Diagnostic characteristics of clinical and microbiological tests for monitoring periodontal and peri-implant mucosal tissue conditions during supportive periodontal therapy (SPT)

The aim of this study was to evaluate a clinical and a microbiological test for monitoring tissue condition during supportive periodontal therapy (SPT ) and to compare their diagnostic characteristics at implant and tooth site s. Twelve female (age: 37-72 years) and 7 male patients (age: 26-83 years) were evaluated in this study on the basis of availability to follow a rigid SPT program. Patients had received a complete periodontal examination at 1 and 5 years after implant placement. This included standardized radiograph s obtained at implants and matching control teeth. One implant site and one tooth site per patient were followed during the last 2 years of the SPT pr ogram. At each recall visit microbiological samples were analyzed according to DNA/RNA analysis identifying periodontal pathogens (IAI Pado Test 4.5(R ), Institute for Applied Immunology, Zuchwil, Switzerland). Presence or abs ence of bleeding on probing at these sites was also noted using a standardi zed probing force of 0.25 N (Audio Probe(R), ESRO, Thalwil ZH, Switzerland) . The percentage number of recall visits with positive bacteriological test results and positive BOP scores were calculated. Disease progression at th e sites was defined if the annual increase in probing depth was greater tha n or equal to0.5 mm/year (2.5 mm in 5 years) or if the annual decrease in C ADIA values (Computer Assisted Densitometric Image Analysis) was more than -0.7 per year (-3.5 in 5 years). Changes below these values were considered as negative test results indicating stability of the sites. The diagnostic characteristics (sensitivity, specificity, positive and negative predictiv e values) of BOP and microbiological tests alone or in combination were the n calculated using two-by-two tables. By application of increasing threshol ds of BOP frequencies set for definition of positive test outcome (BOP grea ter than or equal to 10% greater than or equal to 20% greater than or equal to 25% greater than or equal to 50% greater than or equal to 75% greater t han or equal to 90% or the combined BOP greater than or equal to 75%, but D NA positive greater than or equal to 10%, greater than or equal to 25% grea ter than or equal to 34% greater than or equal to 50% greater than or equal to 67% greater than or equal to 90%) receiver operator characteristics cur ves (ROC) were constructed for teeth and implants. The areas under the ROC curves were calculated and compared by means of chi-square tests. The resul ts indicated statistically significant better diagnostic characteristics of both tests at implants compared to teeth. The inclusion of an additional m icrobiological test significantly enhanced the diagnostic characteristics o f BOP alone at teeth as well as at implants.