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

Collaboration between otolaryngologists and oral surgeons in maxillary sinus elevation planning

BACKGROUND

The collaboration between otolaryngologists and dental providers is crucial for the planning and execution of maxillary sinus elevation (MSE) procedures, which are integral to successful dental implant placements.

PURPOSE

This article examines the essential role of otolaryngological assessments in identifying potential sinonasal risks that could impact the outcomes of MSE.

MATERIALS AND METHODS

A comprehensive narrative review of existing literature was conducted.

DISCUSSION

The review underscores the importance of thorough preoperative evaluations, including patient history, computed tomography (CT) or cone-beam CT (CBCT) scans, and nasal endoscopy, to mitigate sinonasal health risks. It details various clinical scenarios and patient assessments, emphasizing a systematic approach to diagnosing and managing sinonasal conditions proactively. The discussion reveals that while some sinus conditions may not significantly affect MSE success, conditions impacting mucociliary clearance and sinus drainage are critical risk factors requiring otolaryngological intervention. Additionally, the article introduces a grading system to assist clinicians in identifying patients who would benefit from otolaryngological evaluations prior to MSE.

CONCLUSION

This review highlights the value of interdisciplinary collaboration and standardized protocols in enhancing the predictability and safety of MSE procedures, ultimately improving patient outcomes.

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.

Anatomy of Maxillary Sinus: Focus on Vascularization and Underwood Septa via 3D Imaging

The study of the maxillary sinus anatomy should consider the presence of two features of clinical importance. The arterial supply course and the presence of the so-called Underwood septa are two important factors to consider when planning surgical treatment to reduce the risk of surgical complications such as excessive bleeding and Schneiderian membrane perforations. This study aimed to investigate the above-mentioned anatomical structures to improve the management of eventual vascular and surgical complications in this area. This study included a total of 200 cone-beam computed topographies (CBCTs) divided into two groups of 100 CBCTs to evaluate the arterial supply (AAa) course through the lateral sinus wall and Underwood's septa, respectively. The main parameters considered on 3D imaging were the presence of the AAa in the antral wall, the length of the arterial pathway, the height of the maxillary bone crest, the branch sizes of the artery in the first group, and the position of the septa, the length of the septa, and their gender associations in the second group. The CBCT analysis showed the presence of the arterial supply through the bone wall in 100% of the examined patients, with an average size of 1.07 mm. With regard to the septa, 19% of patients presented variations, and no gender difference was found to be statistically significant. The findings add to the current understanding of the clinical structure of the maxillary sinus, equipping medical professionals with vital details for surgical preparation and prevention of possible complications.

Anatomic evaluation of the posterior superior alveolar artery using cone-beam computed tomography: A systematic review and meta-analysis

Purpose

This systematic review examined the detection of the posterior superior alveolar artery, along with various anatomic characteristics, on cone-beam computed tomography images.

Materials and Methods

Studies were identified electronically through the Web of Science, MEDLINE, Scopus, and Embase databases. The quality of the included studies was evaluated using a 5-item binary scale. The detection rate, location, and classified diameter of the posterior superior alveolar artery were estimated as prevalence values. The diameter of this artery, as well as the distances from the artery to the alveolar crest and sinus floor, were estimated as means with associated 95% confidence intervals.

Results

Thirty-seven studies were enrolled, with 34 of these included in the meta-analysis. The mean detection rate was 79% (range: 72%-84%), and the mean diameter was 1.06±0.05 mm (range: 0.96-1.16 mm). The posterior superior alveolar artery was located intraosseously in 64% of cases. The mean distance of the artery from the alveolar crest was 16.71±0.49 mm (range: 15.75-17.68 mm), while the mean distance from the artery to the sinus floor was 8.85±0.4 mm (range: 8.05-9.64 mm).

Conclusion

According to the findings of this meta-analysis regarding various anatomic characteristics of the posterior superior alveolar artery, severe hemorrhage after damage to this artery during sinus augmentation procedures is not a substantial clinical problem.

