Evaluation of the relationship between the maxillary sinus floor and the root apices of the maxillary posterior teeth using cone-beam computed tomographic scanning

AI model to detect contact relationship between maxillary sinus and posterior teeth

Objectives

To establish a novel deep learning networks (MSF-MPTnet) based on panoramic radiographs (PRs) for automatic assessment of relationship between maxillary sinus floor (MSF) and maxillary posterior teeth (MPT), and to compare accuracy of MSF-MPTnet, dentists and radiologists identifying contact relationship.

Study design

A total of 1035 PRs and 1035 Cone-beam computed tomographys （CBCT）images were collected from January 2018 to April 2022. The relationships were classified into class I and II by CBCT. Class I represents non-contact group, and class II represents contact group. 350 PRs were randomly selected as test dataset and accuracy of MSF-MPTnet, dentists, and radiologists was compared.

Results

The intraclass correlation coefficient of dentists was 0.460-0.690 and it was 0.453-0.664 for radiologists. Sensitivity and accuracy of MSF-MPTnet were 0.682-0.852and 0.890-0.951, indicating that the output performance of MSF-MPTnet was reliable. Accuracy of maxillary premolars and molars were 79.7%-90.3 %, 76.2%-89.2 % and 72.9%-88.3 % in MSF-MPTnet model, dentists and radiologists. Accuracy of class I relationship in the MSF-MPTnet model (67.7%-94.6 %) was higher than that of dentists (56.5%-84.6 %) in maxillary first premolars and right second premolar, and accuracy of class I relationship in the MSF-MPTnet model is also higher than radiologists (40.0%-78.1 %) in all teeth positions (p < 0.05).

Conclusions

MSF-MPTnet model could increase detecting accuracy of the relationship between MSF and MPT, minimize pseudo contact relationship and reduce frequency of CBCT use.

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.

Morphometric analysis of the relationship between maxillary posterior teeth and maxillary sinus floor in central Indian population: A cone-beam computed tomography study

Background

The relationship between the maxillary sinus (MS) and the root apices of posterior teeth is of significant clinical relevance as it influences the diagnosis and treatment planning when operating in the posterior areas of the maxilla. The aim of this study, therefore, is to assess this anatomic relationship and evaluate the propensity of roots of posterior maxillary teeth to be intruded into the MS space using cone-beam computed tomography (CBCT) scanning.

Materials and Methods

One thousand CBCT scans of patients, aged 20 years or above, were analyzed in the study. The distance from the MS floor to the root apices of the posterior teeth was measured and the relationship between the MS and the posterior teeth roots were recorded, based on Kwak's and Didilescu's classification.

Results

Based on Kwak's classification, type I configuration was frequently observed in the maxillary posterior teeth, followed by type II. Based on Didilescu's classification, the longest distance, among premolars, was observed between the palatal root of the left 1st premolar and MS, i.e., 8.2467 mm. Among molars, the longest distance was observed between mesiobuccal root of the right first molar and MS, i.e., 5.8966 mm. The shortest distance, among premolars, was observed between the buccal root of the left second premolar and MS, i.e., 3.5500 mm, and among molars, the shortest distance was between the mesiobuccal root of the left second molar and MS, i.e., 1.3556 mm.

Conclusion

From the present study, it may be concluded that, among the central Indian population, mesiobuccal root of the second molars and buccal root of the second premolars show the closest proximity to the MS floor. Therefore, any surgical or endodontic intervention in the vicinity of these roots must be performed with utmost care.

