This will be a split mouth study where 15 patients, (total 45 sites) will be included. Procedure will be explained to the patients attending outpatient section, Dept. of Periodontics, Coorg Institute of Dental Sciences, Virajpet and those willing voluntarily will be enrolled for the study. His/her written consent will be taken prior to commencement of the study.

INCLUSION CRITERIA:

1. Patient diagnosed with chronic periodontitis and good systemic health.

2. 30-55 years of age.

3. Untreated chronic periodontitis.

4. Patients  with  minimum  of  20  number  of  teeth  excluding  third  molar,   with   pocket

    depth ≥ 5mm.

5. Each of the three quadrants having one periodontal pocket.

EXCLUSION CRITERIA:

1. Patients   with   systemic   diseases   (e.g.,  diabetes  mellitus,   cancer,   human  immuno- 

    deficiency virus; bone-related diseases and collagen-metabolic diseases or disorders).

2. Pregnant and lactating women.

3. Smoking within the past 5 years.

4. Patients under certain drug therapies which effects bone metabolism.

5. Periapical pathologies.

6. Excessive forces including mechanical forces from orthodontics and occlusion.

7. Radiation or immunosuppressive therapy.

8. Patients who have undergone previous periodontal surgeries within the last 1 year.

9. Patients not willing for treatment.

Each individual will be categorized into three groups by random allocation of three quadrants of mouth.

(Group 1)  CONTROL:  Chronic periodontitis patients (sites having ≥ 5mm of probing pocket depth) treated by scaling and root planing alone.                   

(Group 2) TEST: Chronic periodontitis patients (sites having ≥ 5mm of probing pocket depth) treated by scaling and root planing and with LLLT therapy.

(Group 3) TEST: Chronic periodontitis patients (sites having ≥ 5mm of probing pocket depth) treated by scaling and root planing and with diode laser therapy.

Patients will be reviewed in series of four appointments (1, 7, 30 and 90^th day). At first visit all groups will undergo scaling and root planing. Group1 (control) will be on maintenance phase on 7^th and 30^th day.

Laser application procedure:

Diode laser therapy

The Periodontal pocket will be subjected to treatment with a diode laser operating at 810 nm wavelength (1W output power, continuous wave), equipped with a (300µ) optical fibre. Irradiation will be performed in contact mode, the fiber tip touching the pocket wall, to remove the pocket lining all around the teeth. To minimize gingival damage the tip will be moved at a constant speed of 1mm/sec.

Diode laser therapy will be performed on Group 3 (Test) on days 1 and 7 respectively after scaling and root planing procedure.

Low level laser therapy

Laser biostimulation (Low level laser therapy) will be done with a diode laser operating at 810 nm wavelength (0.1W output power, continuous wave), equipped with a (300µ) optical fibre. The fibre tip will be positioned in non-contact mode about 0.5 - 1mm away from periodontal pocket externally at right angles to long axis of tooth in a sweeping motion all over the area starting apically and moving upwards to coronal portion of pocket.

Low level laser therapy will be performed on Group 2 (Test) on days 1, 7 and 30 respectively after scaling and root planing procedure.

CLINICAL PARAMETERS TO BE ASSESSED ARE :

1. Gingival index (Loe & Sillness 1963)
2. Bleeding index (Muhlemann & son 1971)
3. Probing pocket depth (PPD) using UNC 15probe standardized by using customized acrylic stent.
4. Clinical attachment level (CAL) using UNC 15 probe standardized by using customized acrylic stent.

Clinical parameters will be assessed at baseline and on 90^th day for all the groups.

COLLECTION OF SAMPLES

In all the groups, three sites per individual will be selected for sampling. Site will be gently dried with air syringe and cotton rolls, samples of GCF will be obtained by placing calibrated volumetric microcapillary pipettes. From each site a standardized volume of 2 microliter will be collected. GCF sample will be collected from same site test group and control group at base line before treatment and on the 90th day for the assessment of osteoprotegerin concentration in GCF. Samples will be stored in 0.5 ml of 7.4 pH phosphate buffered saline solution.

BIOMARKER ANALYSIS

Concentration of osteoprotegerin in GCF will be determined using enzyme linked immunosorbant assay kit (ELISA) according to manufacturer’s directions.

STATISTICAL ANALYSIS :

All clinical and biochemical parameters will be subjected to appropriate statistical analysis by either parametric or non-parametric tests.