Cephalometric association of mandibular size/length to the surface area and dimensions of the frontal and maxillary sinuses

Association of Vertical Facial Patterns With Maxillary Sinus Volume in Skeletal Class I Adults: A Cross-Sectional Cone-Beam Computed Tomographic Study

Introduction The morphology of the maxillary sinus (MS) is influenced by craniofacial growth patterns, with vertical skeletal discrepancies potentially affecting MS volume. This study aimed to compare MS volume across normodivergent, hyperdivergent, and hypodivergent individuals, and to evaluate the correlation between MS volume, the mandibular plane angle, and vertical maxillary height. Materials and methods This retrospective, cross-sectional study included 60 adult patients (age > 18 years) with a skeletal class I pattern and fully erupted permanent dentition. The patients were divided equally into three groups (n = 20 each): normodivergent, hyperdivergent, and hypodivergent, based on the mandibular plane angle. Cone-beam computed tomography (CBCT) scans were obtained and analyzed using ITK-SNAP software for semi-automatic segmentation of MS volume (in mm³) and linear measurements of the anterior and posterior vertical maxillary heights (in mm). The bilateral MS volumes were measured independently by two calibrated examiners to ensure reliability. Statistical analysis was performed using ANOVA, Pearson correlation coefficient, and post-hoc Tukey tests (p < 0.05). Results The mean age was comparable across the groups (p > 0.05). No significant differences were found between the right and left MS volumes within groups, indicating bilateral symmetry. However, significant differences in MS volume and vertical maxillary height were observed across the groups (p < 0.05). Hyperdivergent patients exhibited significantly larger MS volumes and greater anterior and posterior vertical maxillary heights than hypodivergent patients. The normodivergent individuals had intermediate values. A moderate positive correlation was found between the mandibular plane angle and posterior vertical maxillary height (p = 0.016), whereas a stronger correlation was found with anterior maxillary height (p = 0.001). The MS volume showed a stronger positive correlation with vertical maxillary height than with the mandibular plane angle. Conclusion MS volume was significantly influenced by vertical maxillary height rather than the mandibular plane angle. Hyperdivergent individuals exhibited larger MS volumes and greater vertical maxillary heights compared to hypodivergent and normodivergent individuals. These findings highlight the role of vertical craniofacial dimensions in sinus morphology and may inform clinical decisions regarding orthodontics and maxillofacial surgery.

Correlation Between Facial Asymmetry and Maxillary Sinus Size or Volume Using Dental Cone-Beam Computed Tomography Images

Objectives This study investigated correlations between facial asymmetry and left-right differences in maxillary sinus size and volume, as well as their relationships with skeletal morphology. Methods The participants were 154 Japanese adults (56 men, 98 women) aged 18 to 38 years (mean age, 24.1 ± 5.3 years). Cone-beam computed tomography (CBCT) images were analyzed using InVivo™ 6 software (Anatomage, Inc., San Jose, CA, USA). Facial asymmetry was assessed at six landmarks: orbitale, condylion, and gonion (all bilateral); anterior nasal spine; deepest point in bony concavity (B point); and menton (at midline). Maxillary sinus height, width, length, and volume were measured. Participants were classified into skeletal classes (I, II, III) and vertical growth patterns (horizontal, average, vertical). Spearman's rank correlation coefficient was used to assess the relationships of these six facial asymmetry landmarks with differences in maxillary sinus linear measurements and volume. Results The facial asymmetry index was positively correlated with maxillary sinus length in the condylion region and height in the gonion region. As left-sided facial deviation increased, the right maxillary sinus became larger; conversely, as right-sided facial deviation increased, the left maxillary sinus became larger. Thus, the maxillary sinus on the nondeviated side tends to be larger. Vertical facial growth patterns showed greater maxillary sinus height and volume in the vertical growth group than in the average growth group. Conclusions Asymmetry in specific facial regions may be associated with region-specific variations in maxillary sinus morphology, and vertical skeletal patterns may influence maxillary sinus development. These findings offer insights into the relationship between facial asymmetry and maxillary sinus structure.