Epoxy vs. Calcium Silicate-Based Root Canal Sealers for Different Clinical Scenarios: A Narrative Review

This study aimed to review the considerations for choosing a suitable sealer according to various endodontic scenarios. An electronic search of PubMed, Scopus, and the Web of Science was undertaken for the keywords of 'sealer choosing', 'appropriate sealer', 'suitable sealer', 'sealer for clinical scenario', and 'sealer for clinical situations'. However, the literature review revealed a lack of studies with practical clinical recommendations regarding the choice of appropriate endodontic root canal sealers for particular clinical situations of root canal treatment. Therefore, a narrative review was undertaken under the basis of the characteristics of an epoxy resin-based sealer (ERS) versus a calcium silicate-based sealer (CSS). Based on the evidence found through the review, the choice of an appropriate sealer in a variety of clinical scenarios was proposed. An ERS is recommended for one-visit non-vital cases, teeth with periodontal involvement, cracked teeth, and internal root resorption without root perforation. A CSS is recommended for vital or non-vital cases in multiple visits, teeth with internal root resorption with perforation or internal approach for external cervical resorption, teeth with open apices, and teeth with iatrogenic aberrations.

Characteristics of CBCT versus panoramic signs of the surrounding bone of molar root protrusions into the maxillary sinus

The study aimed to (a) investigate the amount and characteristics of the surrounding bone of protruded molar roots into the maxillary sinus using cone-beam computed tomography (CBCT) and (b) assess the correlation between the amount of bone with panoramic high-risk signs. Radiographs of 408 roots protruding beyond the sinus floor were evaluated. Axial CBCT images were used to investigate then classify eight characteristics of surrounding bone: no bone; bone < half the root girth in the proximal or buccal-palatal aspect; bone covering half the root girth in the proximal or buccal-palatal aspect; bone > half the root girth in the proximal or buccal-palatal aspect; and, complete bone. These were then grouped into four degrees of bone support: no bone; bone ≤ half the root girth; bone > half the root girth; and, complete bone. Panoramic signs were subclassified as: projection of root; interruption of the sinus floor; darkening of the root; upward curving of the sinus floor; absence of periodontal ligament space; and, absence of the lamina dura. Correlation between the degree of bone and the panoramic signs was evaluated using the Chi-square or Fisher's exact tests. Positive and negative predictive values, sensitivity, specificity, accuracy, and receiver operating characteristic analysis were calculated. Complete bone support was the most common. 'Projection of root' had a high negative predictive value and sensitivity. 'Absence of the periodontal ligament space and lamina dura' had a high positive predictive value, specificity, accuracy, and area under the curve. These two signs were significantly correlated with the degree of bone support.

Adjacent tooth migration after maxillary first molar loss in patients with sinus augmentation: A retrospective research

PURPOSE

The objectives of this study are to: (1) investigate the extent of antagonistic and distal neighboring tooth migration in the maxillary posterior single tooth-missing site during the healing period of bone augmentation and implant surgery; (2) identify factors associated with tooth migration.

MATERIALS AND METHODS

One hundred and forty-three cases that lost the maxillary first molar were included, and their CBCT data during the edentulous period were obtained. Dentition models were reconstructed from CBCT, and superimpositions were performed, followed by measuring migration distances and calculating migration rates of antagonistic and distal neighboring teeth. Factors were analyzed using multivariate generalized estimating equations (GEE).

RESULTS

The mean migration distances were 208 ± 137 μm and 403 ± 605 μm for antagonistic teeth and distal teeth, and the mean migration rates were 26.8 ± 21.2 μm/month and 48.5 ± 76.7 μm/month, respectively. One hundred and nineteen out of 143 distal neighboring teeth migrated toward the edentulous site, and all antagonistic teeth migrated occlusally. Occlusal contact loss and chronic apical periodontitis both significantly accelerated antagonistic tooth migration (p < 0.05), the latter also accelerated distal tooth migration (p < 0.05). Besides, the displacement of the distal teeth was somewhat accelerated by the impacted adjacent third molar and root protrusion into the sinus.

CONCLUSIONS

The neighboring teeth tend to migrate toward the edentulous gap in the maxillary posterior region. Occlusal contact loss and chronic apical periodontitis are two significant risk factors for accelerating antagonistic tooth migration, and for distal teeth, chronic apical periodontitis is the risk factor. The impacted adjacent third molar and root protrusion into the sinus are also potential risk factors for accelerating the migration of the maxillary distal tooth. Thus, to prevent maxillary edentulous gap reduction, the factors mentioned above should be taken into consideration when planning treatment flow.

