Kazutoshi Nakaoka

Evaluation of 15 mandibular reconstructions with Dumbach Titan Mesh-System and particulate cancellous bone and marrow harvested from bilateral posterior ilia

This study reports on 15 mandibular reconstructions using the Dumbach Titan Mesh-System and particulate cancellous bone and marrow harvested from bilateral posterior ilia. All cases showed segmental defects. Eleven cases involved patients with malignant tumor. Six patients had received irradiation of 40-50 Gy. Reconstructions were performed immediately in 1 patient and secondarily in the remaining 14 patients. In 13 cases, mandibles were successfully reconstructed. Of these 13 patients, 9 reconstructions were completed without complications, whereas the other 4 cases showed complications. In 2 cases, reconstruction failed completely. Overall success rate was 87%. Statistical analysis revealed the extent of mandibular defect, but not malignancy of the original disease or radiotherapy of <or=50 Gy, as a significant factor in the occurrence of postoperative complications. Although no significant correlation was identified, cases in which mandibular continuity was lost at the time of reconstruction tended to show a higher postoperative complication rate. These results suggest that for the management of patients with malignant disease, resected mandible and soft tissue should be properly reconstructed using the metal plate and soft tissue flap at the time of cancer ablation surgery to reduce postreconstructive complications. Preoperative fabrication of the titanium mesh using a 3-dimensional skull model is expected to improve surgical outcomes.

Severity of arthroscopically observed pathology and levels of inflammatory cytokines in the synovial fluid before and after visually guided temporomandibular joint irrigation correlated with the clinical outcome in patients with chronic closed lock

OBJECTIVE This study aimed to investigate the severity of arthroscopically observed pathologies and the levels of a set of inflammatory cytokines in aspirated synovial fluid (A-SF) in patients with chronic closed lock (CCL) of the temporomandibular joint (TMJ) before and after visually guided TMJ irrigation (VGIR). Furthermore, the findings were correlated with the clinical outcome after VGIR. STUDY DESIGN VGIR was performed in 56 consecutive patients with unilateral CCL. Forty-nine of them, who underwent a second VGIR either as a follow-up arthroscopy or as a repeated therapeutic irrigation, were analyzed. They were assigned to either the successful (s-) group (n = 31) or unsuccessful (u-) group (n = 18), according to the clinical success criteria. The severity of arthroscopic findings of osteoarthritis (OA), synovitis, and fibrous adhesion (FA) were evaluated as arthroscopic scores. The levels of tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, IL-6, IL-8, IL-12, and IL-10 in the A-SF were measured. At the first and second VGIR, the arthroscopic scores and the levels of each investigated cytokine were compared between the s- and u-groups. In each group, same parameters were compared between the first and second VGIR. RESULTS At the first and second VGIR, there are no differences in the arthroscopic scores between the s- and u-groups. After the first VGIR, the severity of synovitis significantly improved, that of OA was unchanged, and that of FA became worse in the s- and u-groups. At the first VGIR, the levels of IL-6 and IL-8 were significantly higher in the u-group, and the IL-10 level was significantly higher in the s-group. At the second VGIR, however, there were no differences in the levels of each investigated cytokine between the s- and u-groups. The levels of each cytokine did not significantly change between the first and second VGIR, regardless of the clinical outcome. CONCLUSIONS VGIR may contribute to the remission of synovitis in patients with TMJ CCL. However, the severity of arthroscopically observed pathologies and the levels of each investigated cytokine do not seem to be reflected by the clinical state. Moreover even if the intra-articular inflammation is asymptomatic, an exacerbation may not be ruled out even after a successful VGIR.

Management of open bite that developed during treatment for internal derangement and osteoarthritis of the temporomandibular joint

This case report describes the orthodontic treatment performed for open bite caused by internal derangement (ID) and osteoarthritis (OA) of the temporomandibular joint (TMJ). A Japanese woman, aged 31 years and 11 months, referred to our department by an oral surgeon had an open bite with clockwise rotation of the mandible and degeneration of the condyle. The overbite was corrected through intrusion of the maxillary and mandibular molars using mini-screw implants to induce counterclockwise rotation of the mandible. Then, the mandibular second premolars were extracted and comprehensive orthodontic treatment was performed to establish a Class I molar relationship with distalization of the maxillary arch and to eliminate anterior crowding. Following treatment, her facial profile improved and a functional and stable occlusion was achieved without recurrence of the TMJ symptoms. These results suggest that orthodontic intrusion of the molars is one of the safer and less stressful alternatives for the management of open bite due to degeneration of the condyles caused by ID and OA of TMJ.

