Reliability of Different Techniques for Assessing Silver Nitrate-Treated Lesions

Objectives: Objective: Silver nitrate has received much recent attention as a means of treating early childhood caries by arresting carious lesions. However, there is no standard means to assess whether lesions are arrested. The purpose of this in vitro study was to assess the reliability of different probes on both untreated and silver nitrate-treated carious lesions.
Methods: Methods: One hundred and twenty extracted teeth were selected to represent a variety of carious lesions. They were then randomly divided into two groups: silver nitrate and control. Each of these groups was further divided into three sub-groups for each of the probes tested: standard periodontal probe, WHO ball ended probe, and shepherds hook explorer. Using a small applicator, silver nitrate was applied several times to each lesion, allowing the lesions to air dry between applications. All lesions were probed by an experienced examiner and a 4^th year dental student and scored on a 0 (hard), 1 (soft), 2 (very soft & leathery) scale. Inter-examiner and intra-examiner reliability was assessed for each type of probe using the kappa statistic. Only lesions treated with silver nitrate are reported here.
Results: Results: For inter-examiner reliability, kappa scores were (first assessment, second assessment): .545 and .547 for the periodontal probe, .615 and .251 for the ball ended probe and .431 and .677 for the explorer. For intra-examiner reliability, the kappa scores were (examiner 1, examiner 2) .704 and .689 for the periodontal probe, .455 and .478 for the ball ended probe, and .500 and .518 for the explorer.
Conclusions: Conclusions: Results from this in vitro study suggest that use of the periodontal probe produces best combination of inter and intra- examiner reliability; however in vivo studies are needed.