Orthognathic Surgery in Patients With Von Willebrand's Disease: A Report of Four Cases and Literature Review.

Von Willebrand's disease (VWD), characterized by quantitatively or qualitatively abnormal von Willebrand factor (VWF), is the most common inherited bleeding disorder. There is limited evidence of treatment using orthognathic surgery in patients with VWD. This report focuses on four patients with VWD who underwent orthognathic surgery and received Factor VIII/VWF concentrates (Confact F) preoperatively. One patient with type 3 (severe) VWD underwent delayed extubation owing to laryngeal edema and exhibited epistaxis thereafter. No perioperative complications were observed in any of the other patients. Two of the four patients were diagnosed with VWD during preoperative screening. Most young adults do not experience general anesthesia and, therefore, may not have undergone blood tests at a hospital. Thus, preoperative screening and adoption of a multidisciplinary approach to orthognathic surgery is important in patients with bleeding disorders such as VWD. Close communication between anesthetists, surgeons, and hematologists is essential to ensure effective management during the perioperative period.

Characteristics and Risk Factors for the Fracture of One-Piece Implants.

Objective: The one-piece dental implant was originally designed to overcome the structural weaknesses of the two-piece implant. However, a fractured one-piece implant requires removal because the abutment cannot be repaired or replaced to support new prosthetic restorations. The aim of this study was to clarify the features and risk factors for fracture of the one-piece implant. Methods: This study was designed as a retrospective case series research. The subjects were patients who were treated for fractures of the one-piece implant at a clinic in Japan between 2012 and 2021. Fractures of the one-piece implant were diagnosed by cone-beam computed tomography, and the association between age and duration from implant placement to fracture was analyzed by one-way ANOVA followed by the Tukey test. Results: Eighteen patients and 20 one-piece implants (under 39 years: 5 patients and 6 implants; 40-59 years: 7 patients and 7 implants; over 60 years: 6 patients and 7 implants) had fractures in their one-piece implants. Of the fractured implants, 11 had a diameter of 3 mm, and 9 had a diameter of 4 mm. The mean durations up to implant fracture were 662 days in the younger group, 1467 days in the middle group, and 1239 days in older group, and the duration was significantly shorter in the younger group. In addition, 83.3% of fracture implants in the younger group were in the molar region. All fractures of the one-piece implants occurred under the bone margin. Two patients had torus mandibularis, and 1 patient was had bruxism. Conclusions: One-piece implants in younger patients that are located in the lower molar position are the most susceptible to implant fracture, and the fracture occurred under the bone margin in all cases.

Computed tomography evaluation of risk factors for an undesirable buccal split during sagittal split ramus osteotomy.

Sagittal split ramus osteotomy (SSRO) sometimes induces an irregular split pattern referred to as a bad split. We investigated the risk factors for bad splits in the buccal plate of the ramus during SSRO. Ramus morphology and bad splits in the buccal plate of the ramus were assessed using preoperative and postoperative computed tomography images. Of the 53 rami analyzed, 45 had a successful split, and 8 had a bad split in the buccal plate. Horizontal images at the height of the mandibular foramen showed that there were significant differences in the ratio of the forward thickness to the backward thickness of the ramus between patients with a successful split and those with a bad split. In addition, the distal region of the cortical bone tended to be thicker and the curve of the lateral region of the cortical bone tended to be smaller in the bad split group than in the good split group. These results indicated that a ramus shape in which the width becomes thinner towards the back frequently induces bad splits in the buccal plate of the ramus during SSRO, and more attention should be paid to patients who have rami of these shapes in future surgeries.

A Case of Orthognathic Surgery for Jaw Deformity in a Patient with Spinocerebellar Ataxia.

Spinocerebellar ataxia (SCA) is a progressive neurodegenerative disease that can cause various ataxia symptoms. Here we report a patient with spinocerebellar ataxia who underwent orthognathic surgery to correct a mandibular protrusion with facial asymmetry. A 33-year-old woman was admitted to our hospital for orthognathic surgery. She started preoperative orthodontic treatment after a diagnosis of mandibular protrusion with facial asymmetry. Two and a half years later, after completing preoperative orthodontic treatment, she returned to our hospital after being diagnosed with spinocerebellar ataxia. After discussing the risk of surgery with the anesthesiologist and neurologist, we elected to perform orthognathic surgery after the patient provided informed consent. Sagittal split ramus osteotomy and intraoral vertical ramus osteotomy were performed under general anesthesia, but no remarkable perioperative complications occurred. After a 3-year follow-up, the occlusion has remained stable, and no postoperative relapse occurred. Whether we should provide surgical treatment for SCA patients is controversial. However, when long-term predictions were considered, altering an occlusion could improve a patient's quality of life in the present case.

