Clasp prostheses: manufacturing steps and technology
At present, the achievements of science have advanced far ahead. To correct congenital or acquired defects of the dentoalveolar system is now quite possible. And it can be done not only in children, but also in adults. Let's try to figure out what the clasp dentures are, the stages of manufacturing such structures will also be considered.
Assignment of denture prosthesis
This type of prosthesis is excellent in strength, so this design is used widely enough in dentistry:
- To eliminate tooth defects at the end of the dentition.
- For treatment of lateral pathology.
- As removable dentures when replacing teeth of the front row.
- For prosthetics of staggering teeth.
If a dentist for orthopedic treatment recommends using clasp dentures on attachments, the result will exceed all your expectations. Such designs are not only light, but also look beautiful, practically do not differ from real teeth.
What is a clasp prosthesis?
If we consider clasp dentures( the manufacturing steps will be described later), then they represent an arc consisting of three main parts:
- Cast frame of durable metal.
- Imitating gum plastic base.
- Artificial teeth, which are fixed on the basis.
To enable the installation of such a prosthesis, you must have at least a couple of your teeth, then the design can be reliably secured.
Varieties of denture prosthesis
In order to consider the laboratory stages of manufacturing a clasp prosthesis, it is necessary to know what kinds of such designs are. They are classified more often by the method of attachment in the oral cavity.
- Locking prosthesis on attachments. Reliably fixed on the supporting teeth with the help of a crown and special micro-locks, which are completely invisible, because they are mounted directly into the prosthesis. This is ideal when you need to restore the dentition when you lose a few teeth. The steps of manufacturing the clasp prosthesis on attachments will be described below.
- Clamping. The prosthesis has a clamping attachment and evenly distributes the load on the jaw. It is easy to use, as it is easily pulled out and put in place.
- Telescopic. Prostheses on telescopic crowns are the most expensive. Work on their manufacture requires high accuracy and care. The main elements of the prosthesis are a conical base and a tooth crown with a cavity inside, ideally repeating the shape of the base. The base on which the design is worn can be a sharpened tooth or an installed crown. This design provides a stable and reliable fixation.
Stages of manufacturing clasp prosthesis on clasps are much less laborious. They are easier to make, and they are fastened with small, but strong hooks on the teeth. But the disadvantage of this design is that when you smile or talk, hooks can be visible. A much more aesthetic look prostheses on attachmenah. These are small locks, but they firmly and reliably fix the prosthesis on the supporting teeth.
Recently, more and more popular designs on telescopic dental crowns.
Stages of manufacturing clasp prosthesis with lock fixation require more laborious work, which certainly affects their cost.
What materials are used for the denture prosthesis
All parts of the prosthesis are made using a variety of materials. The frame can be metal or plastic. If plastic is used for a nonmetallic part, steel or alloys, for example, chromium-cobalt or gold-platinum, are used for the metal.
The steel structure has its drawback - an oxide film is formed at the place of soldering. And this indicates that the process of oxidation of solder in the oral cavity is in progress. For this reason, nowadays steel parts are used less and less often, preference is given to solid-cast structures.
Technologies for obtaining a clasp prosthesis
All must, of course, understand that it is possible to make such a complex construction only in a dental laboratory. To do this, use various methods:
- Casting of the structure with removal from the workpiece of the wax model. This technology involves removing the structure of wax from a gypsum model and packing it into a refractory mass. The wax is removed and replaced with liquid metal.
- Casting a prosthesis on a refractory model. This method has some advantages over the first, since there is no shrinkage of the metal and the possibility of modifying the workpiece from wax is eliminated when it is removed from the model and packed into a refractory mass.
Let's consider in more detail the stages of manufacturing a clasp prosthesis on a refractory model. This process is very important for obtaining a quality product.
Obtaining a design on the
refractory model. The laboratory steps for making a clasp prosthesis include an important point - impression making. The initial gypsum model plays an enormous role in obtaining the casting of the prosthesis frame( to make it all exactly up to a millimeter).
If the prosthesis is prepared on a refractory model, then make two copies of the workers and one additional. In the manufacture of prostheses immediately on two jaws receive four, that is on two from each jaw. This is done so that one model can be used for examination with subsequent copying, and the second one is used to make a base with rollers, to determine occlusion, grafting and the final manufacture of the prosthesis.
The working model plays a huge role in obtaining a high-quality prosthesis, therefore the specialist must constantly keep under control clinical and laboratory stages of manufacturing of clasp prostheses.
Models of jaws should be as strong as possible so that they do not undergo abrasion, so parts that are particularly pressure-sensitive and loaded are made of super-gypsum, metal, cement or amalgam.
If in the course of work a defect in the working model is detected, then the mold must be altered.
Clinical stages of manufacturing of denture prosthesis
In the process of manufacturing prostheses clinical stages are several:
- The first stage begins with examination of the patient, talking with him, setting an accurate diagnosis, choosing the pathology treatment tactics. Also, the doctor will remove the molds for the preparation of diagnostic and auxiliary models.