Analysis of Frontal Sinus Dimensions According to the Skeletal Malocclusion in German Teenagers

The present study explored the association between the craniofacial sagittal skeletal patterns and frontal sinus dimensions in Germans. This cross-sectional study included orthodontic patients with age ranging from 11 to 18 (80 males, 82 females). Lateral cephalograms were used in the cephalometric and frontal sinus analysis. Cephalometric analysis was performed to measure SNA, SNB and ANB angles. Frontal sinus measurements were performed to obtain the frontal sinus height, antero-posterior dimension and frontal sinus lateral projection area. The frontal sinus dimensions were compared between genders with Mann Withney test. Kruskal Wallis and Dunn's post-hoc tests were used to compare the mean differences between the skeletal malocclusions. Spearman's correlation test and linear regression model were also performed. Statistical significance was set at 5%. Regarding skeletal malocclusion, 71 patients presented class I, 81 class II and 10 class III skeletal malocclusion. The frontal sinus height (p=0.009), frontal sinus antero-posterior dimension (p=0.001) and frontal sinus lateral projection area (p=0.007) were bigger in males than in females. The frontal sinus antero-posterior dimension was significantly greater in the class III when compared to the class I (p=0.010) and class II (p=0.027). Frontal sinus lateral projection area was also bigger in class III than class I (p=0.039). In the linear regression model a significant association was observed between frontal sinus lateral projection area and class III (skeletal class I as a reference). In conclusion, our result suggests that the frontal sinus lateral projection area might present morphometric differences in German teenagers with skeletal class III malocclusion.

Is There Variation in the Morphology of the Frontal Sinus in Individuals with Different Craniofacial Patterns? A Systematic Review with Meta-Analysis

To evaluate differences in the morphology of the frontal sinus in adolescents and adults with different craniofacial patterns, searches up to April 2024 were conducted in six databases and other information sources to identify observational studies. Study selection, data extraction, and quality assessment using the NOS scale were performed independently by two reviewers. Random effects meta-analyses were conducted to estimate the difference in frontal sinus measurements between different craniofacial skeletal patterns (α = 0.05). The certainty of the evidence was evaluated according to GRADE. Fourteen studies were included in the review. All studies had methodological limitations that affected their quality. The syntheses showed that skeletal Class II subjects presented a significantly smaller width of the frontal sinus than skeletal Class I subjects (MD = 0.56; 95% CI: 0.38, 0.74; p < 0.0001; I2 = 3%). Skeletal Class III subjects showed a frontal sinus width (MD = -0.91; 95% CI: -1.35, -0.47; p < 0.0001; I2 = 36%) and area (MD = -28.13; 95% CI: -49.03, -7.23; p = 0.0084; I2 = 66%) significantly larger than those of the skeletal Class I subjects. The available evidence suggests a positive relationship between mandibular and frontal sinus size. There is limited evidence to make reliable estimates of the association of other craniofacial patterns and frontal sinus characteristics. These reported results are not conclusive and should be evaluated carefully due to the very low certainty of the evidence. The current evidence is scarce and consists of studies with methodological limitations; the results of the studies are often inconsistent, and the pooled estimates are imprecise. New high-quality research is still necessary.

Evaluation of Dimensional Changes in Maxillary and Frontal Sinus in Adult Patients With Anterior Open Bite and Normal Overbite: A Retrospective Cone Beam Computed Tomography (CBCT) Study

INTRODUCTION

An anterior open bite is a form of vertical discrepancy that presents as a lack of contact between maxillary and mandibular segments. The treatment modalities usually involve either intrusion of posterior teeth or extrusion of anterior or a combination of both. The anatomical relationship between the apex of the maxillary molar roots to the inferior wall of the maxillary sinus floor is crucial in planning posterior intrusion. The paranasal sinuses influence the growth of the facial structures that eventually get altered in various malocclusions. Studies have proven that the height of the sinus gets modified in anterior open bite owing to pneumatization. This study aims to evaluate the distance from the root apex of maxillary first molars (mesiobuccal, distobuccal, and palatal roots) to the maxillary sinus floor to evaluate the significance of the vertical pneumatization of the sinus on planning for true intrusion in anterior open bite and to assess the correlation between frontal and maxillary sinuses in an anterior open bite.

METHODS

This retrospective study evaluated 30 pre-treatment cone beam computed tomographies (CBCTs) of patients out of which 15 were with anterior open bite and 15 with ideal overbite. Linear measurements were carried out using care stream software in CBCTs.

RESULTS

There was a significant correlation between the distance of the palatal root and the distobuccal root of the maxillary first molar to the maxillary sinus floor bilaterally in the anterior open bite (p<0.04). A significant moderate positive correlation of the maxillary and frontal sinus height in anterior open bite (p<0.006). A significant moderate negative correlation between the distance from the palatal root to the maxillary sinus floor and maxillary sinus height in anterior open bite (p<0.001).

