Today, the achievements of science have moved far ahead. It is now quite possible to correct congenital or acquired defects of the dentoalveolar system. And this can be done not only in children, but also in adults. Let's try to figure out what clasp prostheses are, we will also consider the stages of manufacturing such structures.
Assignment of clasp prostheses
This type of prosthesis has excellent strength, so this design is used quite widely in dentistry:
- To eliminate defects in the teeth at the end of the dentition.
- For the treatment of pathologies of the lateral section.
- As removable dentures when replacing frontal teeth.
- For prosthetics of strongly loose teeth.
If a dentist recommends using clasp prostheses on attachments for orthopedic treatment, then 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 claspprosthesis?
If we consider clasp prostheses (the manufacturing steps will be described below), then they represent an arc consisting of three main parts:
- Die-cast metal frame.
- Gingiva simulation plastic base.
- Artificial teeth that are fixed on the base.
To make it possible to install such a prosthesis, you must have at least a couple of your own teeth, then the design can be securely fixed.
Varieties of clasp prostheses
To consider the laboratory stages of manufacturing a clasp prosthesis, you need to know what types of such designs are. They are most often classified according to the method of attachment in the oral cavity.
- Lock prosthesis on attachments. It is securely fixed on the abutment 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 an ideal option when you need to restore the dentition with the loss of several teeth. We will describe the stages of manufacturing a clasp prosthesis on attachments below.
- Clamp. The prosthesis has a clasp fastening and evenly distributes the load on the jaw. It is convenient to use as it is easy to pull out and put back in place.
- Telescopic. Prostheses on telescopic crowns are the most expensive. The work on their manufacture requires high precision and care. The main elements of the prosthesis are a cone-shaped base and a dental crown withcavity inside, ideally repeating the shape of the base. The base on which the structure is put on can be a turned tooth or an installed crown. This design provides a stable and secure fit.
The stages of making a clasp prosthesis on clasps are much less laborious. They are easier to make and are attached with small but strong hooks to existing teeth. But the disadvantage of this design is that when smiling or talking, the hooks can be noticeable. Prostheses on attachments look much more aesthetically pleasing. These are small locks, but they firmly and securely fix the prosthesis on the abutment teeth.
Recently, designs on telescopic dental crowns are gaining more and more popularity.
The stages of manufacturing a clasp prosthesis with locking require more painstaking work, which will certainly affect their cost.
What materials are clasp prostheses made of
All parts of prostheses are made using different materials. The frame can be metal or plastic. If plastic is used for the non-metal part, then steel or alloys are used for the metal part, for example, chrome-cob alt or gold-platinum.
Steel construction has its drawback - an oxide film is formed at the place of soldering. And this indicates that the process of solder oxidation in the oral cavity is underway. For this reason, steel parts are used less and less nowadays,most often preference is given to solid structures.
Technologies for obtaining a clasp prosthesis
Everyone should, of course, understand that such a complex structure can only be made in a dental laboratory. To do this, use various methods:
- Casting of the structure with the removal of the wax model from the workpiece. This technology involves the removal of a wax structure from a plaster model and its packaging in 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 one, as there is no shrinkage of the metal and the possibility of modifying the wax blank when it is removed from the model and packaged in a refractory mass is excluded.
Let's consider in more detail the stages of manufacturing a clasp prosthesis on a refractory model. This process is very important for a quality product.
Getting the design on the refractory model
Laboratory stages of manufacturing a clasp prosthesis include an important point - taking casts. The initial plaster model is of great importance for obtaining the casting of the prosthesis frame (so that everything is accurate to the millimeter).
If the prosthesis is prepared on a refractory model, then two casts of workers and one additional one are made. In the manufacture of prostheses for two jaws, four are obtained at once, that is, two from each jaw. This is done so that one model can be used for review with subsequent copying, and the second is used to make a base with rollers, to determineocclusion, casting and final fabrication of the prosthesis.
The working model is of great importance for obtaining a high-quality prosthesis, so the specialist must constantly control the clinical and laboratory stages of manufacturing clasp prostheses.
Models of the jaws must be as strong as possible so as not to be subjected to abrasion, therefore parts that are especially amenable to pressure, load are made of supergypsum, metal, cement or amalgam.
If a defect in the working model is detected during the work, then the cast will have to be redone.
Clinical stages of manufacturing clasp prostheses
There are several clinical stages in the process of manufacturing prostheses:
- The first stage begins with examining the patient, talking with him, making an accurate diagnosis, and choosing the tactics of treating pathology. The doctor will also take impressions 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 base of the future prosthesis is applied to it. It is important to prepare the supporting teeth in order to obtain the most accurate impression for the manufacture of the prosthesis.
