Is CBCT Helpful in Estimating the Risk for Oroantral Communication During Maxillary Posterior Tooth Extraction?

Background: Oroantral communication (OAC) is a perforation between the oral cavity and maxillary sinus, commonly occurring after maxillary posterior tooth extraction. The role of imaging in identifying high-risk cases remains unclear.

Purpose: The study aimed to estimate the association between periapical and cone beam computed tomography (CBCT) imaging with OAC exposure during maxillary posterior tooth extraction and evaluate the necessity of CBCT in clinical decision-making.

Study Design, Setting, And Sample: A retrospective cohort study was conducted at Wuhan University Stomatological Hospital (August 2022 to August 2024), including patients with maxillary posterior teeth near the sinus who had both periapical and CBCT imaging. The exclusion criteria included contraindications to extraction, maxillary anomalies, prior sinus surgery, incomplete imaging, or untreated sinusitis on CBCT.

Predictor Variables: The predictor variable in this study was the radiographic risk of OAC. For periapical images, pertinent findings were overlap between the root apex and the cortical border of the maxillary sinus floor and protrusion of the root apex into the sinus cavity. For CBCT, pertinent findings were the presence of either intact or disrupted bony continuity of the maxillary sinus floor as observed in sagittal or coronal views. Risk was defined as the presence or absence of these radiographic findings.

Outcome Variable: The primary outcome was the intraoperative occurrence of OAC, which is defined as the formation of an abnormal perforation between the oral cavity and the maxillary sinus during tooth extraction.

Covariates: The covariates were sex, age, and tooth.

Statistical Analyses: χ or Fisher's exact test was used. ORs with 95% CIs evaluated associations. P < .05 was significant.

Results: The sample was composed of 69 subjects with a mean age of 40.3 years (SD: 16.6) and 41 (59.4%) were male. There were 5 (7.2%) cases of OAC. On periapical imaging, the radiographic risk factor was not statistically significantly associated with OAC (P > .05). On CBCT imaging, continuity defects were associated with OAC (OR = 2.9, 95% CI: 2.1 to 4.1, P = .0072).

Conclusions And Relevance: The results of this study suggest that maxillary sinus floor bone continuity defects were associated with OAC; root protrusion on periapical radiographs is not. CBCT is advised when protrusion is present but unnecessary if only overlap is seen.