Analgesic effect of a lidocaine-ropivacaine mixture for extraction of impacted mandibular third molars: a randomized controlled trial.

OBJECTIVES: The painless postoperative period can be significantly prolonged by using long-acting local anesthetics such as ropivacaine, though these local anesthetics are known for their slower onset of action. To compensate for this, a mixture of short-onset (e.g., lidocaine) and long-acting local anesthetics is used. However, the efficacy of such an anesthetic cocktail has not been elucidated in the field of oral and maxillofacial surgery. MATERIALS AND METHODS: To address the research purpose, this prospective randomized controlled trial included 56 patients scheduled for impacted mandibular third molar extraction. All patients received the inferior alveolar nerve block (IANB) using either 2% lidocaine with epinephrine or a 1:1 mixture of 2% lidocaine with epinephrine and 0.75% ropivacaine. RESULTS: Patients anesthetized using the lidocaine-ropivacaine mixture showed significantly prolonged postoperative analgesia and pain control than those anesthetized using lidocaine only. CONCLUSIONS: IANB using a lidocaine-ropivacaine mixture can provide prolonged postoperative anesthesia and pain control with extraction of mandibular third molars. CLINICAL RELEVANCE: This method can be a noteworthy addition to existing methods of local anesthesia for the extraction of mandibular third molars. Trial registration number University Hospital Medical Information Network (No. UMIN000044315).

Reconstruction After Hemimandibulectomy With a Plate and Soft-Tissue Free Flap Followed by a Titanium Mesh and Particulate Cancellous Bone and Marrow Harvested From Bilateral Posterior Ilia: A Case Report.

A particulate cancellous bone and marrow (PCBM) graft combined with titanium (Ti-) mesh tray has become one of the most popular mandibular reconstruction methods. The technique has been applied to the mandibular discontinuity defects after segmental mandibulectomy. To the best of our knowledge, there are no reports on using the technique after hemimandibulectomy, during which a wide mandibular resection, including the condyle, is performed. Here, we first report a case of mandibular reconstruction after hemimandibulectomy, using a plate and soft-tissue free flap, followed by a Ti-mesh and PCBM harvested from the bilateral posterior ilia, which was successful. This case report first revealed how bone resorption occurred clinically in mandibular reconstruction using PCBM and Ti-mesh tray after hemimandibulectomy. We also revealed the high predictability of the mandibular reconstruction using PCBM and Ti-mesh tray after hemimandibulectomy. Our report also provides a guiding principle to overcome the limitation of mandibular reconstruction using PCBM and Ti-mesh tray after hemimandibulectomy. However, our manuscript has limited evidence, being a case report.

Evaluation of effects of perioperative oral care intervention on hospitalization stay and postoperative infection in patients undergoing lung cancer intervention.

PURPOSE: This retrospective study investigated the effect of perioperative oral care intervention on postoperative outcomes in patients undergoing lung cancer resection, in terms of the length of postoperative hospital stay and the incidence of postoperative respiratory infections. METHODS: In total, 585 patients underwent lung resection for lung cancer, 397 received perioperative oral care intervention, whereas the remaining 188 did not. This study retrospectively investigated the demographic and clinical characteristics (including postoperative complications and postoperative hospital stay) of each group. To determine whether perioperative oral care intervention was independently associated with either postoperative hospital stay or postoperative respiratory infections, multivariate analysis, multiple regression analysis, and multivariate logistic regression analysis were conducted. RESULTS: Parameters significantly associated with a prolonged postoperative hospital stay in lung cancer surgery patients were older age, postoperative complications, increased intraoperative bleeding, more invasive operative approach (e.g., open surgery), and lack of perioperative oral care intervention (standard partial regression coefficient (ß) = 0.083, p = 0.027). Furthermore, older age and longer operative time were significant independent risk factors for the occurrence of postoperative respiratory infections. Lack of perioperative oral care intervention was a potential risk factor for the occurrence of postoperative respiratory infections, although not statistically significant (odds ratio = 2.448, 95% confidence interval = 0.966-6.204, p = 0.059). CONCLUSION: These results highlight the importance of perioperative oral care intervention prior to lung cancer surgery, in order to shorten postoperative hospital stay and reduce the risk of postoperative respiratory infections.

Evaluation of a Semi-Solidifying Liquid Formula for Nasogastric Tube Feeding After Oral and Maxillofacial Surgery.

