THE EFFECTS OF INCUBATION LENGTH AND TEMPERATURE ON THE SPECIFICITY AND SENSITIVITY OF THE BANA (N-BENZOYL-DL-ARGININE-NAPHTHYLAMIDE) TEST

A PREVIOUS MULTI-CENTER STUDY EXAMINING patients diagnosed as having at least four periodontally diseased teeth showed that when BANA (N-Benzoyl-DL-Arginine-Naphthylamide) hydrolysis by periodontal pathogens such as Treponema denticola, Porphyromonas gingivalis, and Bacteroides forsythus was evaluated versus clinical parameters such as clinical judgment of disease, bleeding on probing, and pocket depth, the sensitivity of the test was 84%, 82%, and 87%, respectively, while the specificity was only 42%, 41%, and 32%, respectively. The purpose of the present investigation was to improve the specificity of the test while retaining a high level of sensitivity in both gingivally healthy and periodontally diseased groups. One hundred forty-nine patients participated in this study providing 3,497 interproximal plaque samples. Gingival health was measured using the papillary bleeding score and this was compared with the presence or absence of detectable trypsin-like activity, as determined by the BANA hydrolysis of interproximal plaque samples, using a commercially-available test. Sensitivity and specificity were measured by varying the incubation time and temperature of the enzymatic assay. Using the correlated binomial model to analyze site-specific data within a patient, the specificity was highest at 35-degrees-C and 5 minutes incubation (94%), and lowest at 45-degrees-C and 15 minutes incubation (33%). Sensitivity was highest at 45-degrees-C or 55-degrees-C and 15 minutes incubation (90%) and lowest at 35-degrees-C and 5 minutes incubation (47%). When the sensitivity and specificity of the test run at 35-degrees-C for 5 minutes were used in a model for a diagnostic test proposed by Douglass and Fox, the test has utility when used on older general dental patients and for periodontal patients.