Characteristics of maxillary sinus ostia and their correlation with anatomic variations of the osteomeatal complex: Indications for sinus floor elevation

Background

Knowledge of the anatomy and variations of the maxillary sinus is essential for reducing oral surgery complications, such as sinus floor elevation, and increasing surgery success. The CBCT images of 385 patients were examined.

Materials and Methods

The prevalence, localization, and height of PMO (Primer Maxillary Ostium) and AMO (Accessory Maxillary Ostium) were evaluated with respect to sex, dentition, dental treatment, Schneiderian membrane (SM) thickness, concha bullosa, Haller Cells, and septal deviation.

Results

The PMO was present in 87.3% of all patients. Further analysis showed that the mean PMO diameter was 1.42 ± 0.62 mm. Although 11.6% of the PMO was in the inferior region, 60.4% was in the middle and 28% in the superior region. The effect of age and SM on the height and diameter of the PMO was found to be statistically significant. An AMO was present in 20% of the CBCT images. The mean AMO diameter was 2.55 ± 1.25 mm. Although 45.4% of the AMO was in the inferior region, 48% was in the middle and 6.6% was in the superior region. Moreover, SM thickness seemed to influence the height. A significant positive relationship was found between the PMO and AMO height. Also, a significant relationship was observed between the presence of the AMO and septum deviation.

Conclusion

The presence of the AMO, PMO diameter, and height should be added to the preoperative evaluation criteria for the success of sinus floor evaluation. Specifically, sinonasal and demographic conditions should be carefully examined preoperatively for the long-term success of the surgery.

Frequency, location, and diameter of the anastomosis between the posterior superior alveolar artery and the infraorbital artery in imaging studies: systematic review and meta-analysis

The anastomosis between the posterior superior alveolar artery (PSAA) and the infraorbital artery (IOA) courses along half of the lateral wall of the maxillary sinus. Risk of injury to the anastomosis between PSAA and IOA during surgical procedures has been reported. The aim of the present study was to carry out a systematic review and meta-analysis to determine the frequency, location, and diameter of the anastomosis between PSAA and IOA in imaging studies (cone-beam computed tomography, spiral cone-beam computed tomography, and computed tomography). A search was carried out in the PubMed, EMBASE, and LILACS. Original works were included reporting imaging studies to analyze the frequency, location, and diameter of the anastomosis in humans. The risks of bias were analyzed using the AQUA tool. Generalized linear mixed models were used to estimate the frequency and the 95% CI in the meta-analysis. The variance in prevalence estimates was stabilized by logit transformation. The qualitative analysis included 49 studies with 10,837 patients. The frequency of the anastomosis between PSAA and IOA was 74% (prediction interval 0.20-0.97%). The anastomosis was most frequently located in the intraosseous region (60.0%), followed by the submembranous region (33.0%), and least frequently in an extraosseous location (5.0%). Arteries with diameter of 1.0-1.9 mm were most frequent (32.0%), followed by arteries with diameter less than 1 mm (23.0%); a small number with diameter greater than 2 mm was recorded (4.0%). These data can be used as a reference to help surgeons when planning interventions in the lateral wall of the maxillary sinus. Registration number: INPLASY, number 202120071.

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.

Anatomical variations and accessory structures in the maxilla in relation to implantological procedures: an observational retrospective study of 212 cases using cone-bean computed tomography

PURPOSE

This study used cone-beam computed tomography (CBCT) to analyze the prevalence of several maxillary anatomical/accessory structures, as well as variations within each type, assessing how accurate diagnosis can minimize the risk of intraoperative complications during implantological procedures in the oral cavity.

METHODS

212 CBCT scans of the maxilla were analyzed, captured over a period of 18 months for surgical planning purposes. The prevalence of posterior superior alveolar arteries (PSAA), maxillary sinus septa (MSS), and branches of the canalis sinuosus (CS) were evaluated, as were the diameter and location of each anatomical structure in horizontal and vertical planes. P < 0.05 was considered statistically significant.

