Do Antibiotics Decrease the Risk of Inflammatory Complications after Third Molar Removal in Community Practices?

Purpose:

The role of antibiotic use in third molar (M3) surgery is unclear and remains controversial.  A 2013 Cochrane review found evidence indicating antibiotic use reduced the risk of surgical site infection (SSI) and alveolar osteitis (AO) following extraction of M3s.^[1]  The purpose of this study was estimate the frequency of antibiotic use in M3 surgery, the frequency of postoperative inflammatory complications following M3 surgery, and to measure association between antibiotic use and postoperative inflammatory complications following M3 surgery in the community, office-based ambulatory practice setting.

Materials and Methods:

Study design:  The investigators designed and implemented a prospective cohort study and enrolled a sample of subjects derived from the population of patients who had M3s removed in the private practice setting in the US between June, 2011 and May, 2012 using a practice-based research collaborative.^[2]

Study variables:  The predictor variable was antibiotic use of any type categorized as yes or no.  The primary outcome variable was the presence or absence of an inflammatory complication, i.e. SSI or AO, after M3 removal.  A diagnosis of AO was made based on history and exam with history of new onset or increasing pain > 36 hours after the operation and exam showing loss of the blood clot with exposed bone, irrigation of the site or gentle probing reproducing the pain, and significant pain relief with application of an anodyne dressing.  A diagnosis of surgical site infection was made based on visible frank purulence of the extraction site at any point postoperatively or unanticipated pain or edema warranting operative intervention or antibiotic use.  The other study variables were grouped into the following categories: demographic (sex and age), risk factor variables (ASA class, tobacco use, alcohol use, medications and chronic conditions), M3 factors (preoperative disease around the M3), and treatment variables (number of M3s removed, operative difficulty, intraoperative complications, and other chemotherapeutic (chlorhexadine) use).   

Methods of Data Analysis:

Descriptive and bivariate statistics were computed to measure the association between antibiotic use and inflammatory complications after M3 removal with statistical significance set at ≤0.05.

Results/Outcomes Data:       

The study sample was composed of 2954 subjects who had at least one M3 removed.  The sample's mean age was 26.4 (±13.5) and 47.5% were males.  Three-quarters (76%) of the sample received antibiotics in some form. The overall inflammatory complication (AO/SSI) frequencies in the antibiotic and non-antibiotic groups were 5.0% and 7.6%, respectively (p=0.008).The frequency of AO in the antibiotic and non-antibiotic groups were 4.4% and 6.4% respectively (p=0.04). The frequencies of SSI in the antibiotic and non-antibiotic groups were 0.7% and 1.4% respectively (p=0.08).   The patterns of antibiotic use, e.g. type, dose, timing, and route of delivery, were too numerous to identify an optimal antibiotic strategy.  

Conclusions:

The results of this study suggest that antibiotic therapy, regardless of type, dose, frequency, or pattern of delivery, was associated with a decreased risk of inflammatory complications after M3 removal.

References:

1. Lodi G, Figini L, Sardella A, Carrassi A, Del Fabbro M, Furness S.  Antibiotics to Prevent Complications Following Tooth Extractions (Review).  Cochrane Database Syst Rev.  2013. 

2. Dodson, TB.  2011-2012 AAOMS Anesthesia-third molar outcome study.  I Anesthesia and Third Molar Extraction Benchmark Statistics, 2012 Annual Meeting of the American Association of Oral and Maxillofacial Surgeons, San Diego, CA.

Disclosure:  This study was supported in part by the AAOMS Anesthesia and Third Molar Extraction Outcome Studies (PI – T. B. Dodson) and the University of Washington Department of OMS Research and Training Fund.