We found that both short- and long-term pain did not differ according to presence of sutures. Three similar studies have found better postoperative sequelae in non-sutured wounds. Osunde et al.  performed a randomized study on 83 patients with either multiple sutures or no sutures. Pain, edema and trismus were significantly higher in the Suture group up to Day 2, with no further difference up to Day 7. In our study, no significant difference was found up until Day 31. Another randomized controlled split-mouth study on 35 patients comparing a single stitch behind the second molar against no sutures found greater pain on the non-sutured side from Day 5 onwards, but this was non-significant before Day 5 . Finally, Mahat et al.  performed a randomized study of 48 patients with either hermetic sutures with separate stitches or without suture, showing that pain was statistically higher for the Suture group only on Day 1.
Smokers showed 3.65 times more complications than non-smokers. A systematic review suggested tobacco induced dry sockets, especially in the first 24 h , possibly due to the sucking motion during smoking dislodging the clot , or smoking leading to granulation tissues and a decreased local immune and inflammatory response . The postoperative antibiotics given in the Mahat et al. study, alongside thorough postoperative instructions, may have avoided dry sockets. Unfortunately, Osunde et al. excluded smokers from their study .
We found no between-group differences for trismus, painkiller consumption, postoperative complications and edema, similarly to Mahat et al. . In contrast, Alkadi et al. observed significantly better healing up to one month on the sutured side, but without difference in edema and bleeding between the two techniques, evaluated up to Day 7 . However, edema was significantly higher in the Suture group in the Mahat et al. study  when measured between the mandibular angle and the lateral cantus, whilst edema measured between the tragus and the labial commissure was not significantly different. Osunde et al. presented edema as the mean of the two measurements and found statistically less edema in the no-suture group until Day 2, but no difference between Day 3 and 7 . Alkadi et al. recorded edema on a six-point scale without statistical differences until Day 7 between the sutured and non-sutured sides .
We found no difference between groups in quality of life. Considering postoperative quality of life relative to limitation of daily activities, measured as return to work the day after surgery, Mahat et al. only found this limitation in the Suture group . Excessive pain or social interaction limitation could likely be extrapolated as inability to work, but could vary between people.
The heterogeneity of the studies means they should be compared with caution. Our study was unique in offering anxiolytic premedication and general anesthesia; the others used local anesthesia with or without intravenous sedation [4, 5]. A major strength of our study was the multicentric design, with several operators and evaluators, whereas other studies used a single surgeon who also performed the outcome evaluation [4, 5]), or a single operator and several evaluators . We only gave prophylactic antibiotic treatment, whereas Osunde et al.  and Mahat et al.  applied a postoperative antibiotic therapy and Alkadi et al.  gave both prophylactic antibiotic treatment and antibiotic therapy. Mahat et al.  and Osunde et al.  made mesial relief incisions combined with a multiple-stitch silk thread suture, requiring subsequent removal. In contrast, Alkadi et al. opted for an incision without mesial relief and a single-stitch vicryl resorbable suture , as we did.
The number of teeth requiring removal and extent of impaction also differed between studies. These differences can lead to bias in comparison with these studies, particularly with Mahat et al.  due to the difference between totally and partially impacted third molar as a starting point concerning the difficulty of surgery or severity of the final wound.
This study had several limitations. Despite randomization, sex ratio and smoking prevalence appeared different between groups, both of which could potentially alter the results. However, adjustment on smoking status was planned in the protocol. Hence, the potential bias of smoking was accounted for in the results. Patients completed the questionnaires on Day 31, retrospectively recording the period starting from Day 2, which could explain the high scores even after several weeks. The practitioner was informed of the randomization arm at the beginning of surgery. Waiting until the end of the intervention to reveal the group could have avoided a bias. We did not note the type of suture used, however, certain studies have shown differences between different types of suture [4,5,6].
Questions remain over the best surgical techniques to use during extraction. A meta-analysis failed to find a superior technique on postoperative sequelae using different shaped access flaps . In contrast, a meta-analysis of mucous closure techniques highlighted a significantly favorable effect on edema of a closure preceded by exeresis of a gingival flap, disto-vestibular to the second molar compared with a classical hermetic mucous closure . Gay-Escoda et al.  found no significant postoperative differences between a mesial slot incision, sutured hermetically or not.
Surgical drainage presents an interesting avenue for further study, but is little used, with no real agreement as regards pain, edema or trismus . A 2012 systematic review comparing hermetic suture techniques with various closure protocols favoring secondary healing (drainage, gauze strip, single-stich suture and exeresis of a mucous flap) could not confirm the superiority of one technique over another for impact of edema, trismus, postoperative complications and pain . A Cochrane review found that antibiotic prophylaxis decreased the risk of infections, with a RR of 0.34 [95% CI 0.19–0.64], and also reduced occurrence of dry socket . However, the results were inconclusive on the effect on pain. Nevertheless, this reduced risk needs to be balanced against the advice to limit antibiotics to avoid resistance .
Finally, numerous studies have broached the question of adjuvant surgery to improve sequelae. Brković et al.  found that ropivacaine as supplemental injection provides a longer duration of postoperative analgesia, compared to placebo. Sub-mucosal dexamethasone injection had a significant beneficial postoperative effect on pain and trismus on the operating site , although there was no difference in late pain between the sub-mucosal, intravenous or intramuscular routes of administration . Installation of a collagen sponge in the alveoli statistically significantly reduced pain [21, 22]. A recent randomized controlled study found that ibuprofen and nimesulide produced better pain scores compared with acetaminophen, ketoprofen and dexamethasone when given as preemptive analgesia .
A meta-analysis studying the contribution of PRF (Platelet-rich Fibrin) in the sockets confirmed significant improvement regarding pain, edema and onset of osteitis . A study demonstrated greater efficacy of irrigating the site with chlorhexidine versus saline solution and iodinated povidone on reducing postoperative pain, edema and trismus . Reyes-Gilabert et al.  identified a statistically significant association between pre- and postoperative anxiety and also between postoperative anxiety and pain in oral surgery. Therefore preoperative per os sedation could be beneficial. In our case, patients had been given preoperative bromazepam.