RESULTS

PSAAs were observed in 99.1% of cases, the intrasinus type being the most frequent; MSS were noted in 15.6% of the sample, mainly in the posterior region with sagittal orientation; CS branches were observed in 50% of patients, mainly in relation to the incisors and significantly more prevalent among males.

CONCLUSIONS

The use of CBCT significantly increases the possibility of clearly identifying these anatomical structures. The differences found between patients highlight the importance of carrying out an exhaustive radiological study of the individual to prevent complications, such as Schneiderian membrane perforation, neurovascular damage or bleeding during surgery.

Application of an assembled surgical guide for lateral approach sinus augmentation and sinus septum management: A technical note

The presence of maxillary septa may render sinus augmentation more challenging particularly when encountered at the ideal implant position. This article demonstrated a novel technique for lateral access sinus augmentation using an assembled surgical guide to achieve proper lateral window outline, precise septum identification and osteotomy, and secure membrane detachment. This technique increases the predictability and efficiency of the procedure while reducing the risk of complications.

Anatomical Characteristics of the Accessory Maxillary Ostium in Three-Dimensional Analysis

Background and Objectives: The accessory maxillary ostium (AMO) can interfere with ventilation and drainage of the maxillary sinus, and therefore the importance of evaluating the anatomical features of the AMO has been emphasized. This study aimed to evaluate anatomical characteristics of the AMO together with the natural ostium (NO) using three-dimensional (3D) analysis and to assess the relationship between the AMO and maxillary sinus pathologies. Materials and Methods: This retrospective study included 394 sinuses in 197 patients. Using 3D computed tomography images, the prevalence of the AMO and concurrent sinus pathologies were examined. For patients with an AMO, 3D spatial positions of the AMO and NO related to adjacent anatomic structures and dimensions of the AMO and NO were evaluated. Results: A total of 84 sinuses showed single or multiple AMO, with a prevalence of 21.3%. The AMO was located superiorly by 30.1 mm from the maxillary sinus floor, inferiorly by 1.3 mm from the orbital floor, and posteriorly by 22.4 mm from the anterior sinus wall. The AMO was located 5.4 mm posteriorly and 0.7 mm inferiorly from the NO. On the same coronal plane as the NO or AMO, height from the maxillary sinus floor to the NO and AMO ranged from 19.4 to 45.8 mm and 14.5 mm to 41.9 mm, respectively. The mean horizontal and vertical dimensions were 5.9 mm and 4.6 mm for the NO and 2.8 mm and 3.0 mm for the AMO. We detected a significant association between the presence of the AMO and the mucosal thickening (p = 0.029). Conclusions: The results of this study suggest that, although the AMO and NO are mostly located in positions that do not limit sinus-related surgeries, such as maxillary sinus floor augmentation, the AMO and NO are also found in lower positions, which may be a detriment to the postoperative physiological function of the maxillary sinus and affect treatment outcomes.

Prevalence of canalis sinuosus and accessory canals of canalis sinuosus on cone beam computed tomography: a systematic review and meta-analysis

The aim of this systematic review was to determine the prevalence of the canalis sinuosus (CS) and accessory canals of the canalis sinuosus (ACCS) as identified on cone beam computed tomography (CBCT). Online searches were conducted in the MEDLINE (via PubMed), Scopus, LILACS, Cochrane CENTRAL, Web of Science, and SIGLE (via OpenGrey) databases. Primary studies that determined the prevalence of canalis sinuosus and/or its anatomical variations using CBCT were included. The risk of bias assessment was performed using the AQUA tool. The quality effects model using double arcsine transformation was used for the meta-analysis of prevalence. Heterogeneity, publication bias, and sensitivity analyses were performed. Of 3237 initial results, 17 papers were included for systematic review. The meta-analysis comprising 1994 patients showed a pooled prevalence of CS of 0.80 (95% confidence interval (CI) 0.51-0.99; P = 0.001; I² = 99%). Publication bias analysis revealed minor asymmetry (LFK index 1.84). The meta-analysis of 4605 patients showed a pooled prevalence of ACCS of 0.54 (95% CI 0.38-0.69; P = 0.001; I² = 99%). The sensitivity analysis showed a pooled prevalence of ACCS of 0.53 (95% CI 0.32-0.74; P = 0.001; I² = 99%) for studies with ≥ 1000 patients and 0.55 (95% CI 0.33-0.76; P = 0.001; I² = 98%) for studies with< 1000 patients. Canalis sinuosus showed a pooled prevalence of 0.80 and ACCS showed a pooled prevalence of 0.54; hence both should be considered as anatomical structures, which means that they are present in most people. Surgeons must be aware of the CS and ACCS on CBCT analysis during pre-surgical planning. PROSPERO REGISTRATION NUMBER: CRD42020154195.

