Comparative evaluation of two different systems of photometric analysis in the quantification of gingival color changes in patients undergoing scaling and root planing.

INTRODUCTION: Experimental gingivitis studies provided the first empiric evidence that the accumulation of microbial biofilm on clean tooth surfaces results in an inflammatory process in gingival tissues. Gingival and periodontal indices are used to assess the inflammatory changes in the gingiva and are considered the gold standard in the assessment of clinical outcomes. To the best of our knowledge, there are no direct indices to measure color changes in the gingiva.

AIM: To compare two different systems of digital photometric analysis (HSB color space and CIELab color space) to quantify gingival color changes in patients before and after scaling and root planing (SRP).

OBJECTIVES: To compare the color space values in the assessment of gingival color changes obtained using HSB and CIELab from digital photographs before and after scaling and root planing and to acertain the correlation if any, of gingival color changes quantified using photometric analysis with scores of other clinical indices used to assess the severity of gingival inflammation.

METHODOLOGY: The study will include patients of both genders in the age group of 20-60 years from the outpatient pool of the Department of Periodontics, KLE Society’s Institute of Dental Sciences, Banglore. A total sample of 75 individuals will be divided among 3 groups of 25 subjects each. All individuals taking part in the study will be recorded for clinical parameters i.e. Gingival index, Plaque index, Clinical attachment level, and Probing pocket depth along with standardized photographs of maxillary anterior sextant taken in triplicates (m1, m2, m3) by the same operator at baseline and 3 months followup. Individuals belonging to Group 1 and Group 2 will undergo routine SRP with hand and ultrasonic instruments at baseline 6 weeks and 12 weeks. The photographs will be taken with a Nikon L280 digital camera with a ring flash. The specifications will be kept at ISO 125, shutter speed 1/200, aperture F20, white balance, and 8% grey scale. The camera will be placed at a fixed distance from the patient’s oral cavity using a tripod. Chee retractors will be used for better visualization. A disc will be cut from a sheet of red articulating paper. The disc will have almost identical red pixel values when checked before use. It will be attached using the patient’s saliva to the upper left lateral incisors to facilitate standardization. Calibration and analysis of the images for quantification of gingival color will be done using color space converter software. A routine at the region of interest will be marked on the digital photograph. The image will be split into different images based on the coordinates present in CIELab and HSB color space respectively. In all the images that will be taken in triplicates (m1, m2, m3) three fixed points in the XY axis will be selected and the values will be recorded for all coordinates in both CIELab and HSB color space.