Local interventions for the management of alveolar osteitis (dry socket)

Alveolar osteitis (dry socket) is a complication of dental extractions and occurs more commonly in extractions involving mandibular molar teeth. It is associated with severe pain developing 2 to 3 days postoperatively, a socket that may be partially or totally devoid of blood clot and in some patients there may be a complaint of halitosis. It can result in an increase in postoperative visits.

To assess the effects of local interventions for the prevention and treatment of alveolar osteitis (dry socket) following tooth extraction.

The following electronic databases were searched: the Cochrane Oral Health Group Trials Register (to 29 October 2012), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2012, Issue 10), MEDLINE via OVID (1946 to 29 October 2012) and EMBASE via OVID (1980 to 29 October 2012). There were no restrictions regarding language or date of publication. We also searched the reference lists of articles and contacted experts and organisations to identify any further studies.

We included randomised controlled trials of adults over 18 years of age who were having permanent teeth extracted or who had developed dry socket post-extraction. 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 for the management of dry socket because these interventions are evaluated in separate Cochrane reviews.

Two review authors independently undertook risk of bias assessment and data extraction in duplicate for included studies using pre-designed proformas. Any reports of adverse events were recorded and summarised into a table when these were available. We contacted trial authors for further details where these were unclear. We followed The Cochrane Collaboration 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 instead. We used the GRADE tool to assess the quality of the body of evidence.

Twenty-one trials with 2570 participants met the inclusion criteria; 18 trials with 2376 participants for the prevention of dry socket and three studies with 194 participants for the treatment of dry socket. The risk of bias assessment identified six studies at high risk of bias, 14 studies at unclear risk of bias and one studies at low risk of bias. When compared to placebo, rinsing with chlorhexidine mouthrinses (0.12% and 0.2% concentrations) both before and after extraction(s) prevented approximately 42% of dry socket(s) with a RR of 0.58 (95% CI 0.43 to 0.78; P < 0.001) (four trials, 750 participants, moderate quality of evidence). The prevalence of dry socket varied 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 with (0.12% and 0.2%) chlorhexidine rinse to prevent one patient having dry socket (NNT) was 232 (95% CI 176 to 417), 47 (95% CI 35 to 84) and 8 (95% CI 6 to 14) for control prevalences of dry socket of 1%, 5% and 30% respectively.Compared to placebo, placing chlorhexidine gel (0.2%) after extractions prevented approximately 58% of dry socket(s) with a RR of 0.42 (95% CI 0.21 to 0.87; P = 0.02) (two trials, in 133 participants, moderate quality of evidence). The number of patients needed to be treated with chlorhexidine gel to prevent one patient having dry socket (NNT) was 173 (95% CI 127 to 770), 35 (95% CI 25 to 154) and 6 (95% CI 5 to 26) for control prevalences of dry socket of 1%, 5% and 30% respectively.A further 10 intrasocket interventions to prevent dry socket were each evaluated in single studies, and therefore there is insufficient evidence to determine their effects. Five interventions for the treatment of dry socket were evaluated in a total of three studies providing insufficient evidence to determine their effects.

Most tooth extractions are undertaken by dentists for a variety of reasons, however, all but three studies included in the present review included participants undergoing extraction of third molars, most of which were undertaken by oral surgeons. There is some evidence that rinsing with chlorhexidine (0.12% and 0.2%) or placing chlorhexidine gel (0.2%) in the sockets of extracted teeth, provides a benefit in preventing dry socket. There was insufficient evidence to determine the effects of the other 10 preventative interventions each evaluated in single studies. There was insufficient evidence to determine the effects of any of the interventions to treat dry socket. The present review found some evidence for the association of minor adverse reactions with use of 0.12%, 0.2% and 2% chlorhexidine mouthrinses, though most studies were not designed 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 (though previous allergy to chlorhexidine was an exclusion criterion in these trials). In view of recent reports in the UK of two cases of serious adverse events associated with irrigation of dry socket with chlorhexidine mouthrinse, it is recommended that all members of the dental team prescribing chlorhexidine products are aware of the potential for both minor and serious adverse side effects.