Sinus membrane thickness of healthy endodontically treated maxillary molars.

OBJECTIVE: The study aimed to investigate the sinus membrane thickness (SMT) adjacent to healthy endodontically-treated maxillary molars with or without protruded apical foramen into the sinus cavity using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: Images of 207 non-smoker patients aged 18-40 were retrospectively analyzed, 140 were endodontically treated, and 136 were without endodontic treatment. Patients with any sinus pathology, teeth that have symptoms, or poor root filling were excluded. Study groups consisted of Group EM-I (endodontically treated and protruded apical foramen), Group EM-C (endodontically treated and contacted apical foramen), and similarly without endodontic treatment; Group M-I and Group M-C. SMT upon the mesial, distal, and palatal roots was measured. One-way ANOVA and Student's t-tests were performed. RESULTS: Group EM-I had the thickest sinus membrane compared to other groups (p = 0.013). SMT values were 2.37-2.60 mm in Group EM-I, and 1.34-1.58 mm in other groups. Thickening (> 2 mm) percentages were 33.45% in Group EM-I and between 4.25 and 8.25% in other groups. No statistical difference was detected between first and second molars and genders (p > 0.05). CONCLUSION: When the apical foramen protruded into the sinus cavity, the conventional root canal treatment caused a minimal (between 2.37 mm and 2.60 mm) sinus membrane thickening with a rate of 33.45% based upon CBCT examinations.

Anatomic relationship between the root apex of maxillary molars and maxillary sinus in the presence of antagonist teeth: A Kwak's method with divisions.

OBJECTIVE: The purpose of the study was to evaluate the proximity between the root apices of maxillary molars and maxillary sinus floor using cone-beam computed tomography (CBCT) in the southern Turkish subpopulation. DESIGN: For the study, 246 CBCT images were analyzed. The absence of antagonist teeth was excluded. Kwak's types III and V were detailed with three divisions. Division M; the penetration of the mesial root only, Division D; the penetration of the distal root only, and Division MD; the penetration of both buccal roots. The distance between the maxillary sinus and the root apices was measured. Student's t-test, one-way ANOVA, and chi-square were used for statistical analysis. RESULTS: The penetration of maxillary molars was 24.40%. The highest prevalence belonging to Type I. Division MD was 44.35% for Type III and 40.42% for Type V. Division M was higher than Division D. The distances between the sinus and root apices were 1.35-2.41 mm in Type I. The distance decreased with age (p < 0.05). CONCLUSION: Both buccal root penetration into the sinus was higher than the single root penetration. The distance of the second molar root apices to the sinus was closer than the first molar. One-quarter of the first and second molars were inside the sinus. A greater likelihood of penetration of the root apices into the sinus with increased age.

Anatomical Possibilities of the Alveolar Bone at the Upper Second Premolar Level.

Background and Objectives: The upper posterior teeth are typically regarded as being exclusively inferior to the maxillary sinus (MS). The expansion of the nasal fossa above the maxillary alveolar base (MAB) needs better investigation. The hypothesis was raised that the MAB in the upper premolar region, which is usually addressed by surgeons for the elevation of the antral floor, is not exclusively beneath the MS. Therefore, we aimed to document the possible upper relations of the MAB as antral, nasal, or both. Materials and Methods: A total of 145 CBCT scans were used to study four types of MAB: type 1-antral; type 2-antral with a palatal recess; type 3-antral and nasal; type 4-nasal. In type 2, the orthoradial width of the alveolar bone, the rectilinear width of the antral floor, and the maximum depth of the palatal recess were measured. For type 3, the MAB width and the straight widths of the antral and nasal segments of the MAB were measured. Results: Type 1 was found in 67.24%, type 2 in 13.45%, type 3 in 16.21%, and type 4 in 3.1% of the 290 MSs investigated. Palatal recesses were found in 11.72% of the MSs on the right side and 15.17% of the MSs on the left side. Types 1 and 2 exhibited strongly statistically significant bilateral symmetry (Pearson's Chi2 = 86.42, p < 0.001). Type 3 correlated equally with contralateral types 1 and 3. The bilateral symmetry for types 1-3 was stronger in the males (Pearson's Chi2 = 47.83, p < 0.001) than in the females (Pearson's Chi2 = 56.96, p < 0.001). There were no statistically significant associations between sex and the unilateral anatomical type. Conclusions: The MAB in the upper second premolar area should not be considered to be exclusively antral during surgeries or in anatomical teaching.

The comparison of visibility of the maxillary sinus septa between cone-beam computed tomography scans and panoramic radiograph images as dependent on the cortical bone thickness: a retrospective comparative study.

