Cleft lip and palate cause large variations in size and location of the posterior superior alveolar canal.

OBJECTIVE The aim of this study was to evaluate the posterior superior alveolar canal (PSAC) in patients with cleft lip and palate (CLP) as compared to patients with no cleft lip and palate (NC) using cone-beam computed tomography (CBCT). MATERIALS AND METHODS This was a retrospective multicenter study based on two steps: (1) evaluating intra- and inter-calibration and (2) detecting the presence or absence of PSAC and its location, diameter, and anastomosis with anterior superior alveolar canal. RESULTS A total of 300 patients were selected for the study, out of which 150 were categorized as CLP (75 men, 75 women; mean age: 29.8 years) and 150 were categorized as NC (75 men, 75 women; mean age: 40.3 years). PSAC in patients with CLP and NC was visible in 100% of the cases, in men and women, bilaterally. PSAC location in CLP was middle and upper third of the maxillary sinus as compared to NC (lower third) (chi-squared < 0.001). PSAC mean diameter in CLP was 1.12 mm. It was larger compared to 0.6 mm in NC (t-test < 0.0001). CONCLUSION PSAC location in patients with CLP was predominantly in the middle and upper third of the maxillary sinus, compared with NC. PSAC mean diameter in CLP was 1.12 mm. It was larger compared to that of 0.6 mm in NC. CLINICAL RELEVANCE These anatomical variations in CLP are important and should be acknowledged by surgeons for the following reasons: (1) to perform pre-surgical planning, (2) to avoid bleeding, and (3) to avoid neurosensory alterations.