Understanding curative effects of periapical curettage through antrum canals.Method 68 affectedteeth appearing antrum canal after treatment of pulp canal have been cured directively by periapical curettage of sinus cannal

and they are interviewed and observed.Results 61 cases are cured successfully

the percentage is 89.7%.7 are losing and all are grinding teeth.Conclusion Periapical curettage through antrum canals is operated simply

with the low recurence rate

and it is a good method to preserve affected teeth and adaption for basic dental surgery ambulatorium.