A Simple Method to Retract the Descending Palatine Neurovascular Bundle During Osseous Removal of Posterior Interferences in Le Fort I Osteotomy.

ABSTRACT: For accurate repositioning of the maxilla in Le Fort I osteotomy, bone removal around the descending palatine neurovascular bundle and maxillary tuberosity is frequently required. Such task can be challenging due to the high vascularity of the region, which is the most common site of hemorrhage during removal of bony interferences. Although a rare occurrence, ligation of the descending palatine artery in cases of intraoperative vascular damage can be related to the development of aseptic necrosis. This article reports a simple technique for retraction and protection of the descending palatine neurovascular bundle during bony removal related to a posterior maxillary impaction, which can be easily reproduced in orthognathic selected cases.

Assessment of the knowledge of canalis sinuosus amongst dentists and dental students: An online-based cross-sectional study.

INTRODUCTION: Canalis sinuosus (CS) is a neurovascular canal that corresponds to a small branch of the infraorbital canal. This study aimed at assessing the knowledge and detection performance of CS amongst dentists and dental students. MATERIALS AND METHODS: Four-hundred and five dentists and dental students answered a questionnaire with three parts: 1. Socio-demographical; 2. Clinical cases with cone- beam computed tomography (CBCT) sections showing CS and 3. Previous knowledge about CS. The chi-squared test and Spearman's correlation test were used to compare results as appropriate. p-values below .05 were considered statistically significant. RESULTS: Most participants did not identify CS in any CBCT. There was an association between the number of correct answers and dental specialties. Most individuals had not learned about CS previously. There was an association between past knowledge of CS and gender, highest academic degree, working environment, dental specialty and number of correct answers but not with age or experience in Dentistry. CONCLUSION: This study suggests that most dentists are not aware about CS and do not know how to diagnose it. Previous knowledge about CS positively influenced its identification in CBCT.

Vascularized Composite Parietal Bone Flap for Immediate Reconstruction of a Hemi-Maxillectomy Defect in an Infant.

BACKGROUND: Surgical resection of maxillary tumors can result in defects that can be difficult to reconstruct by conventional means due to the complex functional and anatomic nature of the midface and lack of regional bone flap options in the head and neck. Many reconstructive methods have been used to repair maxillary defects, but the ideal technique for the reconstruction of hemi-maxillectomy defects in growing pediatric patients has yet to be determined. METHODS: The authors present a rare pediatric patient with melanotic neuroectodermal tumor of infancy resulting in a hemi-maxillectomy defect after resection that was reconstructed using a pedicled vascularized composite flap consisting of temporalis muscle, pericranium, and parietal bone. RESULTS: The patient achieved successful long-term bony reconstruction of his right maxilla with this flap. Stable skeletal fixation with adequate orbital support was maintained over a >3-year follow-up period. CONCLUSION: A vascularized composite parietal bone flap is a reliable reconstructive option for reconstruction of large maxillectomy defects providing low donor-site morbidity, adequate globe support, excellent long-term skeletal stability, and malar symmetry in rapidly growing pediatric patients. Successful reconstruction for a rare patient with maxillary melanotic neuroectodermal tumor of infancy requiring hemi-maxillectomy was demonstrated with >3-year follow-up.

Course of the Maxillary Vein and its Positional Relationship With the Mandibular Ramus Require Attention During Mandibuloplasty.

PURPOSE: The maxillary vein is associated with major hemorrhage, an intraoperative risk factor during mandibuloplasty. Our objectives in this study were to identify the anatomical course of the maxillary vein relative to the mandible, and to ascertain the relationship of its course with that of the maxillary artery. METHODS: Thirteen sides of 13 cadavers in the possession of the Department of Anatomy of Tokyo Dental College were used. The maxillofacial region was first dissected, after which the upper part of the mandibular ramus was removed and the maxillary artery, maxillary vein, and pterygoid venous plexus were identified. The length of the maxillary vein and its height from the mandibular plane were then measured, and its anatomical course was recorded. RESULTS: The maxillary vein ran downward along the inner aspect of the temporal muscle, then from the base of the coronoid process it ran horizontally near the bone surface of the inner aspect of the mandibular ramus. After joining the inferior alveolar vein, it joined the superficial temporal vein to form the retromandibular vein. The mean length of the maxillary vein was 22.2 ±â€Š3.2 mm. At the posterior margin of the mandibular ramus, its mean height above the mandibular plane was 34.2 ±â€Š5.4 mm. From the posterior margin of the mandibular ramus to the lowest point of the mandibular notch, the maxillary vein was located within the areolar connective tissue directly above the periosteum adjoining the inner aspect of the mandibular ramus. CONCLUSIONS: In the wide area from the center of the maxillary notch to the posterior margin of the mandibular ramus, the maxillary vein runs extremely close to the periosteum on the inner aspect of the mandibular ramus, suggesting that it may pose a risk of hemorrhage in various oral surgical procedures.