Endo-Periodontal Lesions-An Overlooked Etiology of Odontogenic Sinusitis

The aim of this study was to analyze the oral etiology of patients with odontogenic sinusitis (ODS) and to compare the differences in demographic data, clinical symptoms, extent of sinus involvement, bone penetration of the maxillary sinus floor (MSF) between different etiologies. A retrospective investigation was conducted on 103 patients with ODS recruited from Beijing TongRen Hospital. All enrolled patients underwent sinus CT, nasal endoscopy, and oral examination. A comparison of the patients' clinical symptoms, the extent of involvement of the sinuses, and bone resorption of the MSF according to odontogenic etiologies was conducted. Follow-up was based on symptoms and clinical examination. The most common odontogenic etiologies were endo-periodontal lesions (EPLs, 49.5%), apical periodontitis (AP, 32.0%), and periodontitis (PE, 8.7%). There were statistically significant differences in age (p = 0.002), sex (p = 0.036), inflammation involving the ethmoid sinus (p = 0.037), and bone penetration of the MSF (p < 0.001) between the AP, EPL, and PE groups. There were no significant differences in sinusitis symptoms (p > 0.005) among patients with different odontogenic etiologies. In conclusion, EPL is a neglected oral etiology with a destructive effect on the bone of the MSF, which deserves more attention in diagnosis and treatment.

Prevalence and pattern of proximity of maxillary posterior teeth to maxillary sinus with mucosal thickening: A cone beam computed tomography based retrospective study

Context

Odontogenic sinusitis is a prevalent but frequently unrecognized condition, and periapical pathologies of maxillary posterior teeth are accused as one of the main causative factors.

Aim

This study aimed to evaluate the relationship between the periapical status of maxillary posterior teeth and its proximity to the maxillary sinus floor in the occurrence of incidental sinus pathologies using cone-beam computed tomography (CBCT).

Methodology

CBCT scans of 118 patients of age range 18-77 years were evaluated retrospectively to determine the relationship of maxillary posterior teeth to sinus floor in which vertical relationship was assessed using modified Kwak's classification and periapical status using CBCT periapical index. Statistical analysis was performed using SPSS statistics software.

Results

Of all 227 sinuses examined, 56.8% showed pathological changes, with mucosal thickening being the most common. More than 50% (50.2%) of sinuses were associated with periapical lesions of at least one maxillary posterior tooth based on evidence of pathological mucosal thickening. The presence of pathologic mucosal thickening was also significantly related (P < 0.05) to the presence of periapical pathologies. There was a significant association between tooth position and pathological sinus mucosal thickening, especially with second molars, first molars, and second premolars, respectively (P < 0.05). Second molar involvement was the most significant (P < 0.05).

Conclusion

The present study established a positive association between periapical disease status of maxillary posteriors and maxillary sinus mucosal thickening. Maxillary second premolar and first and second molars pathologies can significantly affect the maxillary sinus compared to other maxillary posterior tooth. CBCT proved to be an efficient imaging modality in detecting these changes.

Anatomical Evaluation of Posterior Maxillary Roots in Relation to the Maxillary Sinus Floor in a Saudi Sub-Population: A Cross-Sectional Cone-Beam Computed Tomography Study

To evaluate the mean distance and differences between posterior maxillary teeth and maxillary sinus floor (MSF) concerning the age and gender of the patients, a total of 124 maxillary sinuses and 496 posterior maxillary teeth were randomly selected in 62 cone-beam computed tomography (CBCT) images. Mean distances between posterior maxillary roots (PMRs) from different teeth and the MSF were measured using a calibrated tool in the software. Other relations regarding the gender and age of the patients were determined. The mean root-MSF distances in the right and left first premolars were more significant compared to the second premolars. No significant relation was found between the apices of the right and left first and second molar roots and the floor of the maxillary sinus concerning gender. A statistically significant relation was found between the apices of the buccal root of the right first premolar, right and left first and second molars and floor of the maxillary sinus concerning the age group 21-40 years (p-value = 0.009). This study showed that the second molar mesiobuccal root apex is frequently related to the sinus floor. Differences were reported concerning age, concerning the distance between posterior maxillary teeth and the maxillary sinus floor. CBCT technology helped provide the clinical proximity between the MSF and the posterior teeth root apices during the treatment planning.

