The purpose of this study is to determine whether pulp chamber opening and drainage on wisdom teeth with acute pulpitis before the extraction could reduce postoperative pain so beneficial to patient.

Inclusion Criteria:

• inclusion criteria of upper wisdom teeth for the two groups were: vertical eruption; being worthless to be restored; deep caries in the occlusion surface with acute pain; without caries or acute pulpitis in the adjacent second molar

Exclusion Criteria:

• systemic diseases, smokers, inflammation in oral cavity,with history of psychiatric illness,pregnant or lactating females

patients requiring surgical removal of a single upper wisdom tooth with acute pulpitis were included in this prospective study