PURPOSE: The aim of this retrospective study was to evaluate a semi-solidifying liquid formula for nasogastric tube (NGT) feeding after oral and maxillofacial surgery. MATERIALS AND METHODS: In total, 42 patients who underwent oral and maxillofacial surgery for malignant tumors, benign tumors, jaw reconstruction, or jaw fractures received postoperative NGT feeding for nutritional control between 2013 and 2019. Of these patients, 21 received a liquid diet (liquid group; administration rate, 100 mL/hour) and 21 received a semi-solidifying liquid formula (semisolid group [SSG]; administration rate, 400 mL/hour; Mermed Plus; Terumo, Tokyo, Japan). We retrospectively evaluated the complications of NGT feeding in both groups. RESULTS: During the course of NGT feeding, the incidence of abdominal pain (P = .022), rate of probiotic prescription for diarrhea (P = .012), and Bristol stool form scale score (P = .014) were significantly lower in the SSG than in the liquid group. The maximum defecation frequency per day was also lower in the SSG, although the difference was not significant (P = .069). CONCLUSIONS: Overall, the semi-solidifying formula was associated with a higher administration rate and a lower incidence of gastrointestinal complications. These findings will help oral and maxillofacial surgeons in the selection of appropriate diets for postoperative NGT feeding.

Comparison of Complications With Semisolid Versus Liquid Diet Via Nasogastric Feeding Tube After Orthognathic Surgery.

PURPOSE: The aim of this retrospective study was to compare the effectiveness of nasogastric tube (NGT) feeding of a semisolid diet versus a liquid diet after orthognathic surgery. PATIENTS AND METHODS: The orthognathic surgery patients were relatively young and generally healthy, without severe medical disease. Of the patients, 26 received liquid feeding (liquid diet group [LG], with an administration rate of 100 mL/hour), 30 received semisolid feeding at a high administration rate (semisolid diet-rapid administration group [SSRAG], 200 to 500 mL/hour), and 33 received semisolid feeding at a slower rate (semisolid diet-slow administration group [SSSAG], 100 mL/hour). We retrospectively investigated the complications of NGT feeding in each group. RESULTS: The incidence of diarrhea was clearly lower in the SSRAG than in the LG. Among patients with lower-gastrointestinal tract symptoms, stool form scale scores and maximum defecation frequency per day were significantly lower in the SSRAG than in the LG (P = .001 for both). Rapid administration of a semisolid diet via an NGT resulted in fewer complications and shorter feeding times for orthognathic surgery patients. CONCLUSIONS: The rapid administration of a semisolid diet via an NGT should decrease the complications of NGT feeding and improve the quality of the perioperative period for patients. The findings of this study will help clinicians select NGT diets for relatively young, healthy patients, such as orthognathic surgery patients.

Effect of timing of collection of salivary metabolomic biomarkers on oral cancer detection.

The aim of this study is to evaluate the effect of duration after meals for saliva collections for oral cancer detection using metabolomics. Saliva samples were collected from oral cancer patients (n = 22) and controls (n = 44). Saliva from cancer patients was collected 12 h after dinner, and 1.5 and 3.5 h after breakfast. Control subjects fasted >1.5 h prior to saliva collection. Hydrophilic metabolites were analyzed using capillary electrophoresis mass spectrometry. Levels of 51 metabolites differed significantly in controls vs. oral cancer patients at the 12-h fasting time point (P < 0.05). Fifteen and ten metabolites differed significantly at the 1.5- and 3.5-h time points, respectively. The area of under receiver operating characteristic curve for discriminating oral cancer patients from controls was greatest at the 12-h fasting time point. The collection time after meals affects levels of salivary metabolites for oral cancer screening. The 12-h fasting after dinner time point is optimal. This study contributes to design of saliva collection protocols for metabolomics-based biomarker discovery.

Functional and aesthetic rehabilitation with maxillary prosthesis supported by two zygomatic implants for maxillary defect resulting from cancer ablative surgery: a case report/technique article.

