fioreox.blogg.se - Alginate impression material dental

This can be avoided with the use of petroleum jelly.

The material tends to stick to the lips and surrounding skin.

It can't reproduce undercuts, so is unsuitable for partial denture impressions.

The disadvantages of impression paste include: This is done by adding fresh paste and inserting into the mouth until set.

Its accuracy can be improved by retaking the impression.

The advantages of impression paste include: When the products are mixed together they will create a different colour there should not be any red or white streaks remaining. The mix should then be loaded into a special tray for secondary impressions of the edentulous arch. When using this product equal amounts of each paste should be squeezed onto a pad and mixed with a spatula. It comes in two tubes: one containing a white zinc oxide mixture and the other containing a red eugenol mixture. Other properties are added to make it suitable to use as an impression material. Impression paste is a modified form of zinc oxide eugenol. It is therefore used for primary impressions of edentulous arches. It doesn’t flow well and can't record fine detail.

Impression compound must be heated in a water bath and then moulded onto the impression tray. The rigid materials are usually used to record impressions of edentulous arches only. Rigid impressions (impression compound & zinc oxide eugenol) Non-elastic materials are generally not used for taking impressions of crown preparations because of their inability to accurately record undercuts. Impression materials are commonly classified by their elastic properties once set. Each material is used for different purposes, as some laboratories require a more detailed impression than others. They can be categorised into either rigid impression materials (zinc oxide eugenol and impression compound) or elastic impression materials (alginate and silicone). There are four main types of impression material that are routinely used in dentistry. Certificate in Dental Reception and Management.Level 3 Certificate Dental Practice Management.Certificate in Fluoride Varnish and Plaque Indices.

Certificate in OHE, Plaque Indices & Fluoride Varnish.NEBDN National Diploma in Dental Nursing.Both the permanent set and tear energy are affected by the filler particle morphology. Bond rupture can be reduced by increasing the alginate content in the system which also raises the tear energy. Although this process of bond interchange and that of continued polymerization during deformation may be contributory mechanisms to permanent set, bond rupture appears to be the primary mechanism. The Ca2+ crosslinks bridging the alginate chains in the network appear to be labile. The gelation time is primarily controlled by the concentration of Na4P2O7 in solution acting as a retarder, while the level and particle size of the alginate and CaSO4 X 2H2O also affect the kinetics through the dissolution rates and concentration effects. Structural information was also obtained from the dependence of viscosity and compressive modulus on the calcium concentration in model systems. The setting behavior of calcium alginate impression materials was investigated by monitoring the viscosity, calcium ion activity, and shear modulus during the reaction.