In vitro model for evaluating the effect of child formula toothpastes on artificial caries in primary dentition enamel.
OBJECTIVE
To determine if the in vitro 10-day pH-cycling model used for permanent teeth could be utilized to evaluate de/remineralization effects, on the enamel of primary teeth, of child formula toothpastes.


METHODS
Sound extracted primary anterior teeth were coated with nail varnish, leaving a 1 mm-wide window prior to being placed in a demineralizing solution to produce artificial carious lesions in enamel. The teeth were subsequently cut longitudinally into 100 microm thick sections. The 72 specimens were randomly assigned to six groups. In Set 1 contained the specimens in Group a, which were treated with a pea-sized (0.32 g) quantity of non-fluoride toothpaste (First Teeth), and Groups b and c which were treated with half and pea-sized (0.16 g) quantities of fluoridated toothpaste (Colgate), and cycled for 10 days. The specimens in Set 2 (Groups A, B and C) were similarly treated but subjected to 7-day pH-cycling.


RESULTS
After Day 8 the lesions in Set 1 extended into dentin and so could not be evaluated. Polarized light microscopy and microradiography were used to evaluate the lesions subjected to 7-day pH-cycling. Lesions in Groups A and B increased in depth and area by approximately 50%, while those in Group C increased in depth and area by 20%; however, no statistically significant differences occurred between the groups. If this model pH cycling is to be used for primary teeth, a reduction from 10 to 7 days in length should be considered.
Thaveesangpanich
Puckpring
P
Paediatric Dentistry and Orthodontics, Faculty of Dentistry, The University of Hong Kong, Prince Philip Dental Hospital, 34 Hospital Road, Hong Kong SAR, PR China.
Itthagarun
Anut
A
King
Nigel M
NM
Wefel
James S
JS
Tay
Franklin R
FR
D002327:Cariostatic Agents / Q000008:administration & dosage*; D002675:Child, Preschool; D003731:Dental Caries / Q000628:therapy*; D003743:Dental Enamel / Q000473:pathology; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007180:Incisor; D008962:Models, Theoretical; D011897:Random Allocation; D012969:Sodium Fluoride / Q000008:administration & dosage*; D013997:Time Factors; D014089:Tooth Remineralization / Q000379:methods; D014094:Tooth, Deciduous; D014100:Toothpastes / Q000737:chemistry* / Q000627:therapeutic use*
D002327:Cariostatic Agents; D014100:Toothpastes; D012969:Sodium Fluoride