title: Evaluation of physical-mechanical properties of 3 brands of plaster of Paris in the Kenyan market.
abstract: In this study, 3 brands of plaster of Paris that are available in the Kenyan Market for prosthetics and dental rehabilitation uses were subjected to physical-mechanical tests. The particles in two of the brands that had been imported were finer than a locally made plaster since less than 1.41% of their particles were larger than 150 microns compared to 15.2% in the local plaster. The range of their setting times was between 7.5 and 27.5 min. and was within the International Standards Organisation (ISO) recommendation. The water:power ratios required to produce plaster mixes of standard consistency for the locally made plaster was about 1.5 times of other brands. In compression, the mean 1-hour strength of local plaster was 2.5 MN/m2 (Mega Newtons per square metre) compared to 6.81 MN/m2 and 8.95 MN/m2 for the other brands. The differences between these strength values were highly significant (p less than 0.01). There were no significant differences in deformation of fracture for the 3 brands whose range was 1.32% to 1.71%. In order to obviate the need to import plaster, strict manufacturing techniques of locally made plaster are recommended.
authors.affiliation: Kenya Medical Research Institute, Medical Research Centre, Nairobi.
authors.forename: D L
authors.initials: DL
authors.lastname: Mwaniki
mesh_terms: D002133:Calcium Sulfate / Q000592:standards* / Q000600:supply & distribution; D006801:Humans; D007394:International System of Units; D007630:Kenya; D055585:Physical Phenomena; D010825:Physics; D012015:Reference Standards
chemical_list: D002133:Calcium Sulfate