Relationship between maxillary posterior molar roots and the maxillary sinus floor: Cone-beam computed tomography analysis of a western Chinese population

Evaluation of maxillary sinus changes following molar distalization using clear aligners: A three-dimensional study

OBJECTIVE

To evaluate the impact of molar distalization with clear aligners (CAs) on maxillary sinus parameters and its proximity to the root apices of maxillary molars using Cone Beam Computed Tomography (CBCT).

METHODS

The study involved pre- and post-treatment CBCT images of 27 adult patients. MIMICS 21.0 software was used to measure maxillary sinus volume and surface area, while Invivo Dental 6.0 program was used to measure the sinus diameters and proximity of the maxillary molar root apices to the sinus floor.

RESULTS

Post-treatment, there was a marked increase in the average volume and surface area of the maxillary sinus on both sides; however, changes in dimensions were not statistically significant. Sinus proximity to the root apices of the maxillary molars showed statistically significant differences, particularly on the left side for all roots. Gender and age impacted the outcomes, with males and younger individuals showing more pronounced changes. No significant differences were observed between the left and right sinuses in all parameters.

CONCLUSION

Molar distalization with CAs increases maxillary sinus parameters, more notably in younger and male patients. All molar teeth roots moved toward the sinus, particularly the mesiobuccal root of the maxillary second molar protruded to the sinus.

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.

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.

Diagnosis of Odontogenic Maxillary Sinusitis by Cone-beam Computed Tomography: A Critical Review

INTRODUCTION

This review aims to provide an up-to-date overview of the current applications of cone-beam computed tomography (CBCT) and other imaging modalities in diagnosing odontogenic maxillary sinusitis (OMS). Furthermore, the clinical operation procedures of radiography modalities in OMS diagnosis were summarized, with the goal of assisting clinicians in improving OMS diagnostic accuracy in clinical practice.

METHOD

A comprehensive review of researches that discussed the applications of radiography modalities in the diagnosis of OMS was conducted. Pertinent information was evaluated and organized for this review.

RESULTS

Cone-beam computed tomography (CBCT) offers a superior, high-resolution, and three-dimensional view of the maxillary tooth-bone-sinus complex compared to conventional radiography modalities. It enables a better understanding and classification of the spatial relationships between root apices/periapical lesions and maxillary sinus. The use of CBCT, combined with the advantages of other radiography modalities and proper image interpretation, is indispensable to enhance OMS diagnostic accuracy and mitigate the risk of missed or misdiagnosis.

CONCLUSION

The significance of CBCT in the diagnosis of oral and maxillofacial conditions has garnered widespread recognition. It provides highly precise diagnostic information and classification basis for OMS. The clinical operation procedures for imaging examination are essential in ensuring the consistency and reliability of the diagnosis.

Evaluation of the relation between the maxillary sinus and the posterior teeth using digital panoramic radiography

This research aimed to determine the relationship between the maxillary posterior teeth and maxillary sinus floor (MSF), as well as the impact of nearby tooth loss on the space between MSF and posterior maxillary roots. A number of 120 digital panoramic radiographs were obtained from the archives of several clinics in Al-Najaf, Iraq, with the overall teeth examined in these radiographs including 236 of the 1st premolars, 227 of the 2nd premolars, 227 of the 1st molars, and 231 of the 2nd molars, from the right and left sides. The distances between the apices of the teeth and the maxillary sinus were determined. There are three categories of relationships between upper posterior teeth roots and MSF. These include type Os (root apex exists below or outside MSF), Type Co (root apex in contact with the MSF), and Type Is (root apex above or inside MSF). Type Os is the most encountered among premolars, Type Co is mostly encountered among the 2nd molars, and Type Is, in the 1st and 2nd molars. The study finds no correlation between age, gender, and the distribution of maxillary posterior tooth roots attached to the MSF. The first premolars were the furthest from MS, while the first molars were the closest. The most frequent link between maxillary molar roots and the MS was the Co-relation for the 2nd maxillary molar and the Is relation for the 1st maxillary molar. There is a non-significant decrease in the distance between the apices of the 1st maxillary premolar, 2nd maxillary premolar, and 1st maxillary molar and the MS before and after extraction.

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.