Prevalence of and factors associated with maxillary sinus cyst in a Chinese population

PURPOSE

This study used cone-beam computed tomography (CBCT) to assess the prevalence of and factors associated with maxillary sinus cysts (MSCs) in a Chinese population.

METHODS

A total of 2,571 CBCT scans of 5,000 sinuses were analyzed. MSCs were diagnosed on the basis of imaging features within the maxillary sinus. Sex, age, dental condition, and anatomic condition were assessed. Associations with these factors were evaluated with logistic regression and a generalized estimating equations model.

RESULTS

The prevalence of MSCs was 15.46% at the sinus level and 23.44% at the patient level. The prevalence of MSCs was higher for men (OR = 1.864, P < 0.001) and for patients with apical lesions (OR = 1.76, P < 0.001), severe bone loss (OR = 1.363, P < 0.05), tooth roots in contact with the sinus floor (OR = 1.68, P < 0.001), and pits or septa on the floor of the maxillary sinus (OR = 1.539, P < 0.001).

CONCLUSION

This large sample had a high prevalence of MSCs. MSC prevalence was associated with multiple factors, including sex, dental condition, and anatomic condition. Maintenance of healthy dental and periodontal status might help prevent MSCs.

Prevalence of maxillary sinus septa: systematic review and meta-analysis

The aim of this systematic review and meta-analysis was to determine the prevalence and characteristics of maxillary sinus septa using cone beam computed tomography and computed tomography data. Publications were searched until October 5, 2020 in three electronic databases. Additionally, article bibliographies were searched, and authors were contacted if required. This review has been registered in PROSPERO (CRD42019124933). Two independent evaluators assessed methodological quality using the Joanna Briggs Institute levels of evidence; inter-rater reliability tests were performed (Cohen's κ). The prevalence of maxillary sinus septa was expressed as a proportion; differences according to sex were reported in terms of the odds ratio (OR) and 95% confidence interval (95% CI). Heterogeneity and sources of heterogeneity were evaluated by meta-regression. Publication bias was assessed by visual analysis of the funnel plot. Statistical significance was set at P < 0.05. The 62 studies identified and included in the review involved 13,701 patients (22,460 sinuses). The meta-analysis of 35 studies (14,664 sinuses) revealed an overall mean sinus septa prevalence per sinus of 33.2% (95% CI 27.8-38.5%; I² = 98.32%). The meta-analysis of 42 studies (9631 patients) found an overall mean sinus septa prevalence per patient of 41.0% (95% CI 36.0-46.0%, I² = 96.45%). The OR for the difference in septa prevalence between sexes was 0.785 (95% CI 0.590-1.046; P = 0.098, I² = 73.24%). Septa were most frequent in the middle area of the sinus and with a transverse orientation (86.0%). Within the limitations, the results suggest a high proportion of septa in the sinus, commonly in the middle area, which can interfere with the success of sinus floor elevation required for implant rehabilitation.

