Adhesive
Adhesive , such as adhesive powder , adhesive cream , adhesive pads , adhesive strips or adhesive gel are used to improve maintenance of the prosthesis of dental prostheses used. In patients who suffer from pronounced jaw bone loss, these denture adhesives can help to improve the wearing comfort of the removable dentures. The adhesives are also helpful during the acclimatization period or when providing temporary dentures . Biting strength and chewing ability can be improved by using adhesives in a well-fitting prosthesis. By Gnathometermessungen that denture wearers could be demonstrated by application of an adhesive cream of an increase in the bite force benefited by about 75%.
Adhesives can also be helpful in the event of changes in muscle tone , for example due to paralysis of the facial muscles .
Basics
A dental prosthesis is held in the mouth by suction ( adhesion and cohesive forces ) on the jaw. For this purpose, the edge of the prosthesis is individually adapted using a functional impression. The edge of the prosthesis must seal the prosthesis. The soft tissues in the mouth can loosen or pry off the prosthesis with various mouth and tongue movements. The prosthesis must therefore allow the various muscle ligaments a range of motion, such as the frenulum of the tongue or the frenulum and cheek frenulum. In the lower jaw, the functional impression also takes into account the freedom of movement of the floor of the mouth . The floor of the mouth rises and falls in interaction with the tongue. The prosthesis must not be lifted off the lower jaw and levered out.
The hold differs between the upper and lower jaw prosthesis. With the latter, the grip is considerably lower due to the smaller contact surface, the reduced suction effect and the movements of the tongue . Experienced prosthesis wearers can hold the mandibular prosthesis in position using the tongue and cheek muscles.
The hold of a prosthesis depends on numerous factors. First of all, the shape of the jaw is crucial. The larger and more pronounced the alveolar ridge, the better the hold. The hold of a prosthesis can deteriorate over many years because the jawbone is subject to bone loss. In healthy dentition, the teeth are attached to Sharpey's fibers in the alveoli . When the teeth are loaded, tensile forces - and not compressive forces - result on the jawbone. Due to the piezoelectric forces, when the teeth and thus the jawbone are stressed, electrical potentials arise that have a positive effect on bone structure. In edentulous dentition, on the other hand, the pressure load on the dentures acts on the gingiva propria and thus on the jawbone below, which reacts with increased resorption .
The hold of the prosthesis also depends on the static design. This means that the denture teeth in their occlusion (clenching of the upper and lower jaw teeth ) must contribute to a stable position and must not cause the denture to be levered out by chewing movements.
Differences in occlusion compared to natural teeth
In natural dentition, the canine guidance ensures that the lower jaw is forced to open when it moves sideways (laterotrusion movement). As a result, the teeth in the posterior area get out of contact. The front teeth have the same effect when the lower jaw moves forward. In the case of a full denture , however, just guiding the front and canine teeth would cause the dentures to be levered out and tilted. For this reason, prostheses are ground in in such a way that there are no levering guide zones. Rather, balance contacts are consciously established. This means that when you move sideways, the teeth on both sides slide together in contact. When the lower jaw moves forward, the molars of the upper and lower jaw prosthesis slide over each other and provide distal support.
If necessary, the prosthesis wearer has to change their chewing habits and carry out a chewing pattern that is more like chopping movements. However, grinding movements of the jaws should be reduced.
Degradation of the alveolar ridge
In the first year after tooth loss, the alveolar ridge degradation is around 0.5 mm in the upper jaw and 1.2 mm in the lower jaw. In the following years the reduction is 0.1 mm in the upper jaw and 0.4 mm in the lower jaw. The faster breakdown of the lower jaw bone results, among other things, from the fact that the contact surface for a prosthesis is only about half the size of that of the upper jaw. In the upper jaw, the prosthesis also rests on the palate . As a result, the loading forces that act on the lower jaw are twice as great as in the upper jaw . As a result, after around 20 years of wearing the prosthesis, the alveolar ridge of the lower jaw is completely broken down and the lower jaw has become flat. It then no longer offers a hold for a full denture . In such cases , the jaw can be reconstructed using various jawbone reconstruction methods. The prosthesis can also be held in place with implants . In order for the jaw resection to take place as slowly as possible, the prosthesis must lie firmly on it. This must be done by relining (padding) the prosthesis at regular intervals of one to two years .
