Evaluation of the Controlled Release System of Doxycycline in Periodontal Therapy in Smokers With Chronic Periodontitis.

Summary The aim of this study is to evaluate through clinical, microbiological and immunological parameters using PLGA microspheres (lactic-co-glycolic acid polyacid) containing doxycycline in periodontal therapy in smokers with chronic periodontitis. For this study, 40 patients will be selected, with an average age between 30 and 59 years old of both genders (male and female), who spontaneously seek the clinic graduate of the Piracicaba Dental School -FOP / UNICAMP, and exhibiting at least four bleeding sites, including 2 sites with a probing depth (PD) between 5 and 6 mm and two sites PS ≥7 mm in uniradiculares teeth. Patients should have a minimum of 20 teeth. Will be excluded from relevant systemic disease carriers or antibiotics used in the 6 months preceding the study. All patients will receive oral hygiene instruction and will undergo a pre-treatment, which will be held supragingival sweeps and removal of plaque retentive factors. Patients will be divided into 2 groups (DB + DOX: Debridement + Doxycycline, test group and DB: only debridement, control group) of 20 patients who will receive the following treatments: periodontal debridement ultrasound for 45 minutes associated with the local administration of 1 mg microspheres containing doxycycline, or just mechanical debridement, for each selected site. Will be assessed the following clinical parameters: gingival index (GI) Plaque Index (PI), Bleeding on Probing (BOP), Position of the gingival margin (PGM), Probing Depth (PD) and Relative Clinical Attachment Level (RCAL). The microbiological evaluation will be made by means of polymerase chain reaction - real time ( "real time" - PCR) to detect bacteria: Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Aggregatibacter actinomycetemcomitans and Prevotella intermedia. The enzyme immunoassay (LUMINEXMAGPIX) allow the detection of cytokine levels of GM-CSF, INF-γ, IL-10, IL-12, IL-13, IL-1β, IL-4, IL-6, IL-8 and TNF-α. The analysis of the proteolytic enzyme activity is accomplished by using zymography to assess MMP-8 and MMP-9. The described parameters will be evaluated at baseline, 45 and 90 days after the initial visit. The results are compared statistically by analysis of variance with repeated measures with 5% significance level.