Table 1. Characteristics of studies.
| Primary author (Year) Location Recruitment period | Study groups | Dental extraction | Surgical procedure | Randomization method | Collection of blood samples for culture | Antiseptic used | Most frequently identified bacteria | Regimens | Patients (%) with positive cultures | Bacteremia values selected for our meta-analysis * | Exclusions, withdrawals and losses | Adverse reactions |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rechmann[29](1989) Germany Not specified | CG (n = 16): NaCl solution-rinse group. EG (n = 17): chlorhexidine group | Only one tooth per patient (23 molars, 8 premolars and 2 front teeth) | All extractions were performed by the same person | Not specified | At baseline (before the start of surgery), 2 minutes and 10 minutes after the extraction | 0.1% chlorhexidine mouthwash | Streptococcus | CG: Rinsed the mouth with NaCl physiological saline solution for 2 minutes. EG: Rinsed the mouth with 0.1% chlorhexidine solution for 2 minutes. Patients received 100 ml of washing solution and were instructed to rinse intensely in the area | Overall:CG: 62.5%. EG: 82.4% | CG: 62.5%EG: 82.4%Values from positive cultures in at least one of the two time points (2 and 10 minutes after the extraction) in which blood samples are collected | - | Not recorded |
| Lockhart[28] (1996). USA. Not specified | CG (n = 33): placebo-rinse group. EG (n = 37): chlorhexidine group | A single-tooth extraction | The tooth was removed with forceps in the usual manner under local anesthesia. | By a random number generator in the hospital pharmacy | At 1 minute following the initiation of surgery and at the 3-minute mark | 0.2% chlorhexidine mouthwash | Streptococcus viridans group and alfa-hemolytic pyogenic streptococci | CG: Rinsed vigorously with 10 ml of placebo for 30 seconds and expectorated. Rinsing was repeated 1 min later. EG: Rinsed vigorously with 10 ml of 0.2% chlorhexidine hydrochloride for 30 seconds (after the patient was anesthetized) and expectorated. Rinsing was repeated 1 min later | Overall.:CG: 94% EG: 84% | CG: 94%EG: 84%Values from blood samples collected at either the 1-minute and/or 3-minute mark following the initiation of surgery | 12 patients were dropped:- 1 patient because of the loss of one of the two blood samples- 11 patients because of problems acquiring or maintaining an intravenous line | Not recorded |
| Tomás[27]. (2007). Spain. Not specified | CG (n = 53): Control group.EG (n = 53): Chlorhexidine group | The number of teeth to be extracted during the intervention depended on each patient | Dental extraction under general anesthesia (because of mental and behavioral disabilities) | Randomization was based on a single sequence of random assignments (simple randomization) created by applying a computer-generated randomization list. | At baseline (before performing the dental manipulation, but after endotracheal intubation), 30 seconds, 15 minutes, and 1 hour after the final dental extraction (after finishing the surgical procedure) | 0.2% chlorhexidine mouthwash | Streptococcus species, particularly viridans group streptococci | Control group: Received no chlorhexidine prophylaxis before the dental manipulation.Chlorhexidine group: Had their mouths filled with a 0.2% chlorhexidine digluconate solution for 30 seconds before the dental manipulation | At baseline: CG: 9%, EG: 8% At 30 seconds: CG: 96%, EG: 79% At 15 min: CG: 64%, EG: 30%At 1 hr:, CG: 20%, EG: 2% | CG: 96% EG: 79%Values from blood samples collected at 30 seconds after the extraction | 19 patients were excluded before randomization:- 12 due to the use of antibiotics in the 3 months before the study- 2 due to the use of oral antiseptics- 2 due to a disease that could predispose the patient to infections or bleeding | Not recorded |
| Tuna[10]. (2012). Turkey. Not specified | PI group (n = 12): Povidone iodine group. CHX group (n = 12): Chlorhexidine group. C Group (n = 10): Control group | An impacted mandibular third molar | With local anesthesia and under conditions considered aseptic. The third molars were exposed by elevating a buccal mucoperiosteal flap. Osteotomies were implemented by using handpieces under sterile saline irrigation | Patients were randomly allocated into three groups via drawing lots by the same blinded researcher | At baseline (preoperatively, before the injection of local anesthesia), 1 and 15 minutes after the completion of the extraction | 7.5% povidone iodine mouth rinse. 0.2% chlorhexidine mouth rinse | Streptococcus viridans; 38% were S. anginosus, 13% were S. salivarius and 13% S. mitis | Group 1: Rinsed the mouth with 15 ml 7.5% povidone iodine mouth rinse for 1 minute following the initial blood collection. Group 2: Rinsed the mouth with 15 ml 0.2% chlorhexidine mouth rinse for 1 minute following the blood collection. Group 3: Rinsed the mouth with 0.9% NaCl (sterile saline) solution | At 1 min: .CG: 40%, CHX group 25%, PI group 33%. At 15 min: . CG: 30%, CHX group 17%, PI group 0% | CG: 40% CHX group: 25%Values from blood samples collected at 1 minute after the extraction | 4 patients were excluded:- 2 from control group due to injury of the venous pathway during the insertion of the angiocath. - 2 from chlorhexidine group due to the presence of bacteremia discovered in the preoperative blood culture | Not recorded |