Analysis of the root position and angulation of maxillary premolars in alveolar bone using cone-beam computed tomography

Purpose

This study investigated whether the relationship between the maxillary sinus and the root of the maxillary premolar is correlated with the root position and whether there is a difference in the long axis angle of premolars and the buccal bone thickness according to the sinus-root relationship and root position.

Materials and Methods

Cone-beam computed tomographic images of 587 maxillary first premolars and 580 second premolars from 303 patients were retrospectively reviewed. The maxillary sinus floor-root relationship was classified into 4 types, and the root position in the alveolar bone was evaluated as buccal, middle, or palatal. The long axis angle of the maxillary premolars in the alveolar bone and the buccal bone thickness were measured. The correlation between these parameters was analyzed.

Results

The maxillary sinus floor-root relationship showed a statistically significant correlation with the root position in the alveolar bone. Most maxillary first premolars were buccally located, and more than half of the second premolars had their roots in the middle. The long axis angle of the premolars was significantly larger in buccal-positioned teeth than in middle-positioned teeth, and the buccal bone was thinner.

Conclusion

When the root of the maxillary premolar was separated from the sinus floor, the premolar was often located on the buccal side. Most of the maxillary first premolars had a thinner buccal bone and larger inclination than the second premolars. It is recommended to evaluate the root position, sagittal angle and buccal bone thickness using CBCT for implant treatment planning.

Maragathavalli. Assessment of the vertical relationship between the maxillary posterior teeth and the maxillary antral floor in a South Indian population using Cone Beam Computed Tomography- A radiographic observational study

Introduction and Aim: Maxillary sinus, also known as the Antrum of Highmore, is said to be one of the largest pyramidal shaped paranasal sinuses that begins at the 10th week of intrauterine development and undergoes pneumatisation. The root apices of the maxillary posterior teeth have a proximity to the antral floor, so a thorough understanding of this anatomical relationship is very essential as it can have an important influence during dental procedures such as implant planning, extractions, and certain other oral and maxillofacial surgeries. The aim of this study was to assess the vertical relationship between the posterior teeth in the maxillary arch with the floor of the maxillary antrum, using Cone Beam Computed Tomography (CBCT) in a South Indian population.   Materials and Methods: This was a retrospective analysis of 50 right or left maxillary sinuses in panorama and tangential sections by tracing the outline forms of the maxillary antral floor and also measuring its vertical distance from maxillary posterior root apices.   Results: Four types of relationship patterns were observed between the maxillary antral floor and root apices of the maxillary posteriors. The root apices of the maxillary second molar were found to be in close proximity with the maxillary sinus (2.27mm) and similar observation was found in the left side with the left second molar to be in close proximity to the sinus (2.04 mm).   Conclusion: The assessment of this vertical relationship is very important during extractions, implant planning or during any other surgeries in the maxillofacial region.

Relationship of the maxillary posterior teeth and maxillary sinus floor in different skeletal growth patterns: A cone-beam computed tomographic study of 1600 roots

Purpose

This study evaluated the distance from the posterior root apices to the maxillary sinus floor (MSF) and the frequency of roots touching or protruding through the MSF using cone-beam computed tomography (CBCT).

Materials and Methods

This study included 100 subjects divided into different vertical and anteroposterior skeletal growth patterns. On CBCT images, the distance from the posterior root apices to MSF was measured and the frequency of roots touching or protruding through the MSF was evaluated using NNT software (version 5.3.0.0; ImageWorks, Elmsford, NY, USA).