PURPOSE: To analyze the visibility of the maxillary sinus septa (MSS) in panoramic radiography (PR) versus cone beam computed tomography (CBCT) and to investigate whether the buccal cortical bone thickness (BT) or the septa dimensions influence their visibility. METHODS: Corresponding PR and CBCT images of 355 patients were selected and examined for MSS visibility. The septa dimensions (width, height, depth) and the BT were measured. Results were analysed statistically. RESULTS: Comparing the corresponding regions on CBCT and PR, 170 MSS were identified; however, only 106 of these were also visible using PR. The MSS visibility was significantly higher on CBCT versus PR images (P1: p = 0.039, P2: p = 0.015, M1: p = 0.041, M2: p = 0.017, M3: p = 0.000), except region C (p = 0.625). Regarding the measurements of MSS dimensions, only the height in region M1 (p = 0.013) and the width in region P2 (p = 0.034) were significantly more visible on CBCT. The BT in the area of the MSS was found to have a marginal influence on its visibility on the PR images only in regions M3 and M1 (M3: p = 0.043, M1: p = 0.047). In terms of MSS visibility based on the dimensions, significance was found for all three influencing variables only in region P2 (width; p = 0.041, height; p = 0.001, depth; p = 0.007). There were only isolated cases of further significance: M3 for width (p = 0.043), M2 for height (p = 0.024), and P1 for depth (p = 0.034), no further significance was noted. CONCLUSION: MSS visibility appears significantly higher on CBCT versus PR images. It is concluded that the septa dimensions and BT can influence MSS visibility on PR images just in certain regions.

Infraorbital canal variants and its clinical and surgical implications. A systematic review.

BACKGROUND: Recent literature highlights anomalous cranial nerves in the sinonasal region, notably in the sphenoid and maxillary sinuses, linked to anatomical factors. However, data on the suspended infraorbital canal (IOC) variant is scarce in cross-sectional imaging. Anatomical variations in the sphenoid sinuses, including optic, maxillary, and vidian nerves, raise interest among specialists involved in advanced sinonasal procedures. The infraorbital nerve's (ION) course along the orbital floor and its abnormal positioning within the orbital and maxillary sinus region pose risks of iatrogenic complications. A comprehensive radiological assessment is crucial before sinonasal surgeries. Cone-beam computed tomography (CBCT) is preferred for its spatial resolution and reduced radiation exposure. OBJECTIVE: The aim of this study was to describe the prevalence of anatomical variants of the infraorbital canal (IOC) and report its association with clinical condition or surgical implication. METHODS: We searched Medline, Scopus, Web of Science, Google Scholar, CINAHL, and LILACS databases from their inception up to June 2023. Two authors independently performed the search, study selection, data extraction, and assessed the methodological quality with assurance tool for anatomical studies (AQUA). Finally, the pooled prevalence was estimated using a random effects model. RESULTS: Preliminary results show that three types are prevalent, type 1: the IOC does not bulge into the maxillary sinus (MS); therefore, the infraorbital foramen through the anterior wall of MS could be used for identification of the ION. Type 2: the IOC divided the orbital floor into medial and lateral aspects. Type 3: the IOC hangs in the MS and the entire orbital floor lying above the IOC. From which the clinical implications where mainly surgical, in type 1 the infraorbital foramen through the anterior wall of MS could be used for identification of the ION, while in type 2, since the lateral orbital floor could not be directly accessed an inferiorly transposition of ION is helpful to expose the lateral orbital wall directly with a 0 scope; or using angled endoscopes and instruments, however, the authors opinion is that direct exposure potentially facilitates the visualization and management in complex situations such as residual or recurrent mass, foreign body, and fracture located at the lateral aspect of the canal. Lastly, in type 3, the ION it's easily exposed with a 0° scope. CONCLUSIONS: This systematic review identified four IOC variants: Type 1, within or below the MS roof; Type 2, partially protruding into the sinus; Type 3, fully protruding into the sinus or suspended from the roof; and Type 4, in the orbital floor. Clinical recommendations aim to prevent nerve injuries and enhance preoperative assessments. However, the lack of consistent statistical methods limits robust associations between IOC variants and clinical outcomes. Data heterogeneity and the absence of standardized reporting impede meta-analysis. Future research should prioritize detailed reporting, objective measurements, and statistical approaches for a comprehensive understanding of IOC variants and their clinical implications. Open Science Framework (OSF): https://doi.org/10.17605/OSF.IO/UGYFZ .

Minimally Anterior Medial Maxillary Approach (MAMMA): a novel technique for a wide access to the maxillary sinus.

