Lecture No. 5 dental cements used in orthopedic dentistry

General characteristics of the material

Dental cement

It contains powder and liquid, when mixed, a paste-like mass is formed.
Dental glass is used to mix dental cement .

An accompanying attribute is dental glass for mixing cement, available without a hole, with 1, 2, 3 holes

During the hardening process, the mass begins to harden and becomes like stone. Hardening occurs as a result of the components entering into a chemical reaction.

The main indicators that high-quality dental cement

, the following:

• mixing time;
• work time;
• curing time.

Mixing time refers to the period of time recommended for preparing the solution. Typically this figure is 90 seconds , and it is not recommended to exceed it.

The time during which the doctor must have time to apply the mixture to the tooth and model the filling is called working time. Each manufacturer of dental cement has its own characteristics, but the average varies from 4 to 10 minutes .

The period allotted for hardening of the cement mass also varies among manufacturers. Sometimes it can take a week for the ingredients to react and cause hardening. An important role in the setting of the material is played by the temperature and mixing proportions of dental cement.

with liquid.

Types of dental cements for fixation of fixed dentures and crowns - classification

Today, the dental clinic market offers a lot of different compositions that are used to permanently secure permanent crowns and dentures in the patient’s oral cavity.

There are four main types of cement identified through experiments conducted by scientists and specialists over the past ten years. Their classification depends on the type of binding component present in the matrix and the specific indications for use.

Zinc phosphate dental cement for fixation of crowns and dentures

It is the oldest of the dental cement compositions that dentists now practice.

Mix immediately, right before use. It contains 65-70% powder, represented by magnesium or zinc oxides, and the liquid part is an aqueous solution of phosphoric acid.

Application

• Installation of single crowns and bridges on 3-4 teeth in patients without hypersensitivity.
• Fixation of pin structures on a well-preserved root protruding above the gum.
• Prosthetic bridges for more than 4 teeth.

Polycarboxylate cement for crowns

The powder combines zinc oxide and tin fluoride. The liquid part contains water and polyacrylic acid.

Characteristics of polocarboxylates:

• lowest adhesiveness and strength;
• excellent biocompatibility, the likelihood of allergies or irritation is almost zero;
• a thin layer of composition is required;
• serves as an additional prevention of caries.

Polycarboxylate cement for fixing crowns is ideal for fixing single crowns with increased tooth sensitivity. For all other clinical situations, there are better options.

Glass ionomer cement for fixation of crowns and fixed dentures

The liquid part of glass ionomer cement is represented by polyacrylic acid, and the powder part is not similar to those described in this material.

Aluminosilicate glass contains a high fluorine content.

Arde Kwik Tsem

The German drug Arde Quick Cem is a dual-curing microhybrid cement intended for fixation of dental structures in the form of veneers (both light-conducting and non-light-conducting), intracanal pins, bridges, crowns, etc.

Mixing cement can be done either automatically (in cannulas and syringes) or manually. The main advantages of Arde Quick Cem:

1. increased fluidity (with the help of intraoral attachments, good filling of small posterior and anterior carious cavities that are difficult to access is ensured);
2. high radiopacity;
3. possibility of automatic mixing without the formation of air bubbles;
4. relatively low price.

Arde Fix

Chemically cured German (Ardenia) glass ionomer cement is designed primarily for fixation of various dental structures - bridges, crowns, intracanal pins, onlays, orthodontic rings.

Arde Fix provides:

1. high adhesion to dental tissues and orthodontic structures;
2. guaranteed (chemical) polymerization, which ensures reliable fixation of internal structures, in particular intra-channel pins;
3. non-oxidation and practical insolubility in oral fluids.

Fuji Plus

Fuji plus is a Japanese glass ionomer cement reinforced with a composite, and according to its main purpose it is classified as a fixing material.

With its help, various metal-composite, metal and metal-ceramic orthodontic structures are attached - inlays, dentures, bridges, crowns, intracanal pins.

The combination of a glass ionomer with a composite provides Fiji Plus a wide range of indications.

The material has:

1. mechanical characteristics close to composite cements;
2. high chemical adhesion to dental tissues, good adhesion to polymers, metals, ceramics;
3. precise and easy fitting due to the thin film thickness;
4. radiopacity, which makes diagnosis accurate;
5. constant fluoride release.

