Objectives: Almost complete infiltration of enamel caries with light curing resins (infiltrants) has been shown in vitro for lesions scored as ICDAS-II code 2. The aim of the present study was to evaluate the penetration depths of an infiltrant into natural lesions varying in ICDAS-II scores. Methods: Eighty-four extracted human teeth showing proximal caries lesions (ICDAS-II code: 2, 3, 4, and 5) were positioned in silicone adjacent to a sound neighboring tooth mimicking the clinical situation. Proximal surfaces were etched with 15% hydrochloric acid gel for 2 min, dried after application of ethanol, and infiltrated twice (3 min and 1 min). Etching and infiltration steps were performed using a perforated double foil applicator (Icon; DMG, Hamburg, Germany). After removing surplus using floss, the infiltrant was light cured. Ground sections were prepared for analysis of lesion depth (maximum distance from surface to bottom of lesion), percentage of resin infiltrated in relation to demineralized lesion areas (%Inf.demin.) within enamel, percentage of cavitation filled with infiltrant (%Inf.cavit.) and percentage of infiltrant in demineralized plus cavitated lesion parts (%Inf.all) using confocal microscopy. Results: Median maximum lesion depths (25th;75th percentile) of lesions (maximum lesion depth ≥500 µm; n=73) were 963 (766; 1290) µm.
ICDAS | Cavitation | n | median(25th;75th percentile) | |||
Lesion depth* | %Inf. demin. # | %Inf. cavit.* | %Inf. all* | |||
2 | no | 16 | 897(706;1109) | 73(39;97)BC | n/a | 73(39;97) |
3 | no | 9 | 1251(729;1325) | 84(40;98)ABC | n/a | 84(40;98) |
yes | 12 | 954(742;1197) | 87(64;98)AB | 0(0;17) | 73(56;87) | |
4 | no | 7 | 943(835;1156) | 34(22;75)C | n/a | 34(22;75) |
yes | 12 | 973(655;1524) | 87(60;100)AB | 5(0;64) | 52(40;72) | |
5 | yes | 17 | 1154(911;1424) | 100(75;100)A | 0(0;30) | 43(22;64) |
*No significant differences (Kruskal-Wallis p>0.05), #significant differences (Mann-Whitney; p<0.05) between groups within columns highlighted with superscript letters.
Conclusion: Most demineralized parts of caries lesions rated as code 2 and 3 (ICDAS-II) can be infiltrated, whereas cavitated parts could not be filled with the infiltrant.
Supported by the Deutsche Forschungsgemeinschaft (PA 1508/1-2). HML and SP receive a research grant and royalties from DMG, Hamburg.