PURPOSE: To describe a novel endoscopic technique to approach the maxillary sinus (MS), the Modified Anterior Medial Maxillary Approach (MAMMA), preserving the inferior turbinate (IT) and the nasolacrimal duct (NLD). To perform radiological measurements and describe a case series to study the feasibility and limits of MAMMA. METHODS: Computed tomography (CT) scans (n = 150 nasal cavities) were used to calculate areas of the MAMMA to define surgical limits and extensions. Measurement of distances to critical anatomy landmarks and total area for the MAMMA were calculated. An instructional case illustrating the surgical technique and outcome was also included. RESULTS: Radiological analysis showed a mean distance from the Piriform Aperture (PA) to the anterior limit of the NLD of 1.03 ± 0.18 cm (range 0.59-1.48) and a mean distance from de PA to the posterior limit of the NLD of 1.57 ± 0.22 cm (range 1.02-2.11). The mean distance from the nasal floor to the Hasner's valve was 1.61 ± 0.27 cm (range 1.06-2.52) and the distance from the nasal floor to the insertion of the IT was 2.20 ± 0.36 cm (range 1.70-3.69). Finally, the mean total area for the MAMMA was 4.04 ± 0.52 cm2 (range 3.17-5.53). No complications or recurrence of the pathology were observed in operated patients. CONCLUSION: The MAMMA provides a wide surgical field of the MS walls comparable to more aggressive techniques, with preservation of the sinonasal and lacrimal function. MAMMA is an effective alternative to treat different MS pathologies including benign recurrent maxillary sinus tumors.

Growth and microanatomy of the paranasal sinuses in two species of New World monkeys.

Paranasal sinuses of living apes and humans grow with positive allometry, suggesting a novel mechanism for bone enlargement. Here, we examine the paranasal sinuses of the owl monkey (Aotus spp.) and a tamarin (Saguinus midas) across postnatal development. The prediction that paranasal sinuses grow disproportionately faster than the main nasal chamber is tested. We used diffusible iodine-based contrast-enhanced computed tomography and histology to study sinuses in eight Aotus and three tamarins ranging from newborn to adult ages. Sinuses were segmented at the mucosa-air cavity interface and measured in volume. All sinuses were lined by a ciliated respiratory epithelium, except for the ethmoid air cells in Aotus, which are lined in part by olfactory epithelium. An age comparison indicates that only the maxillary sinus and ethmoid air cells are present in newborns, and two additional sinuses (invading the orbitosphenoid and the frontal bone), do not appear until late infancy or later. Comparing newborns and adults, the main nasal airway is 10 times larger in the adult Aotus and ~ 6.5 times larger in adult Saguinus. In contrast, the maxillary sinus far exceeds this magnitude of difference: 24 times larger in the adult Aotus and 46 times larger in adult Saguinus. The frontal sinuses add significantly to total paranasal space volume in both species, but this growth is likely delayed until juvenile age. Results suggest ethmoid air cells expand the least. These results support our prediction that most paranasal sinuses have a distinctly higher growth rate compared to the main nasal chamber.

Cone-beam computed tomographic analysis of maxillary sinus septa among Yemeni population: a cross-sectional study.

BACKGROUND: Maxillary sinus septa increase perforation risk of Schneiderian membrane during the sinus floor elevation (SFE). Cone Beam Computed Tomography (CBCT) allows for a more precise assessment of the septal position; thus, preoperative CBCT analysis is substantial to avoid possible complications. This study aims to investigate the 3D characteristics of the maxillary sinus septa based on CBCT images. To our knowledge, no study reported the CBCT-based investigation for the sinus septa among Yemeni population. MATERIALS AND METHODS: This is a retrospective cross-sectional analysis of 880 sinus CBCT images 440 patients. The septa prevalence, locations, orientations, morphology, and associated factors were analyzed. The effect of age, gender, and dental status on the sinus septa and the relationship between sinus membrane pathology and sinus septa were also analyzed. Anatomage (Invivo version 6) was used for CBCT images analysis. Descriptive and analytical statistics were performed, and a P-value < 0.05 was significantly considered. RESULTS: The maxillary sinus septa were found among 63.9% of patients and 47% of sinuses. The average septa height was 5.2 mm. 15.7% of patients had septa in the right maxilla, 18% in the left, and 30.2% in both. Gender, age, and dental condition had no influence on the presence of septa, and septa presence did not influence sinus membrane pathology. Many septa originated from the floor (54.5%), located in the middle (43%), with coronal orientation (66%) and complete configuration (58.2%). CONCLUSION: Based on our findings, the septa prevalence, locations, orientations, and morphology were significant and equivalent to the highest recorded in the literature yet. Thus, when sinus floor elevation is planned, CBCT imaging of the maxillary sinus is recommended for safe dental implantation.

Assessment of the prelacrimal recess in different maxillary sinus pneumatizations in relation to endoscopic prelacrimal recess approaches: a computed tomography study.

