[Analysis of the point-counting and planimetric methods in the quantification of denture biofilm--a methodological validation study].
Two methods of quantification of the biofilm (point-counting and planimetric) were tested and compared with the paper-weighing method and with the Prosthesis Hygiene Index. The internal surfaces of 62 complete dentures were stained and photographed. The slides were projected on a paper sheet. The total area and the area covered with biofilm were contoured using a black pencil. The point-counting method (experimental 1) was carried out on a mesh of equidistant points. For the planimetric method (experimental 2), the areas of interest were measured by means of a digital planimeter. In the paper-weighing method (control 1) the areas of interest were cut and weighted on a precision scale. In the determination of the Prosthesis Hygiene Index (control 2), the accumulation of biofilm was estimated by means of a scoring method. The results revealed an agreement rate of 82% between the paper-weighing method and the point-counting method, and an agreement rate of 95% between the former and the planimetric method, which was confirmed by high coefficients of correlation (0.98 and 0.99, respectively). The comparison with the Prosthesis Hygiene Index resulted in 55% of agreement with the point-counting method and in 37% of agreement with the planimetric method. The experimental methods can be useful in clinical studies involving the evaluation of the performance of denture cleansers.
Fernandes
Roseana Aparecida Gomes
RA
Faculdade de Odontologia de Ribeirão Preto, Universidade de São Paulo.
Zaniquelli
Osvaldo
O
Paranhos
Helena de Freitas Oliveira
Hde F
D018441:Biofilms; D015169:Colony Count, Microbial / Q000379:methods*; D003778:Dentures
Análise dos métodos de contagem de pontos e planímetro na quantificação do biofilme da dentadura--um estudo de validação metodológica.