The Usefulness of Saturated Salt Solution Embalming Method for Oral Surgical Skills Training: A New Cadaveric Training Model for Bone Harvesting.

The purpose of this study was to assess the usefulness of saturated salt solution-embalmed cadavers for oral surgical skills training related to bone graft harvesting. Two half-day surgical skills training workshops were held at the Tokyo Medical University utilizing eight cadavers embalmed with the saturated salt solution. A total of 22 participants including oral surgeons, residents, and dentists attended the workshop. Surgical training consisted of six procedures related to intraoral and extraoral bone harvesting. The participants were surveyed to assess self-confidence levels for each surgical procedure before and after completion of each workshop. The Wilcoxon signed-rank test was used to compare the differences between each median score before and after the workshop. There were statistically significant increases in the self-assessed confidence scores in bone harvesting procedures for the zygomatic bone (P = 0.003), maxillary tuberosity (P = 0.002), and other sites (P < 0.001). The anatomical features of saturated salt solution-embalmed cadavers were also examined. The textures of the oral mucosa and skin were similar to those of living individuals. The structure of bone tissues was well-preserved and the hardness was realistic. Consequently, all procedures were performed with sufficient realism. The saturated salt solution method has a relatively low cost of preparation and storage, and almost no odor. The authors suggest that saturated salt solution-embalmed cadavers could provide a new model for oral surgical skills training in bone harvesting.

Long-term structural changes and outcomes of implants in particulate cellular bone and marrow reconstructed jawbone.

BACKGROUND: Association between long-term structural changes of grafted bone and outcomes of the implants is not clear. PURPOSE: Morphometrical measurements and implant success were analyzed in subjects of particulate cellular bone and marrow (PCBM) reconstruction of the jawbone. MATERIALS AND METHODS: Subjects were 30 implants in 13 patients from a series of 24 PCBM reconstruction cases. The cortical bone thickness and cancellous computed tomography (CT) radiodensity values were retrospectively analyzed from the CT data of 27 subjects. The cumulative success rate of the implants in the PCBM reconstructed cases (pure graft) was compared with that of 127 implants of 56 native bone cases and 42 implants of 28 bone augmentation (partial graft) cases. RESULTS: In areas of PCBM reconstruction, cancellous CT radiodensity values were significantly high immediately after the surgery, and subsequently the values became stable. Cortical thickness was significantly increased, but did not reach that of native bone. Implant success rates were statistically not different (P = 0.783) between the native bone (91.3%), the partially grafted bone (95.2%), and the PCBM reconstructed bone (93.3%). CONCLUSION: Implants in pure grafted bone are mainly supported by cancellous bone, because cortical thickness remained thin for a long period of time.

Indications of Potassium Titanyl Phosphate Laser Therapy for Slow-Flow Vascular Malformations in Oral Region.

BACKGROUND: Indications for laser therapy for slow-flow vascular malformations in the oral and maxillofacial regions have not been clearly documented. The authors aimed to estimate the frequency of resolution of slow-flow vascular malformations and to identify risk and prognostic factors associated with resolution in potassium titanyl phosphate (KTP) laser treatment. METHODS: This study was designed as a prospective cohort study. Patients who had diagnosed slow-flow vascular malformations were continuously assigned to receive KTP laser therapy. All patients had intralesional laser photocoagulation performed under local anesthesia. Administered power of the KTP laser was fixed at 2 watts throughout the procedure in all patients. The primary endpoint was to understand the frequency of resolution of slow-flow vascular malformations in KTP laser treatment. Secondary endpoints were: treatment outcomes based on lesion size; treatment outcomes based on location; treatment outcomes based on total energy in joules; types of complications. Treatment outcomes were judged by a clinical assessment as well as reduction in lesion size on magnetic resonance imaging. RESULTS: Data were obtained from 26 patients (9 men, 17 women) with 38 lesions. The average lesion size was 13.5 ±â€Š7.7 mm. Treatment outcomes based on lesion size showed that cure and regression were obtained in lesions less than 30 mm in size. However, lesions larger than 30 mm showed no response. Lesions in the tongue and lips showed higher cure rates than in other areas. Treatment outcomes based on administered total energy in joules showed that 68% of lesions were treated and responded well at less than 400 joules. Complication rate was relatively high in the buccal mucosal lesions. Immediate postoperative complications such as necrosis were more common in high-energy administration than in low-energy administration. CONCLUSION: Our results indicated that KTP laser therapy was effective for slow-flow vascular malformations less than 30 mm in size without significant side effects.