Ketak Tsem

Ketac Cem is a hand-mixed GRC intended for the cementation of bridges, crowns made of various materials, and onlays.

Ketac Cem:

1. has high chemical adhesion to orthodontic structures and tooth tissues;
2. non-toxic, biocompatible with dental tissues;
3. releases fluoride for a long time;
4. does not require an absolutely dry surface;
5. close in thermal expansion to dental tissues;
6. provides high-quality edge fit and high wear resistance;
7. has 5 color shades.

The only disadvantage of cement is its relatively high price. But given the 25-year documented history of successful international application, this disadvantage cannot be considered so significant.

Tsemion F

Cemion F Russian is a two-component material designed for fixation of various endodontic structures - crowns, inlays, intracanal pins, bridge prostheses.

The delivery set includes powder, which is a material based on polyacrylic acid and fluorosilicate glass, conditioner and solvent.

The advantages of Tsemion F include:

1. abrasion resistance;
2. high strength;
3. good adhesion to tooth tissues and materials of endodontic structures;
4. radiopacity;
5. anti-carious properties due to the long-term release of fluoride;
6. low cost.

Composite cement for crowns

The only type of all types is represented by two separate pastes. The first is basic, the second contains a catalyst.

Properties of composites:

• have record strength;
• decent level of adhesiveness;
• unfortunately, they often cause allergies;
• do not dissolve with saliva and other liquids;
• have excellent aesthetics.

The scope of application of composite cement for fixing crowns is quite wide:

• ideal for fixing any ceramic products - crowns, veneers, lumineers;
• are the optimal choice when installing any pin structures;
• are also well suited for any type of prosthetics, provided that the patient does not suffer from increased tooth sensitivity.

Composites are not recommended only for people with an increased tendency to secondary caries and high enamel sensitivity.

Application

1. Permanent fixation of a wide variety of ceramic products (crowns, veneers, lumineers).
2. The best choice when installing various pin structures.
3. Prosthetics of any kind, if the patient does not have increased tooth sensitivity, etc.

Properties

• Record strength.
• High adhesiveness.
• Great aesthetics.
• Resistant to saliva and other liquids.
• Risk of developing allergies.

ATTENTION : Doctors do not recommend the use of composites when installing crowns, etc., for people who have an increased tendency to secondary caries, as well as high enamel sensitivity.

Polymer modified glass ionomer cement for fixation of crowns

It is considered the most advanced material for fixing crowns; it is supported by the combination of the advantages of composites and glass ionomers, as well as the content of a significant proportion of natural resins.

Production of filling material

When developing a high-quality mixture for use in dentistry, manufacturers strive to ensure that its composition closely resembles the natural, inherent component of the tooth. For this purpose, additives are used that divide dental cement.

into several types:

• phosphate;
• polycarboxylate;
• polymeric;
• silicophosphate;
• glass ionomer.

Each subtype of cement is used in certain cases of oral treatment. The phosphate type is used for filling teeth with increased chewing load; polycarboxylate solution is characterized by rapid hardening. Polymer cement does not leave gaps between the gums; the silicophosphate type is good for its increased plasticity properties, and the glass ionomer solution is hypoallergenic and color resistant.

From the family of dental cements: Silicin Plus, Cemilight, Cemion, Uniface-2...

When contacting your dentist, ask him what materials are used to treat your tooth.
You can also choose the type of cement yourself, having previously studied its features and consulted with your dentist about the advisability of using it. Moscow metro station Zvezdnaya, Danube Avenue, 23

In what cases is it necessary to fix dental crowns?

Attaching dental crowns allows you to connect the structure to the dental tissue. How long the structure will last depends on this stage. High-quality installation of dentures provides relief from the negative impact of the external environment, one of the manifestations of which is caries. If the crown falls out, it can be glued back.

Causes of crown loss

The main cause of crown loss is most often sticky or hard food. But also some patients develop secondary dental caries . This can happen with improper treatment and installation of a denture, when the hard remaining tissues under the denture are poorly cleaned and provoke the development of bacteria and microbes.

Bad habits such as cracking nuts, chewing a pencil or pen can lead to crown loss.

Very rarely, some patients may experience an allergic reaction and incompatibility of materials with dental tissues.