Izumi Yoshioka

Maxillary reconstruction using a bipedicled osteocutaneous scapula flap

When managing extensive maxillary defects it is difficult to provide a stable biomechanical frame for prostheses, and obturators are difficult to use. This study reviews cases involving angular branch artery pedicled scapular bone flaps (SBF) combined with or without latissimus dorsi musculocutaneous flap (LDMF). Between 2004 and 2007, four wide maxillary defects were repaired using the angular vascularized branch of the scapular bone. Tumor resection with immediate reconstruction using combined LDMF and angular artery pedicled SBF was used in 3 cases and angular artery pedicled SBF alone in 1 case. Follow up was 6 months to 2 years. Satisfactory results were obtained for facial contour, appearance, speech, deglutition and breathing. No donor site complications or restricted shoulder movements were detected. The only complication was a minor infection of one flap. This procedure is useful, functionally and aesthetically, for reconstruction of wide extensive maxillary defects as bone supplied by the angular branch has a wider arc of rotation in relation to skin flaps and has a longer pedicle length from the axillary artery, long enough to reach the maxilla. This procedure also benefits from the flexibility of the soft tissue pedicle, such as the latissimus dorsi, serratus anterior and fasciocutaneous flaps.

Postoperative skeletal stability and accuracy of a new combined Le Fort I and horseshoe osteotomy for superior repositioning of the maxilla

Postoperative skeletal stability and accuracy were evaluated in a combination of Le Fort I and horseshoe osteotomies for superior repositioning of maxilla in bi-maxillary surgeries in 19 consecutive patients. 9 underwent Le Fort I osteotomy alone (preoperative planned superior movement <3.5 mm). 10 underwent Le Fort I and horseshoe osteotomy (combination group) (preoperative planned superior movement >3.5 mm). The maxilla was osteotomized and fixed with 4 titanium Le Fort plates followed by bilateral sagittal split ramus osteotomy of the mandible, fixed with 2 semi-rigid titanium miniplates. Maxillomandibular fixation was performed for 1 week. Lateral cephalograms were obtained preoperatively, 1 week postoperatively, 3, 6, 12 months later. The changes in point A, point of maxillary tuberosity, and upper molar mesial cusp tip were examined. Discrepancy between the planned and measured superior movement of the maxilla in the Le Fort I and combination groups was 0.30 and 0.23 mm, respectively. The maxillae in both groups were repositioned close to their planned positions during surgery. 1 year later, both groups showed skeletal stability with no significant postoperative changes. When high superior repositioning of the maxilla is indicated, horseshoe osteotomy combined with Le Fort I is reliable and useful for accuracy and postoperative stability.

Predictability and accuracy of maxillary repositioning during bimaxillary surgery using a three-dimensional positioning technique

OBJECTIVE The purpose of this retrospective study was to evaluate the predictability and accuracy of maxillary repositioning during bimaxillary surgery using a three-dimensional positioning technique. STUDY DESIGN Twenty-six adult patients who underwent bimaxillary surgery requiring high superior maxillary impactions were divided into 2 groups. In group A, a three-dimensional positioning technique during maxillary repositioning was used along with an intermediate occlusal splint. In group B, only an intermediate occlusal splint with internal reference points was used. Both groups had measurements from predictive tracings compared to postoperative cephalograms to assess the accuracy of horizontal and vertical movements of the maxilla. RESULTS Group A showed excellent correlation between the planned and actual maxillary positions in vertical and horizontal dimensions. In group B, the maxilla tended to move anteriorly than planned. CONCLUSIONS Use of the three-dimensional positioning technique offered a predictive and accurate method for maxillary repositioning.

A spatial association between odontomas and the gubernaculum tracts

OBJECTIVES The purpose of this study was to identify the spatial relationship and/or association between odontomas and the gubernaculum tract or the dental sac and the characteristic findings for radiographic diagnosis of odontomas. STUDY DESIGN The visualizations of the odontomas and the gubernaculum tract were retrospectively analyzed using cone beam computed tomography or multidetector computed tomography. RESULTS Most of odontomas were within the gubernaculum tract or dental sac of unerupted permanent teeth on computed tomography. In some odontomas, the gubernaculum tract existed as a well-defined low density tract extending from the top of odontomas on computed tomography. CONCLUSIONS A close spatial relationship and/or association between odontomas and the gubernaculum tract or dental sac on computed tomography may be used as one of the criteria for radiographic diagnosis of odontomas. Development of odontomas may be associated with the gubernaculum tract or dental sac of unerupted permanent teeth.

CAD/CAM splint based on soft tissue 3D simulation for treatment of facial asymmetry

BackgroundMost cases of facial asymmetry involve yaw deformity, and determination of the yaw correction level is very difficult.MethodsWe use three-dimensional soft tissue simulation to determine the yaw correction level. This three-dimensional simulation is based on the addition of cephalometric prediction to gradual yaw correction. Optimal yaw correction is determined visually, and an intermediate splint is fabricated with computer-aided design and computer-aided manufacturing. Application of positioning devices and the performance of horseshoe osteotomy are advisable.ResultsWith this procedure, accurate repositioning of jaws was confirmed and patients obtained fairly good facial contour.ConclusionsThis procedure is a promising method for a widespread, predictable treatment of facial asymmetry.

Erratum to: Intraoperative detection of viable bone with fluorescence imaging using Visually Enhanced Lesion Scope in patients with bisphosphonate-related osteonecrosis of the jaw: clinical and pathological evaluation.

