yagasil.blogg.se - New alginate impression material

Improper mixing – over or under mixing with unset powder left in the improession.

Defects: Can be caused due to the following reasons, which can be human errors or material problem.

Cannot be refined after taking the impression.ġ.

Cannot be manipulated once the impression is set.

Distortion may occur if tray is shifted during setting in the oral cavity.

Dimensional stability is poor, due to loss of water the impression sets to shrink overtime.

Comparatively poor tear strength especially in thin sections and inter dental areas in comparison to Elastomeric Impression material.

The impression cannot be electroplated.

impression can be removed easily & has pleasant taste & odor, so comfortable for the patient.

material is elastic & comes out easily from undercuts.

Used as duplicating material even in medical field for making artificial prosthesis like nose, ear, eyes etc.

Used for making impressions for the preparation of mouth protectors for athletes.

Used for making impression for orthodontic study models.

For construction of study models & temporary removable prosthesis.

Used for making impressions for dentulous patients.

Used for preliminary impressions for complete dentures.

Used for making primary impression of edentulous patients with undercut ridges.

Dustless alginate is also present in the market which contain glycol.

Silica present in the dust which rises from the can after fluffing alginate powder is a health hazard.

Elasticity & elastic recovery: highly elastic, permanent deformation less if the impression is removed from the mouth quickly.

lower w/p ratio results in lower flexibility.

Once its moistened rapid spatulation by swiping or stropping against the side of the bowl is done. The proper W/P ratio as pacified by the manufacturer should be used measured quantity of water and powder are added in the rubber bowl & mixing is started, with a stirring motion to wet the powder with water. The top of the can should be taken off carefully to prevent the silica particles from being inhaled. The Powder is taken after inverting the can several time to produce uniform distribution of the filler before mixing with water. Prolonged gelation time is tedious for both pt.Premature gelation causes distortion in the impression & it is rendered useless.By the amount of retarder added during manufacturer.The other ingredients used like Calcium Phosphate acts as a retarder which is used to manipulate or increase the setting time to an adequate Type I or Type II setting time as required. Setting takes place due to the reaction of Sodium Alginate reacting with Calcium Sulphate – this is the primary reaction which takes place. Reaction with Retarders to increase the setting time: Na Alginate + 3 CaSO4 -> Ca Alginate + 3Na2SO4.Primary reaction: 2Na3PO4 + 3CaSO4 -> Ca3 (PO4)2 + 3Na2 SO4.Ester salts of alginic acid(sodium or potassium or triethanolamine alginate) – 15%.Color changing alginates: violet during mixing, pink when ready to be seated and white when set.In medical practice the Alginate impression material is used widely to take impression or other parts of the Face like Nose, Ear etc to help make prosthetic organs. This process of conversion from powder to Gel and then solidifying into elastic material is used to take an impression of the oral cavity in dental clinics. Alginate material is available in powder form which turns into Gel when mixed with water and further converts into elastic material on manipulation. It is made from seaweed and is made with components like Sodium alginate, Calcium sulfate and other ingredients which act as retarders. They are there to help you feel comfortable.Alginate Impression material is an Elastic, Irreversible Impression material which is used to take the impression of both Dentulous and Edentulous Impressions. If you are worried about an active gag reflex, talk to your dentist. Precise impressions help dentists make custom fitting appliances that won't cause irritation or discomfort. Getting impressions of your teeth is an important part of restorative and orthodontic treatments. They may administer nitrous oxide, laughing gas, to stop the reflex and make you feel relaxed. Let your dentist know if you experience a gag reflex. The tray will be firmly placed on the upper or lower teeth (depending on where the dental work is being done) for a couple of minutes. The mixture is then spooned onto a u-shaped impression tray that will fit onto the arch of your teeth.

Once this is done, they will mix the alginate powder with water to create a smooth, spreadable consistency. Your dentist will start by cleaning the teeth to remove any debris and allow the mouth to partially dry. Making dental impressions happens during your initial consultations.