Magnetic resonance imaging findings and clinical symptoms in the temporomandibular joint in patients with mandibular continuity defects

PURPOSE This study explored the morphologic changes and clinical symptoms related to the temporomandibular joint (TMJ) associated with long-term lack of mandibular continuity. PATIENTS AND METHODS The subjects were 20 patients (40 TMJs) who underwent mandibulectomy including the condyle or segmental mandibulectomy without mandibular reconstruction more than 6 months previous to the study. The 40 TMJs were classified into the following 3 groups: group I: TMJs with a major mandibular fragment including the mandibular body (n = 21), group II: TMJs with a minor mandibular fragment including only the condylar process or the mandibular ramus (n = 10), and group III: TMJs without a condyle (n = 9). All TMJs were examined with respect to disc position, condylar position, bony changes, and appearance of joint effusion on magnetic resonance imaging, as well as for the presence of joint or muscle pain and joint noise. RESULTS The rate of anterior disc displacement was 28.6% in group I, 10.0% in group II, and 100% in group III. All condyles in group I were located in the glenoid fossa. Seven of 10 condyles in group II were dislocated anteriorly out of the glenoid fossa. However, these condyles were situated in the intermediate zone of the disc. Osteoarthritic changes was found in 1 joint in group II. Joint effusion was not observed in group I. However, joint effusion was detected in the posterior region of the upper joint compartment in 7 of 10 TMJs in group H and in 8 of 9 TMJs in group III. In group II, the 7 TMJs with joint effusion were the same joints with anteriorly dislocated condyles. Clinical symptoms of TMJ pain, TMJ noise, or muscular pain were not found in any patients. CONCLUSIONS Partial mandibulectomy does not affect the relationship between the disc and the condyle or the bony condition of the TMJ. The disc without a condyle will become anteriorly displaced with time. The condyle not connected to the mandibular body often dislocates anteriorly out of the glenoid fossa, while retaining a normal relationship with the disc. Joint effusion, which is detected in nonfunctional TMJs, is not associated with an inflammatory reaction in the joint compartment.

Mandibular reconstruction using custom-made titanium mesh tray and particulate cancellous bone and marrow harvested from bilateral posterior ilia

Abstract The objective of this study is to evaluate usefulness of mandibular reconstructions using a custom-made titanium mesh (Ti-mesh) tray and particulate cancellous bone and marrow (PCBM). A consecutive nine patients who underwent mandibular reconstruction were enrolled in this study. They were five men and four women (mean age: 53.9 years). Virtual reality simulation was performed using computer software based on the pre-operative computed tomography data. A 3-dimensional (3-D) skull model was constructed using a 3-D printer. A tray was custom-made from a Ti-mesh sheet bent to adapt to the model. After PCBM harvesting from bilateral posterior ilia, the tray was fixed to the host bone. New bone formation and configuration of the reconstructed mandible were assessed radiologically. Complications were recorded in each patient during the follow-up period. Patients, satisfaction with post-operative facial contour was evaluated using a visual analogue scale (VAS score, range = 0–100). In six of nine patients, excellent new bone formation was recognised and expected results were radiologically achieved. Complications occurred in four patients. These complications included Ti-mesh fracture, Ti-mesh exposure in the oral cavity, and delayed infection. Mean VAS score on patient satisfaction was 77.6. Although the data are preliminary, the results suggest that this method is clinically useful.

The levels of vascular endothelial growth factor in the synovial fluid correlated with the severity of arthroscopically observed synovitis and clinical outcome after temporomandibular joint irrigation in patients with chronic closed lock.

OBJECTIVE This study aimed to investigate the level of vascular endothelial growth factor (VEGF) in the temporomandibular joint (TMJ) synovial fluid (SF) and the severity of arthroscopically observed synovitis before and after visually guided TMJ irrigation (VGIR) in patients with chronic closed lock (CCL). In addition, the findings were correlated with the clinical outcome. STUDY DESIGN Twenty-four patients with unilateral CCL, who underwent a second VGIR either as a repeated therapeutic TMJ irrigation or as a follow-up arthroscopy, were enrolled in the study. They were divided into either successful (s-group; n = 11) and unsuccessful (u-group; n = 13) groups. The VEGF level in the aspirated SF and the severity of synovitis were compared between the s- and u-groups. In each group, the same parameters were compared before and after VGIR. The correlation of the VEGF level with the severity of synovitis was also studied. RESULTS At the first VGIR, the VEGF levels showed no significant differences when comparing s- and u-groups. At the second VGIR, the VEGF level was significantly higher in the u-group. The VEGF level significantly decreased after the first VGIR in the s-group but remained unchanged in the u-group. There was no significant correlation between the VEGF level and the severity of synovitis. CONCLUSIONS The level of VEGF in TMJ SF seems to reflect the clinical status in patients with CCL. Moreover, VEGF may be an important target molecule in future chemotherapy of TMJ CCL.

