title: A Randomized Clinical Study to Evaluate the Effect of Two Experimental Toothpastes on Tooth Enamel Gloss and Smoothness.
abstract: OBJECTIVE
  The study compared the effects on examiner-assessed tooth gloss and smoothness of two experimental toothpastes (1% or 2% alumina abrasive) with a reference, silica-based toothpaste used twice daily for one, four, and eight weeks. The study also monitored the safety of the products.
  
  
  METHODS
  This was a randomized, examiner-blind study, stratified by gloss score and age, three-treatment, parallel-group using healthy adult volunteers. Following a two-week washout period where subjects brushed with a conventional silica-abrasive toothpaste, 169 subjects began the trial period after receiving a dental scaling and polishing using the washout toothpaste. Subjects brushed for two minutes, twice daily, with their assigned toothpaste. The experimental toothpastes contained 927 ppm fluoride as NaF with either 1% or 2% alumina as the sole abrasive. The reference toothpaste contained 927 ppm fluoride as NaF in a conventional amorphous silica abrasive base. Enamel polish (i.e., gloss) was assessed visually by comparing the facial surfaces of the maxillary incisors with a set of standards. Tooth smoothness was assessed by lightly dragging a dental explorer over the surface.
  
  
  RESULTS
  Subjects using the 2% alumina toothpaste had significantly higher gloss compared to the reference toothpaste at Weeks 1 and 4, but the difference was of borderline significance at Week 8 (one-covariate analysis: p = 0.0529; two-covariate analysis: p = 0.0494). Subjects using the 1% alumina toothpaste had significantly higher gloss improvement scores than the reference toothpaste at Weeks 4 and 8, but not at Week 1. All three treatment groups' gloss scores improved during the study. Regarding tooth smoothness, the effects of the experimental toothpastes followed a broadly similar profile to the effects on tooth gloss. After four weeks' use, both experimental toothpastes were superior to the reference. After eight weeks' use, however, only the 2% alumina toothpaste approached significant superiority versus the reference (p = 0.0639).
  
  
  CONCLUSIONS
  The 1% and 2% alumina toothpastes improved tooth gloss compared to a standard silica toothpaste when used twice daily for two minutes over an eight-week study period. Furthermore, there was evidence of a corresponding increase in tooth smoothness.
authors.affiliation: Salus Research Inc., Fort Wayne, IN, USA.
authors.forename: Kimberly R
authors.initials: KR
authors.lastname: Milleman
authors.affiliation: Salus Research Inc., Fort Wayne, IN, USA.
authors.forename: Jeffery L
authors.initials: JL
authors.lastname: Milleman
authors.affiliation: GSK Consumer Healthcare, Weybridge, Surrey, UK.
authors.forename: Jonathan E
authors.initials: JE
authors.lastname: Creeth
authors.affiliation: GSK Consumer Healthcare, Weybridge, Surrey, UK.
authors.forename: Andrew
authors.initials: A
authors.lastname: Butler
authors.affiliation: GSK Consumer Healthcare, Weybridge, Surrey, UK.
authors.forename: Mary Lynn
authors.initials: ML
authors.lastname: Bosma
mesh_terms: D003743:Dental Enamel; D005459:Fluorides; D006801:Humans; D012822:Silicon Dioxide; D012969:Sodium Fluoride; D014089:Tooth Remineralization; D014099:Toothbrushing; D014100:Toothpastes
chemical_list: D014100:Toothpastes; D012822:Silicon Dioxide; D012969:Sodium Fluoride; D005459:Fluorides
keywords: alumina; enamel gloss; enamel smoothness