Fabricating a surgical template for guiding sinus floor elevation in the maxillary sinus septa with simultaneous implant placement: A dental technique

The presence of sinus septa, common anatomic structures of the maxillary sinus, may increase the incidence of surgical complications during sinus floor elevation. This article introduces a digital protocol for achieving safe and precise sinus floor elevation with an individualized surgical template that combines implant placement and the lateral sinus window technique. This technique facilitates precise preplanning and preparation of the lateral osteotomy window and the implant site and reduces surgical complications, shortens surgical duration, and improves patient-related outcomes.

A study on the association between accessory maxillary ostium and maxillary sinus mucosal thickening using cone beam computed tomography

BACKGROUND

Accessory maxillary ostium (AMO) has a major role to play in the aetiology of maxillary sinusitis. Mucosal thickening is one of the key radiographic features of chronic maxillary sinusitis. The aim of this study was to identify the location of the AMOs and investigate the association between Mucosal Thickening [MT] and AMO using Cone Beam Computed Tomography [CBCT].

METHODS

CBCT scans of 400 maxillary sinuses from the records of 200 patients who seeked various dental treatments at the Thumbay Dental Hospital, Gulf Medical University, Ajman, United Arab Emirates were evaluated. The incidence, anatomical position and maximal length of accessory maxillary ostia (AMO) in the maxillary antrum were reviewed using CBCT by two examiners. The association between MTs and AMOs were also analysed.

RESULTS

Among the 200 CBCT scans, 131 belonged to male patients and 69 scans belonged to female subjects within the age group of 18-65 years (mean age 41.32 years). AMOs were found in 142 maxillary antra (35.5 %). The inter-observer reliability for using CBCT to detect AMO was (k = 0.83). There was no significant difference in the frequency of AMOs when the age (P = 0.19) and gender (P = 0.54) distribution were considered. Sinuses with AMOs, showed significantly greater frequency of MTs (p = 0.001). AMOs with maximal length of less than 1mm were most commonly observed (51.40 %). AMOs with larger greater maximal length were associated with higher degrees of MT. The location of the AMOs, were not affected by the degree of MT.

CONCLUSIONS

The study demonstrates a clear association between degree of MT and occurrence of AMO in the maxillary sinus. However, the location of the AMO is independent of the degree of the MT. There is a greater probability of finding an AMO in the maxillary sinus if the MT in the sinus is more than 3 mm.

Evaluation of length and location of the maxillary sinus intraosseous artery using computerized tomography

BACKGROUND

The intraosseous artery is a branch of the posterior superior alveolar artery that supplies the lateral wall of the maxillary sinus. The present study seeks to analyze the location of the intraosseous artery and its site of termination.

METHODS

Cone beam computed tomography was used to evaluate 200 patients making up 400 maxillary sinuses. The following criteria were measured: (1) the distance of the lower border of the intraosseous artery to the floor of the sinus, (2) the average length of the artery, (3) the diameter of the artery, (4) the site at which the artery terminates at, and (5) the distance of the artery from the first premolar, second premolar, first molar, second molar, and third molar.

RESULTS

The intraosseous artery was identified in 336 (84.0%) quadrants. The most common site of termination was at the mesial of the second molar (22%), regardless of dental status and right or left quadrant. Its overall mean diameter was 0.91 ± 0.56 mm, with no difference within the dental status. Its overall mean length was 7.40 ± 3.39 mm, with a statistically significant difference between dentate and edentulous quadrants (P < 0.001). Its overall mean distance from the floor was 6.95 ± 6.49 mm, with no difference within the dental status. All parameters showed no difference between right or left quadrants.

CONCLUSIONS

The chances of encountering the intraosseous artery at the premolar area is <21% during a lateral window sinus floor elevation. The most common (22%) site of termination of the intraosseous artery is at the mesial of the second molar. Understanding of the course, location, and termination of the artery enhances the precision of a clinician when it comes to pre-operative treatment planning.