PURPOSE: To assist in planning before the endoscopic prelacrimal recess (PLR) approach, we aimed to investigate the relationship between morphometry and variations of PLR in maxillary sinus (MS) pneumatizations. METHODS: Retrospective analysis of the paranasal sinus computed tomography images of 150 patients was conducted to determine the pneumatization patterns of the MS, PLR variations, and the applicability of the PLR approach. The results were compared based on lateralization, gender, and age groups. RESULTS: The PLRwidth, the anteroposterior diameter of the nasolacrimal duct (NLD), the vertical and horizontal diameters of the MS were the highest in hyperplasic MS, and decreased significantly with increasing age (p = 0.005, p = 0.017, p = 0.000), respectively. Most of the morphometric measurements were higher in hyperplasic MS, while the medial wall thickness of PLR was higher in hypoplasic MS. The PLRwidth for feasibility of the PLR approach were Type I (48%) in hypoplasic MS and Type III (80%) in hyperplasic MS (p < 0.001), respectively. The PLR medial wall thickness was higher in Type I, while the piriform aperture angle (PAA), MS volume, length, and slope of the NLD were higher in Type III PLRwidth (p = 0.000), respectively. The highest anterior and separation-type variations of the PLR were observed in hyperplasic MS, whereas 31.0% of hypoplasic MS had no PLR (p < 0.001). CONCLUSION: This study revealed that PLRwidth and PAA were the highest in hyperplasic MS, which allows the endoscopic PLR approach to be performed more easily. For safer and uncomplicated surgery, surgeon should be aware of the PLR anatomy in different MS pneumatization patterns.

Relación entre el seno maxilar y ápices de dientes postero- superiores con tomografía computarizada de haz cónico / Relationship between the maxillary sinus and apices of posterior-superior teeth using cone beam computed tomography

El conocimiento de la relación entre el seno maxilar y los ápices de los dientes posterosuperiores es fundamental para evitar complicaciones frente a distintos tratamientos. Estudio descriptivo de corte transversal, con muestra por conveniencia de 383 imágenes de raíces de dientes posterosuperiores obtenidas por medio de tomografía computarizada de haz cónico (TCHC) de un centro radiológico en Viña del Mar, Chile. Cada raíz fue clasificada según su relación vertical con el seno en 4 categorías (0: ápice no se encuentra en contacto con contorno inferior del seno; 1: ápice en contacto con seno; 2: ápice lateralmente al seno; 3: ápice se protruye en seno). Además se midió su distancia en mm. Los datos fueron analizados con estadística descriptivas. El diente más lejano al seno maxilar fue el primer premolar superior (4.2 mm), seguido por el segundo premolar superior (1 mm). En el primer molar superior la raíz más lejana fue la mesio-vestibular (MV) 1mm, seguida por la raíz disto-vestibular (DV) 0.6mm y la raíz palatina (P) -1mm. En el segundo molar superior la raíz más lejana fue P 0.4mm, luego la DV 0.3mm, y MV -0,11mm. En cuanto a las categorías, se observó que la mayoría de las raíces se encuentran alejadas del seno siendo la raíz P del primer molar superior y la raíz MV del segundo molar superior las que se encuentran mayormente protruidas (42 % y 26 % respectivamente). El primer premolar es el diente posterosuperior que se encuentra más alejado del seno maxilar y a medida que se avanza hacia posterior hay tendencia a disminuir la distancia entre los ápices y el seno maxilar.

SUMMARY: Knowledge of the relationship between the maxillary sinus and the apices of the upper posterior teeth is crucial to avoid complications when considering different treatments. A descriptive cross-sectional study was carried out, with a convenience sample of 383 images of upper posterior teeth roots, obtained by means of cone beam computed tomography (CBCT) from a radiological center in Viña del Mar, Chile. Each root was classified according to its vertical relationship with the sinus into 4 categories (0: apex is not in contact with the lower contour of the sinus; 1: apex is in contact with the sinus; 2: apex laterally to the sinus; 3: apex protrudes in sinus). In addition, its distance was measured in mm. The data were analyzed with descriptive statistics. The tooth farthest from the maxillary sinus was the maxillary first premolar (4.2 mm), followed by the maxillary second premolar (1 mm). In the upper first molar, the most distant root was the mesiobuccal (MV) 1mm, followed by the distobuccal root (DV) 0.6mm and the palatal root (P) -1mm. In the upper second molar, the furthest root was P 0.4mm, then DV 0.3mm, and MV -0.11mm. In reference to the categories, it was observed that most of the roots are far from the sinus, with the P root of the first upper molar and the MV root of the second upper molar being the most protruding (42 % and 26 % respectively). The first premolar is the posterior maxillary tooth that is furthest from the maxillary sinus and as one advances posteriorly there is a tendency to decrease the distance between the apices and the maxillary sinus.