Mirror Image Based Three-Dimensional Virtual Surgical Planning and Three-Dimensional Printing Guide System for the Reconstruction of Wide Maxilla Defect Using the Deep Circumflex Iliac Artery Free Flap.

A patient was diagnosed with squamous cell carcinoma of the maxillary sinus and consequently underwent a unilateral total maxillectomy and reconstruction using an anterolateral thigh (ALT) free flap. Soft tissue transplantation without a bone graft at the large maxillary defect site caused a midfacial collapse, which worsened, especially after radiotherapy. The 3-dimensional positioning of the composite flap for wide maxillary reconstruction is aesthetically important. To achieve ideal symmetry and aesthetics, a mirror image was created using the normal contralateral side. Through computer simulation, the function and symmetry of the virtually reconstructed maxilla was evaluated, and the surgical guide was made using a 3D printing system. Based on the prepared surgical guide, a deep circumflex iliac artery (DCIA) free flap was harvested, and its implementation in the reconstruction ultimately led to satisfactory results. Utilization of mirror image based virtual surgical planning and a 3D printing guide is a significantly effective method for maxilla reconstruction with DCIA flaps.

Distribution of the maxillary artery in the deep regions of the face and the maxilla: Clinical applications.

Composite tissue allotransplantation of the face has led to renewed interest in the vascularization of the maxilla. The maxillary artery, which is deep within the tissue and difficult to access, is considered the main artery of the maxilla. The objective of this study was to describe the distribution of the maxillary artery in the deep regions of the face and maxilla. Twenty-four maxillae were studied, of which 20 were injected with latex and four with India ink. The maxillary artery in the pterygopalatine fossa gave rise to the sphenopalatine artery, infraorbital artery, descending palatine artery, and posterior superior alveolar artery in all 24 cases. The posterior superior alveolar artery gave rise to a periosteal branch and an intraosseous branch (in the wall of the maxillary sinus) in 18 cases. The branch passed through part of the wall and the entire wall in eight and ten cases, respectively, and anastomosed at the anterior nasal spine and the infraorbital foramen. The descending palatine artery presented as a single trunk in four cases, a greater palatine artery and a lower palatine artery in 18 cases, and four branches in two cases. Intraosseous and periosteal anastomoses were found along with anastomosis through the incisive foramen, which were obstructed in three cases. The vascular territories were studied. The maxillary artery created an intraosseous and periosteal anastomotic network, explaining the supply pathways during different surgical procedures, risk of hemorrhage with orthognathic surgery (Le Fort type I) in a sinus lift for preimplant surgery, and the vascular territories.

Vascular malformation of the sphenoid and temporal bone: A diagnostic dilemma.

We present a rare case of a vascular anomaly of the sphenoid and temporal bones causing an expandable mass of the temporal region with dependent patient positioning and characteristic osseous changes on imaging. Initial diagnosis considerations included multiple myeloma (MM), fibrous dysplasia (FD), Paget's disease, lymphoma, meningoencephalocele (MEC), and vascular malformation (VaM). VaMs of the head and neck are rare and typically arise in the mandible and maxilla. However, this case demonstrates a unique finding of a VaM of the sphenoid and temporal bones with important radiological features to distinguish the diagnosis of vascular anomaly from other etiologies.

Contemporary CBCT diagnostics-discovery of a new artery with possible impact on surgical planning: the anterior superior palatal alveolar artery.