Results

No statistically significant differences were found in the distance from the posterior root apices to the MSF among vertical skeletal groups (P>0.05). The palatal roots of the first molar and the palatal, mesio-buccal and disto-buccal roots of the second molars had significantly less distance from MSF in skeletal class II than in class III (P<0.05). The high-angle group had the highest frequencies of roots touching or protruding into the maxillary sinus (49.8%); the lowest proportion of these roots was found in skeletal class III (28.3%) and the highest proportion in class II (50.3%). Males had shorter distances from the posterior root apices to the MSF and higher frequencies of roots protruding through or touching the MSF than females.

Conclusion

Anteroposterior skeletal growth patterns and sex affected the distances from the maxillary posterior roots to the MSF. The frequency of roots protruding into or touching the sinus was affected by both vertical and anteroposterior skeletal groups and sex. These findings have implications for dental practice.

Vertical relationships between the divergence angle of maxillary molar roots and the maxillary sinus floor: A cone-beam computed tomography (CBCT) study

AIM

To assess the relations between the divergence angle of the maxillary molar roots and their proximity to the maxillary sinus floor using CBCT.

METHOD

This study comprised CBCT scans of the maxilla, including at least the inferior one-third of the maxillary sinus and at least one molar present in any quadrant with complete eruption and root formation. Evaluation included the vertical relations between the maxillary molar root apices and the maxillary sinus floor (MSF), and the root divergence was measured from the root apices to the floor of the pulp chamber. The chi-square test was used for the associations between the study parameters. For the correlation between root divergence angles and MSF vertical relationship types, the Spearman test was used. A P-value < 0.05 was considered significant.

RESULTS

A total of 100 scans were analyzed, including 316 permanent maxillary first and second molars. The MSF Type II vertical relationship was the most prevalent (39.6%), followed by Type I (31.3%). The highest divergence angle was found between the distobuccal and palatal roots (mean = 44.9 ± 10.5°). For the mesiobuccal-distobuccal angle groups, there were higher percentages of the MSF Type I and II relationships among the angle groups < 1° and 21-45°. For the mesiobuccal-palatal angle groups, a higher prevalence of the MSF Type II relationship was found in the <21⁰ and >45⁰ angle groups, and a higher prevalence of the Type I relationship was found in the 21-45⁰ angle group. For the distobuccal-palatal angle groups, higher percentages of the MSF Type II relationship were found in the three angle groups. For all teeth, there was a significant positive correlation between the MSF vertical relationship and the mesiobuccal-palatal angle (r = 0.116; P = 0.039).

CONCLUSION

There was a positive correlation between the divergence angle of the roots and their vertical relationship with the MSF. Clinicians should assess the divergence between the roots before performing extraction or endodontic treatments.

Intrusion of maxillary molar roots into the maxillary sinus in a sample of the Egyptian population using cone beam computed tomography

Background

The proximity of the maxillary sinus floor to the maxillary molar roots increases the probability of oroantral communication on conducting any surgical or endodontic procedure in the involved area. The aim of this study is to evaluate the relationship between each maxillary molar root and maxillary sinus floor using cone beam computed tomography. Predicting the probability of protrusion of each root into the sinus will consequently predict the probability of occurrence of the oroantral fistula in a sample of the Egyptian population.

Results

The total number of roots located outside the sinus was 121 (35.3%), while those contacting the sinus floor were 80 (23.3%) and those intruded the sinus were 141 (41.2%). The percentage of root intrusion into the sinus in males (56.9%) was significantly (p = 0.01) higher than females (42.9%). The probability of root intrusion in the left molars (54.2%) was non-significantly (p = 0.067) higher than that of the right side (44.3%). As for the type of tooth, the second molar showed the highest probability of root intrusion into the sinus (55.3%) followed by the third molars (52.6%) then the first molars (40.9). According to the type of root, the mesiobuccal root showed the highest probability of intrusion into the sinus (50.9%) followed by the palatal root (49.1%) then the distobuccal root (47.4%). However, the difference in both type of tooth and type of root was statistically non-significant (p = 0.051 and 0.869 respectively). As for the individual root with the highest probability of intrusion, the mesio-buccal root of the right third molar is the most frequent root to intrude the sinus (71.4%) and the mesio-buccal root of the right first molar is the least frequent (22.7%).