Análisis bidimensional de la permeabilidad de vías aéreas con el tamaño de senos maxilares y su relación con el desarrollo de la clase esqueletal en una población mexicana / Two-dimensional analysis of airway permeability with maxillary sinus size and its relationship with the development of skeletal class in a Mexican population

Comparar la permeabilidad de las vías aéreas y el tamaño de los senos maxilares en relación con la clase esqueletal. se midieron 90 radiografías lateral de cráneo, divididas en 3 grupos, comparando las 3 clases esqueletales, las cuales se determinaron con la medida ANB de Steiner, y estas a su vez en dos subgrupos que fueron hombres y mujeres, en las cuales se utilizó el análisis de McNamara para el análisis de vías aéreas y para el área del seno maxilar se tomaron dos medidas una antero-posterior y cefálica-caudal. Al comparar los hombres con las mujeres se identificó significancia estadística en vía área superior de clase II (p=≤0.017), vía aérea inferior de clase III (p=≤0.006). Al comparar las clases esqueletales en hombres se identificó diferencias en la vía aérea superior en las clases I vs III (p=≤0.05), inferior en la clase I vs III (p=≤0,001) y II vs III (p=≤0.044). Con respecto a mujeres se identificó significancia en la vía aérea superior al comparar la clase I vs II (p=≤0,043), vía aérea inferior en la clase II vs III (p=≤0.05), longitud del seno maxilar al comparar clase I vs II (p=≤0.017). Entre la clase I esqueletal y la clase II, el tamaño de los senos maxilares resulto menor en longitud en las mujeres de clase II esqueletal. Entre la clase I y clase III esqueletal en hombres, se encontró una longitud menor en la vía aérea superior e inferior en la clase I. Las vías aéreas resultaron en menor tamaño en sujetos de clase II.

SUMMARY: To compare the airway permeability and the size of the maxillary sinuses in relation to the skeletal class. 90 lateral skull radiographs were divided into 3 groups, comparing the 3 skeletal classes, which were determined with Steiner's ANB measurement, and these were once in two subgroups that were men and women, in any McNamara analysis was used for the analysis of airways and for the maxillary sinus area measurements were made an antero-posterior and cephalic-caudal. When comparing males with females, statistical significance was identified in the upper class II route (p=≤0,017), lower class III airway (p=≤0.006). At least skeletal classes in men, differences were identified in the upper airway in classes I vs III (p=≤0.05), lower in class I vs III (p=≤0.001) and II vs III (p=≤0.044). With respect to women, significance was identified in the upper airway when comparing class I vs II (p=≤0.043), lower airway in class II vs. III (p=≤0.05), maxillary sinus length to class I vs II (p=≤0.017). Between skeletal class I and class II, maxillary sinus size was shorter in length in skeletal class II women. Between class I and skeletal class III in men, a lower length was found in the upper and lower airways in class I. The airways were found to be smaller in class II subjects.

Incidence of maxillary sinus septa in the saudi population.

BACKGROUND: The variability in the maxillary sinus anatomy makes dental implant planning challenging. One of the anatomical landmarks that could affect the decision for implant placement around the maxillary sinus is the sinus septa. This study aimed to retrospectively determine the prevalence, anatomical distribution, and morphology of the maxillary sinus septa. MATERIALS AND METHODS: This study included 309 CBCT images that were analyzed to determine the prevalence, height, location, and orientation of the maxillary sinus septa. Descriptive statistics, Mann‒Whitney U tests, and Kruskal‒Wallis tests were used for data analysis. RESULTS: A total of 618 maxillary sinuses were analyzed. Maxillary septa were present in 30% (n = 188) of the sinuses and in approximately 45% of the analyzed images. The mean height of the septa was 5.09 mm. The presence of bilateral septa was evident in 49 subjects (35.25%). Female subjects were significantly more likely to have only one septum (n = 67, 53.6%, p < 0.05). CONCLUSION: The presence of septa is very common, found in one-third to approximately half of the evaluated cases, which warrants careful examination before any surgical interventions to avoid possible complications.

Are maxillary sinus variations related to maxillary sinus diameters?

