Remineralisation study of artificial root caries lesions after fluoride treatment. An in vitro study using electric caries monitor and transversal micro-radiography.
OBJECTIVE
To evaluate and compare remineralisation of root caries lesions after in vitro treatment with various fluoride (F) agents using an Electric Caries Monitor (ECM) and Transversal Micro-Radiography (TMR).


METHODS
Permanent human teeth were extracted and root surface specimens were sectioned, prepared (n = 35), and randomly allocated into seven different experimental groups (groups 1-7).


METHODS
Root surfaces were demineralised in an acidified gel (pH = 5.0) for 3 weeks followed by various F treatments and stored in a standardised remineralising solution at 37 degrees C for 6 weeks. The root surfaces were treated twice daily with different dentifrice slurries for 2 min, either with a neutral placebo dentifrice without F (group 5); or a neutral sodium fluoride (NaF) 1400 p.p.m. F dentifrice (group 1); or a neutral 1250 p.p.m. F dentifrice (group 6); or an acid dentifrice (pH 4.7) with 1400 p.p.m. F containing amine fluoride (AmF) (groups 3 and 4) or a 1250 p.p.m. (pH 4.7) AmF dentifrice (group 6). In groups 1, 2, 5, 6, and 7, the root surfaces were additionally rinsed for 2 min with a neutral non-F placebo solution. In groups 3 and 4, rinsing were performed for 2 min with an acid (pH 4.7) 250 p.p.m. F solution, containing 125 p.p.m. F as AmF and 125 p.p.m. F as potassium fluoride (KF), once or twice per day respectively. ECM was used to measure electrical resistance on root surfaces at baseline and after 3 and 6 weeks respectively. TMR technique was used to measure and compare root surface lesion depths and mineral loss.


RESULTS
Six weeks daily treatment with a dentifrice slurry containing AmF followed by rinsing with a combination of equal amounts of AmF and KF solution twice a day showed a statistical significant higher ECM values compared with the other groups. TMR data measuring lesion depths and mineral loss reduction supported the results of the ECM findings.


CONCLUSIONS
Daily application of a dentifrice slurry containing 1400 p.p.m. F as AmF combined with twice daily rinsing with a 250 p.p.m. F solution containing equal amount of AmF and KF significantly remineralise primary root caries lesions in vitro. ECM and TMR are valuable complementary methods in order to analyse the remineralisation processes.
Petersson
Lars G
LG
Department of Community and Preventive Dentistry, Maxillofacial Unit, Central Hospital, Halmstad, Sweden. lars.g.petersson@lthalland.se
Kambara
Masaki
M
D000588:Amines / Q000008:administration & dosage; D002327:Cariostatic Agents / Q000008:administration & dosage*; D003732:Dental Caries Activity Tests / Q000379:methods*; D003802:Dentifrices; D003959:Diamines; D005459:Fluorides / Q000008:administration & dosage*; D006801:Humans; D008852:Microradiography; D017680:Potassium Compounds / Q000008:administration & dosage; D017213:Root Caries / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D012969:Sodium Fluoride / Q000008:administration & dosage; D014089:Tooth Remineralization / Q000379:methods*
D000588:Amines; D002327:Cariostatic Agents; D003802:Dentifrices; D003959:Diamines; D017680:Potassium Compounds; C495399:Olaflur; D012969:Sodium Fluoride; C033320:potassium fluoride; D005459:Fluorides