Cariostatic effect of fluoride-containing restorative systems associated with dentifrices on root dentin.
OBJECTIVE
The aim of this in vitro study was to evaluate the interaction between two sources of fluoride (restorative systems and dentifrices) in inhibiting artificial root caries development.


METHODS
One hundred and eighty tooth segments were embedded in polyester resin, and sanded flat. Cylindrical cavities 1.0mm-deep and 1.5mm-diameter were prepared in root dentin and randomly restored by fluoride-containing restorative systems: Ketac-fil/Espe (Ke), Fuji II LC/GC Corp (Fj), F2000/3M (F2), Surefil/Dentsply (Su) or a control: Filtek Z250/3M (Z2). Ten experimental groups were made to test the association among the five restorative systems and two dentifrices: with F(-) (Sensodyne Baking Soda) or without F(-) (Sensodyne Original) (n=18). After surface polishing, a 1mm-wide margin around the restorations was demarcated and initial dentin surface Knoop microhardness values (KHN(i)) were obtained. The specimens were submitted to a pH-cycling model, and to applications of slurries of dentifrice. Afterwards the final dentin surface Knoop microhardness values (KHN(f)) were measured.


RESULTS
The differences between KHN(i) and KHN(f), and the covariate KHN(i) were considered by the ANCOVA and Tukey's test (alpha=0.05). The interaction between restorative system and dentifrice was statistically significant (p=0.0026). All restorative systems provided some protection against artificial caries challenge when associated with the fluoride-containing dentifrice treatment. The means (standard deviation) of reductions in Knoop hardness values for systems associated with the fluoride-containing dentifrice were: Ke: 40.0(1.02)(a), Fj: 41.9(1.02)(b), F2: 43.3(1.04)(c), Su: 43.5(1.00)(c), Z2: 44.0(1.02)(c); and with the non-fluoride-containing dentifrice were: Ke: 42.9(1.02)(a), Fj: 44.7(1.01)(b), F2: 45.2(1.09)(bc), Su: 46.0(0.99)(c), Z2: 46.6(0.99)(c) (statistical differences were expressed by different letters).


CONCLUSIONS
The cariostatic effect shown by the fluoride-containing dentifrice could enhance that shown by Ketac-fil and Fuji II LC, and could mask that shown by F2000.
Hara
Anderson Takeo
AT
Department of Restorative Dentistry, School of Dentistry of Piracicaba, University of Campinas (UNICAMP), SP, Brazil.
Magalhães
Cláudia Silami de
CS
Serra
Mônica Campos
MC
Rodrigues
Antonio Luiz
AL
D000704:Analysis of Variance; D002327:Cariostatic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D020770:Compomers / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry; D003764:Dental Materials / Q000737:chemistry*; D003775:Dental Polishing; D003793:Dental Restoration, Permanent; D003802:Dentifrices / Q000627:therapeutic use*; D003804:Dentin / Q000187:drug effects* / Q000648:ultrastructure; D004338:Drug Combinations; D005459:Fluorides / Q000008:administration & dosage / Q000737:chemistry / Q000627:therapeutic use*; D005899:Glass Ionomer Cements / Q000737:chemistry; D006244:Hardness; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008298:Maleates / Q000737:chemistry; D009566:Nitrates / Q000737:chemistry; D010710:Phosphates / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry; D012117:Resins, Synthetic / Q000737:chemistry; D017213:Root Caries / Q000517:prevention & control*; D013223:Statistics as Topic; D014092:Tooth Root / Q000187:drug effects* / Q000648:ultrastructure
D002327:Cariostatic Agents; D020770:Compomers; D003188:Composite Resins; D003764:Dental Materials; D003802:Dentifrices; D004338:Drug Combinations; C118368:F2000 cement; C444701:Filtek Z250; C079765:Fuji II LC cement; D005899:Glass Ionomer Cements; D008298:Maleates; D009566:Nitrates; D010710:Phosphates; D019279:Resin Cements; D012117:Resins, Synthetic; C097427:Sensodyne; C403464:SureFil packable composite; C040964:Ketac-Fil; D005459:Fluorides