Influence of antibiotic prophylaxis on the stability of orthodontic microimplants: A pilot randomized controlled...

The aims of this 2-arm parallel pilot randomized controlled trial were to investigate the influence of antibiotic prophylaxis on the stability of orthodontic microimplants and to evaluate the efficacy of systemic inflammatory marker measurements in detecting infections in tissues surrounding microscrews.

Orthodontic patients requiring en-masse distalization in the maxilla received antibiotics or a placebo before microimplant placement. Eligibility criteria included 13 years of age, and good general and oral health. Exclusion criteria comprised allergy to antibiotics, severe systemic allergy, heart and kidney diseases, and recent antibiotic treatment. Stability of the microimplants was the primary outcome; inflammation of the tissues surrounding the microscrews, pain related to the microimplantation, and serum levels of inflammatory markers were the secondary outcomes. Randomization in a 1:1 ratio was performed by auxilliary staff via a flip of a coin between 2 participants of the same sex and developmental stage, and the "winner" was allocated to the intervention group. Pharmaceutically prepared identical capsules with either amoxicillin (intervention) or glucose (control) given 1 hour before microimplant placement according to the allocation provided blinding of the participants. Subsequently, 1 clinician unaware of the allocation inserted the microimplants and assessed the outcomes, which simultaneously blinded the operator-assessor. Blood samples for laboratory analysis of inflammatory markers were collected a day before and 1, 3, and 7 days postoperatively.

Out of 80 participants initially assessed for eligibility, 41 received the randomized allocation. Three patients were lost to follow-up. Eventually, data of 18 and 20 participants (mean age, 20.4 ± 5.9 years) were available for analysis in the intervention and control groups, in which 1 and 2 patients lost a microimplant, respectively, resulting in odds ratio of 0.53 (95% confidence interval [CI], 0.0084-11.23; P = 1.0). The odds ratio for inflammation development was 1.22 (95% CI, 0.34-4.38), and the odds ratio for feeling milder pain was 1.174 (95% CI, 0.350-3.941) in the intervention compared with the control group, but the result was not statistically significant (P = 0.758; P = 0.795, respectively). The inflammatory marker levels did not increase due to either microimplantation (procalcitonin, P = 0.445; C-reactive protein, P = 0.4) or peri-implantitis. Antibiotic prophylaxis slightly decreased the levels of the biomarkers in the intervention group; however, the results were not statistically significant (P = 0.68; P = 0.908, respectively). No harms caused by the microimplantation procedure or drug intake were noted.

Antibiotics provided no benefit in terms of microimplant stability, inflammation of soft tissues, or postoperative pain in our pilot sample. Measurements of serum levels of inflammatory markers were inefficient in detecting soft tissue inflammations. These initial results should be interpreted with caution until validated by a large multicenter definitive trial.

This trial was not registered.

The protocol was not published before trial commencement.

The trial was funded by Wroclaw Medical University; grant number pbmn91 and supported by Diagnostyka.