Morphological Changes in Total and Inferior Part of Maxillary Sinus After Le Fort I Osteotomy, as Determined by Cone-Beam Computed Tomography

To investigate morphological changes of the total and inferior part of the maxillary sinus following Le Fort I osteotomy. 21 skeletal class II and 49 skeletal III patients who underwent orthognathic surgery were enrolled in this retrospective study. Cone-beam computed tomography taken before (T1) and 6 to 24 months after (T2) orthognathic surgery were imported into Mimics 20.0 software to analyze morphological changes of the total and inferior part of the maxillary sinus. Volume of the whole maxillary sinus was significantly reduced after surgery ( P ≤0.008), while the volume of the inferior part of the maxillary sinus was significantly greater than before surgery ( P ≤0.004). Maxillary sinus floor moved occlusally after Le Fort I osteotomy. Movement in the pitch direction of the posterior maxilla affected the state of the maxillary sinus mucosa after orthognathic surgery. Le Fort I osteotomy exerts a significant impact on the morphology of the total and inferior part of the maxillary sinus.

[Relationships between the inferior wall of maxillary sinus and the roots of the maxillary molars]

OBJECTIVE

The aim of the study is to evaluate the position of the roots of the first and second upper molars relative to the bottom of the maxillary sinus (maxillary sinus) according to cone-beam computed tomography (CBCT).

MATERIAL AND METODS

The CBCT scans of 150 patients (69 men and 81 women) from the database of the X-ray department of the 11th City Clinical Hospital of Minsk who applied for dental care were studied. There are 4 variants of vertical relationships between the roots of the teeth and the lower wall of the maxillary sinus. At the contact of the molar roots and the bottom of the HPV, 3 variants of the horizontal relationship between the roots of the teeth and the bottom of the maxillary sinus in the frontal plane were identified.

RESULTS

The root apices of the maxillary molars can be located below the level of the MSF (type 0; 16.69%), contact with MSF (types 1-2; 72%) or protrude into the sinus cavity (type 3; 11.31%) at a distance of up to 6.49 mm. The roots of the second maxillary molar showed greater proximity to the MSF than the first molar roots and more often protruded into the maxillary sinus. The most common type of horizontal relationship between the molar roots and the MSF, in which the lowest point of the MSF was located centrally between buccal and palatal roots. It was found that the proximity between the roots and the MSF correlates with maxillary sinus vertical dimension. This parameter was significantly greater in type 3 when the roots protruded into the maxillary sinus than in type 0, when there was no contact between the MSF and the root apices of the molar teeth.

CONCLUSION

Significant individual variability in the anatomical relationships between the roots of the maxillary molars and the MSF indicates the need for the mandatory appointment of cone-beam computed tomography in preoperative planning for the extraction of these teeth and/or their endodontic treatment.

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.

Three-dimensional assessment of the favorability of maxillary posterior teeth intrusion in different skeletal classes limited by the vertical relationship with the maxillary sinus floor

Background

Understanding the anatomical relationship between the maxillary sinus floor (MSF) and the posterior maxillary teeth (PMT) is important when planning the orthodontic intrusion of the posterior teeth. This study aimed to determine the vertical relationship between posterior maxillary teeth and maxillary sinus floor in different skeletal classes in the Chinese adult population.

Methods

This is a retrospective cross-sectional study involved cone beam computed tomography images of 298 adult patients (145 males and 153 females) between 20 and 45 years old. The sample was categorized according to A point, Nasion, B point (ANB) angle into 102 Class I, 102 Class II, and 94 Class III malocclusion. Non-parametric Wilcoxon Mann–Whitney U and Kruskal–Wallis tests were used to compare the studied groups. The Intra-class Correlation Coefficient (ICC) was used to assess the intra- and inter-observer reliability analysis.

Results

Overall, there was a statistically significant difference in the mean distance between both genders (P < 0.001). The measured distance increased with age in all posterior tooth roots (P < 0.001). The root apex in the sagittal view appeared to be closer to the maxillary sinus than in the coronal view; 2.2 ± 4.3 and 3.1 ± 5.5 mm, respectively. The most frequent root scores were Type 1 and Type 2P. In both sagittal and coronal views, Class I demonstrated a higher Type 2P prevalence, whereas Class III showed a lower prevalence. The second molars’ mesiobuccal root had the largest number of penetration in the three examined skeletal classes.

Conclusions

Maxillary molars of Class I malocclusion with the majority of Type 2P root-sinus relationship have the highest possible risk of root resorption during molar intrusion due to cortical bone encroachment, while Class III malocclusion showed the least possible risk.

Supplementary information

The online version contains supplementary material available at 10.1186/s13005-022-00316-3.

Tumor-Infiltrating CD4+ Central Memory T Cells Correlated with Favorable Prognosis in Oral Squamous Cell Carcinoma

OBJECTIVE

Oral squamous cell carcinoma (OSCC) is the most frequent oral malignancy with a poor prognosis, in which tumor-infiltrating immune cells may play a critical role. Therefore, our study aims to screen potential immune cells and immune-related genes for predicting OSCC prognosis.