| Maharaj[26] (2012). South Africa Not specified | Group A (n = 40): Control group.Group B (n = 40): Chlorhexidine group .Group C (n = 40): Amoxicillin group.Group D (n = 40): Clindamycin group | Only one tooth | The same dental surgeon performed the procedure using dental forceps. No surgical procedures were used in any patient | Using a computer-generated randomization table | 8–10 ml of blood was drawn three minutes after the extraction in each patient | 0.2% chlorhexidine rinse | Viridans streptococci | Group A: No therapy prior to dental extraction.Group B: Rinsed their mouths vigorously with 10 ml of 0.2% chlorhexidine for one minute and expectorated, and this procedure was repeated one minute later. Group C: Took 3 g amoxicillin orally one hour prior to the dental extraction.Group D: Took 600 mg clindamycin orally one hour prior to the dental extraction. | Group A: 35%. Group B: 40%. Group C: 7.5%. Group D: 20% | Group A: 35%. Group B: 40%Values from blood samples collected at 3 minutes after the extraction | - | Not recorded |
| Duvall[11] (2013). USA. June 2011-December 2011 | CG (n = 10): Control group. CHX group (n = 10): Rinse group.AMOX group (n = 10): Antibiotic group | 4 third molars: tooth #1, tooth #32, tooth #16 and tooth #17 | Under conscious sedation and local anesthetic | Via a computer-generated model | At baseline, 1.5 min following initiation of the mucogingival flap #32, 1.5 min following initiation of the mucogingival flap #17, and 10 min following initiation of the mucogingival flap #17 | 0.12% chlorhexidine rinse | Viridans group streptococci | Control group: Placebo capsule 1 hour prior to the procedure + placebo rinse administered immediately prior to conscious sedation medication administration (15 ml for 1 min and expectorated). CHX group: Placebo capsule 1 hour to the procedure + 15 ml of chlorhexidine rinse for 1 min. AMOX group: 2 g amoxicillin 1 hour prior to the procedure + 15 ml of placebo rinse for 1 min | Overall:CG: 50%CHX group: 60%.AMOX group: 40% | CG: 50%. CHX group: 60%. Values from positive cultures at least one of the time points in which blood samples are collected | 7 subjects were not included in the study due to technical issues involving complications during blood draws and/or unavailable microbiological laboratory support | Not recorded |
| Ugwumba[25] (2014). Nigeria. November 2012 and June 2013 | CG (n = 42): Control group.Test group (n = 48): Chlorhexidine group | One or more molar teeth | Under local anesthesia using extraction forceps and/or an elevator | Using computer generated groups placed in white opaque envelopes | At baseline, 1 min and 15 min after the last tooth extraction | 0.2% chlorhexidine mouthwash | Staphylococcus aureus | CG group: sterile water mouthwash administered for 1 min before any dental manipulation. Test group: 0.2% chlorhexidine mouthwash administered for 1 min before any dental manipulation | Overall:CG group: 52.4%.Test group: 27.1% | CG: 33.3%Test group: 17%.Values from blood samples collected at 1 minute after the last tooth extraction | 11 subjects were excluded from the analysis of prevalence of bacteremia due to have positive baseline blood cultures (5 in control group and 6 in chlorhexidine group) | Not recorded |
| Barbosa[24] (2015). Portugal. 2010 and 2012 | CG (n = 52): Control groupCHX-MW group (n = 50): Chlorhexidine mouthwash group. CHX-MW/SUB_IR group (n = 51): Chlorhexidine mouthwash and subgingival irrigation. CHX-MW/SUPRA_IR group (n = 48): Chlorhexidine mouthwash and supragingival irrigation | A simple and single-tooth extraction | Under local anesthesia by the same calibrated clinician | Using the closed envelope technique | At baseline, 30 seconds after performing the mouthwash and the subgingival or supragingival irrigation, and at 30 seconds and 15 min after completion of the tooth extraction | 0.2% chlorhexidine mouthwash | Streptococci (particularly the S. viridans) | CG group: no prophylactic regimenCHX-MW group: performed a mouthwash with 0.2% chlorhexidine (10 ml for 1 min) before the tooth extraction. CHX-MW/SUB_IR group: performed a mouthwash with 0.2% chlorhexidine (10 ml for 1 min) + subgingival irrigation with 1% chlorhexidine (1.8 ml for 1 min) on the tooth to be extracted. CHX-MW/SUPRA_IR group: performed a mouthwash with 0.2% chlorhexidine (10 ml for 1 min) + supragingival irrigation with 1% chlorhexidine (10 ml for 1 min) on the tooth to be extracted | At 30 seconds after tooth extraction:. CG group: 52%CHX-MW group: 50%CHX-MW/SUB_IR group: 55%. CHX-MW/SUPRA_IR group: 50% | CG group: 52%.CHX-MW group: 50%Values from blood samples collected at 30 seconds after completion of the tooth extraction | 32 patients were excluded before randomization:- 20 due to not meeting inclusion criteria-12 due to declining to participateLost to follow-up = 5 patients:- 2 in the CHX-MW group- 3 in the CHX-MW/SUPRA_IR group | Not recorded |
* The bacteremia data selected to generate the database used in the meta-analysis were from blood samples collected within the first 10 minutes after the completion of the extraction or the initiation of surgery (according to the study design)
- Adverse reactions were not recorded in any study
- There were no split-mouth designs