- At the next stage, focusing on the diagnostic model, a boundary line and a drawing of the prosthesis frame are applied using a parallelometer on the working model.
- At the fourth clinical stagecarry out the fitting of the metal frame in the oral cavity. It is necessary to pay attention that the frame does not have sharp edges and defects. The saddle base and the arch should not come into contact with the oral mucosa. Clasps should tightly touch the abutment teeth. The doctor carefully looks and determines whether there is a balance of the prosthesis, and, if necessary, eliminates supercontacts between the framework and antagonist teeth. Also at this stage, a selection of artificial teeth is underway.
- Next comes the design check. It is necessary to make sure that the clinical and laboratory steps for the manufacture of the clasp prosthesis are observed, and that it meets all the requirements both on the model and in the patient's oral cavity.
- The last step is to put the prosthesis in the mouth, check the balance. The doctor necessarily gives recommendations on the care of the structure.
All these stages of manufacturing a clasp prosthesis on locks or clasps are mandatory. This is the only way to get a solid and reliable design.
Steps of making prostheses in the laboratory
Clasp prostheses manufacturing stages also have laboratory ones, here are the activities carried out during them:
- At the first stage, a diagnostic model and an auxiliary one are cast. Production of wax bases with occlusal rollers.
- Next is the production of the working model.
- Prepare for duplication. For this, places that should not come into contact with the oral mucosa are isolated with a plate ofwax, and all voids are also filled with wax. Next, the model is fixed on a special cuvette for duplication. The heated mass is placed in it and cooled until solidified. Then the model is removed and the refractory mass is poured into the resulting mold. The prepared model is freed from the duplicate mass, dried, and a drawing of the frame of the future prosthesis is applied to it. Next, the wax reproduction is modeled and replaced with a metal one.
- At the next stage, the working and auxiliary models are plastered into the articulator and the artificial teeth are placed on the wax basis of the prosthesis.
- At the last stage, the wax base is changed to plastic. Also, at the end, polishing and grinding of the prosthesis is required.
On this we can assume that the clasp prostheses have all passed the manufacturing stages and are ready for installation.
Indications and contraindications
If it is not possible to put a bridge, the doctor advises the patient to use clasp prostheses to correct the defect. Usually this cannot be avoided if there are no several teeth in a row and the abutments are preserved only on one side. Clasp dentures will also be needed in the following cases:
- If there are no front teeth.
- There is a defect in the dentition.
- Lower teeth missing.
- Patient has a deep bite.
- Bruxism is also an indication for the use of these prostheses.
- Periodontosis.
In addition to indications for their use, categoricalprohibitions on the use of clasp prostheses:
- If allergic to metal structure.
- No teeth to lean on.
- The bottom of the lower jaw is not deep enough.
- Remaining teeth have low crowns.
- Blood sugar too high.
- Have cancer.
- Pathologies of the cardiovascular system.
- Inflammatory processes in the oral cavity.
- Diseases of the respiratory system.
Advantages and disadvantages of clasp prostheses
Whatever designs are used in prosthetics, they all have their pros and cons. The same applies to clasp prostheses. Here are the benefits they have:
- Compact and lightweight.
- Good fixation in the mouth.
- The pressure on the jaw is correctly distributed when chewing.
- If the prosthesis is fixed on the upper jaw, then the entire palate is not affected, which does not lead to a violation of pronunciation and deformation of taste sensations.
- Great for treating periodontitis.
- Easy maintenance.
- Long life use.
The clasp dentures have their disadvantages:
- Some patients may be allergic to the metal structure.
- It will take a long time to get used to them.
- You need at least a pair of your own teeth to put them on.
- Gradually atrophy of the dentary occurs.
- Their cost is much higher when compared with lamellar orbridges.
Of course, there are many more advantages to this method of prosthetics, but before installation, you still need to weigh the pros and cons.
How to care for clasp dentures?
The sequence of clinical and laboratory stages of manufacturing clasp prostheses is considered. With their observance, the design will turn out to be strong and reliable. Despite the fact that clasp dentures are distinguished by their durability, some care recommendations will further extend their life:
- Clean your denture daily, you can use a regular toothbrush for this.
- It is desirable to treat the oral cavity and prosthesis not only in the morning and evening, but also after each meal.
- It is recommended to purchase special disinfectant tablets for denture care.
- If you have the funds, you can buy an ultrasonic care bath.
- It is advisable to visit a specialist once every six months, who will professionally clean the prosthesis and restore it, if necessary.
From these recommendations, it becomes clear that caring for clasp prostheses is not at all difficult, but necessary so that their wearing is not only comfortable, but also long-lasting.
With any pathologies 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.
