Some beneficial effect on root caries from use of higher concentration fluoride toothpaste (5000 ppm F)

Single-blind, multi-centre, parallel, randomised controlled trial. Intervention Adult patients (18-75 years) with 10 or more natural teeth, and one or more root caries lesion in a tooth not crowned or compromised were included. Patients were randomised to receive a high fluoride toothpaste, 1.1% sodium fluoride (5000 ppm F) or a regular toothpaste (1350 ppm F). Packaging was identical and standard brushes were also provided. Patients were strictly instructed to refrain from using toothpastes or toothbrushes other than the ones provided and restricted from using mouth rinses.

The primary outcome measure was changes in the surface structure of the root caries lesions after the intervention. This was graded using a surface hardness score (HS) scale: Level 1: hard; Level 2: hard to leathery; Level 3: leathery; Level 4: leathery with local softening; Level 5: soft. Scores were recorded at baseline, three and six months. Examiners were masked to the group assignment.

One hundred and thirty-five patients (test group: n = 67; control group: n = 68) with 318 identified root caries lesions were randomised. Five patients were lost to follow up, three in the test group and two in the control. The groups were similar at baseline. Overall there was no difference between the two groups for the overall HS (test group: HS = 3.4 ± 0.61; control group: HS = 3.4 ± 0.66; P = 0.8757, unpaired t-test). However the ANOVA revealed significantly better HS for the test group than for the control groups (T1: test group: HS = 2.9 ± 0.67; control group: HS = 3.1 ± 0.75; T2: test group: HS = 2.4 ± 0.81; control group: HS = 2.8 ± 0.79; P < 0.0001).

The application of a high-fluoride containing dentifrice (5000 ppm F) in adults, twice daily, significantly improves the surface hardness of otherwise untreated root caries lesions when compared with the use of regular fluoride containing (1350 ppm F) toothpastes.

The authors' institutions received per capita remunerations and the products used in this clinical trial, from Colgate-Palmolive Company. Roger P. Ellwood and Michael Warncke are employees of the Colgate-Palmolive Company.