What are the advantages and disadvantages of alginate impression material?

Alginate

It is inexpensive and can produce impressions with reasonable surface detail. Disadvantages: poor dimensional stability, poor tear strength, distortion if unsupported, requires good mixing otherwise air bubbles, minimum 3mm thickness required.

What is advantages of alginate impression material?

Alginate impression materials are easy to use, less expensive, with quick setting time. The setting time can be controlled with the temperature of water used. They are mildly flavored.

What is a disadvantage of alginate?

alginate represents alginate's most common salt. However, due to its characteristics, alginate also has a number of limitations, such as a poor stability or low mechanical and barrier properties, incompatibility with heavy metals and heat treatment instability, some of which cannot be corrected later ( Figure 2).

What are the disadvantages of reversible hydrocolloid material?

The disadvantages are the initial start-up cost of the conditioning unit, casts must be poured immediately, and the material has a low tear strength when impressing narrow, deep sulci. When using agar (reversible hydrocolloid) impression material, the tray is removed with a snap-out method.

What are the properties of alginate impression material?

Properties: Taste & odor: ·Pleasant. Flexibility:·lower w/p ratio results in lower flexibility. Elasticity & elastic recovery: highly elastic, permanent deformation less if the impression is removed from the mouth quickly.

ALGINATE || IMPRESSION MATERIAL || DENTAL MATERIALS

What are the uses of alginate?

Alginates are used to coat fruits and vegetables; as a microbial and viral protection by-product; and as a gelling, thickening, stabilizing, or emulsifying agent in food factories (Gheorghita Puscaselu et al., 2020).

What are alginate impressions used for?

Alginate impression can be used for the fabrication of a primary cast in prosthodontics, study models in orthodontic, and duplication of casts. In one study, it was shown that alginate impressions could also be used as final impressions for indirect restorations with chamfer finish lines.

Why is alginate irreversible?

Agar is a reversible hydrocolloid because it can pass repeatedly between highly viscous gel and low viscosity sol simply through heating and cooling. However, alginate once converted to the gel form cannot be converted back into the sol, and is therefore said to be irreversible hydrocolloid material (4).

What are some of the advantages of polyether impression material?

Polyether provide good accuracy and sur- face detail as well as low shrinkage upon setting. Its flexibility is also very low and stiffness is high (3,12).

How is an alginate impression disinfected?

Irreversible hydrocolloid (alginate) and hydrophilic silicones distort when immersed and can be disinfected by spraying and placing in a sealed plastic bag for manufacturer's recommended time.

What are some of the types and common causes of failures encountered with the alginate impression materials?

How long can alginate impressions last?

Numerous studies have evaluated the dimensional accuracy of conventional alginates [2,7–15]. Some studies show that it is possible to store a hydrocolloid impression for up to 1, 2 and even 4 hours [8–10].

What are the two types of alginate?

Alginates are made up of two uronic acids: d-mannuronic acid (M) and l-guluronic acid (G) extracted from brown seaweeds Phaeophyceae and kelp [68,69]. The alginic acid form of alginate is extracted from the seaweed in alkaline conditions, then precipitated and ion exchanged (e.g., with potassium).

What is the most important function of an impression material?

Impression materials are used to copy the teeth and surrounding oral structures by creating a dental impression poured with dental plaster to fabricate a dental cast. This procedure provides a tridimensional and accurate mouth replica, allowing dental work even in the absence of the patient.

What is the working time of alginate?

ADA divides alginate setting time into two type, they are type I fast set with 75 s working time and 1-2 minutes setting time, type II normal set with 2 minutes working time and 2-4.5 minutes setting time [7].

Which impression material is most flexible?

Alginate would be considered the most flexible of the impression materials, whereas polyethers would be considered the least flexible.

Which impression material has the best wettability?

Polyetheric materials, A-silicones with added surfactants and C-silicones were found to have a good wettability. Alginate was found to be the most hydrophilic material, but this quality decreases in time.

What is the most accurate impression material?

1. The polyethers produced the most accurate complete-arch replicas. The second most accurate were the vinyl polysiloxanes, followed by the polysulfides and the irreversible-reversible hydrocolloids. The least accurate were the reversible hydrocolloids and the irreversible hydrocolloids.

Is alginate water soluble?

Alginic acid and calcium alginate are water-insoluble. All the alginate salts are insoluble to fats & oils and organic solvents.

How do you store alginate impressions?

For maximum accuracy alginate impressions should be poured up in the model material as soon as possible. If for some reason they cannot be prepared directly, they should be stored in 100 relative humidity in a plastic bag or wrapped in a damp (but not wringing-wet) paper towel.

Why is alginate impression material one of the most common forms used in dentistry?

Alginate impression materials are easy to use, less expensive and have more rapid setting times. The reaction time and therefore the setting time can be controlled with the temperature of the water used.

Why is alginate important in dentistry?

Because alginate impression material reacts favorably to water, it produces accurate dental impressions even in the presence of saliva. An accurate impression of your teeth and gums will help your dentist recreate a model of your dental arch. This will then be used to customize the dental device.

What alginate means?

An alginate is a polymer derived from alginic acid and used as a thickener, binder, or lubricant. Alginates are polymers known for their gelling and thickening properties. The sodium salt of alginic acid, sodium alginate, is used to make substances thicker.