and longer operation time (OR = 1.80) to be associated with postoperative complications. CONCLUSIONS: Preoperative oral management may reduce the risk of SSI in patients with HCC who undergo hepatectomy.

Effect of educational intervention on the appropriate use of oral antimicrobials in oral and maxillofacial surgery: a retrospective secondary data analysis.

BACKGROUND: In Japan, oral third-generation cephalosporins with broad-spectrum activity are commonly prescribed in the practices of dentistry and oral surgery. However, there are few reports on the appropriate use of antibiotics in the field of oral surgery. This study aimed to evaluate the appropriateness of antibiotic use before and after an educational intervention in the Department of Oral and Maxillofacial Surgery, Kobe University Hospital. METHODS: The use of oral antibiotics was investigated among inpatients and outpatients before and after an educational intervention conducted by the antimicrobial stewardship team. Additionally, the frequency of surgical site infection after the surgical removal of an impacted third mandibular molar under general anesthesia and the prevalence of adverse effects of the prescribed antibiotics were comparatively evaluated between 2013 and 2018. RESULTS: After the educational intervention, a remarkable reduction was noted in the prescription of oral third-generation cephalosporins, but increased use of penicillins was noted among outpatients. There was reduced use of macrolides and quinolones in outpatients. Although a similar trend was seen for inpatients, the use of quinolones increased in this population. Despite the change in the pattern of antibiotic prescription, inpatients who underwent mandibular third molar extraction between 2013 and 2018 did not show a significant increase in the prevalence of surgical site infections (6.2% vs. 1.8%, p = .336) and adverse effects of drugs (2.1% vs. 0%, p = .466). CONCLUSIONS: This study suggests that the judicious use of oral antibiotics is possible through conscious and habitual practice of appropriate antibiotic use. However, further investigation is required to develop measures for appropriate use of oral antibiotics.

Tooth Loss Predicts Long-Term Prognosis of Esophageal Cancer After Esophagectomy.

BACKGROUND: Oral health is associated with various diseases, including cancer. Tooth loss is a simple and objective index of oral health. OBJECTIVE: The purpose of this study was to investigate the association between preoperative tooth loss and esophageal cancer prognosis after esophagectomy. METHODS: This study included 191 patients who underwent esophagectomy for esophageal cancer after perioperative dental evaluation and oral care at Kobe University Hospital from April 2011 to March 2016. Patients were divided into two groups: Group A (tooth loss < 7) and Group B (tooth loss ≥ 7). Three-year overall survival (OS) and multivariate analysis were performed, along with subgroup analysis for elderly patients (age ≥ 65 years). RESULTS: The 3-year OS rate was 68.1% in Group A (104 patients) and 49.2% in Group B (87 patients). Group A had significantly higher OS than Group B (p = 0.002), and there were no significant differences in sex and clinical T or N stage between the two groups. However, the mean age of Group A was younger than that of Group B (64.2 vs. 68.5 years; p = 0.0002). Among elderly patients, the 3-year OS rate was 68.2% in Group A (55 patients) and 45.1% in Group B (65 patients) [p = 0.003]. Multivariate analysis that included age demonstrated that tooth loss is an independent prognostic factor (hazard ratio 1.87, 95% confidence interval 1.22-2.87), in addition to clinical T stage and preoperative serum albumin. CONCLUSION: Tooth loss is an independent prognostic factor for esophageal cancer after esophagectomy.

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.

Does prophylactic antibiotic administration for tooth extraction affect PT-INR in patients taking warfarin?

BACKGROUND: Various antibiotics and analgesics have been reported to interact with warfarin. Reports that investigate the effects of medication taken for just a few days during tooth extraction on the prothrombin time-international normalized ratio are rare. METHODS: A total of 110 patients receiving long-term stable warfarin therapy underwent tooth extraction without interruption of warfarin treatment. INR values were measured 1 month before the tooth extraction, the day of the extraction, and 1 week after the extraction. We investigated the changes in INR values between the day of extraction and 1 week after extraction, as well as the various risk factors for increases in INR values. RESULTS: Before and after tooth extraction, the number of patients taking cefcapene pivoxil, amoxicillin, and azithromycin was 57, 36, and 8, respectively. Nine patients were administered ampicillin before tooth extraction and received amoxicillin after their tooth extraction. One week after tooth extraction, the INR values increased beyond the therapeutic range in 3 out of 110 patients (2.7%). The INR values before tooth extraction in these three patients were close to 3.0. The INR value increased by more than twice as much in 1 out of 110 patients (0.9%). CONCLUSION: Our results suggest that prophylactic antibiotic administration has little effect on INR values when patients on stable warfarin therapy undergo tooth extraction. Surgeons have to take attention if the patients whose INR values are close to 3.0 before their extraction.

Four-Dimensional Computed Tomography Evaluation of Condylar Movement in a Patient With Temporomandibular Joint Osteoarthritis.

Temporomandibular joint (TMJ) osteoarthritis (OA) is a disease of the bone, cartilage, and supporting tissues of the joint. Patients with advanced TMJ-OA often have symptoms such as pain, swelling, and joint dysfunction, and they sometimes require surgical intervention when conservative treatment is not effective. The etiology of TMJ-OA remains elusive. The usefulness of 4-dimensional (4D) computed tomography (CT) in motion analysis of various joints has recently been reported. This article introduces a novel imaging technique of 4D CT that aims to identify kinematic features that may be associated with the etiology of TMJ-OA. In a 69-year-old female patient with severe TMJ-OA, 4D CT evaluation of condylar movement was performed. During the scan, she was instructed to masticate a cookie normally and her natural condylar movement during mastication was evaluated. The coronal 4D CT motion images showed that the synovial cavity was narrower on the affected side than on the unaffected side. Repeated friction between the articular surface of the condyle and the caudal surface of the articular eminence was observed during natural mastication. Although friction between the condyle and articular eminence has been considered a factor in the initiation and progression of TMJ-OA in previous experimental studies using animals, this is the first study to directly visualize the friction between the atrophic and flattened condylar surface and the articular eminence. Four-dimensional CT is a novel imaging technique with the potential to assess kinematic features that cannot be visualized with other imaging modalities in patients with TMJ disease.