There is no standard surgical protocol of bisphosphonate-related osteonecrosis of the jaws (BRONJ), because of the impossibility to visualize this feature intraoperatively. The aim of this study was to introduce how to provide preoperative labeling of the viable bone with minocycline bone fluorescence technique (MBFT) by using VELscope® and investigate histopathologically. The American Association of Oral and Maxillofacial Surgeons (AAOMS) and the Japanese Society of Oral and Maxillofacial Surgeons (JSOMS) now recommend a more conservative treatment strategy. There is no standard surgical protocol of bisphosphonate-related osteonecrosis of the jaws (BRONJ) because of the impossibility to visualize this feature intraoperatively. The aim of this study was to introduce a mechanism providing preoperative labeling of a viable bone using minocycline bone fluorescence technique (MBFT) with VELscope® and to histopathologically investigate. This report describes a surgical technique used in six patients with BRONJ who underwent jawbone resection under minocycline bone fluorescence imaging using VELscope®. Subsequently, we investigated and compared the clinical findings using VELscope® and histopathological findings. Histopathological examinations showed that the non-fluorescent moiety was consistent with the BRONJ lesions. The surgical treatments that were exactly performed using MBFT with VELscope® offered successful management of BRONJ. This bone fluorescence helped to define the margins of resection, thus improving surgical therapy for extended osteonecrosis.

Detection and imaging characteristics of the gubernacular tract in children on cone beam and multidetector computed tomography

PURPOSE To elucidate the appearance and imaging characteristics of the gubernacular tract (GT) during the growth stage of children. Furthermore, this study evaluated the significance of the appearance of the GT. STUDY DESIGN The visualizations of the GT were retrospectively analyzed by using panoramic radiographs and computed tomography (CT) in children. RESULTS In patients with normal eruption who had unerupted permanent teeth, except maxillary central supernumerary teeth, the GT was clearly visualized as a well-defined low-density tract on CT but not on panoramic radiographs. In patients with obstructive eruption, including impaction, the GT was deformed and not visible on CT. CONCLUSIONS This paper describes the frequency of detection and appearance of the GT in unerupted teeth. Preliminary data suggest that any alteration to the GT may be used to predict abnormal eruption of permanent teeth.

Variety and complexity of fluorine-18-labelled fluoro-2-deoxy-d-glucose accumulations in the oral cavity of patients with oral cancers

OBJECTIVES To elucidate the points that require attention when interpreting fluorine-18-labelled fluoro-2-deoxy-d-glucose ((18)F-FDG)/positron emission tomography (PET) images by demonstration of (18)F-FDG accumulation in various areas of the oral cavity other than primary lesions in patients with oral cancers. METHODS (18)F-FDG accumulations with a maximal standardized uptake value of over 2.5 in various areas of the oral cavity other than primary lesions were identified in 82 patients with oral cancers. RESULTS (18)F-FDG/PET-positive areas, excluding primary tumours, included the front intrinsic muscles of the tongue (89.0%), upper and lower marginal parts of the orbicularis oris muscle (64.6%), sublingual glands, palatine tonsil, pharyngeal tonsil, and lingual tonsil. In addition, some areas in the jaws also showed accumulation. CONCLUSIONS In patients with oral cancers, areas of (18)F-FDG accumulation in the oral cavity should be precisely identified and appropriately diagnosed, because accumulations can be seen in areas other than the primary tumour.

Characteristics of the gubernaculum tracts in mesiodens and maxillary anterior teeth with delayed eruption on MDCT and CBCT

OBJECTIVES To elucidate the characteristics of the gubernaculum tracts (GTs) in maxillary anterior teeth with normal or delayed eruption and in mesiodens by using multidetector computed tomography and cone beam computed tomography. STUDY DESIGN The characteristics of GTs in maxillary anterior teeth of 205 patients with impacted mesiodens were retrospectively analyzed by using multidetector computed tomography and cone beam computed tomography. The GTs of teeth with normal or delayed eruption and the GTs of mesiodens were examined. RESULTS The detection ratio of GTs in impacted mesiodens and anterior teeth with delayed eruption was significantly lower than in teeth with normal eruption. A significant difference in the angulation was found between normal and delayed eruptions. Almost all detectable GTs in the inverted mesiodens were derived from the incisive canal, while the remaining were from the alveolar crest. The connecting area of major GTs to tooth in inverted mesiodens was the cervical or root area, but in all other anterior teeth, it was the crown area. CONCLUSIONS GTs of inverted mesiodens may exhibit characteristics that are different from those of normal GTs when the teeth and/or the palate are developing.

Efficacy and complications of submental tracheal intubation compared with tracheostomy in maxillofacial trauma patients.

Submental tracheal intubation is a technique for use in patients with maxillofacial trauma. The purpose of this retrospective study was to evaluate the efficacy and complications of this technique compared with tracheostomy. Twenty-five patients underwent submental tracheal intubation since 2001. Submental tracheal intubation was performed in cases needing intermaxillary fixation complicated by a nasal pyramid or anterior skull base fracture. No severe perioperative or long-term complications were noted. Intra- and postoperative complications were observed in three patients. In one case, the tube was accidentally dislodged into the right main bronchus during submental tracheal intubation. Two patients developed skin infections. Submental scarring was undetectable, except for one patient with slight scarring. Submental tracheal intubation avoids the complications associated with tracheostomy and the difficulty of nasal intubation during intubation and surgery. Therefore, submental tracheal intubation is useful in the intraoperative management of patients with complex maxillofacial trauma. (J Oral Sci 58, 23-28, 2016).