PURPOSE: An ongoing clinical trial regarding intra- and post-surgical morbidity in maxillary apicoectomies showed significant higher morbidity for upper canines and palatal roots of upper 1st premolars. Analysis of available presurgical cone beam computed tomography (CBCT)-scans revealed the existence of an unknown bone-canal branching off from the bone-canal or groove of the anterior superior alveolar artery (asaa). Aim of the study was the determination of the contents of this newly found bone canal in human cadaver heads, its prevalence as possible standard anatomical structure and its automatized detection with a contemporary high-resolution TRIUM-CBCT-device in vivo. METHODS: 35 human cadaver heads were dissected, the prevalence of the bone-canal determined and its contents analyzed by histology. 835 consecutive routine high-resolution TRIUM-CBCT-scans from routine patients were analyzed by an automatized detection- and tracing-algorithm for in vivo-determination of prevalence of this bone canal. Automatized detection and additional manual tracing were statistically evaluated by SSPS 20.0 software. RESULTS: The bone-canal was found in 96% of the anatomical specimens, its content identified as artery not described until now and named after the first finder "Arteria Kurrekii". Automatized tracing of TRIUM-CBCT-scans with additional manual tracing revealed an in vivo prevalence of this newly found artery of 95% (p ≤ 0.05). CONCLUSIONS: The newly found anterior superior palatal alveolar artery (aspaa-"Arteria Kurrekii") might have the same clinical impact for surgical procedures in the maxilla as the posterior superior alveolar artery (psaa). Its first detection was enabled by high-resolution TRIUM-CBCT devices and prevalence as standard anatomical structure proven in vivo by automatized CBCT-scan analysis.

Laser-Assisted Indocyanine Green Imaging for Assessment of Perioperative Maxillary Perfusion During Le Fort I Osteotomy: A Pilot Study.

PURPOSE: To determine the changes in maxillary perfusion during different stages of Le Fort I osteotomies as measured by laser-assisted indocyanine green imaging (LAICGI) and to determine whether various clinical factors affect maxillary vascular perfusion. MATERIALS AND METHODS: The medical records of those who had undergone Le Fort I osteotomy with LAICGI at the University of Illinois from 2016 to 2017 were reviewed retrospectively. The maxillary perfusion levels using LAICGI were measured before induction, after induction, after down fracture, after segmentalization (for segmental osteotomies), and after wound closure. The effects of clinical variables, including gender, race, American Society of Anesthesiologists physical status, type of Le Fort I osteotomy, intraoperative status of the descending palatine vessels, maxillary movements (anteroposterior, vertical, transverse), and hemodynamic data (mean arterial blood pressure, heart rate), were analyzed. RESULTS: Compared with the preoperative baseline values, the indocyanine green (ICG) levels decreased after down fracture and mobilization, segmentalization, and wound closure; no statistically significant differences were found among these 3 points. Segmentalization did not affect the ICG levels compared with the nonsegmentalized cases. Male gender and the amount of maxillary impaction were significantly associated statistically with decreased ICG levels, although the difference was not clinically significant. CONCLUSIONS: Compared with the baseline levels, maxillary perfusion, as measured by LAICGI, decreased from down fracture to wound closure. Segmentalization did not appear to influence maxillary perfusion, although male gender and impaction were associated with decreased perfusion. Because of its safety and convenience, LAICGI shows promise as a method of assessing maxillary perfusion in future largescale prospective studies linking perioperative perfusion to the occurrence of aseptic necrosis.

Anatomy of the Le Fort I segment: Are arterial variations a potential risk factor for avascular bone necrosis in Le Fort I osteotomies?

PURPOSE: Osteotomies of the Le Fort I segment are routine operations with low complication rates. Ischemic complications are rare, but can have severe consequences that may lead to avascular bone necrosis of the Le Fort I segment. Therefore the aim of this study was to investigate the blood supply and special arterial variants of the Le Fort I segment responsible for arterial hypoperfusion or ischemic avascular necrosis after surgery. MATERIAL AND METHODS: The arterial anatomy of the Le Fort I segment's blood supply using 30 halved human cadaver head specimens was analyzed after complete dissection until the submicroscopic level. In all specimens the arterial variants of the Le Fort I segment and also the arterial diameters measured at two points were evaluated. RESULTS: The typical known vascularization pattern was apparent in 90% of all specimens, in which the ascending palatine (D1: 1,2 mm ± 0,34 mm; D2: 0,8 mm ± 0,34 mm) and ascending pharyngeal artery (D1: 1,3 mm ± 0,58 mm; D2: <0,4 mm) were both supplying the Le Fort I segment. However in 10% of all specimens, the Le Fort I segment was dependent on the ascending pharyngeal artery alone and the missing ascending palatine artery was replaced with the anterior branch of the ascending pharyngeal artery (D1: 1,9 mm ± 0,32; D2: 1,0 mm ± 0,3 mm). CONCLUSION: This study is the first description of a special type of arterial variation of the Le Fort I segment. The type of this arterial variation, its clinical relevance and potential consequences are explained. Individuals with this special arterial anatomy may clinically be at a high risk for hypoperfusion and avascular segment necrosis after surgery. An individualized operation plan may prevent ischemic complications in at-risk patients.