Duration of the adhesion of a prosthesis
The mucous membrane (mucosa) contains mucus-forming cells. The formation of slime is important for the adhesion of the prosthesis. The mucus has a function, similar to a liquid between two panes of glass, which makes them stick together better. Something similar can be observed when moistening a suction cup .
The mucous membrane usually forms mucus continuously. Too much mucus will gradually reduce the suction effect, as the increasing mucus gradually increases the distance between the prosthesis and the mucous membrane. Therefore the suction effect of the prosthesis only lasts for about 20 minutes. After this time has elapsed, the prosthesis must be pressed against the jaw again by clenching it firmly in order to attach it again. This clenching presses out the excess mucus between the prosthesis and the mucous membrane.
Bruises
If a prosthesis causes pressure points and hurts when chewing, then you will automatically not press the prosthesis firmly onto the jaw, which means that the prosthesis cannot suck in properly and thus cannot hold. Pressure points must therefore be removed by a dentist immediately. If the alveolar ridge bone is angular, a lining that remains soft can dampen the stresses of chewing and thus prevent pressure points. Plasticizers are added to the plastic . In addition, pressure points lead to mucosal ulcers , which can become infected and, in the worst case, degenerate. The healing of the pressure points can be accelerated by using adhesives.
How the adhesive works
The adhesive powder or the adhesive cream can hardly bring about an improvement in a poorly fitting prosthesis and cannot compensate for possible defects in a prosthesis. Provided the prosthesis “fits”, the adhesive causes a certain thickening of the mucus. The adhesives swell in the saliva and thus increase its viscosity. They form a film on the base of the prosthesis and thereby increase adhesion. The slime becomes thicker. The adhesive cream therefore does not stick the dentures in place, but ensures greater adhesion if the amount and consistency of the saliva are not sufficient to guarantee the natural hold.
For this purpose, the adhesive powder should be applied to the cleaned, moistened prosthesis outside the mouth as if salting a soup. Adhesive powder is more suitable for the upper jaw prosthesis. With an adhesive cream, it is sufficient to apply around four pea-sized portions, which are distributed over the lower jaw prosthesis. The prosthesis is then placed in the mouth and pressed firmly into place.
Too much adhesive can reduce the adhesion.
composition
Many manufacturers are cautious about the exact composition of the adhesive. They may contain, depending on the drug: methyl cellulose , sodium alginate , a mixture of the sodium - / calcium salts of the copolymer of methyl vinyl ether and maleic anhydride , carboxymethylcelluloses , paraffin , vaseline , aloe vera (barbadensis miller), silica , menthol , azorubine , paraffin, cellobiose or zinc . Alginates, the salts of alginic acid, are often used. Alginate is used as a thickening or gelling agent . Alginic acid is produced by brown algae and some bacteria (e.g. Azotobacter ).
zinc
Adhesive creams are on the market with and without the addition of zinc. Zinc has anti-inflammatory effects, relieves pain and promotes wound healing. Parts of the adhesive are naturally swallowed. A high zinc intake over a longer period of time can lead to a copper deficiency caused by the zinc-induced inhibition of copper uptake in the small intestine , which also leads to severe neurological symptoms such as numbness, tingling and weakness of the limbs (extremities), difficulty walking and balance disorders as well as anemia ( anemia ), headache , nausea , constipation, or poor appetite . If used daily, preference should be given to a zinc-free alternative, especially if it is used more than once a day or if a tube containing 40 grams is consumed in less than 6 weeks. Herbal additives such as chamomile or aloe vera have equivalent properties for reducing pain and inflammation .
variants
Adhesive cream, adhesive cushions, pads, adhesive strips or adhesive gel also fill any small cavities that may exist between the prosthesis and the mucous membrane. To a certain extent, they represent short-term - not particularly suitable - "relines". These products are not washed away in the lower jaw as quickly as adhesive powder. Some creams have to be applied to the dry denture, others to the moistened denture.
