Frontal sinus: is it a predictor for vertical malocclusions?

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.

Assessment of Frontal Sinus Volume and Cranial Base Length Based on Different Vertical Skeletal Patterns: A Cone Beam Computed Tomographic Study

Introduction Evaluating craniofacial growth is an essential component of orthodontic treatment, and it is assessed by examining the cranial base. The anterior cranial base is regarded as a stable structure, and the frontal sinus is also recognised as a contributing component in the formation of the cranial base. The frontal sinus, a cavity present in the frontal bone, displays variation in both size and shape and has an impact on the overall structure of the skull and face. This study aims to evaluate the impact of vertical skeletal pattern and gender on the volume of the frontal sinus. Materials and methodology In this study, 90 cone beam computed tomography (CBCT) scans from the record's section were included, comprising 46 males (55.44%) and 44 females (48.88%) aged 20 to 35 undergoing orthodontic treatment. The assessment involved evaluating vertical skeletal patterns using a lateral cephalogram derived from the CBCT scans, and volumetric analysis of the frontal sinus was conducted using Dolphin Imaging software (version 11.9; Dolphin Imaging and Management Solutions, Chatsworth, California). Statistical analysis was performed on the collected data using SPSS software, version 20.0 (IBM Corp., Armonk, NY). Pearson correlation, a one-way ANOVA test to determine any statistically significant differences between the means of both frontal sinus volume and cranial base length groups individually and an independent t-test to compare the sample means between the frontal sinus volume and cranial base length groups were performed. Results: A non-significant association was observed between frontal sinus volume and cranial base length in skeletal open bite (p = 0.73) and skeletal deep bite (p = 0.12) between males and females, which implies there is no substantial association between frontal sinus volume (p = 0.08) and cranial base length (p = 0.41) in the different vertical skeletal patterns.  Conclusion: Frontal sinus volume was similar in subjects with a skeletal open bite and a deep bite. Males and females did not show a difference in frontal sinus volume. Hence, it was concluded that frontal sinus volume and anterior cranial base cannot be used as parameters to predict vertical malocclusions.

The relationship between the dimensions of frontal air sinus and skeletal malocclusions: A systematic review and meta-analysis

Objective

The goal of this systematic review and meta-analysis was to assess whether the dimensions of the frontal air sinus correlate with skeletal malocclusion.

Study selection

PubMed, Scopus, Embase, and Google Scholar were searched for relevant studies published up to May 23, 2023. The review included observational and retrospective studies that compared the dimensions of the frontal air sinus between different skeletal malocclusions. The PECOS method was used in this study ("Population, Exposure, Comparator, Outcome, and Study design"). The search was done using the following English keywords: "frontal sinus" OR "lateral cephalometric" OR "malocclusion" AND "surface area".

Results

Seven studies were included, which involved 1101 participants, of whom 403 were class I, 375 were class II, and 323 were class III. These studies had a moderate risk of bias. The surface area of the frontal sinus in class III was significantly larger than in class I (standardized difference in means (SDM) = -0.971; 95 % CI = -1.147- -0.796; P < 0.001) and in class II (SDM = -1.535; 95 % CI = -1.732- -1.337; P < 0.001).

Conclusion

Class III malocclusion is associated with a larger surface area of the frontal sinus compared to classes I and II.

A cross-sectional study: correlation of forehead morphology and dentoskeletal malocclusion in Chinese people

BACKGROUND

The lateral profile is an important indicator of facial attractiveness. This study explored the general characteristics of the forehead profile and protrusion, and their relationship with related factors in structure and development.

METHODS

Four hundred fourteen Chinese participants in the Yangtze River Delta region were involved. Including 206 males (17.15 ± 7.68 years old) and 208 females (18.35 ± 8.06 years old); 94 children (8.54 ± 2.21 years old, ranging from 4 to 12 years old), 166 adolescents (14.83 ± 1.50 years old, ranging from 13 to 17 years old), and 154 adults (25.52 ± 4.89, 18 years or older). The frontal section of the forehead was used to explore its shape. The straight distance between the vertical line of the FH plane through the nasal root point and its parallel line, which is tangential to the forehead, indicates the forehead prominence. Frontal sinus width was measured using the method described by Mahmood.

RESULTS

The general shape of the forehead was straight and slightly bulged near the eyebrow arch in males but rounder in females. The average forehead protrusion in males was higher than that in females in adults. Significant differences in forehead protrusion between the dentoskeletal classifications and growth phases were notable. Frontal protrusion significantly correlated with frontal sinus depth, especially in males, adults, Class I, and those whose convex points were located in the lower section of the forehead.

CONCLUSIONS

Age, race, and sex affect the forehead protrusion and frontal sinus width. Forehead protrusion may be an indicator of dentoskeletal deformities in the early stage. And dentoskeletal deformities may impair the correlation between the frontal sinuses and forehead protrusion during development.

TRIAL REGISTRATION

This retrospective, cross-sectional study was reviewed and approved by the Research Ethical Committee (T2020008), and registered at ClinicalTrial.gov with an identified number (ChiCTR2100041913).

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.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13005-022-00308-3.