OBJECTIVES: The reasons why the maxillary posterior region is challenging for dentists are its structure and anatomical variations. For this reason, it is necessary to have complete knowledge about the anatomy of this region. In dentistry, necessary information for the desired evaluation in this region can be provided by CBCT. The fact that it provides a three-dimensional evaluation and has measurement reliability emphasizes its importance in surgical applications. The septa, haller cell, and accessory ostium are variations of the maxillary sinus. There are few studies in the literature examining the relationship between maxillary sinus diameters and its variations. The aims of this study are to determine the prevalence of maxillary sinus variations and the average of maxillary sinus diameters, to examine their relationships according to age and gender, and to evaluate the effects of maxillary sinus diameters on variations. METHODS: In this retrospective study, CBCT images of 212 patients were examined. The examined CBCT images were analysed and recorded in more than one section. Descriptive statistics, chi-square tests, independent t test, one-way Anova tests were used to evaluate the data. RESULTS: As a result, a statistically significant difference was observed between the variations, gender and age groups in terms of morphometric characteristics of the maxillary sinus. The most common variation was observed to be accessory ostium. CONCLUSIONS: The rate of patients with at least one anatomical variation was 77.8%. For this reason, a detailed analysis should be performed to avoid complications before surgical procedures are performed in the area.

Does the floor of the maxillary sinus affect tooth movement for premolar extraction space closure?

OBJECTIVE: The study investigated orthodontic tooth movement by comparing various horizontal and angular measures of the teeth having different sinus-root relationship (SRR) of patients undergoing first premolar extraction treatment protocols. MATERIALS AND METHODS: This retrospective cross-sectional study included 45 Taiwanese adult patients, classified as the control group (n = 15) and the sinus group (n = 30) according to SRR. The control group had type I SRR (sinus floor above the level connecting the buccal and palatal root apices), whereas the sinus group included patients with type V SRR (the buccal and palatal root displayed apical protrusion into the sinus floor). Morphology was identified using pretreatment orthopantomograms. Lateral cephalometric measurements were conducted before treatment (T1) and at debonding (T2). RESULTS: Post debonding, there were no statistically significant difference in the two groups. However, the incisors in the control group became marginally more upright than those of the sinus group, and the molars demonstrated tipping movement with minimal anchorage loss in the sinus group than in the control group. The total treatment time was not significantly different between the 2 groups. CONCLUSION: The study revealed that the sinus-root relationship does not affect the orthodontic tooth movement. However, a more extensive 3-D study with larger sample size is strongly recommended before coming to any conclusion. CLINICAL RELEVANCE: The lining of the floor of the maxillary sinus does not affect the orthodontic tooth movement.

The Use of 0° and 70° Endoscopes in Maxillary Antrostomy.

BACKGROUND AND OBJECTIVES: Performing an effective maxillary antrostomy is critical to improving chronic maxillary sinusitis symptomatology. Incomplete dissection of the uncinate process and failure to incorporate the natural drainage pathway may lead to recirculation and need for revision surgery. The purpose of this study is to determine if 70° endoscopes provide added value in determining incomplete dissection or residual disease. METHODS: Prospective study of 35 sinuses from 18 patients undergoing FESS for Chronic Rhinosinusitis (CRS) between 11/1/2020 and 4/30/2021. Two fellowship trained Rhinologists initially performed maxillary antrostomies exclusively using a 0° endoscope, then transitioned to a 70° endoscope. Surgeons completed a survey to assess completion of the antrostomy prior to use of 70° endoscope, sino-nasal anatomy, and difficulty of the operation. Intraoperative photographs before and after using a 70° endoscope were evaluated by a third party. Pre-operative CT scans were used to evaluate the sphenoid keel-caudal septum-nasolacrimal duct (SK-CS-NL) angle. RESULTS: Of 35 sinuses from 18 patients all 35 sinuses had CRS with 48.5% having nasal polyposis and 42.9% having active infection. There was residual inflammatory tissue in the anterior maxillary sinus, including polypoid tissue and uncinate process prior to using the 70° endoscope in 82.9% of sinuses. The natural drainage pathway was not incorporated into the dissection in 28.6% of sinuses before converting to 70° endoscope. Incomplete dissection with 0° endoscope was not associated with nasal polyposis (P = .086) or uncinate position (0.741). Narrow SK-CS-NL angles were associated with incomplete dissection of the anterior maxillary sinus with 0° endoscope (16.0° ± 3.0° vs 20.6° ± 3.2°; P = .013). CONCLUSION: Use of 70° endoscope in maxillary antrostomy may be beneficial in identifying and resecting disease within the anterior maxillary sinus that may otherwise be difficult to find using a 0° endoscope. This is especially true in patients with narrow nasolacrimal duct positioning.

Anatomical localization of posterior superior alveolar artery: A retrospective study by cone-beam computed tomography.

