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

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.

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 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.