CONCLUSION

Vertical pneumatisation of the maxillary sinus has caused a significant negative correlation between the apex of the palatal root of the maxillary first molar tooth and the maxillary sinus floor in the anterior open bite. The palatal root being the closest to the sinus floor, and the distobuccal root being second nearest. There is a significant correlation between the height of the sinuses in the anterior open bite.

The Evaluation of Maxillary Sinus Dimensions in Different Craniofacial Patterns: A Systematic Review and Meta-Analysis

This systematic review was intended to evaluate the maxillary sinus dimensions in vertical and sagittal craniofacial patterns and to assess if there was a difference among the craniofacial patterns. A systematic search was performed in seven databases till February 2021. The risk of bias was performed with modified Newcastle Ottawa scale. Meta-analysis was performed using random effects model. Twelve studies were included in the review and 8 in the meta-analysis. Compared to Class I malocclusion, the maxillary sinus area is greater in Class II and lesser in Class III malocclusion. On comparing normo-divergent growth pattern, the maxillary sinus area is lesser in hypo-divergent and greater in hyper-divergent individuals. Most of the studies were graded as satisfactory. The measurements are greater in hyper-divergent Class II malocclusion and in males.

The dimensional and morphological assessment of frontal air sinus in different ages, genders and ethnicities (Arabian-Caucasian and Han-Chinese sub-populations)

OBJECTIVE

This study aimed to assess the dimensional and morphological measurements of the frontal air sinuses in different ages and genders in the two ethnicities.

MATERIALS AND METHODS

This retrospective study included 360 subjects (160 males and 200 females) of both ethnicities. Subjects were divided based on age and gender into four groups, including an equal number of both males and females, for each age and ethnic group. The frontal air sinus dimensions were measured utilizing lateral cephalometric radiographs and computed using Winceph version 9.0 software. The frontal air sinus dimensions were compared between age groups in both genders and between ethnicity using an independent sample t test. The relationship between the frontal air sinus dimensions and subjects' age was evaluated using Pearson's correlation coefficient.

RESULT

The frontal air sinuses measurements were larger in males than females in both ethnicities, except for the frontal sinus index, which was found to be larger in females than males. The frontal air sinus surface area and height showed statistically significant differences between the two age groups in both ethnicities (P < 0.05). The Arabian-Caucasian patients had a larger frontal sinus surface area, height, and depth than the Han-Chinese patients in both age groups.

CONCLUSION

The size of the frontal air sinus increases with age; and continues to expand after the age of 20 years. Based on the Arabian-Caucasian and Han-Chinese sub-population findings, the frontal sinus is an effective tool for determining gender and appears to have potential in ethnicity identification.

A comparison of maxillary sinus diameters in Chinese and Yemeni patients with skeletal malocclusion

BACKGROUND

This study aimed to compare the maxillary sinus dimensions and surface area in accordance with skeletal malocclusion, gender and ethnicity factors in a sample of Chinese and Yemeni patients.

METHODS

This cross-sectional study analysed 180 maxillary sinuses using 180 lateral cephalometric radiographs. The patients were subdivided into two ethnic groups: Chinese and Yemeni. Each ethnic group comprised 90 patients, and men and women were divided equally. Each ethnic group was classified into three skeletal classes using ANB and Wits appraisal (skeletal Classes I, II and III). Pearson's correlation coefficient was also used to assess the relationship between maxillary sinus dimensions and cephalometric parameters.

RESULTS

Men had larger maxillary sinuses than women; skeletal Class II had a higher length and surface area increase than other skeletal classes, although skeletal Classes I and II were almost equal in height. Except for the maxillary sinus length, none of these findings were statistically significant. The maxillary sinuses in Chinese are larger than those in Yemenis (P = 0.000). These variables were positively correlated with SNA, SNB and Co-A. The maxillary sinus length and Co-Gn were positively correlated. The NA-APO and NA-FH angles were also correlated with the maxillary sinus surface area. However, the gonial and GoGn-Sn angles negatively affected the maxillary sinus dimension and surface area.

CONCLUSIONS

Men had larger maxillary sinuses than women in both ethnic groups, and Chinese individuals had larger maxillary sinuses than Yemenis. Skeletal Class II malocclusion of both ethnicities had larger maxillary sinus dimensions. Furthermore, the maxillary sinus dimensions correlated with cephalometric parameters.