BACKGROUND: Familiarity with the anatomy of the arteries in the sinus wall is essential to prevent the perforation of the sinus membrane and bleeding during dental implant surgery. OBJECTIVES: The aim of the study was to evaluate the anatomical position of the posterior superior alveolar artery (PSAA), using cone-beam computed tomography (CBCT). MATERIAL AND METHODS: A total of 245 CBCT scans met the eligibility criteria for this cross-sectional study. The vertical distance from the lower border of the artery to the lower border of the sinus floor, the diameter of the artery, and the type of artery (intrasinusoidal, intraosseous or superficial) in the first and second premolar and molar regions were measured. The data was analyzed with the t tests, the one-way analysis of variance (ANOVA) and the χ2 tests. RESULTS: The maxillary PSAA was recognized in 187 (76.3%) scans. The mean distance between the artery and the floor of the sinus was 6.87 ±3.68 mm. The mean diameter of the artery was 1.37 ±0.61 mm. The greatest mean diameter of the artery was observed in the second premolar region, and the smallest in the first molar region. As many as 63.6% of the arteries were intraosseous, 28.9% intrasinusoidal, and 7.5% superficial. CONCLUSIONS: Due to the high prevalence of the intraosseous type, in most cases of sinus lift surgery there is an increased possibility of PSAA damage. As the largest diameter of the artery was observed in the second premolar region, the possibility of severe bleeding during sinus lift surgery in this area is increased. The average distance between the artery and the floor of the sinus was approx. 7 mm. Consequently, it is recommended that the lower border of the sinus access window should be as high as 7 mm to the floor of the sinus.

Analysis of the Prevalence, Location, and Morphology of Maxillary Sinus Septa in a Northern Chinese Population by Cone Beam Computed Tomography.

Purpose: The purpose of this study is to survey the prevalence and morphology of the maxillary sinus septum, which might increase the rate of maxillary sinus membrane perforation during maxillary sinus floor elevation surgery, among northern Chinese, and to further analyze the relationship between gender, age, edentulous type, and prevalence of maxillary sinus septa. Methods: The cross-sectional retrospective study was based on an analysis of Cone Beam Computed Tomography (CBCT) images of maxillary sinus which had been obtained from patients who visited radiology department of Beijing Stomatology Hospital of Capital Medical University (Beijing, China) during the period from January 2019 to December 2019. The data of demographic characteristic, prevalence, position, direction, and morphology of maxillary sinus septum were collected and further analyzed by SPSS version 25.0.1 and R version 3.5.1 software program. Results: 595 patients were included in this study, and 1190 maxillary sinuses were analyzed and the incidence rate of the sinus septum was 46.9%. 399 (33.5%) sinuses had one or more septa in 279 (46.9%) patients. In addition, maxillary sinus septa incidence showed no significant differences among gender, age, and edentulous type. The segment second molar had the highest incidence rate of septa. Conclusion: In this study, a higher incidence of the maxillary sinus septum was found in the northern Chinese, and its distribution varied with its position, morphology, and direction.

The pterygopalatine ganglion, palatine nerves and vessels: dissection and pathway / El ganglio pterigopalatino, nervios palatinos y vasos: disección y trayecto

SUMMARY: Background and Objectives: The palatine nerves and vessels cross the pterygopalatine fossa, the palatine canals, the palatine foramina and the submucosal space, at the level of the hard palate and the palatine recess of the maxillary sinus. Their trajectory is long, complicated and difficult to highlight on a single dissection piece. In the literature that we studied, we did not find clear images that fully highlight the real configuration of the pterygopalatine ganglion and nerves and of the palatine vessels. Our aim was to provide a clear and representative dissection of the pterygopalatine ganglion and of the palatine neurovascular bundle throughout its pathway in a simple, coherent and useful presentation for the practitioners interested in the regional pathology. We resected the posterior and inferomedial osseous walls of the maxillary sinus and highlighted the neurovascular structures in the pterygopalatine fossa and the wall of the maxillary sinus. We photographed the dissection fields and detailed the important relations. The images that we obtained are clear, simple and easy to interpret and use. We successfully highlighted the aspect and the main relations of the pterygopalatine ganglion and the pathway and distribution of the palatine nerves and vessels, from their origin to the terminal plexuses. There is a broad spectrum of clinical procedures or situations that require a proper knowledge and understanding of the anatomical pathway and relations of the palatine neurovascular elements. This includes the various types of regional anesthesia, tumor resection surgery, flaps of the palatine mucosa, the LeFort osteotomy etc. Demonstration of the pterygopalatine ganglion and its relations is useful in endoscopic interventions at the level of the pterygopalatine fossa.

