Relationship Between the Posterior Superior Alveolar Artery and Maxillary Sinus Pathology: A Cone-Beam Computed Tomography Study.

PURPOSE: The purpose of the present study was to assess the relationship between the posterior superior alveolar artery (PSAA), which plays an important role in the maxillary sinus blood supply, and maxillary sinus pathologic entities using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: The CBCT data from 325 patients (650 sinuses), aged 18 to 55 years, who had been referred to the Department of Dentomaxillofacial Radiology from 2015 to 2017 were evaluated retrospectively. For the PSAA examination, the axial, coronal, and sagittal CBCT images were evaluated for detection of an osseous canal in the lateral wall of the maxillary sinus and the prevalence, position, and location of the canal. In addition, the presence of maxillary sinus pathologic features was analyzed, and the relationship with the PSAA was investigated. The relationship among the categorical variables was tested using the χ2 test. RESULTS: The study group consisted of 325 patients, including 155 men (47.7%) and 170 women (52.3%). The PSAA was observed in 80.6% of the patients. Of the detected PSAAs, 79.0% were bilateral and 21.0% were unilateral and 56.3% were intraosseous and 40.7% were submembranous. A significant positive correlation was detected between the presence of a PSAA and patient age (P < .05). The prevalence of sinus pathologic entities was 73.2% of all patients. The most common sinus pathologic finding was localized mucosal thickening (53.5%). A significant relationship was found between the presence of PSAA and maxillary sinus pathologic entities (P < .001). CONCLUSIONS: The presence of a PSAA might be a predisposing factor that increases the susceptibility to maxillary sinus pathologic entities. CBCT is an effective imaging method in the evaluation of the maxillary sinuses.

The potential clinical relevance of anatomical structures and variations of the maxillary sinus for planned sinus floor elevation procedures: A retrospective cone beam computed tomography study.

BACKGROUND: Complications arising from sinus floor elevation (SFE) with lateral approach surgery can be avoided by means of maxillary sinus examination in the preoperative period. PURPOSE: To investigate anatomical variations in the maxillary sinus by making use of cone beam computed tomography (CBCT) in terms of SFE with a lateral approach. MATERIALS AND METHODS: Two hundred twenty eight maxillary sinuses in 114 patients were included. Parameters such as the position and diameter of the posterior superior alveolar artery (PSAA) canal, the frequency and localization of the septa or accessory maxillary ostium (AMO), and lateral wall thickness values were subjected to statistical analysis. RESULTS: Septa were observed in 35.1% of sinuses. The majority of septa were determined in the middle region (48.8%). Additionally, 71.1% of PSAA canals were intraosseous, generally exceeding 1 mm in diameter (68.9%). The shortest mean perpendicular distance between the sinus floor and the PSAA canal was determined in the first molar region (9.22 ± 5.66 mm). Similarly, the highest mean sinus lateral wall thickness was determined in the first molar region, in the area 3 mm distant from the sinus floor (2.42 mm ± 0.88 mm). AMO was detected in 40.8% of sinuses. CONCLUSION: CBCT-guided treatment planning may be beneficial prior to SFE procedures in order to avoid surgical complications.

Cone Beam Computed Tomography Evaluation of the Artery in the Lateral Wall of the Maxillary Sinus: Retrospective Analysis of 602 Sinuses.

PURPOSE: This retrospective study evaluates the location of the arteries in the maxillary sinus, particularly in the middle portion, using cone beam computed tomography (CBCT) scans that can detect the lateral arteries with high reliability. METHODS: In this retrospective study, 2 experienced independent examiners evaluated 602 sinuses on CBCT scans. DISCUSSION: No significant correlation was found between the location of arteries and the patient's age, sex, or dentition. In 92.0% (P ≤ 0.001) of the sinuses, at least 1 arterial branch was detectable. CONCLUSION: Based on the CBCT scans, we found that a very high proportion of patients have the maxillary artery in their lateral sinus wall, which is important information for sinus augmentation or sinus surgery.

Vascular Precautions Before Sinus Lift Procedure.