Axial Triangle of the Maxillary Sinus, and its Surgical Implication With the Position of Maxillary Sinus Septa During Sinus Floor Elevation: A CBCT Analysis

The aim of this study was to measure the convexity of the lateral wall of the maxillary (Mx) sinus and identify the locational distribution of antral septa in relation to the zygomaticomaxillary buttress (ZMB), in order to suggest another anatomical consideration and surgical modification of sinus floor elevation procedures. This study was designed as a cross-sectional study, and a total of 134 patients and 161 sinuses containing edentulous alveolar ridges were analyzed. The angle between the anterior and lateral walls of the Mx sinus (lateral sinus angle [LSA]), and the angle between the midpalatal line and the anterior sinus wall (anterior sinus angle [ASA]) were measured. Mean LSAs and ASAs were 105.9° ± 9.86° and 58.4° ± 6.43°, respectively. No significant difference between left and right sides was found (LSA, P = .420; right = 105.5° ± 9.27°; left = 105.5° ± 9.27° and ASA, P = .564; right = 57.9° ± 6.80°; left = 58.8° ± 6.02°). The prevalence of septa was 37.3%, and it was most frequently noted in the second molar region (32.8%), followed by the first molar (20.9%), retromolar (16.4%), and second premolar regions (14.9%). Septa were most frequently located posterior to the ZMB (49.2%), while ZMB was mostly located in the first molar region (66.4%). Narrow LSAs may complicate the surgical approach to the posterior maxilla, especially when sinus elevation should be used in the second molar region. Considering the occasional presence of antral septa, membrane elevation may be complicated when a septum is encountered during the procedure. These results suggest that 3-dimensional examination of the convexity of the Mx sinus should be performed preoperatively to choose proper surgical techniques and minimize surgical complications.

Anatomic variations of the osteomeatal complex and its relationship to patency of the maxillary ostium: A retrospective evaluation of cone-beam computed tomography and its implications for sinus augmentation

Aim:

The aim of this study is to determine the incidence of obliterated osteomeatal complex (OMC) due to the presence of anatomic variants.

Settings and Design:

Retrospective Study.

Materials and Methods:

In this retrospective study, a total of 71 patients, 34 males and 37 females, aged 35–65 years were included in the study. Cone beam computed tomography (CBCT) scans of patients were assessed to identify the status of the OMC in the presence of anatomic variants and their incidence was recorded. The radiological assessment of the anatomical variants was made by viewing the coronal sections of the scans. The variants observed were deviated nasal septum, uncinate process), agger nasi, Haller cells, middle turbinate variants, enlarged bulla, accessory ostium, and maxillary sinus abnormalities). Ostium patency was evaluated in the coronal section of each sinus and classified as “patent” or “obstructed.” The most common variants observed were then correlated with the patency of the ostium.

Statistical Analysis Used:

Chi square test was performed to assess the association between the anatomic variants and the patency of the OMC.

Results:

In the present study, the incidence of an obliterated OMC due to the presence of anatomic variants was 73.2%. The four most common variants associated with the possibility of an obliterated OMC were the deviated nasal septum (76.2%), middle turbinate (86.4%), enlarged bulla (77.8%), and sinus cavity variants (80.0%). A statistically significant association was noted between middle turbinate variants and Haller cells and the patency of the OMC.

Conclusion:

Thorough pretreatment CBCT evaluation should be performed to assess the presence of anatomic variants and thereby, the patency of the ostium before sinus floor elevation procedures. The pre and postsurgical treatment plans and regimes can be modified according to anticipated postsurgical sequelae, thereby avoiding postsurgical complications and enhancing the success of the graft procedure.

Evaluation of maxillary sinus anatomical variations and lesions: A retrospective analysis using cone beam computed tomography

INTRODUCTION

The residual bone height in the posterior edentulous maxilla is frequently limited by the maxillary sinuses. Sinus floor elevation (SFE) is then considered to restore sufficient bone height. The preoperative analysis of the maxillary sinus is necessary for the success of this surgery. Therefore, we investigated the frequency of maxillary sinus anatomic variations and lesions by using cone beam computed tomography (CBCT).

