Mucostatic are impressions that record the tissues with minimum displacement. Mucodisplacive are impressions that displace the tissues. The choice is made by the dentist on the basis of oral conditions, concept of the function of the tissues surrounding the denture and ability to handle the available impression materials.

Typical oxide composition of dental porcelain: 1. silica 2. alumina 3. boric oxide 4. potash 5. soda Three stages of production 1. Compaction 2. Firing 3. Glazing Compacting 3 basic types of dental porcelain powder are used, opaque shade, dentin shade and enamel shade Firing Initially crown is heated to remove excess water, once dried [...]

Natural Tooth Versus Implant Characteristics under Load Criterion Tooth Implant Connection Periodontal Ligament Function Ankylosis Impact Force Decreased Increased Mobility Variable Anterior teeth more than posterior teeth None Movement Shock breaker effect of Periodontal Ligament Stress captured at crest Apical Intrude quickly 28 micrometer 10 to 50 micrometer Diameter Large Small Cross Section Not round [...]

Terminologies to Describe Metals Noble Metals are Gold, Platinum, Palladium and other inert metals. Precious Metals are noble metals and Silver. Base Metals do not contain noble elements. Zinc, Chromium. Non-Precious Metals are stainless steel, aluminum alloys, cobalt chromium, nickel chromium, Titanium. Stainless Steel is used in Pedo Crowns. Cobalt Chromium Alloy is used in [...]

Impression Materials are used to record the shape of the teeth and alveolar ridges. Classified as: 1. Elastic 2. Non-elastic Elastic Impression Materials Impression Materials which can be stretched and bent to a fairly large degree without suffering any deformation. These are used for recording oral structures where undercuts are present. The Elastic Impression Materials [...]

Impression Materials are used to record the teeth, alveolar ridges, oral, and maxillo-facial structures. Elastic Impression Materials 1. Hydrocolloids A. Agar-agar B. Alginates 2. Elastomers A. Polysulphides B. Silicones i. Addition ii. Condensation C. Polyethers Non-Elastic Impression Materials 1. Impression compound 2. Impression Plaster 3. Zinc Oxide Eugenol 4. Impression Waxes

When mechanics is applied to biomaterials it is called biomechanics. It is how well materials behave in real structures, It is the application of the principles of engineering to the human body. Biomechanics is also how well the materials withstand the forces generated from the action of mastication and occlusion. Considerations of Biomechanics are Important [...]

Biomaterials When a material is placed in contact with the human body Non living material designed to interact with biological system. Three main areas of use 1. dental restorative materials 2. structural implants 3. cardiovascular implants Biocompatibility Non destructive in the biological environment. The biological interaction can take place either at a local level or [...]