Measurement of surface hardness of primary carious lesions in extracted human enamel -measurement of Knoop hardness using Cariotester.
The clinical feasibility of a novel device called a Cariotester was investigated by measuring the Knoop hardness (KHN) of white spot lesions diagnosed as ICDAS code 1, 2 or 3. To obtain an equation for converting the Cariotester indentation depth into the KHN, a regression analysis was performed between the depth and measured KHN for human enamel. The Cariotester was then used to measure the indentation depth for white spots (ICDAS code 1, 2 or 3) in extracted teeth, and the KHN values were determined using the above equation. The KHN was 219.9±19.7, 162.4±24.0 and 31.7±17.5 for code 1, 2 and 3 lesions, respectively, which was 30, 49 and 90% lower than that for healthy enamel. Using the formula reported in the literature, the mineral density was calculated to be 87.7 vol.% for healthy enamel, and 75.1, 66.1 and 35.5 vol.% for code 1, 2 and 3 lesions, respectively.
Department of Dentistry and Oral Surgery, Hyogo College of Medicine.
Akihiko
A
Shimizu
Takatsugu
T
Yamamoto
Syozi
S
Nakashima
Toru
T
Nikaido
Toyotaro
T
Sugawara
Yasuko
Y
Momoi
D003731:Dental Caries / Q000473:pathology*; D003743:Dental Enamel / Q000473:pathology*; D003804:Dentin / Q000473:pathology; D006244:Hardness; D006801:Humans; D012044:Regression Analysis