We report herein a case of functional and aesthetic rehabilitation with maxillary prosthesis supported by only two zygomatic implants for a patient with severe maxillary defect resulting from subtotal maxillectomy for malignant melanoma of the upper gingiva. A 76-year-old woman was referred to our facility with non-painful discoloration of the upper gingiva. After several examinations, a clinical diagnosis of malignant melanoma of the upper gingiva (cT3N1M0 stage IVA, American Joint Committee on Cancer) was made. Subtotal maxillectomy utilizing Le Fort I osteotomy and functional neck dissection were performed. A conventional resection denture was made and employed postoperatively, but was unable to be suitably retained due to insufficient residual maxillary structures. Six months after tumor resection, two zygomatic implants were inserted into bilateral zygomatic bones. Magnetic attachments were applied as a mechanism for attaching the implants and resection denture. After application of these implants, retention and stability of the prosthesis was considerably improved. The patient became able to eat a normal diet. From an aesthetic perspective, the depressed upper lip was also properly restored, leading to an acceptable facial appearance.

Solution structure of human P1•P2 heterodimer provides insights into the role of eukaryotic stalk in recruiting the ribosome-inactivating protein trichosanthin to the ribosome.

Lateral ribosomal stalk is responsible for binding and recruiting translation factors during protein synthesis. The eukaryotic stalk consists of one P0 protein with two copies of P1•P2 heterodimers to form a P0(P1•P2)2 pentameric P-complex. Here, we have solved the structure of full-length P1•P2 by nuclear magnetic resonance spectroscopy. P1 and P2 dimerize via their helical N-terminal domains, whereas the C-terminal tails of P1•P2 are unstructured and can extend up to ∼125 Šaway from the dimerization domains. (15)N relaxation study reveals that the C-terminal tails are flexible, having a much faster internal mobility than the N-terminal domains. Replacement of prokaryotic L10(L7/L12)4/L11 by eukaryotic P0(P1•P2)2/eL12 rendered Escherichia coli ribosome, which is insensitive to trichosanthin (TCS), susceptible to depurination by TCS and the C-terminal tail was found to be responsible for this depurination. Truncation and insertion studies showed that depurination of hybrid ribosome is dependent on the length of the proline-alanine rich hinge region within the C-terminal tail. All together, we propose a model that recruitment of TCS to the sarcin-ricin loop required the flexible C-terminal tail, and the proline-alanine rich hinge region lengthens this C-terminal tail, allowing the tail to sweep around the ribosome to recruit TCS.

Synergistic effect of zoledronate and compressive force suppresses proliferation and differentiation of human gingival fibroblasts.

We investigated the effects of zoledronate (ZA) and compressive force, separately and in combination, on the proliferation and differentiation of human gingival fibroblasts (HGFs) to verify the mechanism underlying medication-related osteonecrosis of the jaw (MRONJ). The addition of 100 µM ZA markedly inhibited cell proliferation. Expression of type I collagen, fibroblast growth factor 2, and connective tissue growth factor genes, was decreased by ZA and compressive force. Similar results were observed for collagen expression by using Sirius red staining. These results, together with clinical findings that MRONJ is more common in cases with excessive mechanical stress on the oral mucosa, suggest that bisphosphonates such as ZA and mechanical stress may act in conjunction as risk factors for the development of MRONJ by affecting homeostasis of the oral mucosal tissues, including HGFs.

Ultrasound-guided arthrocentesis for condylar head fracture: a technical report.

OBJECTIVES: Double puncture arthrocentesis (DPA) of the temporomandibular joint (TMD) is considered an effective preservative option for managing mandibular condylar head fractures. However, the procedure is commonly performed by a traditional "blind" method using anatomical characteristics. In the present study, an ultrasonography (US) device was applied for the treatment of a case with a fractured mandibular condyle. METHODS: A 79-year-old female was diagnosed right side condylar head fracture complaining pain of right TMD and reduced mouth opening range: inter-incisor distance of 20 mm. Since the fracture position was high and inoperable, the decision was made to perform DPA of the TMD. The US probe was positioned parallel and slightly oblique to the major axis of the mandibular ramus. Both the posterior and anterior insertions into the joint space were performed according to the axis mentioned above, which enabled the operator to visualize the entirety of the needle. RESULTS: The device offered safety and ensured accuracy by providing real-time visual aid to the surgeon. The procedure provided an early increase in the inter-incisor distance (31 mm) and pain relief. CONCLUSIONS: Hence, for the preservative treatment of mandibular condylar head fractures, based on the present study, we recommend US-guided arthrocentesis as a safe, feasible, and effective therapeutic option instead of the conventional "blind" method.

Clinical evaluation of bone quality of particulate cancellous bone and marrow, and implant prosthetic rehabilitation.