MATERIALS AND METHODS

We retrospectively analysed all CBCTs performed at a private radiological center between January and November 2014. The following anatomical variations and lesions were assessed: sinus ventilation, sinus septa, the sinus totally compartmentalized, the hypoplastic sinus, sinus aplasia, the prolapsed sinus, thickness of the anterolateral wall, the position of antral artery, mucosa thickening, sinus opacity, the polyps and the cysts.

RESULTS

A total of 300 cone beam images were analyzed. The findings consisted in: ventilation 91%, septa 34.66%, total compartmentalized sinus 6%, hypoplastic sinus 5%, aplastic sinus 0%, prolapsed sinus 1.66%, endorsed position of the antral artery 53%, submucosa position 43%, thickening of the sinus mucosa 41%, sinus opacity 4%, polyps and the cysts 20.33%. The average thickness of the anterolateral wall was about 1.16±0.48mm.

CONCLUSION

The maxillary sinus has great interindividual anatomical variability. The cone beam is highly beneficial for the analysis of the anatomical structures in relationships with any sinus surgery.

Anatomical analyses for maxillary sinus floor augmentation with a lateral approach: A cone beam computed tomography study

BACKGROUND

Various anatomical references and structures should be analyzed prior approaching a surgery in the maxillary sinus. The objective of the present study was to evaluate the anatomical structures and references involved in sinus floor elevation with a lateral approach.

MATERIALS AND METHODS

Seventy-five patients planned for sinus floor elevation were included in the study. Eighty-eight maxillary sinuses were evaluated using cone beam computed tomographies (CBCTs). The nasal floor was used as main reference (X) and sinus mucosa width, bone crest height, palatal-nasal recess angle (PNR), sinus width at the level of the nasal floor, distance from the nasal floor to the base of the sinus (X-F), position of the posterior superior alveolar artery (PSAA height) and diameter (PSAA diameter), lateral bone wall width at 3mm (LW 3mm) and 9mm (LW 9mm) from the base of the sinus (F), patency of the ostium (OP), and presence and position of septa have been evaluated.

RESULTS

The mean dimensions and standard deviations were the following: mucosa thickness was 2.0±1.4mm, bone crest height 2.8±1.4mm, distance X-F 8.3±1.9mm, PNR angle 135.5±23.1, sinus width 12.6±4.2mm, X-F 8.3±1.9mm, PSAA height 14.4±2.9mm, PSAA diameter 1.1±0.4mm, LW 3mm 1.5±1.2, LW 9mm 1.3±0.6mm, OP 1.9±0.4mm. Septa were present in 19.3% of the sinuses evaluated and were located mostly in the molar region.

CONCLUSIONS

In conclusion, the analysis of the CBCT before sinus floor elevation allows the identification of anatomical structures and references that might be used for the planning of the surgical approach, aiming to improve the outcome of the treatment and to avoid possible complications.

Analysis of maxillary sinus septa by cone-beam computed tomography

Abstract Introduction Pneumatization of the maxillary sinus may make it impossible to insert implants directly in the posterior region of the maxilla, and in these cases, the solution is to submit the patient to maxillary sinus floor augmentation surgery. The most common complication of this surgery is sinus membrane perforation. Anatomical variations of the internal space of the sinus, such as the bone septa, may further hamper detachment of this membrane. Objective To evaluate the prevalence and characteristics of sinus septa in patients from the Zona da Mata Mineira (Minas Gerais, Brazil), to offer relevant information for a safer planning of surgeries involving this region. Material and method A total of 120 patients (240 sinuses) were analyzed using cone-beam computed tomography (CBCT) images, verifying the presence of sinus septa and classifying them for size and anteroposterior location. Result Of the 120 patients analyzed, 45 (37.50%) had sinus septa, 66 septa in total. Of these, 33 (50%) were present in the middle region of the maxillary sinus and the mean septum size was 7.23 mm. There was no significant difference in the septum size between the genders or between the right and left sides. Conclusion The high rates of incidence of sinus septa justify their study, which should be based mainly on accurate exams, such as CBCT, since they represent one of the most relevant anatomical variations for the cases of sinus surgeries.