Comparison of Azithromycin and Amoxicillin Before Dental Implant Placement: An Exploratory Study of Bioavailability and Resolution of Postoperative Inflammation

BACKGROUND: Studies suggest that a single prophylactic dose of amoxicillin reduces early implant complications, but it is unclear whether other antibiotics are also effective. This study compared the local antimicrobial and anti-inflammatory effects resulting from a single dose of azithromycin or amoxicillin prior to surgical placement of one-stage dental implants. METHODS: Healthy adult patients requiring one-stage dental implant placement were randomly allocated to receive either 2g amoxicillin (n=7) or 500mg azithromycin (n=6) prior to surgery. Peri-implant crevicular fluid (PICF) samples from the new implant and gingival crevicular fluid (GCF) from adjacent teeth were sampled on postoperative days 6, 13 and 20. Inflammatory mediators in the samples were analyzed by immunoassay and antibiotic levels were measured by bioassay. RESULTS: On day 6, azithromycin concentrations in GCF and PICF were 3.39±0.73μg/ml and 2.77±0.90μg/ml, respectively, while amoxicillin was below the limit of detection. During early healing, patents in the azithromycin group exhibited a significantly greater decrease in GCF volume (p=0.03, ANOVA). At specific times during healing, the azithromycin group exhibited significantly lower levels of IL-6 and IL-8 in GCF than the amoxicillin group and exhibited significantly lower levels of G-CSF, IL-8, MIP-1β and IP-10 in PICF. CONCLUSIONS: Azithromycin was available at the surgical site for a longer period of time than amoxicillin, and patients taking azithromycin exhibited lower levels of specific pro-inflammatory cytokines and chemokines in GCF and PICF. Thus, preoperative azithromycin may enhance resolution of postoperative inflammation to a greater extent than amoxicillin

In vitro incidence of root canal bifurcation in mandibular incisors by radiovisiography

OBJECTIVE: The aim of this study was to verify, in vivo and in vitro, the prevalence of root canal bifurcation in mandibular incisors by digital radiography. MATERIAL AND METHODS: Four hundred teeth were analyzed for the in vivo study. Digital radiographs were taken in an orthoradial direction from the mandibular incisor and canine regions. The digital radiographs of the canine region allowed visualizing the incisors in a distoradial direction using 20º deviation. All individuals agreed to participate by signing an informed consent form. The in vitro study was conducted on 200 mandibular incisors positioned on a model, simulating the mandibular dental arch. Digital radiographs were taken from the mandibular incisors in both buccolingual and mesiodistal directions. RESULTS: The digital radiography showed presence of bifurcation in 20% of teeth evaluated in vitro in the mesiodistal direction. In the buccolingual direction, 17.5% of teeth evaluated in vivo and 15% evaluated in vitro presented bifurcation or characteristics indicating bifurcation. CONCLUSIONS: Digital radiography associated with X-ray beam distally allowed detection of a larger number of cases of bifurcated root canals or characteristics of bifurcation