EVALUATION OF THE USE OF ORTHODONTIC RECORDS TO MEASURE THE WIDTH OF KERATINIZED TISSUE

UNDERSTANDING THE GINGIVAL TISSUE response in patients undergoing orth odontic treatment requires accurate pretreatment measurements of the w idth of the attached and keratinized tissue. Even though these may not be routinely recorded, it has been suggested that the orthodontic rec ords can provide an accurate method of assessing the pretreatment kera tinized tissue width. This clinical study was conducted to compare mea sures of the width of the keratinized tissue calculated from intraoral photographs and study models with direct clinical measures. Maxillary and mandibular study models and intraoral photographs were obtained f rom 33 patients. The width of the keratinized gingiva facial to the ma ndibular incisors was measured on two occasions to the nearest 0.5 mm. The width of the gingiva was calculated for the same teeth from two m easures taken from projected photographic slides and the study models using a modification of Coatoam's technique. The method error was dete rmined to be 0.43 mm for clinical measures and 0.32 mm for the calcula ted gingival tissue width. The reliability of measurement from orthodo ntic records was slightly greater than direct clinical measurement, wi th intraclass correlations of 0.93 and 0.90, respectively. The differe nces between the averaged clinical measure and averaged calculated mea sure for each tooth were small and not statistically significant (pair ed t-test, P = 0.21, 0.66, 0.24, 0.24 for teeth 23 through 26 respecti vely). The results indicate that carefully taken photographic slides a nd study models can provide an accurate measure of keratinized tissue width.