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 [...]

Oral Maxillofacial Prosthodontics: Ocular Impression The defect should be anesthetized with 0.5% tetracaine hydrochloride ophthalmic solution topical anesthetic to increase comfort during the impression procedure. Alginate impression material is mixed and expressed into the defect under the lids while the patient gazes directly forward at a fixed point at least 6 feet away. This will [...]

Complete Cast Crown Preparation Complete Cast Crown is an all metal restoration often used on single posterior teeth as a retainer for a Fixed Partial Denture. It provides greater retention and resistance than any other type of restoration. Steps Depth grooves for occlusal reduction minimum clearance on noncentric cusps 1 mm centric cusps 1.5mm Functional [...]

Fixed Partial Denture – Tooth Preparation Margin Designs Feather edge Conservative of tooth structure Does not provide sufficient bulk Not recommended Chisel Edge Conservative tooth structure Location of margin difficult to control Occasionally on tilted teeth Bevel Removes unsupported enamel, allows finishing of metal Extends preparation into sulcus if used on apical margin Facial margin [...]

Factors when replacing posterior teeth with an Implant Supported Fixed Partial Denture. 1. Posterior placement of implants of adequate lngth may be inhibited by anatomic features such as location of mandibular Canal. 2. If there are natural teeth in the opposite jaw, sufficient space may not be available for the abutments or to provide sufficient [...]

Definite Pressure Impressions would press the tissues in the same manner as chewing forces, thus ensuring contact during chewing. Minimal Pressure Impressions nonpressure impression techniques do not exist. Mucostatic Impression is based on Pascal’s Law which state that pressure on a confined liquid will be transmitted thorughout the liquid in all directions. Selective Pressure Impression [...]

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 [...]

Common Causes of Tooth Loss in Older Adults 1. Perio disease 2. Root caries 3. Tooth wear 4. Systemi disease 5. Poorly designed dentures