This study aimed to subjectively evaluate bone quality in the particulate cancellous bone and marrow (PCBM) graft area and to assess the survival rates of implants. A retrospective review was conducted based on patient age, sex, diagnosis, reconstructed site, number of implants, prosthetic type, and duration of follow-up. Images from computed tomography (CT) before implant insertion were obtained and used in this study. We selected a 4.0-mm diameter × 8.0-mm length region of interest in the implant placement area, and measured the CT attenuation value. No significant correlations were seen between CT attenuation values and implant survival rates in the maxilla and mandible. On the other hand, CT attenuation values and implant survival rates were significantly lower in patients with malignancy than in non-malignant cases. Placing implants in PCBM grafted bone requires a full understanding of bone quality before surgery and drilling to ensure primary stability, along with consideration of soft tissue management and maintenance programs.

Factors influencing delayed referral of oral cancer patients from family dentists to the core hospital.

Background/purpose: Most oral cancer (OC) cases are identified by family dentists in Japan. However, a significant number of patients with OC in Japan are referred to core hospitals at advanced stages. Therefore, identifying the factors that contribute to delayed referrals from family dentists to core hospitals is crucial for detecting OC in its earlier stages. The aim of this retrospective study was to identify the risk factors for referral delays from family dentists to core hospitals. Materials and methods: The study included 63 patients with OC who were referred by family dentists to the Yamagata University Hospital between 2010 and 2022. The clinical parameters related to referral delays were retrospectively investigated using letters of reference provided by the family dentists and patient charts. Backward multiple regression analysis was performed to identify the relationships between the length of referral delay and potential risk factors. Additionally, backward multivariate logistic regression analysis was performed to examine the independent association between referral delays of >4 weeks and several clinical parameters. Results: Multiple regression analysis revealed that misdiagnosis of malignant lesions by family dentists (P = 0.047) was significantly associated with longer referral delays. Additionally, misdiagnosis of malignant lesions by family dentists was also an independent risk factor for referral delays of >4 weeks (odds ratio, 10.387; P = 0.006). Conclusion: Misdiagnosis of malignant lesions by family dentists was a significant risk factor for referral delays from family dentists to core hospitals. Our results will motivate family dentists to improve their ability to diagnose OC.

Evaluation of radiographic characteristics and surgical removal of 147 mesiodens.

The aim of this study was to evaluate the radiographic characteristics and surgical removal of mesiodens among patients who had attended the Department of Dentistry, Oral and Maxillofacial-Plastic and Reconstructive Surgery of the Faculty of Medicine, Yamagata University. This study included 121 patients in the final analysis. We retrospectively reviewed medical records including patient age, sex, mesiodens number, direction, position, opportunity for detection, surgical approach and operating time. The 121 patients comprised 82 males and 39 females. Mean age was 7.6 ± 3.1 years (range, 4-35 years). The total number of mesiodens among these 121 patients was 147. Ninety-six patients had one mesiodens, 24 patients had two mesiodens and 1 patient had 3 mesiodens. Seventy-nine mesiodens were detected while taking X-rays for routine dental examination and/or orthodontic treatment at their family dental/orthodontic clinic. Mean operating time for removal of the 147 mesiodens was 32.2 ± 18.1 min. Among the 96 patients with one mesiodens, mean operating time for removal of the mesiodens was 30.7 ± 16.5 min. Operating time for removal of a mesiodens tended to be prolonged with increased distance from the alveolar crest. Early detection of mesiodens on routine radiographic check-ups and surgical planning considering patient age, crown direction, position of the mesiodens will contribute to improved treatment of mesiodens.

Measures of oral health-related quality of life in patients with bone graft and implant prosthetic rehabilitation at the anterior of mandible/maxilla among young and middle-aged adults: a retrospective pilot study.