The relationship between frontal sinus dimensions and skeletal malocclusion

Purpose

The aim of this retrospective research is to compare frontal sinus dimensions in skeletal Class I, skeletal Class II, and skeletal Class III individuals and to evaluate the relationship of these dimensions with anterior skull base length and some cephalometric values.

Materials and methods

In this research, we used lateral cephalometric radiographs of 60 people aged 17 to 25. In individuals with skeletal Class I malocclusion, skeletal Class II malocclusion due to mandibular insufficiency, and skeletal Class III malocclusion due to mandibular excess, measurements of frontal sinus length and height as well as S-N, Co-A and Co- Gn lengths, ANB0, FMA0, SN-GoGn0 angles values were performed. The length between the highest point and the lowest point of the frontal sinus was calculated as the height of the frontal sinus, and the length between the most anterior and the most posterior points of the frontal sinus was calculated as the length of the frontal sinus.

Results

The frontal sinus length and height were found to be higher in skeletal Class III individuals than in skeletal Class I and skeletal Class II individuals, however, there was no significant difference between skeletal Class I and Class II individuals.

Conclusion

The increase in frontal sinus height and length correlated positively with the decrease in the ANB angle and the increase in the SN and Co-Gn lengths. The dimensions of the frontal sinus may be an indicator for the remaining mandibular growth potential.

Volumetric Assessment of the Frontal Sinus in Female Adolescents and Its Relationship with Craniofacial Morphology and Orthodontic Treatment: A Pilot Study

The present study aimed to evaluate the correlation between frontal sinus morphology and craniofacial morphology, and to investigate the effects of orthodontic treatment on the development of the frontal sinus in female adolescents (mean age: 13.9 ± 1.3 years). In total, 53 patients were recruited and underwent cephalography and computed tomography before and after orthodontic treatment. Of these patients, most had a bilaterally symmetrical fan-shaped frontal sinus without any fusion. The average size and volume of the frontal sinus before orthodontic treatment were 45.8 ± 12.3 mm in breadth, 29.8 ± 7.3 mm in height, 22.7 ± 5.1 mm in depth, and 5151.6 ± 2711.4 mm² in volume. Sinus volume in patients with skeletal Class III malocclusion tended to be larger than that in patients with skeletal Class I and II malocclusion. Upon comparison with the pretreatment measurements, the sizes and volumes of the frontal sinus were significantly larger following orthodontic treatment, regardless of the skeletal pattern; however, since these changes were small, the increases in the size and volume of the frontal sinus may have been caused by pubertal growth and not orthodontic treatment. The clinical relevance of the frontal sinus remains controversial.

Morphological and dimensional variations of the frontal air sinuses in a group of adolescent Caucasians and Chinese in different skeletal malocclusions: a cross-sectional cephalometric study

OBJECTIVE

This study aimed to evaluate the morphological and dimensional variations of the frontal air sinuses in a group of adolescent Caucasians and Chinese with different skeletal malocclusions in both genders.

MATERIALS AND METHODS

This retrospective study included 290 adolescent Caucasians and Chinese patients with 145 each. Each sample included 90 females and 55 males and was categorized based on ANB angle in reference to each population norms into 65 skeletal class I, 50 skeletal class II, and 30 skeletal class III malocclusions. All linear, angular, and surface area measurements of the frontal air sinuses were evaluated using lateral cephalometric radiographs and calculated using Winceph version 8 software. The frontal air sinus parameters were compared between genders and the two ethnic groups using an independent sample t-test. ANOVA with Tukey's post hoc tests were used to compare the frontal air sinus parameters between the three skeletal malocclusions.

RESULT

The frontal air sinus width and surface area were found to be significantly greater in Caucasians when compared with Chinese patients. According to gender, the frontal air sinus length, width, and surface area, as well as the glabella convexity, were greater in males than females, while the frontal air sinus index (length/width) was significantly greater in females than males in both ethnic groups. In both ethnic groups, the frontal air sinus surface area was significantly greater in skeletal class III malocclusion when compared to skeletal class I and class II malocclusions in Caucasians (P = 0.0022) and Chinese (P = 0.0097). There was a weak-to-moderate correlation between the frontal air sinus parameters and the nasio, sella, and glabella positions (R = -0.56 to 0.62).

