The objective of this study was to evaluate the quality of life (QoL) and degree of satisfaction among adult outpatients after surgical extraction of a lower third molar under local anaesthesia, and to assess the impact of thorough explanation of the anticipated postoperative course on their pain and daily activities. Ninety-two patients filled a questionnaire assessing social isolation, working isolation, eating ability, speaking ability, sleep impairment, physical appearance, discomfort at suture removal and overall satisfaction on days 4 and 7 after surgery. A 100-mm visual analogue scale (VAS) of pain was scored by the patients every day after extraction until day 7. Before extraction, patients were randomly allocated to one of two groups: the test group received detailed verbal instructions from a surgeon about the postoperative course after extraction of the third molars, together with a written text containing postoperative instructions. One day after extraction, they were asked by telephone about their status. The control group only received the written text with postoperative instructions, with a few basic oral explanations. Ninety-one patients (53 of them female) completed the questionnaires. The decrease in pain was linear over time. Men referred significantly less pain than women, but there were no statistically significant differences between the test and control groups. The test group was characterized by a significantly greater inability to work. Lower third molar surgery significantly affects patient quality of life and environment, particularly during the first 3 days after extraction.