- At the second clinical stage, the occlusion of the jaws is determined, the diagnostic model is examined in a parallelometer, after which a drawing of the foundation of the future prosthesis is applied to it. It is important to prepare the supporting teeth in order to obtain the mold for the prosthesis as precisely as possible.
- At the next stage, based on the diagnostic model, the boundary line and the skeleton of the prosthesis are applied using a parallelometer on the working model.
- In the fourth clinical stage, the metal frame is filled in the oral cavity. It is necessary to pay attention, that the skeleton did not have sharp edges and defects. The saddle base and the arch should not come in contact with the mucous membrane of the oral cavity. Clammers should be close to the supporting teeth. The doctor looks closely and determines if there is a balance of the prosthesis and, if necessary, eliminates the supercontacts between the carcass and the antagonist teeth. Also at this stage there is a selection of artificial teeth.
- The construction check follows. It is necessary to make sure that the clinical and laboratory stages of manufacturing the clasp prosthesis are met, and it meets all the requirements both on the model and in the oral cavity of the patient.
- The last step is to put a prosthesis in the mouth, check the balance. The doctor must give advice on the care of the structure.
All these stages of making a clasp prosthesis on locks or clasps are mandatory. This is the only way to get a solid and reliable design.
Stages of manufacturing prostheses in the laboratory
Clasp prosthesis manufacturing stages have also laboratory, that's what activities are carried out on their length:
- The first stage is the casting of the diagnostic model and the auxiliary one. Manufacture of wax bases with occlusal ridges.
- The following is the production of the working model.
- Prepare for duplication. For this place, which should not come into contact with the oral mucosa, is insulated with a wax plate, and all voids are also filled with wax. Further, the model is fixed on a special ditch for duplication. A hot mass is placed in it and cooled until solidified. Then the model is removed and a refractory mass is poured into the mold. The prepared model is released from the duplicating mass, dried and a skeleton drawing of the future prosthesis is applied to it. Next, wax reproduction is modeled and replaced with a metal one.
- the next step is performed zagipsovku working and supporting models in the articulator and make the alignment of the artificial dental wax-based prosthesis.
- At the last stage, the wax base is changed to plastic. Also at the end of the polishing and polishing of the prosthesis is mandatory.
This may be considered that the clasp prosthesis stages of manufacture have all gone and are ready for installation.
Indications and contraindications
If you can not put the bridge, the doctor advises the patient to clasp prostheses to correct the defect. Usually this can not be avoided if there are not several teeth in a row and the supporting ones are preserved only on one side. Clasp dentures will also be needed in the following cases:
- If there are no anterior teeth.
- There is a defect in the dentition.
- There are no lower teeth.
- The patient has a deep bite.
- Bruxism is also an indication for the use of such prostheses.
- Periodontal disease.
Besides indications for their use, you can select the categorical prohibition of the use of clasp dentures:
- If you have an allergy to the metal structure.
- No teeth so that you can rely on them.
- The bottom of the lower jaw has insufficient depth.
- The remaining teeth have a low crown part.
- The sugar content in the blood is too high.
- There are oncological diseases.
- Pathology of the cardiovascular system.
- Inflammatory processes in the oral cavity.
- Diseases of the respiratory system.
Advantages and disadvantages of clasp dentures
Whatever design or used in prosthetics, they all have their pros and cons. The same applies to clasp prostheses. Here are the advantages they have:
- Compact and lightweight.
- Well fixed in the oral cavity.
- The pressure on the jaw is correctly distributed when chewing.
- If the prosthesis is fixed on the upper jaw, then the entire sky is not affected, which does not lead to a disruption in the pronunciation and deformation of the taste sensations.
- Perfectly suitable for the treatment of periodontal disease.
- Ease of care.
- Long term of use.
There are some dentures in the prosthesis:
- Some patients may have an allergy to the metal structure.
- I have to get used to them for a long time.
- To put them, you need at least a pair of your teeth.
- Atrophy of the dental bone is gradually occurring.
- Their cost is much higher if compared with plate or bridges.
Of course, there are more advantages to this method of prosthetics, but before installing it, you still need to weigh the pros and cons.
How to care for clasp dentures?
The sequence of clinico-laboratory stages of manufacturing of clasp prostheses is considered. If you follow them, the design will be strong and reliable. Despite the fact that clasp prostheses are distinguished by their longevity, some recommendations for care will prolong their life:
- Daily cleaning of the prosthesis, for this you can use a conventional toothbrush.
- It is advisable to process the oral cavity and prosthesis not only in the morning and in the evening, but after each meal.
- It is recommended to purchase special disinfecting tablets to care for the prosthesis.
- If you have the means, you can buy an ultrasonic bath for care.
- It is desirable to visit every six months a specialist who will professionally clean the prosthesis and restore, if necessary.
From these recommendations it becomes clear that care for clasp dentures is not at all complicated, but necessary, so that their wearing is not only comfortable, but also lasting.
With any pathology in the structure of the dental system, only a competent specialist will be able to assess the severity of the defect and choose the most optimal method of prosthetics.