The effect of leaving dentures in place on bag-mask ventilation at induction of general anesthesia.

BACKGROUND: The optimum timing for denture removal in edentulous patients before anesthesia and surgery is uncertain. METHODS: We conducted a prospective, randomized, controlled trial to evaluate the effect of leaving dentures in during bag-mask ventilation at induction of general anesthesia. One hundred sixty-six edentulous patients were randomized to two groups. The Dentures-In group was bag-mask ventilated after induction of anesthesia with dentures left in place. The Dentures-Out group patients had their dentures removed before bag-mask ventilation. The degree of difficulty of bag-mask ventilation was assessed by the anesthesiologist. RESULTS: Successful bag-mask ventilation, as defined by a increase in ETco(2) to 20 mm Hg and back to baseline with 3 L/min fresh gas flow and the adjustable pressure limiting valve at 20 cm H(2)O, was achieved in 61 of 84 (73%) of the Dentures-In patients compared with 40 of 81 (49%) of the Dentures-Out patients (odds ratio 0.37, 95% CI = 0.19-0.70, P = 0.002). CONCLUSION: We conclude that bag-mask ventilation is easier in edentulate patients when their dentures are left in situ during induction of general anesthesia.