OBJECTIVES: Dental implants are believed to contribute to improved masticatory function and oral health-related quality of life (OHRQOL), but the details remain unclear. The aim of this study was to evaluate the clinical outcomes of dental implant prosthetic rehabilitation after bone graft at the anterior mandible/maxilla based on OHRQOL, particularly in young and middle-aged patients. METHODS: This retrospective study included 11 patients who received bone grafts at the anterior mandible/maxilla and dental implant surgery. Chewing function score and OHRQOL (using the Oral Health Impact Profile-14 questionnaire) were evaluated before and after completion of an implant-retained bridge or removable implant-supported denture. RESULTS: Chewing function score tended to improve slightly after dental implant prosthetic rehabilitation, but none of the observed differences were significant. In the assessment of OHRQOL, relatively worse domain scores before completion of dental implant prosthetic rehabilitation were seen for Functional limitation, Psychological discomfort, and Psychological disability. Conversely, Social disability seemed relatively unaffected by tooth loss. All domain scores and total scores for items other than Physical disability and Social disability were significantly improved after completion of dental implant rehabilitation. CONCLUSIONS: Tooth loss in the anterior region may not significantly affect chewing function score, but can have a significant impact on OHRQOL. Bone grafts and dental implant prosthetic rehabilitation can resolve these problems, and the results of this study will benefit both patients and medical professionals in terms of treatment planning and informed consent.

Salivary metabolomics for oral leukoplakia with and without dysplasia.

PURPOSE: Oral leukoplakia (OL) is a common potentially malignant oral disorder. Therefore, there is a need for simple screening methods for OL before its transformation into oral cancer. Furthermore, because invasive open biopsy is the sole method to determine if an OL lesion is dysplastic, there is also a clinical need for non-invasive methods to differentiate dysplastic OL from non-dysplastic OL. This study aimed to identify salivary metabolites that can help differentiate patients with OL from healthy controls (HC) and also dysplastic OL from non-dysplastic OL. MATERIAL & METHODS: Whole unstimulated saliva samples were collected from patients with OL (n = 30) and HCs (n = 29). The OL group included nine patients with dysplastic OL and 20 with non-dysplastic OL. Hydrophilic metabolites in the saliva samples were comprehensively analyzed through capillary electrophoresis mass spectrometry. To evaluate the discrimination ability of a combination of multiple markers, a multiple logistic regression (MLR) model was developed to differentiate patients with OL from HCs and dysplastic OL from non-dysplastic OL. RESULTS: Twenty-eight metabolites were evidently different between patients with OL and HCs. Finally, three metabolites (guanine, carnitine, and N-acetylputrescine) were selected to develop the MLR model, which resulted in a high area under curve (AUC) of the receiver operating characteristic (ROC) to differentiate patients with OL from HCs (AUC = 0.946, p < 0.001, 95% confidential interval [CI] = 0.889- 1.000). Similarly, two metabolites were evidently different between patients with dysplastic and non-dysplastic OL. Finally, only one metabolite (7-methylguanine) was selected in the MLR model, which revealed a moderate discrimination ability for dysplastic and non-dysplastic OL (AUC = 0761, p = 0.027, 95% CI = 0.551-0.972). CONCLUSION: Our candidate salivary metabolites showed potential not only to discriminate OL from HC, but also to discriminate dysplastic OL from non-dysplastic OL.

Usefulness of powdered crown of mandibular first premolars in birth year estimation by radiocarbon dating.

BACKGROUND: Radiocarbon (14C), whose levels increased in the atmosphere between 1955 and 1963, accumulates in the enamel of human teeth only during the process of tooth formation and has been applied to estimate the birth year of unidentified corpses. However, enamel isolation from teeth is time-consuming and labor-intensive. Therefore, this study aimed to estimate the birth year using 14C in the crown of a single mandibular first premolar tooth. MATERIALS AND METHODS: Fourteen mandibular first premolars collected from forensic autopsies were analyzed. For nine teeth, each tooth was cut longitudinally: half of the tooth was enamel, and the other half was crown (1). For the other five teeth, the entire crown was used (2). Thereafter, the 14C concentration in each tooth was measured using accelerator mass spectrometry. RESULTS: The absolute error between the actual date of birth (DOB) and the estimated DOB was within the range of 1.0-8.8 years in the enamel of five teeth and 0.1-4.0 years in the crown halves of seven teeth (1). For the five teeth with entire crowns, the absolute errors ranged between 0.3 and 3.0 years (2). CONCLUSION: The absolute error of 14C-based year of birth estimation using the powdered crown of the mandibular first premolar teeth ranged between 0.1 and 4.0 years. Our method, which involves pulverizing an entire crown, eliminates the need for the equipment, time, and labor associated with enamel isolation. Therefore, 14C dating using powdered crowns of mandibular premolars can be useful for birth year estimation.

Anti-melanogenesis effect of Glechoma hederacea L. extract on B16 murine melanoma cells.

