Using panoramic radiographs to assess the probability of causing oroantral communication following tooth removal. A retrospective cross-sectional study

Objectives: To preoperatively assess the probability of oroantral communication (OAC) following the removal of maxillary (pre)molars using panoramic radiographs (PAN) and to assess the OAC-rate. Materials and Methods: During a 4,5-year period, patient characteristics of removals of maxillary (pre-)molars were recorded: ‘sex’, age, ‘sidedness’, ‘type of tooth’, ‘reason for removal’’ and ‘occurrence of OAC’. On the PAN of OAC-cases and of 100 control cases, the ‘Fraction of the Root Overlapping the Maxillary Sinus’ (FROMS) was calculated. The OAC-rate was reported overall, per tooth type and for four diagnostic classes: A: no overlap, B: 0.1–25%, C: 25.1–50% and D > 50% overlap. Univariate tests and regression analysis were performed to test the association between OAC-rate and ‘FROMS’, ‘sex’, age, ‘sidedness’, ‘type of tooth’, ‘reason for removal’. Results: Of 2340 maxillary (pre-)molars removed, 112 resulted in OAC (OAC-rate of 4.8% (95%CI 3.9%-5.7%)) The FROMS diagnostic class was significantly associated with the OAC-rate (χ2 = 42.90 df3, p < 0.0001). For the four diagnostic classes the risk of OAC was (A) 1.0%, (B) 3.3%. (C) 10.1% and (D) 17.7%. The first molar showed highest OAC-rate with 7.0%. No association between OAC-rate and ‘sex’, age, ‘sidedness’, ‘type of tooth’, ‘reason for removal’ was found. Conclusions: FROMS is a valid indicator of OAC probability. The overall OAC-rate was 4.8% and was highest in first molar removal. Clinical Relevance. Dentists and oral surgeons using PAN to assess OAC probability, can anticipate possible OAC and counsel patients.