Background: Incidence and severity of postoperative complications are key elements in determining the risk‐benefit relationship of any surgical procedure. The aim of this retrospective study was to assess and categorize the postoperative complications that occur following, and are associated with, oral, periodontal, and implant surgeries.

Methods: A total of 3,900 patients who underwent surgical procedures including, but not limited to, sinus floor elevation, guided tissue regeneration, crown lengthening, implant placement, soft tissue graft, open flap debridement or surgical removal of impacted teeth were included. Postoperative complications were recorded and graded based on impedance to routine daily activity and favorable surgical outcomes. Regression models were generated to evaluate correlations between complication types, as well as between patient/surgical characteristics and the incidence of complications.

Results: Surgical removal of impacted teeth and lateral sinus floor elevation had the highest incidence and severity of complications. Postoperative dentinal hypersensitivity (5.7%) was the most frequent complication, followed by excessive pain (4.1%), and moderate postoperative bleeding (3.5%). Based on the devised grading system described in this paper, the complications were 11.1% of Grade I, 3.3% of Grade II, 8.3% of Grade III, 0.1% of Grade IV, and no complications recorded under Grades V or VI.

Conclusions: Surgical removal of impacted teeth and lateral sinus floor elevation are more prone to more severe complications compared with other procedures. Additionally, complications that do not impede favorable surgical outcomes and/or routine daily activity are the most likely to occur. Smoking and diabetes are generally associated with postoperative complications.