The aim of the study was to evaluate the benefit of cone beam computed tomography (CBCT) and how to minimize injury to the posterior superior alveolar artery (PSAA) before sinus lift procedure. Cone beam computed tomography scans of 30 maxillary sinuses (15 patients) assessed to determine the location of PSAA presinus lift procedure. The data collected were used to extend the existed literature. The most common location of the PSAA was intraosseous (66.7%), the subantral distance mean was 5 ±â€Š1 mm, and the mean distance of PSAA from the crest was 15 ±â€Š1.6 mm. Cone beam computed tomography is valuable before the sinus lift procedure to exclude the presence of any lesion and to detect the location of the PSAA. The study recommends not to extend the upper border of the window beyond 16 mm from the residual crest during the lateral sinus approach.

[Detection and management of the vascular paths in the lateral sinus wall using cone beam computed tomography].

OBJECTIVE: To detect the vascular paths in the lateral wall of maxillary sinus using cone beam computer tomography (CBCT), and to retrospect the surgical managements of avoiding bleeding complication during the lateral approach maxillary sinus elevation. METHODS: The documents of 71 consecutive patients with 81 sides maxillary sinus elevation surgery were collected. The vascular paths in the lateral wall of maxillary sinus were detected by the preoperative CBCT, and the messages about the vascular in surgical records were analyzed. RESULTS: The paths of the vascular could be detected in 77 (95.1%) sides maxillary sinus in the reconstruction panoramic images of CBCT. At the position of the first molar, the paths of the vascular of the lateral maxillary sinus walls could be detected in 54 sides (66.7%) in the reconstruction coronal images of CBCT, and the other 27 sides (33.3%) could not be detected. Two approximately parallel paths of the vascular were found in 3 sides (3.7%) of the lateral maxillary sinus walls. The different diagnoses occurred in 6 sinuses between two observers. The kappa of diagnostic consistency of the two observers was 0.842 (P<0.001). The mean distance between the lower border of the vascular path to the plane of the alveolar crest of 54 sides maxillary sinuses was about (13.0±4.7) mm. The mean distance between lower border of vascular path to the plane of the floor of the sinus was (9.3±4.8) mm. The vascular path was located in the floor wall in 1 sinus. During the lateral approach maxillary sinus elevation operation, intraosseous vessels were dissected in 4 sides sinus lateral wall, the vascular path was avoided consciously in 3 sides, and the sinus elevation surgery had to be given up in 1 side for the vessel was torn and bleeding. There were no vascular related messages in 73 sides of the lateral approach maxillary sinus elevation operation records. CONCLUSION: The vascular paths of maxillary sinus wall could be detected by CBCT in most cases. Preoperative CBCT examination was proved to be reliable. The vascular paths of maxillary sinus wall should be examined carefully. It was helpful to make the surgical design perfectible and reduce the risk of tearing the vessel in operation.

Sinus presurgical evaluation: a literature review and a new classification proposal.

INTRODUCTION: Presurgical evaluation with cone beam computed tomography (CBCT) or computed tomography (CT) has become an essential tool for diagnosis and surgical planning, including maxillary sinus floor elevation. Before performing a sinus lift, the clinician's attention should not be only directed to the patency of the ostium through CBCT or CT, because many anatomical features could influence the surgical approach of sinus floor elevation. The goal of this article was to facilitate the communication between clinicians regarding the type of maxillary sinus, encourage in-depth analysis prior to surgery and reduce the risk of complications due to possible underestimation of important parameters. EVIDENCE ACQUISITION: An electronic search was conducted in Pubmed, Embase, Medline and Scopus, matching the following keywords: "sinus lift", "CBCT", "CT", "presurgical" and "evaluation". Clinical Oral Implant Research, Implant Dentistry, International Journal of Periodontics and Restorative Dentistry and Journal of Oral Implantology were hand-searched. The bibliographies of review articles were checked and personal references were also searched. EVIDENCE SYNTHESIS: Eleven parameters, that clinicians must check every time through CBCT or CT, were evaluated from different studies. At the end of the literature review for every single feature, the Authors established a favorable, a normal and an unfavorable situation, in order to provide a new classification. CONCLUSIONS: The grade of the described classification may be useful for clinicians to understand what probably the risk level of the sinus lift surgery could be and it may encourage the surgeon to have a careful pre-operative evaluation through CBCT or CT.

Radiographic Evaluation of Maxillary Sinus Lateral Wall and Posterior Superior Alveolar Artery Anatomy: A Cone-Beam Computed Tomographic Study.

