Biomaterial Database

Evaluation of physical-mechanical properties of 3 brands of plaster of Paris in the Kenyan market. 1990

D L Mwaniki

Kenya Medical Research Institute, Medical Research Centre, Nairobi.

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.

UI	MeSH Term	Description	Entries
D007394	International System of Units	A system of physical units in which the fundamental quantities are length, time, mass, electric current, temperature, luminous intensity, and amount of substance, and the corresponding units are the meter, second, kilogram, ampere, kelvin, candela, and mole. The system has been given official status and recommended for universal use by the General Conference on Weights and Measures.	SI Units,Systeme International d'Unites,SI Unit,Unit, SI,Units, SI
D007630	Kenya	A republic in eastern Africa, south of ETHIOPIA, west of SOMALIA with TANZANIA to its south, and coastline on the Indian Ocean. Its capital is Nairobi.	Republic of Kenya
D010825	Physics	The study of those aspects of energy and matter in terms of elementary principles and laws. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Physic
D012015	Reference Standards	A basis of value established for the measure of quantity, weight, extent or quality, e.g. weight standards, standard solutions, methods, techniques, and procedures used in diagnosis and therapy.	Standard Preparations,Standards, Reference,Preparations, Standard,Standardization,Standards,Preparation, Standard,Reference Standard,Standard Preparation,Standard, Reference
D002133	Calcium Sulfate	A calcium salt that is used for a variety of purposes including: building materials, as a desiccant, in dentistry as an impression material, cast, or die, and in medicine for immobilizing casts and as a tablet excipient. It exists in various forms and states of hydration. Plaster of Paris is a mixture of powdered and heat-treated gypsum.	Dental Gypsum,Dental Stone, Artificial,Gypsum,Plaster of Paris,Alabaster,Anhydrous Sulfate of Lime,Artificial Dental Stone,Calcium Sulfate (1:1), Dihydrate,Calcium Sulfate (1:1), Hemihydrate,Calcium Sulfate (2:1),Calcium Sulfate Dihydrate,Calcium Sulfate, Anhydrous,Calcium Sulfate, Dihydrate,Calcium Sulfate, Hemihydrate,Calcium Sulphate,Drierite,Gypsite,Gypsum, Dental,Karstenite,Stone, Artificial Dental
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D055585	Physical Phenomena	The entities of matter and energy, and the processes, principles, properties, and relationships describing their nature and interactions.	Physical Concepts,Physical Processes,Physical Phenomenon,Physical Process,Concept, Physical,Concepts, Physical,Phenomena, Physical,Phenomenon, Physical,Physical Concept,Process, Physical,Processes, Physical