Overview Principles of QLF The Equipment The Results Clinical Uses Questions and Demonstration
Why a New Diagnostic Method? Prevent cavitation –Spotting trouble early early lesions (white spots) bacterial activity –Follow trouble through time –Objective support for the prevention process Enhance the quality of oral care –Improve the quality of restorations and sealants –Improve, encourage and focus the quality of oral hygiene
Early Lesion Detection ED Scattering properties of tooth tissue allow contrast enhancement White Spot
Red Fluorescence Detection ED
Pre-invasive Lesion Detection
QLF Contrast Enhancement White Light QLF
Examples of Bacterial Activity
The System and The Software PC Light guide Video camera QLF system box
Dentistry: QLF-Scan, QLF-Pro
Longitudinal Monitoring
Caries Mapping
Before brushing Area = 30.6 mm 2 ΔR = 51.8 % Red Fluorescence: Quantification R Cutoff = 20% clean After Brushing Area = 9.6 mm 2 ΔR = From 51.8% to 30.5 % White Spot Lesion Exposed
Danger Zones: Bacterial Activity Defective sealant.Sealant applied over unprepared carious tooth Red fluorescence indicating caries at the edges of a restoration. The restoration was replaced, yet secondary caries remains. SealantsRestorationsHidden Caries Discolored fissure in a molar identified as ‘sensitive’. Note the red hue around the fissure. When the fissure was opened, a dentinal lesion was found.
Use During Restorative Procedures Diagnose presence of secondary caries Check removal of bacterially affected tooth substance Red fluorescence indicating bacterially affected caries at the edges of a restoration. Corresponding radiograph: red arrows mark the radio- translucency underneath the restoration. The restoration was replaced, yet secondary caries remains. All pictures courtesy of Dr. R. Heinrich-Weltzien and Dr. J. Künisch, Friedrich-Schiller University of Jena, Erfurt, Germany
Area = 2.2 mm 2 ΔR = 32.4 % Area = 3.2 mm 2 ΔR = 47.5 % Area = 0.7 mm 2 ΔR = 25.3 % Red Fluorescence: Caries Excavation R Cutoff = 20% P. Sas 2003
Red Fluorescence: Sealants No RF Sound SealantLeaking Sealant R. Heinrich et al. 2001
Conclusions Agreement with visual inspection (Radike) –better sensitivity –very good specificity Quick patient assessment –Amount of initial lesions detected with QLF- Vision indicates caries risk Longitudinal monitoring of lesions –follow de- and remineralization in time QLF-Vision is a reliable method for early lesion monitoring
QLF ™ makes the invisible visible
Clinical Validation 1994 Øgaard and ten Bosch: demonstration of lesion tracking by measuring scattering properties 1995 de Josselin de Jong ea: Improvement of QLF system 1997 Al-Khateeb ea: detection of remin with QLF in weekly intervals consistent with microradiography 1998 Al-Khateen ea: QLF can be used to evaluate pre-invasive treatment 1998 Connersville study (IU): –QLF appropriate for use on occlusal as well as buccal-lingual surfaces –QLF is practical for large-scale clinical studies –QLF detects 4-9 times as many lesions vs. visual inspection –QLF validity for caries detection supported (ten Cate ea, 1999)
Clinical Validation 2001 Traneus ea: QLF is a sensitive method for longitudinal monitoring of incipient lesions on smooth surfaces Heinrich ea (to be published): QLF was able to separate groups of high-caries patients (33) that were given prophylaxis with or without the application of fluoride varnish, every 8 weeks for 6 months.
Clinical Validation in Progress At IUPUI (Dr. George Stookey): –2-Year study to validate QLF for the detection of primary caries –2-Year study to validate QLF for the detection of secondary caries –18-Month study of QLF to monitor caries in orthodontic patients –18-Month study of ability of QLF to detect differences in caries rates in patients provided toothpastes with different concentrations of fluoride At Inspektor: –Correlation between red fluorescence and specific bacterial strains. –Clinical study on bracket related incipient caries