OBJECTIVE: The purpose of the current study is to assess the thickness of the maxillary sinus lateral wall in dentate and edentulous patients using cone beam computed tomography (CBCT). This study also provides information about the diameter, prevalence, and course of the posterior superior alveolar artery (PSAA), and its relation to the maxillary sinus floor. MATERIALS AND METHODS: Four hundred and thirty CBCT scans of the maxillofacial complex (860 maxillary sinuses) were reviewed. Measurements of the lateral wall of the maxillary sinus and PSAA were performed on the CBCT images. RESULTS: Statistical analysis showed that dental status (edentulous, non-edentulous) of the patients had no significant effect on the lateral wall thickness. The mean thickness of the lateral wall of the maxillary sinus was 1.21 ± 1.07 mm at the second molar (M2), 1.98 ± 1.87 mm at the first molar (M1), 2.02 ± 1.53 mm at the second premolar (P2) and 2.16 ± 1.25 mm at the first premolar (P1). There was statistically significant difference between the left and right sides of the maxillary sinus only at P2 (p =.043). Detection rate of the PSAA on CBCT was reported as 60.58%. The mean diameter of the artery was 1.17 mm (range 0.4-2.8 mm). There was no significant correlation between age and the size of the PSAA. The most frequent path of the PSAA was intraosseous (69.6%), followed by intrasinusal (24.3%) and superficial (6.1%). The overall mean distance of the PSAA from the floor of the maxillary sinus is 8.16 mm. CONCLUSIONS: The results from this study suggest that using CBCT prior to the surgery provides valuable diagnostic information. However, undetected intraosseous canal in CBCT does not exclude its existence. Alteration in the lateral window design and the use of piezoelectric instruments are recommended if intraoperative complications are expected.

Preoperative 3D imaging in maxillary sinus: brief review of the literature and case report.

OBJECTIVE: The purpose of the present case report is to document the removal of a radix in antro without a hemorrhagic complication in presence of a posterior superior alveolar artery (PSAA) with a 2.8 mm diameter following a radiographic 3D planning by cone beam computed tomography (CBCT) scan. Furthermore, a brief literature overview on studies describing the existence and the variance of the PSAA is provided. METHOD AND MATERIALS: A foreign body removal in the right maxillary sinus was performed on a 33-year-old healthy man by using the lateral window osteotomy. The preoperative CBCT scan showed three arteries in the lateral maxillary sinus wall at a distance of 24.6 mm, 19.5 mm, and 13.5 mm to the alveolar crest. RESULTS: By removing a foreign body out of the maxillary sinus a vessel with a diameter of nearly 3 mm was exposed. Due to CBCT scan planning and the use of piezosurgery it was possible to avoid any damage to the vessel during the operation. The postoperative healing was uneventful and no complications occurred. CONCLUSION: Although laceration of vessels with a large diameter during lateral window osteotomy is not life-threatening it may compromise visualization and reduces the surgical outcome. Therefore, 3D imaging is recommended for the minimization of intra- and postoperative complications and for the localization of any foreign body in relation to other anatomical structures. This is of special interest in case of anatomical variances of blood vessels.

Verification of posterior superior alveolar artery distribution in lateral wall of maxillary sinus by location and defect pattern.

OBJECTIVE: Maxillary sinus augmentation is used when performing implant treatment in the maxillary molar region with inadequate bone height. Posterior superior alveolar artery (PSAA) is the branch of the maxillary artery that supplies the lateral sinus wall and sinus membrane. When performing an osteotomy via lateral approach, however, damage to the PSAA can occur, because it runs inside the lateral wall of the maxillary sinus, causing hemorrhage and hampering surgery. The objective of the present study was to compare the defect patterns with the distances from the alveolar crest and sinus floor to the PSAA. METHOD AND MATERIALS: 280 lateral regions in 235 patients with at least three missing consecutive posterior teeth were measured. Measurement locations were the 1st premolar (P1), the 2nd premolar (P2), the 1st molar (M1), and the 2nd molar (M2). RESULTS: The detection rate was 29% to 59%, and the longest diameter was between 1.1 mm and 1.3 mm. The average distances between the PSAA and the alveolar crest were 24.1 mm, 21.3 mm, 15.4 mm, and 15.3 mm (P1-M2), with statistically significant differences in all locations except M1 and M2. The average distances between the PSAA and the maxillary sinus floor were 10.4 mm, 10.4 mm, 9.0 mm, and 8.5 mm (P1-M2), with no significant differences. There were no significant differences between different defect patterns in the distance between the PSAA and either the alveolar crest or the maxillary sinus floor. PSAA detection rate and the longest diameter were related to the spatial resolution of the computed tomography (CT) scan. CONCLUSION: Although the distance between the PSAA and the alveolar crest was significantly shorter in the molar region than in the premolar region, it did not affect the defect pattern.