Severe Delayed Hemorrhage After Cosmetic Rhinoplasty in the Setting of Maxillary Vascular Malformation.

Late epistaxis after rhinoplasty is a rare but potentially life-threatening occurrence. This case report concerns a 20-year-old woman who had severe epistaxis 5 and 10 days after a closed rhinoplasty with internal osteotomies and who ultimately required transcatheter arterial embolization for definitive control of the hemorrhagic source. Arterial hypervascularity, with signs of arteriovenous malformation, of the midface at the level of the piriform aperture and maxilla was seen on angiography.

Orthognathic Considerations of Vascular Malformations.

Vascular malformations affect the craniofacial skeleton in many ways, depending on the type of the lesion and its location. The lesions may exert a mass effect and cause thinning or thickening of the bone or cause expansion from direct bony infiltration. Orthognathic surgery can be used to correct any malocclusion or open bite deformities after the soft tissues are addressed.

Blood flow changes using a 3D xenogeneic collagen matrix or a subepithelial connective tissue graft for root coverage procedures: a pilot study.

BACKGROUND: The study investigated the early healing process following the treatment of single Miller class I and II recessions with a 3D xenogeneic collagen matrix (CMX) or connective tissue graft (CTG). METHODS: This pilot investigation was designed as a single-center randomized controlled parallel trial. A total of eight subjects (four per group) were treated with either CMX or CTG in the anterior maxilla. Vascular flow changes were assessed by laser Doppler flowmetry (LDF) before and after surgery and at days 1, 2, 3, 7, 14, and 30 while clinical evaluations took place at baseline and at days 60 and 180. Pain intensity perception was evaluated by the short-form McGill pain questionnaire (SF-MPQ), at days 1 and 14. RESULTS: The vascular flow fluctuated similarly in both groups pre- and post-operatively, but the CTG exhibited a more homogeneous pattern as opposed to CMX that showed a second phase of increased blood flow at 14 days. Clinically, the CTG led to greater change in mean root coverage and keratinized tissue gain but CMX was associated with lower early pain intensity scores. CONCLUSIONS: Within the limits of the study, the vascular flow alterations during the early healing of both graft types followed a similar pattern. The CMX was associated with a second peak of increased blood flow. CLINICAL RELEVANCE: The vascular flow changes after the application of CMX for single tooth recession root coverage did not show major differences from those observed after the use of a CTG. A trend for better clinical performance in terms of root coverage and keratinized tissue gain was noted for the CTG, but the initial patient morbidity was less for CMX.

Tomographic Evaluation of Prevalence, Position, and Diameter of the Intraosseous Branch of the Posterior Superior Alveolar Artery in Fully Edentulous Individuals.

The objective of this study was to evaluate the presence, position, and diameter of the intraosseous branch (IObr) of the posterior superior alveolar artery in fully edentulous patients. Two-hundred five computed tomography scans of fully edentulous patients were analyzed. The presence of the IObr was investigated in the coronal plane at the lateral wall of the maxillary sinus. In patients in whom the IObr was detected, the artery diameter was measured, and the distance from the artery to the bone crest of the alveolar ridge, the maxillary sinus floor, and the distance of the maxillary sinus floor to the bone crest of the alveolar ridge were measured as well. A descriptive statistical analysis of these parameters was conducted. The IObr was identified in the maxillary sinus in 105 tomography images (51.2%), and its diameter varied between 0.8 and 3.3 mm (1.29 ±â€Š0.49 mm). The IObr presented with an artery diameter less than 1 mm in 29% of the patients, between 1 and 2 mm diameter in 61% of the patients and with a diameter larger than 2 mm in 10% of patients. Regarding the IObr topography, the distance from the artery to the floor of the maxillary sinus was 9.62 ±â€Š4.59 mm, and the distance from the artery to the top of crestal bone was 15.15 ±â€Š4.47 mm. At least 10% of edentulous patients are at risk of bleeding complications during interventions in the maxillary sinus.