Evaluation of dental implants as a risk factor for the development of bisphosphonate-related osteonecrosis of the jaw in breast cancer patients.

It remains unclear whether dental implants are a risk factor for the development of bisphosphonate-related osteonecrosis of the jaw (BRONJ). We retrospectively evaluated the status of dental implants in patients given intravenous bisphosphonates (BPs) in a breast cancer cohort to elucidate the risk for BRONJ at the implant site. We established a BRONJ oral monitoring program for 247 breast cancer patients given intravenous BP in our institution. The 3-year cumulative incidence rate was determined. The systemic and local risk factors of 44 patients who completed comprehensive oral examinations were evaluated by logistic regression analysis. The 3-year cumulative incidence rate of the 247 patients was 0.074 % (8/247, 95 % CI 0.0081-0.014). In the 44 orally examined patients, 6 (13.6 %: 6/44) had dental implants. Of these 6 patients, 1 developed BRONJ at the implant site. There were no significant differences in the age, total BP treatment period, number of residual teeth, time of regular oral monitoring, oral hygiene level, or dental implant insertion. Although a case of ONJ was identified, dental implants which were inserted before intravenous BP administration were not a risk factor for the development of ONJ in breast cancer patients.

Characteristics of the early stages of intravenous bisphosphonate-related osteonecrosis of the jaw in patients with breast cancer.

OBJECTIVE: The clinical features of the early stages of bisphosphonate-related osteonecrosis of the jaw (BRONJ) in patients with breast cancer remain unclear. A retrospective cohort study was conducted of patients with breast cancer who received intravenous bisphosphonate (BP) treatment in a single center in order to clarify the status of the early stages of BRONJ. MATERIALS AND METHODS: A BRONJ oral monitoring program was established in 247 breast cancer patients given intravenous BP treatment at the institution. The differences in age, BP treatment period, number of remaining teeth, oral hygiene status, presence of regular oral monitoring and the existence of suspected BRONJ (stage 0) among eight BRONJ and 36 non-BRONJ subjects who completed oral examinations were then compared. RESULTS: BRONJ was observed in 0.4% of subjects on the first visit to the oral surgery clinic and in 3.2% of subjects during the follow-up period. Logistic regression analysis revealed that the odds ratio for identifying patients with BRONJ during follow-up by the presence of stage 0 at first visit was 24.0 (95% confidence interval [CI] = 3.6-161.7). The area under the receiver operating characteristic curve for identifying subjects with BRONJ by the presence of stage 0 was 0.82 (95% CI = 0.63-1.00). CONCLUSION: The results suggest that patients with stage 0 BRONJ on the first visit may progress to advanced BRONJ during the follow-up period. The oral monitoring program may contribute to the early detection of BRONJ.

A simple evaluation method for early detection of bisphosphonate-related osteonecrosis of the mandible using computed tomography.

OBJECTIVES: The aim of this study was to establish a simple method for the early detection of bisphosphonate-related osteonecrosis of the jaw (BRONJ) using computed tomography (CT). MATERIALS AND METHODS: CT images of the mandible were obtained from a total of 20 patients with BRONJ and 20 control subjects. BRONJ was classified into 2 groups, with bone exposure (Stage 1-3 BRONJ) or without (Stage 0 BRONJ). In each patient, 15 transaxial CT images were selected and 30 configured regions of interest (ROI) were identified. The ANOVA test was applied to test the relationship between the severity of systemic risk factors. RESULTS: Regarding the local status of the mandible, significant differences were observed among the Stage 0 BRONJ, Stage 1-3 BRONJ, non-BRONJ and control groups in the cancellous bone CT radiodensity values, but there were no significant differences between the Stage 0 and Stage 1-3 BRONJ groups. In the cortical bone widths, significant differences were observed only between BRONJ and the controls. CONCLUSIONS: Measuring cancellous bone CT radiodensity value has the potential to be a simple and quantitative method to detect the early stages of BRONJ.