Adhesive pad
Adhesive cushions are foils made of an elastic plastic material that becomes soft and cuddly through body heat. They suck on the jaw and last up to three weeks. The adhesive pad is pressed onto the cleaned and well-dried prosthesis. The air bubbles are removed and the pillow is cut to size. The adhesive pad remains on the prosthesis during the daily cleaning of the teeth. Components are polybutylene , methacrylate , polypropylene laurate , titanium dioxide , iron oxide pigment .
Adhesive strips
Adhesive strips (adhesive pads) are made of fine, palate- friendly fleece fabric that contains sodium alginate. The adhesive strips are shaped in the form of a prosthesis for the upper and lower jaw and can be cut to the appropriate size if necessary. They are placed on the damp prosthesis. Like the other adhesives, adhesive strips must be changed every day, otherwise they are a particularly good breeding ground for germs that can cause inflammation .
Denture cleaning
The adhesive must be completely removed at least once a day during denture cleaning. Dentures should at least be rinsed with water after each meal, after which the adhesive can be reapplied. At the same time, the mucous membrane in the mouth (palate and alveolar ridge) must be cleaned with a soft brush, and residues of the adhesive must be removed. For cleaning a prosthesis, the trade has special prosthesis brushes.
Precautions
- By using adhesives immediately after the prosthesis has been manufactured, undesired errors in fitting the prosthesis can be concealed.
- Adhesives can be aspirated.
Chewing pressure
In fully edentulous teeth with completely healthy teeth, the maximum biting force is 50 kp for the first molar region and 40 kp in the premolar zone. In comparison, full denture wearers can generate a maximum biting force of only about 5 kp in the posterior region. Ideally, this chewing pressure is achieved through the better adhesion of the prosthesis due to the adhesive powder.
Bite off
The ability to bite off with a prosthesis depends primarily on whether the maxillary tuberosities are pronounced. The prosthesis can then encompass the paratubar space. If the tubera is missing, the ability to bite off cannot be achieved even with adhesive. The prosthesis then tilts at the back when biting off. If the tuberosity is sufficiently pronounced on at least one side, the contralateral side can be bitten off from the side.
Individual evidence
- ↑ H. Stark, and KP Wefers, Investigations on the utility value of prosthesis adhesive cream, Quintessenz J. 49, 991-997 (1998).
- ^ A. Slaughter, RV Katz, JE Grasso: Professional attitudes toward denture adhesives: A Delphi technique survey of academic prosthodontists. In: The Journal of prosthetic dentistry. Volume 82, Number 1, July 1999, ISSN 0022-3913 , pp. 80-89, PMID 10384167 .
- ↑ a b N. Schwenzer, M. Ehrenfeld: Tooth-mouth-jaw medicine. 5 volumes, volume 3: Dental surgery . Thieme Verlag, Stuttgart 2000, ISBN 3-13-116963-X in Googlebooks
- ↑ Klaus M. Lehmann, Elmar Hellwig, Hans-Jürgen Wenz: Dental Propaedeutics: Introduction to Dentistry; with 32 tables . Deutscher Ärzteverlag, 2012, ISBN 978-3-7691-3434-6 , p. 361 ( google.com ).
- ↑ a b c d Ricki Nusser-Müller-Busch: The therapy of the Facio-Oralen Trakt: FOTT after Kay Coombes . Springer, 2013, ISBN 978-3-662-06690-4 , pp. 104 ( google.com ).
- ↑ COREGA takes adhesive creams off the market: health risk , product recalls. Retrieved March 25, 2015.
- ↑ Beware of excessive use - too much zinc can be harmful , paradisi. Retrieved March 25, 2015.
- ↑ Ammar Leyka, Changes in biting force after renewal or relining of total prostheses , dissertation, 2001, p. 15. Accessed on March 26, 2015.