Delayed Socket Healing After Dental Extraction in Patients Undergoing Myelosuppressive Chemotherapy for Hematological Malignancy: Incidence and Risk Factors.

PURPOSE: The purpose of this study was to measure the frequency and identify factors associated with delayed socket healing after dental extraction in patients undergoing myelosuppressive chemotherapy for hematologic malignancy. MATERIALS AND METHODS: This prospective cohort study focused on delayed healing after extraction in patients with hematologic malignancy. Sockets with delayed healing were defined as those with intense pain and bone exposure 1 week postoperatively. Patients with and without delayed socket healing were compared using the Fisher exact test and Mann-Whitney U test with some variables. Receiver operating characteristics curve analysis was conducted to define cutoff values for delayed healing. RESULTS: One hundred ninety-four dental extractions in 93 patients (median age, 64 yr; range, 20 to 85 yr) were analyzed. The incidence of delayed socket healing was 7.5% (7 of 93 patients). There was no postoperative bleeding. Older age, type of hematologic malignancy (acute leukemia), shorter time from dental extraction to initiation of chemotherapy, low platelet count or hemoglobin level, requirement for red blood cell concentrate or platelet transfusion, and use of an absorbable hemostatic agent were statistically associated with the occurrence of delayed socket healing. Platelet and hemoglobin cutoffs were 4.6 × 104/µL and 7.7 g/dL, respectively. CONCLUSIONS: Although dental extraction can be safely performed in patients undergoing myelosuppressive chemotherapy for hematologic malignancy, oral surgeons should understand the potential risk for delayed socket healing. When considering dental extraction, patients with hematologic malignancy and low hemoglobin or platelet levels should be informed about the possibility of delayed socket healing.

Postradiotherapy Dental Implant Insertion Into Bone Grafts Harvested From Nonirradiated Tissue: Case Reports.

BACKGROUND: Prostheses and dental implants are often used to aid oral rehabilitation after surgery (with/without radiotherapy) for oral cancer. However, some studies have reported that the insertion of dental implants into irradiated bone results in a higher frequency of implant failure than the insertion of such implants in nonirradiated bone. MATERIALS AND METHODS: This report describes the cases of 4 patients with oral cancer who underwent surgery and radiotherapy (total dose: 50-86 Gy) and then had dental implants inserted within the irradiated area. In each case, an ilium bone graft or a latissimus dorsi myocutaneous flap containing scapular bone was transferred to the dental implant site before the insertion of the implants. RESULTS: Twenty-three implants were inserted. After loading, 2 implants were lost, and 21 remained stable. CONCLUSION: In patients who have undergone radiotherapy for oral cancer, transferring bone grafts harvested from nonirradiated tissue to the irradiated site before implant insertion might help to improve dental implant survival rates.

Long-term follow-up study of radial forearm free flap reconstruction after hemiglossectomy.

Previous studies on postoperative long-term results in patients who underwent reconstructive free flap transfer following hemiglossectomy had some issues, including the heterogeneity of the patient population and the observation period. The present study aimed to evaluate changes of reconstructed tongues in patients who underwent radial forearm free flap (RFFF) after hemiglossectomy with long-term follow-up. We enrolled 23 patients who underwent RFFF after hemiglossectomy with a postoperative follow-up of 5 years or more. Postoperative status (eating, speech, sensation function) was assessed by concise medical inquiries. Morphological changes of flaps were evaluated by reviewing clinical photographs. Hemiglossectomy involving the base of the tongue was performed in 4 cases (17.4%) and was limited to the mobile tongue in 19 cases (82.6%). The mean follow-up was 85.4 months (range, 60-122 months). All patients experienced gradually improved postoperative status. The most significant improvement was found between 1 and 5 years after surgery (P = 0.007), but not between 1 and 3 years (P = 0.075) or between 3 and 5 years (P = 0.530). In almost all of the flaps, there were few morphological changes throughout the follow-up period. Postoperative status in patients who underwent reconstructive RFFF following hemiglossectomy improved sequentially.

CT Evaluation of Morphology of Transferred Fibula for Implant Placement in Reconstructed Mandible.

BACKGROUND: Dental rehabilitation with osseointegrated implants in reconstructed mandibles remains one of the most challenging procedures for oral and maxillofacial surgeons. Satisfactory outcome requires appropriate assessment of graft morphology. There are few analyses of the morphology of fibulae in reconstructed mandibles, although cadaver studies on fibular shape have been performed. MATERIALS AND METHODS: In this study, we used postoperative computed tomography to retrospectively evaluate the shape, height, and orientation of fibulae transferred after mandibulectomy in 19 patients. RESULTS: The average height of transferred fibulae was 14.3 mm (range, 10.8-20.5 mm). The cross-sectional morphology of transferred fibulae could be classified into 2 types: apex and nonapex. The former type included knife-edged and triangular shapes; the latter included square and circular shapes. CONCLUSION: When implant insertion is planned in a reconstructed mandible, the orientation of the apex of transferred fibula should be evaluated preoperatively to allow for adjustments in implant procedure because the ridge at the apex of the fibula is narrow.