BACKGROUND

Alveolar osteitis (dry socket) is a complication of dental extractions more often involving mandibular molar teeth. It is associated with severe pain developing 2 to 3 days postoperatively with or without halitosis, a socket that may be partially or totally devoid of a blood clot, and increased postoperative visits. This is an update of the Cochrane Review first published in 2012.  OBJECTIVES: To assess the effects of local interventions used for the prevention and treatment of alveolar osteitis (dry socket) following tooth extraction.

SEARCH METHODS

An Information Specialist searched four bibliographic databases up to 28 September 2021 and used additional search methods to identify published, unpublished, and ongoing studies.

SELECTION CRITERIA

We included randomised controlled trials of adults over 18 years of age who were having permanent teeth extracted or who had developed dry socket postextraction. We included studies with any type of local intervention used for the prevention or treatment of dry socket, compared to a different local intervention, placebo or no treatment. We excluded studies reporting on systemic use of antibiotics or the use of surgical techniques because these interventions are evaluated in separate Cochrane Reviews.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. We followed Cochrane statistical guidelines and reported dichotomous outcomes as risk ratios (RR) and calculated 95% confidence intervals (CI) using random-effects models. For some of the split-mouth studies with sparse data, it was not possible to calculate RR so we calculated the exact odds ratio (OR) instead. We used GRADE to assess the certainty of the body of evidence.

MAIN RESULTS

We included 49 trials with 6771 participants; 39 trials (with 6219 participants) investigated prevention of dry socket and 10 studies (with 552 participants) looked at the treatment of dry socket. 16 studies were at high risk of bias, 30 studies at unclear risk of bias, and 3 studies at low risk of bias. Chlorhexidine in the prevention of dry socket When compared to placebo, rinsing with chlorhexidine mouthrinses (0.12% and 0.2% concentrations) both before and 24 hours after extraction(s) substantially reduced the risk of developing dry socket with an OR of 0.38 (95% CI 0.25 to 0.58; P < 0.00001; 6 trials, 1547 participants; moderate-certainty evidence). The prevalence of dry socket varies from 1% to 5% in routine dental extractions to upwards of 30% in surgically extracted third molars. The number of patients needed to be treated (NNT) with chlorhexidine rinse to prevent one patient having dry socket was 162 (95% CI 155 to 240), 33 (95% CI 27 to 49), and 7 (95% CI 5 to 10) for control prevalence of dry socket 0.01, 0.05, and 0.30 respectively.  Compared to placebo, placing chlorhexidine gel intrasocket after extractions reduced the odds of developing a dry socket by 58% with an OR of 0.44 (95% CI 0.27 to 0.71; P = 0.0008; 7 trials, 753 participants; moderate-certainty evidence). The NNT with chlorhexidine gel (0.2%) to prevent one patient developing dry socket was 180 (95% CI 137 to 347), 37 (95% CI 28 to 72), and 7 (95% CI 5 to 15) for control prevalence of dry socket of 0.01, 0.05, and 0.30 respectively. Compared to chlorhexidine rinse (0.12%), placing chlorhexidine gel (0.2%) intrasocket after extractions was not superior in reducing the risk of dry socket (RR 0.74, 95% CI 0.46 to 1.20; P = 0.22; 2 trials, 383 participants; low-certainty evidence).  The present review found some evidence for the association of minor adverse reactions with use of 0.12%, 0.2% chlorhexidine mouthrinses (alteration in taste, staining of teeth, stomatitis) though most studies were not designed explicitly to detect the presence of hypersensitivity reactions to mouthwash as part of the study protocol. No adverse events were reported in relation to the use of 0.2% chlorhexidine gel placed directly into a socket. Platelet rich plasma in the prevention of dry socket  Compared to placebo, placing platelet rich plasma after extractions was not superior in reducing the risk of having a dry socket (RR 0.51, 95% CI 0.19 to 1.33; P = 0.17; 2 studies, 127 participants; very low-certainty evidence).  A further 21 intrasocket interventions to prevent dry socket were each evaluated in single studies, and there is insufficient evidence to determine their effects. Zinc oxide eugenol versus Alvogyl in the treatment of dry socket Two studies, with 80 participants, showed that Alvogyl (old formulation) is more effective than zinc oxide eugenol at reducing pain at day 7 (mean difference (MD) -1.40, 95% CI -1.75 to -1.04; P < 0.00001; 2 studies, 80 participants; very low-certainty evidence) A further nine interventions for the treatment of dry socket were evaluated in single studies, providing insufficient evidence to determine their effects.

AUTHORS' CONCLUSIONS: Tooth extractions are generally undertaken by dentists for a variety of reasons, however, all but five studies included in the present review included participants undergoing extraction of third molars, most of which were undertaken by oral surgeons. There is moderate-certainty evidence that rinsing with chlorhexidine (0.12% and 0.2%) or placing chlorhexidine gel (0.2%) in the sockets of extracted teeth, probably results in a reduction in dry socket. There was insufficient evidence to determine the effects of the other 21 preventative interventions each evaluated in single studies. There was limited evidence of very low certainty that Alvogyl (old formulation) may reduce pain at day 7 in patients with dry socket when compared to zinc oxide eugenol.