CONCLUSION

The frontal air sinus dimensions and surface area varied greatly in between ethnic groups, genders, and malocclusion types. The frontal air sinus parameters were correlated with nasion, sella, and glabella positions.

CLINICAL RELEVANCE

These findings could assist orthodontists, ENT specialist, and forensic medical investigators to focus on the size of frontal sinus during treatment planning, the relationship between the size of frontal air sinus and malocclusions, and age determination.

A CBCT based analysis of the correlation between volumetric morphology of the frontal sinuses and the facial growth pattern in caucasian subjects. A cross-sectional study

BACKGROUND

The aim of this study was to evaluate the relationship between frontal sinus shape and facial growth pattern.

METHODS

The three-dimensional examination was carried out by means of 80 CBCT scans selected from a sample of 1247 records of patients treated, for different reason, at the Department of Biomedical Surgical and Dental Sciences at University of Milan, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico Milan. The sample (age ranges between 12 and 40 years) was divided according to gender and age in four groups (12-17, 18-20, 21-30, 31-40). Left and right frontal sinus volume (VOL), surface (SUP) and linear maximum width (XMAX), depth (ZMAX) and height (YMAX) were calculated using Mimics Research 17.0 (Materialise N.V., Leuven, Belgium). Cephalometric analysis has been performed for all subjects to categorize the patients depending on their facial growth pattern. Univariate and multivariate regression analysis were performed to investigate any association of frontal sinuses measurements (height, width, depth, volume and surface) and cephalometric variables. P value < 0.05 was considered statistically significant.

RESULTS

A total of 160 frontal sinuses were measures in 80 patients: 40 men and 40 women, average age of 23.5 ±14.6. Globally the frontal sinuses had the following average dimensions: volumes of 9055.8 ± 6505 mm3 and surfaces of 3820.3 ± 2125 mm2. The statistical analysis showed that frontal sinus volume was statistically significant (p=0.003) greater for male (11,425 mm3) than female (6597.5 mm3). Similarly, the surface showed to be greater in men than in women (p=0.005). No correlation between age and frontal sinuses characteristics has been found. A statistically significant (p<0.05) increase of frontal sinus depth, surface and volume was correlated with SNB angle. In addition, frontal sinus volume increased in subjects with greater anterior skeletal dimension values and with a superior length of the cranial base. Furthermore, a decrease of ANB has been found related to an increase in frontal sinus volume (p=0.04).

CONCLUSIONS

The present study showed a correlation between frontal sinuses dimensions and craniofacial aspects, despite the inter-individual variability of their morphology. The results suggested that young adults in whom the frontal sinuses have reached their maximum size, while vertical growth continues, a larger frontal sinus may be associated with future vertical growth.

Standard orthodontic treatment after condylectomy for patients with active unilateral condylar hyperplasia

INTRODUCTION

Unilateral condylar hyperplasia (UCH) is a progressive, nonneoplastic overgrowth of the condyle of the temporomandibular joint. For treating active UCH, a popular method combines orthognathic surgery with high condylectomy and orthodontic treatment. The goal of this study was to introduce a new method to correct asymmetry for active UCH.

METHODS

Retrospectively, 47 patients with active UCH were divided into horizontal-type, vertical-type, and combined-type. All patients were treated with condylectomy plus postsurgery standard orthodontics (CPSO) with applied miniscrews implanted in infrazygomatic crest and hard palate to intrude affected side of maxillary molars and apply intermaxillary traction for contralateral molars. Cone-beam computed tomography was taken at presurgery, postsurgery, and the end of orthodontics (T3).

RESULTS

In the vertical (n = 10) and combined (n = 28) types, deviation of the chin and the canting of the mandible and maxillary occlusal plane were significantly reduced at T3. A difference in the torque of bilateral maxillary first molar (U6) and bilateral mandibular first molar (L6) was significantly reduced at T3. The anterior, superior, and posterior joint spaces in the vertical-type and combined-type were significantly decreased at T3 compared with postsurgery. In contrast, in the horizontal-type group (n = 9), the deviation of the chin was corrected; however, the canting of the mandible and maxillary occlusal plane was significantly increased at T3 compared with presurgery.

CONCLUSIONS

CPSO restored facial and occlusal symmetry for vertical-type and combined-type active UCH and returned affected-side condyle to the glenoid fossa. However, CPSO was not suitable for treating the horizontal-type UCH.