This experiment was performed in order to measure the toxicity of a fixative cream for dentures on reconstituted human oral epithelium.

For each of the tested products or controls, at the end of the incubation period, two cultures are rinsed and placed on 300 µl of 0.5 mg/ml MTT.
After 3 hours of incubation at 37°C, 5% CO2, cultures are placed in 1.5 ml of isopropanol. Extraction is performed at room temperature, for a minimum of 1.5 hour at room temperature. Optical density is measured on 200 µl of extracts at 570 nm (reference filter: 690 nm). Results are expressed as percentage of viability compared to negative control (mean +/- SD of duplicate cultures).
% of viability = [OD(570 nm - 690 nm) test product / OD(570 nm - 690 nm) negative control] x 100.

For each of the tested products or controls, at the end of the incubation period, one culture is fixed in a balanced 10% formalin solution and later embedded in paraffin. Four micron vertical sections are stained with hematoxylin/eosin, and photographed under a microscope.

* Histo-pathologic interpretation:
Negative control cultures: The epithelial tissues must have a constant thickness (corresponding to the internal control sections), devoid of terminally differentiated cells, and a regular and compact shape. Cells are attached to the others via multiple desmosomes.

Positive control cultures: Most of the upper cell-layers of the epithelial tissues must be disintegrated, and the remaining basal cells loosely attached to the polycarbonate substratum.

Differential release of pro-inflammatory mediators by a model of oral mucosa after challenge by oral health products and other compounds. A. Chruchley. 2nd International SkinEthic Workshop 'In vitro Reconstituted Human Tissue Models in Applied Pharmacology and Toxicology Testing', Nice, France, October 2003.


Three dimensional constructs of the human oral mucosa and the gingival epithelium for in vitro toxicology. B. Vande Vannet. 2nd International SkinEthic Workshop 'In vitro Reconstituted Human Tissue Models in Applied Pharmacology and Toxicology Testing', Nice, France, October 2003.


Toxicity of soldered and laser welded archwires in threedimensional cell cultures. B. Vande Vannet, J.L. Hanssens, H. Wehrbein. European J. of Ortodontics, 25, 5, p.565, 2003.


Toxicity of used orthodontic archwires in three-dimensional cell cultures. N. Mohebbian, B. Vande Vannet, H. Wehrbein. Presented at the 77th European Orthodontic Society Congress, Ghent, Belgium, June 2002.


Release of prostaglandin E2, IL-6 and IL-8 from human oral epithelial culture models after exposure to compounds of dental materials. G. Schmalz, H. Schweikl, K.A Hiller. European Journal of Oral Sciences, 108, p. 442-448, 2000.