Glechoma hederacea L. (Labiatae) has been used in folk medicine to treat various ailments for centuries. We investigated the effects of G. hederacea extract on melanogenesis in B16 melanoma cells. It significantly reduced both the cellular melanin content and tyrosinase activity in a concentration-dependent manner. An MTT assay did not reveal any obvious cytotoxicity. Furthermore, we found that G. hederacea extract decreased tyrosinase and microphthalmia-associated transcription factor protein expression, but did not inhibit tyrosinase-related protein-1 and tyrosinase-related protein-2 expression. RT-PCR analysis indicated that the antimelanogenic effect of G. hederacea extract might be due to inhibition of tyrosinase gene transcription. Moreover, this effect is regulated via suppression of microphthalmia-associated transcription factor protein expression. Our data indicate that G. hederacea extract inhibits melanin synthesis in B16 melanoma cells but is not cytotoxic. Hence it might prove a useful therapeutic agent for treating hyperpigmentation and an effective component of whitening cosmetics.

Bone marrow space volume of the mandible influencing intraoperative blood loss in bilateral sagittal split osteotomy: A pilot Study.

The aim of this study was to investigate whether the bone marrow space volume of the mandible affects blood loss during bilateral sagittal split osteotomy (BSSO). Sixteen patients who underwent BSSO in our hospital were included in this study. Bone marrow space volume of the mandible was measured by analyzing images from computed tomography. Blood loss during BSSO was measured by weighing gauze, measuring suctioned blood, and adjusting for the volume of irrigation solution used during BSSO. Mean blood loss during BSSO for the 16 patients was 200.5 ml, and patients were divided into: Group I, with less than mean blood loss; and Group II, with greater than mean blood loss. Total bone marrow space volume was significantly greater in Group II (12,450.7 ± 2644.3 mm3) than in Group I (9130.3 ± 3005.8 mm3; P<0.05). A correlation between bone marrow space volume and blood loss during BSSO was suggested, and these results are beneficial for surgeons planning and preparing the orthognathic surgery.

A Cross-Sectional Survey on the Association between Dental Health Conditions and University Personality Inventory Scores among University Students: A Single-Center Study in Japan.

This study examined the association between dental health conditions and scores on the University Personality Inventory (UPI) among university students in Japan. Participants were freshmen at Yamagata University between 2010 and 2019. Dental check-ups, including dental caries, periodontal disease, malocclusion, and temporomandibular disorders (TMD), and mental health screening using the UPI were performed; 12,433 students were included in the final analysis. A logistic regression analysis was performed to confirm the association between dental health conditions and >30 UPI scores, which indicate the need to consult mental health professionals. Overall, students who required treatment for TMD had a 3.165-fold higher risk of >30 UPI scores (OR = 3.165, 95% CI = 1.710−5.857). Periodontal disease and TMD in male participants (periodontal disease: OR = 1.329, 95% CI = 1.108−1.595; TMD: OR = 3.014, 95% CI = 1.107−8.204) and TMD in female participants (OR = 2.938, 95% CI = 1.340−6.445) were significant risk factors for >30 UPI scores. Students requiring treatment for TMD were at risk of obtaining >30 UPI scores. Although our study has several limitations, students with subjective symptoms (e.g., disturbance in opening the mouth) should take the UPI test or in some cases consult mental health professionals.

Association between the duration of antibiotic prophylaxis and surgical site infection after orthognathic surgery in Japan.

PURPOSE: This study aimed to evaluate the risk factors for surgical site infection (SSI) after orthognathic surgery, focusing on the duration of prophylactic antibiotic administration in Japan. STUDY DESIGN: The study included 181 patients who underwent orthognathic surgery at the Department of Oral and Maxillofacial Surgery of Yamagata University Hospital between 2012 and 2021. The clinical parameters of SSI were retrospectively investigated using patient charts. Logistic regression analysis was used to estimate the odds ratios (ORs) with 95% confidence intervals (CIs) for risk factors for SSI after orthognathic surgery. RESULTS: Nineteen patients (10.5%) were complicated with SSI. Male sex (OR, 3.638; 95% CI, 1.316-10.058) and an antibiotic prophylaxis duration ≤3 days (OR, 12.718; 95% CI, 1.639-98.673) were independent risk factors for SSI after orthognathic surgery. CONCLUSION: Extended-term antibiotic prophylaxis was more effective for prevention of SSI after orthognathic surgery than short-term in this study.