Moderate evidence to recommend submucosal injection of dexamethasone in reducing post-operative oedema and pain after third molar extraction.

Data sourcesThe electronic databases searched included: PubMed/MEDLINE, Cochrane Central Register of Controlled Trials (Central) and Web of Science until June 2015. There was no restriction to language and the reference lists from relevant studies were searched for further articles.Study selectionRandomised and prospective controlled trials that compared the effect of submucosal injection of dexamethasone with that of placebo after impacted third molar surgery in humans. Studies involving volunteers with decompensated metabolic disease were excluded.Data extraction and synthesisStudy selection, data extraction and quality assessment (risk of bias) were assessed by two reviewers. All disagreements were resolved through discussion. A meta-analysis was performed for all continuous variables (oedema, pain and trismus) when at least two of the studies analysed the same data type.ResultsEight studies involving a total of 476 patients of which six were included in the meta-analysis. All of the surgical procedures were performed on the lower molars, submucosal injections of dexamethasone were used in concentrations of 4 mg, 8 mg, or 10 mg, and saline was used as a control. Antibiotic medications were administered prophylactically before surgery or by continuous use after the procedure. Seven of the eight studies identified the impactions according to the Pell and Gregory Classification. Oedema was measured using facial contours of pre-established reference points. The meta-analysis presented a mean difference (MD) of -2.20 (95% CI -2.70 to -1.70), with a statistically significant difference favouring dexamethasone (P< 0.00001). Trismus (assessed using inter-incisal distance upon maximum opening) had a MD of -2.92 (95% CI -7.13 to 1.29) and showed no statistically significant difference between groups. Pain was assessed using both visual analogue scales and number of analgesic taken; however, only studies including a VAS were used for meta-analysis. Pain presented with a MD of -1.79 (95% CI -3.28 to -0.30) and showed a statistically significant difference favouring dexamethasone.ConclusionsThe review found moderate quality evidence that submucosal injections of dexamethasone reduced post-operative oedema and pain compared to a placebo following impacted third molar surgery. There was no significant difference, in regards to trismus, between placebo and dexamethasone.