RESUMEN: Los nervios y vasos palatinos atraviesan la fosa pterigopalatina, además de los canales palatinos, los forámenes palatinos y el espacio submucoso a nivel del paladar duro y el receso palatino del seno maxilar. Su trayectoria es larga, complicada y difícil de destacar en una sola pieza de disección. En la literatura que estudiamos, no encontramos imágenes claras que resalten completamente la configuración real del ganglio y los nervios pterigopalatinos y de los vasos palatinos. Nuestro objetivo fue proporcionar una disección clara y representativa del ganglio pterigopalatino y del haz neurovascular palatino a lo largo de su trayecto en una presentación simple, coherente y útil para los médicos interesados en la patología regional. Resecamos las paredes óseas posterior e inferomedial del seno maxilar y resaltamos las estructuras neurovasculares en la fosa pterigopalatina y la pared del seno maxilar. Fotografiamos los campos de disección y detallamos las relaciones importantes. Las imágenes que obtuvimos son claras, sencillas y de fácil interpretación. Resaltamos con éxito el aspecto y las principales relaciones del ganglio pterigopalatino y el trayecto y distribución de los nervios y vasos palatinos, desde su origen hasta los plexos terminales. En conclusion, existe un amplio espectro de procedimientos o situaciones clínicas que requieren un adecuado conocimiento y comprensión del trayecto anatómico y las relaciones de los elementos neurovasculares palatinos. Esto incluye los distintos tipos de anestesia regional, cirugía de resección tumoral, colgajos de mucosa palatina, osteotomía de LeFort, etc. La demostración del ganglio pterigopalatino y sus relaciones es útil en intervenciones endoscópicas a nivel de la fosa pterigopalatina.

Anatomical Changes in a Case with Asymmetrical Bilateral Maxillary Sinus Hypoplasia.

Background and Objectives: The maxillary sinus hypoplasia (MSH) is an occasional variation of the maxilla, occurring either unilaterally or bilaterally. Previous studies dealing with MSH have not detailed the consequent anatomical changes of the maxilla and adjacent fossae. Materials and Methods: A 58-year-old female case was scanned in Cone Beam Computed Tomography and found to have asymmetrical bilateral MSH, who was then further evaluated anatomically. Results: The maxillary sinuses were hypoplastic and had mild mucosal thickenings. The orbital floors were curved. The uncinate process and the ethmoidal infundibulum were laterally displaced beneath the orbit floor. On each side, the lateral nasal wall protruded within the respective maxillary bone to reach above the vestibular cortical plate of the alveolar process. This expansion of the lateral nasal walls was limited to the premolar and first molar regions. The inferior turbinates were laterally curved. The perpendicular palatine plate was building a postero-lateral nasal wall in front of the pterygopalatine fossa. Conclusions: The classification systems of MSH should be detailed to indicate whether the normal uncinate process is medial or inferior to the orbit. The lateral expansion of the lateral nasal wall in MSH is limited to the anterior part of that wall. The laterally expanded nasal fossa could reach anterior to the pterygopalatine fossa in MSH. Seemingly, CBCT is a better tool than CT to evaluate the detailed anatomy of the modified anatomical structures in MSH; as such, it could be of help in a surgical approach.

Comparison of biological and mechanical properties of different paranasal sinus mucosa in goat.

OBJECTIVE: The present study was designed to explore endurable pressure intensity of different paranasal sinus mucosa in goats. METHOD: Mucosa commonly involved in maxillary sinus augmentation, including mucosa from maxillary sinus crest, maxillary sinus floor, and frontal sinus, were harvested in a computed tomography-guided manner. The obtained mucosa was then sectioned into square and irregular ones for maximum endurable pressure intensity determination and morphological observation, respectively. RESULTS: Thickness of paranasal sinus mucosa, as determined under morphological staining by an optical microscope with a graduated eyepiece, were calculated. And the results showed that the average thickness of maxillary sinus crest mucosa, floor mucosa, and frontal sinus mucosa in goats were 410.03 ± 65.97 µm, 461.33 ± 91.37 µm and 216.90 ± 46.47 µm, respectively. Significant differences between maxillary sinus crest and frontal sinus, maxillary sinus floor, and frontal sinus were observed (P < 0.05). Maximum endurable pressure intensity was determined by utilizing a self-made clamp device and the results revealed maximum endurable pressure intensity of maxillary sinus crest mucosa, floor mucosa and frontal sinus mucosa in goats were 260.08 ± 80.12Kpa, 306.90 ± 94.37Kpa and 121.72 ± 31.72Kpa, respectively. Also, a statistically significant difference was observed when comparing the endurable pressure intensity between maxillary sinus crest and frontal sinus, maxillary sinus floor, and frontal sinus (P < 0.05). Further correlation analysis also revealed a positive correlation between the thickness of mucosa of the maxillary sinus and frontal sinus and maximum endurable pressure intensity (P < 0.05). CONCLUSION: Mucosal thickness and maximum endurable pressure intensity of maxillary sinus crest and floor were larger than that of frontal sinus mucosa and a positive correlation between the thickness of mucosa and endurable pressure intensity was observed. Our results thus might provide an experimental basis and guidance for mucosa-related problems involved maxillary sinus augmentation.