Conclusions

In a sample of the Egyptian population, males exhibit higher probability of root protrusion into the sinus than females. The side and type of tooth are of higher impact on the probability of its intrusion into the sinus compared to the type of root. Left second molars are at a higher risk of oroantral communications on surgical or endodontic procedures compared to other molars due to its highest probability of intrusion into the sinus.

Comparison of panoramic radiography and cone-beam computed tomography for assessing radiographic signs indicating root protrusion into the maxillary sinus

Purpose

This study investigated correlations between findings on panoramic radiographs and cone-beam computed tomography (CBCT) to assess the relationship between the maxillary sinus floor and the roots of maxillary posterior teeth. In addition, radiographic signs indicating actual root protrusion into the maxillary sinus were evaluated on panoramic radiographs.

Materials and Methods

Paired panoramic radiographs and CBCT images from 305 subjects were analyzed. This analysis classified 2,440 maxillary premolars and molars according to their relationship with the maxillary sinus floor on panoramic radiographs and CBCT images. In addition, interruption of the sinus floor was examined on panoramic radiographs.

Results

Root protrusion into the maxillary sinus occurred most frequently in the mesiobuccal roots of the second molars. The classification according to panoramic radiographs and CBCT images was the same in more than 90% of cases when there was no contact between the root apex and the sinus floor. When the panoramic radiograph showed root protrusion into the sinus, the CBCT images showed the same classification in 67.5% of second molars, 48.8% of first molars, and 53.3% of second premolars. There was a statistically significant relationship between interruption of the sinus floor on panoramic radiographs and root protrusion into the sinus on CBCT images.

Conclusion

The presence of root protrusion into the sinus on panoramic radiographs demonstrated a moderate ability to predict root protrusion into the maxillary sinus. Interruption of the maxillary sinus floor could be considered an indicator of actual root protrusion into the maxillary sinus.

Investigating the anatomical relationship between the maxillary molars and the sinus floor in a Chinese population using cone-beam computed tomography

Background

The anatomical relationship between the root apices of maxillary molars and the maxillary sinus floor (MSF) is important for the treatment of dental implantations and endodontic procedures. In this study, the detailed anatomical relationships between the root apices of maxillary molars and the MSF were studied in a Chinese population using CBCT.

Methods

We collected the CBCT data files of patients who visited the stomatology outpatient clinic in Shanghai Fifth People’s Hospital, Fudan University from January 1, 2017 to January 1, 2019 and measured the following items: the distance between the molar root apices and the MSF, the thickness of the mucosa and cortical bone of the MSF closest to the root apices, and the angle between the buccal and palatal roots.

Results

The shortest distances between the root apices and the MSF were 1.57 ± 3.33 mm (the mesiobuccal root of the left second molar) and 1.61 ± 3.37 mm (the mesiobuccal root of the right second molar). Apical protrusion over the inferior wall of the sinus most often occurred in the mesiobuccal root of left second molar (frequency, 20.5%). The mucosa of the MSF was thinnest at the distobuccal root of the right second molar (1.52 ± 0.85 mm), the cortical bone of the MSF was thinnest at the mesiobuccal root of the right second molar (0.46 ± 0.28 mm), and the angle between the buccal and palatal roots ranged from 12.01° to 124.2° (42.36 ± 24.33 °).

Conclusions

Among the root apices of the maxillary molars, the mesiobuccal root apex of the left second molar was closest to the MSF, and it had the highest incidence of protrusion into the sinus. The unique anatomical relationship between the maxillary molars and the MSF in this Chinese population is critical for treatment planning for dental implantation or endodontic procedures.