title: Cross-sectional microhardness of bovine enamel subjected to three paediatric liquid oral medicines: an in vitro study.
abstract: OBJECTIVE
  This study aimed to investigate the in vitro effects of three paediatric liquid oral medicines on bovine dental enamel subsurfaces under pH cycling conditions.
  
  
  METHODS
  Bovine enamel blocks were evaluated for surface hardness at baseline for sample selection. 52 intact bovine enamel blocks (16mm(2)) were randomly divided into four groups (n=13) according to the immersion treatments: G1: antibiotic (Klaricid®), G2: antihistamine (Claritin®), G3: antihistamine (Dimetapp®) and G4: control (de-ionised water). The blocks were submitted to pH cycling treatments twice a day for 12 days. The medicines were evaluated for pH, viscosity, and concentration of calcium, phosphate and fluoride. After the treatment period, cross-sectional microhardness (CSMH) measurements of the enamel blocks were taken and the data, expressed in Knoop hardness number (kg/mm(2)) was used to calculate the ΔS.
  
  
  METHODS
  ANOVA followed by the Tukey test were used for statistical analyses (p<0.05).
  
  
  RESULTS
  The antibiotic Klaricid® showed the highest concentration of fluoride, calcium and phosphate. Considering pH and viscosity, the following pattern was observed according to the treatment group: G4>G1>G2>G3 and G1>G2>G3>G4 respectively. Regarding the demineralisation pattern, the following results were observed: G4>G3>G2>G1. Compared to the control, the antibiotic and both the antihistamines provoked less demineralisation of the enamel blocks (p<0.05).
  
  
  CONCLUSIONS
  Antibiotic G1 (Klaricid®) presented an in vitro protective effect against acid attacks probably due to its mineral content and viscosity.
authors.affiliation: Federal University of Rio de Janeiro, Rio de Janeiro, Brazil. rorefa@terra.com.br
authors.forename: D N
authors.initials: DN
authors.lastname: Soares
authors.forename: A C
authors.initials: AC
authors.lastname: Valinoti
authors.forename: V S S
authors.initials: VS
authors.lastname: Pierro
authors.forename: A G
authors.initials: AG
authors.lastname: Antonio
authors.forename: L C
authors.initials: LC
authors.lastname: Maia
mesh_terms: D019412:Anatomy, Cross-Sectional; D000818:Animals; D000900:Anti-Bacterial Agents / Q000009:adverse effects / Q000737:chemistry; D001977:Brompheniramine / Q000009:adverse effects / Q000737:chemistry; D002118:Calcium / Q000032:analysis; D002417:Cattle; D017291:Clarithromycin / Q000009:adverse effects / Q000737:chemistry; D003743:Dental Enamel / Q000187:drug effects*; D003747:Dental Enamel Solubility / Q000187:drug effects; D004338:Drug Combinations; D005459:Fluorides / Q000032:analysis; D006244:Hardness; D039563:Histamine H1 Antagonists, Non-Sedating / Q000009:adverse effects / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D017336:Loratadine / Q000009:adverse effects / Q000737:chemistry; D014663:Nasal Decongestants / Q000009:adverse effects / Q000737:chemistry; D010592:Pharmaceutic Aids / Q000009:adverse effects* / Q000737:chemistry; D010710:Phosphates / Q000032:analysis; D054199:Pseudoephedrine / Q000009:adverse effects / Q000737:chemistry; D011897:Random Allocation; D012996:Solutions; D017001:Tooth Demineralization / Q000139:chemically induced; D014783:Viscosity
chemical_list: D000900:Anti-Bacterial Agents; D004338:Drug Combinations; D039563:Histamine H1 Antagonists, Non-Sedating; D014663:Nasal Decongestants; D010592:Pharmaceutic Aids; D010710:Phosphates; D012996:Solutions; C007484:brompheniramine, pseudoephedrine drug combination; D017336:Loratadine; D054199:Pseudoephedrine; D017291:Clarithromycin; D001977:Brompheniramine; D005459:Fluorides; D002118:Calcium