[Silent sinus syndrome (clinical case). New potential for enophthalmos correction].

Silent sinus syndrome (SSS) is a rare condition presenting with spontaneous enophthalmos and hypoglobus caused by volume reduction of maxillary sinus due to centripetal collapse of its walls. A case of SSS manifested during pregnancy in 43 years old patient is presented. In 16 months after manifestation of symptoms endoscopic sinus surgery was performed with no postoperative improvement of ocular symptoms. Intraorbital injection of stabilized hyaluronic acid gel was performed for correction of globe position. In control ultrasound examination color Doppler mapping revealed improvement of regional blood flow on the side of injection.

Synthetic bone substitute engineered with amniotic epithelial cells enhances bone regeneration after maxillary sinus augmentation.

BACKGROUND: Evidence has been provided that a cell-based therapy combined with the use of bioactive materials may significantly improve bone regeneration prior to dental implant, although the identification of an ideal source of progenitor/stem cells remains to be determined. AIM: In the present research, the bone regenerative property of an emerging source of progenitor cells, the amniotic epithelial cells (AEC), loaded on a calcium-phosphate synthetic bone substitute, made by direct rapid prototyping (rPT) technique, was evaluated in an animal study. MATERIAL AND METHODS: Two blocks of synthetic bone substitute (∼0.14 cm(3)), alone or engineered with 1×10(6) ovine AEC (oAEC), were grafted bilaterally into maxillary sinuses of six adult sheep, an animal model chosen for its high translational value in dentistry. The sheep were then randomly divided into two groups and sacrificed at 45 and 90 days post implantation (p.i.). Tissue regeneration was evaluated in the sinus explants by micro-computer tomography (micro-CT), morphological, morphometric and biochemical analyses. RESULTS AND CONCLUSIONS: The obtained data suggest that scaffold integration and bone deposition are positively influenced by allotransplantated oAEC. Sinus explants derived from sheep grafted with oAEC engineered scaffolds displayed a reduced fibrotic reaction, a limited inflammatory response and an accelerated process of angiogenesis. In addition, the presence of oAEC significantly stimulated osteogenesis either by enhancing bone deposition or making more extent the foci of bone nucleation. Besides the modulatory role played by oAEC in the crucial events successfully guiding tissue regeneration (angiogenesis, vascular endothelial growth factor expression and inflammation), data provided herein show that oAEC were also able to directly participate in the process of bone deposition, as suggested by the presence of oAEC entrapped within the newly deposited osteoid matrix and by their ability to switch-on the expression of a specific bone-related protein (osteocalcin, OCN) when transplanted into host tissues.

Insulin promotes bone formation in augmented maxillary sinus in diabetic rabbits.

The role of insulin during the formation of bone in the augmented space of the maxillary sinus in patients with diabetes is unclear. The authors compared the differences in bone formation after maxillary sinus floor elevation in diabetic and healthy animals and evaluated the effects of insulin on osteogenesis and the differentiation and activities of the osteoblasts. 10 male Japanese white rabbits were divided into two groups after diabetic induction by a single injection of monohydrated alloxan and having maintained steady blood glucose levels. The groups included the diabetes mellitus group (DM; n=5) and the DM+insulin group (n=5); another five healthy rabbits comprised the control group. Maxillary sinus floor elevation was performed by grafting hydroxyapatite particles. Compared with the control group, the newly formed bone area, number of blood vessels and osteoblasts, collagen I content and serum osteocalcin levels were significantly decreased in DM rabbits (P<0.01). Insulin treatment reversed the decrease in bone formation, blood vessels, osteoblasts, collagen I and serum osteocalcin (P<0.01). Insulin treatment also promoted osteogenesis in the augmented space of the diabetic rabbits, which might have resulted from promotion of osteoblast differentiation and upregulation of neovascularization.

