An In Vitro Evaluation of the Effect of Sealant Characteristics on Laser Fluorescence for Caries Detection

Resident’s Name: Jessica Wilson

Program: Lutheran Medical Center - Providence

Article title: An In Vitro Evaluation of the Effect of Sealant Characteristics on Laser Fluorescence for Caries Detection.

Author(s): Gostanian et al.

Journal: Pediatric Dentistry

Year. Volume (number). Page #’s: 2006. 28(5). 445-450.

Major topic: Laser Fluorescence

Overview of method of research: Scientific Article

Background:
A previous study found that 82% of dentists who offer sealants did not place sealants over incipient or superficial lesions although literature suggests such properly sealed lesions arrested over time (became 89% inactive). If practitioners were able to “quantitatively monitor” caries progression under sealants they may be more open to sealant placement over these borderline lesions.

Purpose:
1. Assess ability of laser fluorescence (LF) to detect simulated caries under sealants
2. Determine effect of opacifying agent in various sealants on LF values
3. Determine interexaminer reproducibility values in lab setting

Methods:
2 unfilled and 1 filled sealant materials were used. Titanium dioxide powder was used as an opacifying agent and added to the 3 sealant materials. Discs of 0.5mm think sealants were prepared and placed over varying amounts of protoporphyrin IX, a material which mimics dental caries. A total of 270 LF readings were taken of the various discs.

Findings:
Readings from the LF were highly reproducible. Clear sealants which had no opacifying agents significantly depreciated LF readings. Filled sealants weakened LF readings significantly more than the unfilled sealants. The addition of titanium dioxide (opacifying agent) also attenuated LF values with concentrations approaching 0.5% being almost completely attenuated.

Key points/Summary:
-The use of LF to detect dental caries underneath sealants is not recommended due to unreliable readings as a result of attenuating signals by sealants and intrinsic fluorescence of the sealant material itself.
-Intrinsic fluorescence of a sealant may produce false positives.
-False negatives may be obtained due to scattering caused by filler.
-Previous studies conducted on human teeth found that sealants on permanent first molars did not affect DIAGNOdent values and that it was easy to detect caries under sealants.
-More studies should be done on human teeth with pre-existing caries.

Assessment of Article:
Although this study isolates several important characteristics of sealant materials, due to the fact that this was an in vitro study it limits it clinical application. Good groundwork article, but need more research.