Solitary fibrous tumor of the buccal space resected in combination with coronoidectomy

Solitary fibrous tumor (SFT) is an uncommon spindle-cell mesenchymal tumor of probable fibroblastic derivation that most often occurs in the pleura, where it is typically benign. This report describes a case of a large SFT that arose in the buccal space, and includes computerized tomography, magnetic resonance imaging, and positron emission tomography (PET) findings. (18)F-Fluorodeoxyglucose (FDG) PET axial imaging showed weak abnormal accumulation of FDG in the left buccal region. The tumor was located behind the posterior wall of the maxilla, adjacent to the medial aspect of the coronoid process and was compressed between the coronoid and maxillary alveolar processes. We resected it with the use of a transoral approach in combination with coronoidectomy. Coronoidectomy was chosen because it facilitated safe removal of the tumor by improving its visibility and providing enough working space to resect it through a transoral approach.

The changes of joint effusion on MRI and arthroscopic findings after visually guided TMJ irrigation correlated to the clinical outcome

OBJECTIVE This study aimed to investigate the changes of joint effusion (JE) on the MRI and arthroscopically observed pathology after visually guided TMJ irrigation (VGIR) in patients with chronic closed lock. The correlation of these findings to the clinical outcome was also studied. STUDY DESIGN Forty patients with unilateral chronic closed lock who underwent 2-time VGIR, were divided into either the good outcome (g-) group (n = 29) or poor outcome (p-) group (n = 11) after the first VGIR. Before each VGIR, the each severity of JE, osteoarthritis, synovitis, and fibrous adhesion were assessed. They were compared between the g- and p-groups, or between the first and second VGIR. RESULTS The severity of JE at the first VGIR was significantly worse in the p-group. In both groups, JE significantly improved after the first VGIR. In the g-group, synovitis significantly improved after the first VGIR, but fibrous adhesion significantly became worse. CONCLUSIONS JE may be predictive for the clinical outcome of TMJ irrigation in chronic closed lock patients. Moreover, the severity of JE and arthroscopically observed synovitis could reflect the clinical state to some degree.

Solitary myofibroma of the mandible in an adult with magnetic resonance imaging and positron emission tomography findings: a case report

Myofibroma is a benign tumor composed of myoid spindle cells. The prevalence of myofibroma in the oral cavity is very low, with the mandible being the most common site. This report describes an adult case of myofibroma that arose on the mandible and includes magnetic resonance imaging (MRI) and positron emission tomography (PET) findings. On the MRI T1-weighted images, the tumor appeared with signal iso-intensity and was highly and heterogeneously enhanced with contrast material. On the T2-weighted images, it appeared with increased signal intensity. 18 F-fluorodeoxyglucose (FDG)-PET imaging showed abnormal strong accumulation of FDG in the left mandibular region. The tumor was removed by marginal resection of the left mandible under general anesthesia. Histopathological findings revealed that the tumor stroma contained abundant thin-walled vessels. The postoperative course was uneventful, and we found no evidence of recurrence at the postoperative 34-month follow-up.

Clinical Usefulness of Mandibular Reconstruction Using Custom-Made Titanium Mesh Tray and Autogenous Particulate Cancellous Bone and Marrow Harvested From Tibia and/or Ilia.

Abstract The objective of this study was to evaluate usefulness of mandibular reconstructions using custom-made titanium mesh (Ti-mesh) tray and particulate cancellous bone and marrow (PCBM). Consecutive 21 patients who underwent mandibular reconstruction were enrolled in this study. They were 13 men and 8 women (mean age, 52.0 years). Virtual reality simulation was performed using computer software based on the preoperative computed tomography data. A 3-dimensional skull model was constructed using 3-dimensional printer. A tray was custom-made from Ti-mesh sheet bent to adapt to the model. After PCBM harvesting from posterior ilia and/or proximal tibia, the tray was fixed to the host bone. New bone formation and configuration of the reconstructed mandible were assessed radiologically. Complications were recorded in each patient during the follow-up period. Patients’ satisfaction with postoperative facial contour was evaluated using visual analog scale (VAS score, range, 0–100). In 16 of 21 patients, excellent new bone formation was recognized and expected results were radiologically achieved. In 5 patients, new bone formation was insufficient. Causes of insufficient bone formation included postoperative infection in 2 patients, Ti-mesh tray fracture in 2 patients, and local recurrence of lower gingival cancer in 1 patient. To prevent a tray fracture, a double-layered Ti-mesh tray was useful. Mean VAS score on patients’ satisfaction was 77.1. Our results comprehensively suggest that mandibular reconstruction using custom-made Ti-mesh tray and PCBM is clinically useful.