The aim of this research is to study the effect of probiotic supplements (Lactobacillus reuteri) on post-surgical complications and oral wound healing after extraction of impacted third molars.

Healthy volunteers are consecutively randomized to the test or placebo group. After a standardized surgical procedure, conducted under local anesthesia, the participants are instructed to take three lozenges daily (one in the morning, one at lunch time and one in the evening) containing either two strains of L. reuteri (DSM 17938 and ATCC PTA 5289; >108 CFU per lozenge) or placebo for 2 weeks. The subjects are instructed to let the tablet slowly melt in the oral cavity and to fill in a personal log-book on a daily basis throughout the postoperative period. The patients are recalled to the clinic for follow-up after 1, 2 and 3 weeks for examination. The post-surgical events (pain, swelling, discomfort, feeding problems) are registered daily by the patient in a custom-made logbook. Furthermore, the type and frequency of painkillers and antibiotic prescriptions are noted in the logbook. At the follow-ups, the healing of the wounds/lesions is scored with a clinical healing index. Stimulated saliva samples are collected at baseline and after 2 weeks and kept frozen until further analysis. In addition, smear samples are collected after 1 and 2 weeks from the extraction socket for bacterial analysis. Any subjectively perceived side- or adverse effect in connection with the intervention should be reported to the surgeon. The participants are encouraged to maintain their normal tooth brushing habits.

Inclusion Criteria:

• Uncompromised general health
• Non-smoker
• No systemic medications (except contraceptives)
• No recent/ongoing episode of antibiotic treatment.

Exclusion Criteria:

• Any pathological condition associated with the third molars detected on radiographs prior to surgery
• Regular consumers of probiotics