Distributions of calcitonin gene-related peptide and substance P in the human maxillary sinus of Japanese cadavers.

BACKGROUND: Substance P (SP) and calcitonin gene-related peptide (CGRP) are released by the nociceptive sensory nerve and are involved in blood flow, pain and inflammation in the nasal mucosa. The purpose of this study was to assess the distribution of the SP and CGRP nerve fibres related to blood supply within human Schneiderian membrane of the maxillary sinus (MS). MATERIAL AND METHODS: In this study, the MS from Japanese cadavers was examined by whole-mount immunohistochemistry. Human male cadavers (ranging in age from 80 to 90 years) were used in this study. RESULTS: SP- and CGRP-positive fibres were found around large vessels of the medialis superior alveolar branches and also within the floor region of the MS. The floor region of the MS was composed of complex branches of these fibres. CONCLUSION: Our results give useful information for surgical sinus floor elevation in this region of the MS. These anatomical features may assist in the execution of a successful surgical procedure.

A radiographic study of the position and prevalence of the maxillary arterial endosseous anastomosis using cone beam computed tomography.

PURPOSE: This study was designed to investigate the prevalence and course of the vascular canals in the maxillary sinus walls and to measure the distance between the sinus floor, the edentulous alveolar crest, and the vascular canal using cone beam computed tomography (CBCT). MATERIALS AND METHODS: The maxillary sinus CBCT scans of 250 patients scheduled for implant surgery were examined. The vertical and mediolateral positions of the vascular canals or notches were investigated on the CBCT images. The location of each tooth was confirmed using a diagnostic template for implant placement. Statistical analyses were performed to verify whether the mean artery position was significantly different according to each tooth location, gender, and age. RESULTS: A maxillary arterial endosseous anastomosis was observed in 52.8% of patients. The mean perpendicular distance from the sinus floor to the vascular canal was shortest in the first molar region (7.58 ± 3.19 mm) and longest in the first premolar region (9.2 ± 3.22 mm). The mean distance from the alveolar crest to the vascular canal was shortest in the first molar region (14.79 ± 4.04 mm) and longest in the first premolar region (18.92 ± 4.86 mm). These distances were significantly different according to tooth position. The mean distances from the alveolar crest and the sinus floor to the vascular canal did not decrease with age. The mediolateral position of the canals was also significantly different depending on tooth position. CONCLUSION: With this information about the branch of the posterior superior alveolar artery from CBCT, unnecessary bleeding during implant placement should be more easily preventable. The use of CBCT is recommended as a routine procedure prior to sinus floor elevation.

A radiographic study of the posterior superior alveolar artery.

PURPOSE: The purpose of this study was to elucidate the differences of the prevalence and diameter of the posterior superior alveolar artery (PSAA) and the distance of its inferior border from the alveolar crest on computed tomography (CT) images according to age and sex. MATERIALS AND METHODS: CT images of maxilla in 200 patients were randomly selected from patients who underwent CT imaging at Yonsei University Dental Hospital, and analyzed. The prevalence of the PSAA in maxillary sinus and the distance of its inferior border from the alveolar crest in the premolar and molar area were measured. RESULTS: The average prevalence of the PSAA on CT images was 52.0%, and it is higher in males (64%) than in females (40%). The diameter of the PSAA was 1.52 ± 0.47 mm (mean ± SD), and larger in males. The distance from the PSAA to the alveolar crest was greater in the premolar area (18.90 ± 4.21 mm) than in the molar area (15.45 ± 4.04 mm), and it did not differ significantly with age or sex. CONCLUSIONS: The prevalence of the PSAA on CT images was higher, and the diameter was larger in males. The PSAA was more close to the alveolar crest in the molar areas. The evaluation of the PSAA in maxillary sinus on CT images before surgery could reduce the likelihood of excess bleeding during surgery especially in molar areas.

Onlay and inlay bone grafts with platelet-rich plasma: histologic evaluations from human biopsies.