Assessment of accessory canals of the canalis sinuosus: a study of 1000 cone beam computed tomography examinations.

The aim of this study was to verify the presence, spatial location, and calibre of the accessory canals (AC) of the canalis sinuosus by cone beam computed tomography, and their relationship to the anterior maxilla. This retrospective analysis included the scans of 1000 subjects. Parameters registered were sex, age, number of AC, presence or absence of AC with a diameter <1.0mm, AC diameter (only for AC with a diameter >1.0mm), and AC location in relation to the adjacent teeth. Males showed a statistically higher frequency of AC than females. The difference in age distribution was not statistically significant. Twenty percent of all AC presented a diameter of a least 1.0mm. The end of the AC trajectory was most frequently located palatal to the anterior maxillary teeth. All relationships analyzed here were very weak (age vs. number of AC, age vs. AC diameter, number of AC vs. sex). Overall, the results of this study showed that AC of the canalis sinuosus are a common anatomical structure in the anterior maxilla, regardless of age and sex.

Treatment of the recanalization of maxillary and mandibular arteriovenous malformations in children.

OBJECTIVE: This study reviewed our experience in treating the recanalization of maxillary and mandibular arteriovenous malformations in children. STUDY DESIGN: Four patients with maxillary or mandibular arteriovenous malformations (AVMs) were included in this study. All the patients had undergone multidisciplinary treatment of AVM at least 26 months before our review, including superselective intra-arterial embolization combined with bone wax packing. Computed tomographic angiography and digital subtraction angiography were performed to confirm the presence of recanalization. Superselective intra-arterial embolization combined with bone wax packing and tooth extractions were performed in the patients with recanalization. RESULTS: After confirmation of the recanalization of AVM by digital subtraction angiography, the patients were treated with superselective intra-arterial embolization combined with bone wax packing and tooth extractions (if necessary). All the patients were followed up for 5 to 14 months, with an average of 9.5 months. The outcome for all patients was good, and no patient complained of pulsatile sensation or hemorrhage after treatment. CONCLUSIONS: In the treatment for recanalization of maxillary and mandibular AVMs, reapplication of the superselective intra-arterial embolization, combined with bone wax packing, remains necessary.

Changes in Maxillary Canine Pulpal Blood Flow During Dentoalveolar Distraction Osteogenesis.

OBJECTIVE: The aim of this study was to assess the effects of dentoalveolar distraction osteogenesis (DD) on the pulpal blood flow (PBF) of maxillary canines. MATERIALS AND METHODS: A laser Doppler flowmeter (LDF) was used to measure PBF in maxillary canines of 10 patients undergoing DD (study group) and 10 nonsurgical subjects who received no orthodontic treatment (control group). PBF was measured at baseline, at 4 and 7 days postoperatively, at the end of distraction and at the end of consolidation in the study group and at similar time-points in nonsurgical control subjects. Data were analyzed using paired and Student t tests, with the significance level set at 0.05. RESULTS: Study findings showed that baseline PBF values did not differ significantly between groups. PBF in the control group did not vary over time; however, in the study group, an initial decrease in PBF was observed at 4 days postoperatively and was followed by a gradual increase to preoperative levels at the end of distraction. CONCLUSIONS: During the DD latency period, there appears to be a short-lived ischemic phase when perfusion of pulp tissue declines; however, blood-flow returns to normal by the end of distraction.

Cleft Le Fort I Osteotomy: A Video Presentation.

In this video, we present a single piece Le Fort I osteotomy with bone graft in a patient with a unilateral cleft lip and palate. Maxillary osteotomies in the cleft patient can be challenging because of the presence of scar, palatal or alveolar fistulae, compromised teeth, and vascularization of the segments. The video demonstrates our current approach and technique. The authors particularly want to highlight aspects of the approach, such as the incision, exposure, osteotomies, mobilization, splints, and plating. The associated manuscript discusses the depicted video as well as the blood supply to the maxilla, and postoperative patient care.