Schmidt EF. Bretz WA. Hutchinson RA. Loesche WJ. Correlation of the hydrolysis of benzoyl-arginine naphthylamide (BANA) by plaque with clinical parameters and subgingival levels of spirochetes in periodontal patients. Journal of Dental Research. 67(12):1505-9, 1988 Dec.
Recent studies have shown that the extent of hydrolysis by plaque of
the trypsin substrate, N-benzoyl-DL-arginine-2-naphthylamide (BANA), correlates
with the numbers and proportions of spirochetes in subgingival plaque samples,
and appears to be an indicator of clinical disease. In this study, BANA
hydrolysis by subgingival plaque was evaluated in a blind manner for its
ability to reflect both clinical parameters and subgingival levels of bacteria
and spirochetes. Subgingival plaque samples were collected from periodontally
healthy and diseased sites in 23 untreated periodontal patients and in 13
treated and maintained periodontal patients. In untreated patients, BANA
hydrolysis was statistically associated with the total number of spirochetes
and bacteria in the plaque sample, but in the treated patients BANA hydrolysis
was statistically associated only with the spirochetes. Most BANA-positive
reactions in both patient groups were from the sites which were clinically
diseased and high in spirochetes. The majority of the negative reactions
for BANA hydrolysis in both patient groups was among the sites which were
periodontally healthy and low in spirochetes. Specificity and sensitivity
of the test were above 80% for disease status in untreated patients. The
predictive value of a positive and negative test was above 83%. Slightly
lower sensitivity, specificity, and predictive values were found in the
treated group. The BANA reaction appears to be an accurate and simple indicator
of both clinical disease status and plaque levels of spirochetes in individual
tooth sites in untreated and treated periodontal patients.