PURPOSE: The aim of the present study was to histomorphometrically evaluate biopsies from 1) sinus inlay bone grafts prepared with or without platelet-rich plasma (PRP) and 2) onlay bone grafts in the anterior maxilla with particulate bone and PRP or block bone without PRP after 3 months. MATERIALS AND METHODS: Biopsies were retrieved with a trephine drill, and samples were processed in laboratories to result in nondecalcified cut and ground sections. Light microscopic measurements of total bone area, new bone, number of vessels, and vessel area were performed at 3 regions in each sample. Calculations of ratios of new bone to total bone and vessel area to total area were performed. RESULTS: There was a tendency toward higher mean values for total bone area percentage and area of newly formed bone in the PRP-treated inlay biopsies. However, there was no measurable effect on vessel formation in the PRP-treated inlay samples compared with untreated inlay samples. Particulate and PRP-treated onlay bone biopsies showed higher mean values in all measured parameters compared with block bone samples; however, no differences were statistically significant. CONCLUSION: PRP treatment may favor bone formation in grafted bone, and further research is needed to describe the outcome of PRP treatment and grafting techniques in the maxilla.

Maxillary sinus vascular anatomy and its relation to sinus lift surgery.

OBJECTIVES: To investigate the prevalence, location, size and course of the anastomosis between the dental branch of the posterior superior alveolar artery (PSAA), known as alveolar antral artery (AAA), and the infraorbital artery (IOA). MATERIAL AND METHODS: The first part of the study was performed on 30 maxillary sinuses deriving from 15 human cadaver heads. In order to visualize such anastomosis, the vascular network afferent to the sinus was injected with liquid latex mixed with green India ink through the external carotid artery. The second part of the study consisted of 100 CT scans from patients scheduled for sinus lift surgery. RESULTS: An anastomosis between the AAA and the IOA was found by dissection in the context of the sinus anterolateral wall in 100% of cases, while a well-defined bony canal was detected radiographically in 94 out of 200 sinuses (47% of cases). The mean vertical distance from the lowest point of this bony canal to the alveolar crest was 11.25 ± 2.99 mm (SD) in maxillae examined by CT. The canal diameter was <1 mm in 55.3% of cases, 1-2 mm in 40.4% of cases and 2-3 mm in 4.3% of cases. In 100% of cases, the AAA was found to be partially intra-osseous, that is between the Schneiderian membrane and the lateral bony wall of the sinus, in the area selected for sinus antrostomy. CONCLUSIONS: A sound knowledge of the maxillary sinus vascular anatomy and its careful analysis by CT scan is essential to prevent complications during surgical interventions involving this region.

Observing the bony canal structure of the human maxillary sinus in Japanese cadavers using cone beam CT.

We observed the location of the posterior superior alveolar artery (PSAA) and nerve at the macroscopic level between the maxillary sinus (MS) and surrounding bone of the anterior region of the maxilla. This study was completed using cone beam computed tomography (CBCT) imaging of 19 human cadavers with 38 sides of Japanese origin (ranging in age from 59-94 years, mean 77.7 +/- 9.8 years) that were prepared for this study. The bony canal structure of the inner surface of the maxilla was clearly apparent in our results, and the bony canals were classified into three types according to the structure along the course of the PSAA: canal-like, ditch-shaped tunnel and fragmented, and the lest sides were undefined. Calcitonin gene-related peptide (CGRP)-positive fibers were identified along the PSAA in the bony canal of the maxilla by immunohistochemistry. The presence of the bony structure and CGRP-positive nerve fibers along the PSAA suggests that there is risk to the PSAA during surgery involving graft implant in the floor of the maxillary sinus.

Palatal piezosurgical window osteotomy for maxillary sinus augmentation.

This technical note describes a new surgical technique for a palatal approach to the maxillary sinus for a vertical augmentation prior to dental implant placement. In 12 fully or partially edentulous patients (seven women, five men), 16 palatal sinus elevations were performed. After elevation of palatal full-thickness flap a rectangular access window was cut with a piezosurgical device. The raised sinus cavity was augmented with a synthetic nano-structured hydroxyapatite-based graft material. No harm occurred to the greater palatine artery or the sinus membrane. The vestibular and periimplant gingiva were preserved and there was no disharmonious soft tissue distortion or massive scar formation. Swelling and bleeding were minimal. Primary stability was achieved for all but one implant. This technique may be an alternative to other sinus augmentation approaches in cases where enough transversal width of the posterior alveolar crest is available.