The Response of Pathogens to the Respective or Combined Treatment of SRP and Local Minocycline in Chronic Periodontitis

The Response of Pathogens to the Respective or Combined Treatment of SRP and Local Minocycline in Chronic Periodontitis

The Response of Periodontal Pathogens to the Respective or Combined Treatment of Scaling and Root Planning and Locally Delivered Minocycline in Patients With Chronic Periodontitis- a Short-term Randomized Clinical Trial

To evaluate the respective or combinatory efficacy of locally delivered 2% Minocycline (MO) and surface and root planning (SRP) by assessing both clinical parameters and the loads of four main periodontal pathogens in treating chronic periodontitis.

In this randomized clinical trial, the investigators will evaluate the respective or combinatory efficacy of minocycline and scaling and root planning in the aspects of both clinical parameters [Pocket depth (PD) and sulcus bleeding index (SBI)] and the loads of four main periodontal pathogens [Aggregatibacter actinomycetemcomitans (Aa), Fusobacterium nucleatum (Fn), Porphyromonas gingivalis (Pg) and Prevotella intermedia (Pi)]. Real-time quantitative PCR (qRT-PCR) will be used as a powerful tool with high sensitivity and specificity to quantitatively assess target periodontal bacteria in a period of 7 days. The investigators will also try to correlate the reduction of either total or respective bacteria with the improvements of clinical parameters, with an aim to uncovering the potential microbiological mechanism accounting for the efficacy of a therapy.

Chronic periodontitis, Minocycline, Surface and root planning, Pocket depth, Sulcus bleeding index, Prevotella intermedia

surface and root planning is performed in a single-visit, one-stage, full mouth pattern using periodontal ultrasonic scaler (Satelec, Mérignac, France)

Locally delivered minocycline is administered directly into the periodontal pocket up to the gingival margin of the selected teeth

surface and root planning+locally delivered minocycline is the combined administration of both surface and root planning and locally delivered minocycline.

PD is measured using a standard CPI（community periodontal index） probe (Shanghai Medical Instruments, Shanghai, China) and assessed to the nearest millimeter.

BOP is evaluated for the treated tooth using the sulcus bleeding index (SBI) by Muhlemann with a range of 0 (no bleeding) to 5 (profuse bleeding)

Real-time quantitative PCR (qRT-PCR) was used as a powerful tool with high sensitivity and specificity to quantitatively assess target periodontal bacteria.

Inclusion Criteria: diagnosed with moderate or severe chronic periodontal disease, and exhibited bleeding on probing and attachment loss, with radiographic alveolar bone loss in four or more teeth Exclusion Criteria: pregnant, had used antibiotics within the last 3 months, had periodontal therapy in the past 6 months or had systemic diseases such as heart disease or hypertension