METHODS

A total of 310 OSCC patients with full transcriptional data and clinical characteristics were extracted from the TCGA database. Then, we obtained their abundance of tumor-infiltrating immune cells on TIMER 2.0 and analyzed them using xCell method. Univariate and multivariate Cox regressions were applied successively to identify the immune cells associated with overall survival of OSCC patients. Furthermore, we screened the prognostic genes that related to the identified immune cells and validated their expressions by immunohistochemistry.

RESULTS

CD4+ central memory T (TCM) cell was recognized as the sole independent immune cell correlated with OSCC prognosis (p = 0.0085). A novel nomogram based on CD4+ TCM cell abundance was established for predicting the prognosis of OSCC patients, with calibration plots showing good performance for 1-, 3-, 5-year overall survival. Thirty-four related prognostic genes were screened according to the differential abundance of CD4+ TCM cell infiltration. In immunohistochemistry analysis, DEFB1 showed a significant positive relationship with the density of CD4+ TCM cells (p = 0.0075).

CONCLUSION

CD4+ central memory T cell was proposed as an independent prognostic biomarker for OSCC patients. DEFB1 might positively regulate the abundance of tumor-infiltrating CD4+ TCM cells, thus improving OSCC prognosis. Our findings may provide a new insight into better prognosis prediction and precise medicine for OSCC.

Space closure by miniscrew-assisted mesialization of an upper third molar and partial vestibular fixed appliance: A case report

This case report demonstrates how the use of skeletal anchorage and appropriate orthodontic biomechanics can be used to resolve even complex cases, reducing unwanted dental movements and allowing the use of a partial vestibular appliance. It describes the complete mesialization of the left upper third molar and space closure following extraction of tooth UR7, due to vertical fracture one year after previous endodontic therapy for caries. This therapeutic choice was conditioned by the need not to alter the good pre-existing interarch relationships, and above all by the patient's request to be treated conservatively, and therefore not to undergo prosthetic implant rehabilitation. The use of orthodontic miniscrews and the careful application of orthodontic biomechanics, based on both direct and indirect anchorage, enabled the treatment objectives to be achieved in a reasonable period of time with reduced treatment costs.

Location of the Maxillary Posterior Tooth Apices to the Sinus Floor in an Egyptian Subpopulation Using Cone-beam Computed Tomography

Introduction

The aim of this study was to evaluate the location of the apices of the maxillary posterior teeth to the maxillary sinus floor (MSF), the symmetry between both sides and the possible variations between males and females using cone-beam computed tomography (CBCT) in an Egyptian subpopulation.

Materials and Methods

CBCT images were collected from 120 patients (240 second premolars, 480 1^st and 2^nd molars, 1680 roots). The proximity of roots of maxillary second premolar and 1^st and 2^nd molars to the floor of the sinus was categorized into three categories: inside the sinus floor (IS), touching the sinus floor (TS) or outside the sinus floor (OS). The correlation of the distance with gender was analyzed as well as for symmetry. Friedman's test was used to compare between different roots and the Dunn's test was used for pair-wise comparisons when Friedman's test was significant. The Mann-Whitney U test was used to compare males and females. The significance level was set at P≤0.05.

Results

The highest prevalence of roots outside the sinus was found with second premolar (right and left) followed by palatal roots of right and left second molar. In addition, the highest prevalence of roots inside the sinus was found with mesiobuccal roots of maxillary second molar followed by the palatal root of maxillary first molar. There was no statistically significant difference between males and females or between both sides.

Conclusion

Neither gender nor side variations regarding the proximity to the maxillary sinus floor were observed.

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.

CBCT-based assessment of the anatomic relationship between maxillary sinus and upper teeth

Objectives

To describe the relationship between maxillary sinus (MS) and upper teeth based on cone beam computed tomographic scans (CBCT).

Materials and methods

Based on CBCT maxillary imaging data of 147 patients, distance between MS and apices of canines and posterior maxillary teeth were assessed. Distances between tooth roots and sinus were classified into three groups: distant (>2 mm), close (<2 mm) or in contact with MS. Teeth with apical lesions and uncommon root configurations were excluded.

Results

In total, 1075 teeth of maxillary canines, upper premolars and upper molars were included in this study. Teeth most often in contact with MS were the second (89%) and first (81%) maxillary molar without any significant difference (p = 0.19). Roots most often in contact with MS were the mesiobuccal and distobuccal root of the second molar (85% and 76%; p = <0.01) followed by the palatal root of the first molar (73%). A fifth of the upper canines are situated less than 2 mm from MS.

Conclusions

More than four out of five upper molars (first and second) are in a close relationship to the MS. Knowledge of the anatomical relationship between posterior maxillary teeth and the MS is important for diagnosis and treatment in this area.

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.