Quantification of Canine Dental Plaque Using Quantitative Light-Induced Fluorescence

Abstract

The aim of this work was to evaluate Quantitative Light-induced Fluorescence (QLF TM ) as an alternative to the established Logan and Boyce method for determining plaque coverage of dogs' teeth. In a series of studies in conscious and anesthetized dogs, QLF showed good intra-photographer repeatability (coefficient of variation [CV] of 7.5% for undisclosed teeth) and inter-photographer reproducibility (CV of 3.2% for undisclosed teeth and 8.5% for disclosed teeth). The QLF software accurately identifies areas of plaque as demonstrated by comparison to the variability of 5 human scorers, manually marking plaque on QLF-acquired images (P ¼ 0.1). There was good agreement with the modified Logan and Boyce method in the percentage reduction in plaque accumulation measured when dogs were fed an oral care chew versus no chew. To see a 15% difference in plaque accumulation, which is considered sufficient by the Veterinary Oral Health Council to differentiate between 2 treatments, a retrospective power analysis (90%) of the data established that only 7 dogs would be required, compared to 19 dogs for the modified Logan and Boyce method. QLF is a reliable method for measuring dental plaque in dogs with the added advantage that it is not subjective and requires fewer animals.

Prospective randomised blinded clinical trial assessing effectiveness of three dental plaque control methods in dogs

“…While beneficial in measuring plaque accumulation as defined as coverage of the tooth, one area in which QLF™ requires improvement is in the measurement of plaque depth, and Wallis et al . () advised this is an area that warrants further investigation.…”

“…Other methods such as quantitative light-induced fluorescence (QLF™), while more complex, have been shown to reduce subjectivity in the assessment of plaque accumulation, and can also reduce the sample size required to monitor plaque accumulation (Wallis et al 2016). While beneficial in measuring plaque accumulation as defined as coverage of the tooth, one area in which QLF™ requires improvement is in the measurement of plaque depth, and Wallis et al (2016) advised this is an area that warrants further investigation.…”

Comparison of dental plaque reduction after use of electric toothbrushes with and without QLF-D-applied plaque visualization: a 1-week randomized controlled trial

“…Quantitative light-induced fluorescence-digital (QLF-D)applied visualisation can be used to detect dental plaque on both human and animal teeth [1][2][3][4][5][6][7]. Red autofluorescence of dental plaque reflects endogenous porphyrins associated with products of microbiota metabolism [8,9]; the fluorescence of porphyrins corresponds to characteristic bands of absorbance between wavelengths of 390 nm and 425 nm, named Soret bands [10,11].…”

Comparison of dental plaque reduction after use of electric toothbrushes with and without QLF-D-applied plaque visualization: A 1-week randomized controlled trial

“…Quantitative light-induced fluorescence-digital (QLF-D)-applied visualisation can be used to detect dental plaque on both human and animal teeth [1][2][3][4][5][6][7]. Red auto-fluorescence of dental plaque reflects endogenous porphyrins associated with products of microbiota metabolism [8,9]; the fluorescence of porphyrins corresponds to characteristic bands of absorbance between wavelengths of 390 nm and 425 nm, named Soret bands [10,11].…”