Cast Partial denture

Overview

A denture is a removable plate or frame that retains prosthetic teeth to replace lost teeth. Cast partial dentures are for adults over the age of 65 who are missing many teeth. The patient can remove and replace these dentures. Removable partial dentures with cast metal frames provide a number of benefits over traditional partial dentures. The frames of these dentures are custom-made to match the teeth. Because they sit on and are attached to the teeth, they are extraordinarily stable and retentive.

 

What is Cast partial denture?

A denture is a removable plate or frame that holds one or more artificial teeth to replace lost teeth in the mouth. A Cast Partial Denture (CPD) is a removable partial denture made of a cast metal framework with prosthetic teeth fixed in acrylic resin. Cast Partial Denture is stronger, more lasting, and more retentive than traditional acrylic dentures. However, the production of a cast partial denture is more expensive, time-consuming, and intricate than that of traditional acrylic dentures. Each denture is custom designed and manufactured for each patient. These are metal and plastic partial dentures. The skeleton (main connection) and hooks used to secure the denture are made of metal, whereas the visible sections and teeth are made of plastic. Plastic-only dentures feature a denture plate that covers the whole palate of the upper jaw or the region beneath the tongue of the lower jaw, producing pain, a sense of a foreign body in the mouth, and a diminution in taste, heat, and cold sensations. This plate is replaced with a metal connection in cast partial dentures. As a result, the denture skeleton is quite sturdy. This allows for a size decrease, which provides comfort and eliminates the sensation that the denture is overly large. The flavor and temperature of the dish are both near to normal.

Patients easily adapt to this style of the denture, but they are more difficult to make and cost more. They can be utilized in any tooth deficiency when there are enough healthy teeth to support the denture. This is required because they are very stable in the mouth and may only have minor movements. These motions are made possible by the fabrication of individually cast metal hooks that are commensurate with the form and properties of the individual's teeth. Cast partial denture designing is a sophisticated procedure that must fulfill numerous requirements, including accurate transfer of masticatory pressure on accessible teeth and restoration of optimum speech and aesthetics.

 

What are the Indications for a Cast partial denture?

Because there are numerous methods for preserving a natural dentition, including the use of solitary crowns and fixed partial dentures, sometimes on dental implants, removable partial dentures are now primarily indicated in patients who have complaints about missing teeth in the aesthetic zone that cannot be resolved in another way. A removable partial denture is also indicated in patients with severely reduced dentitions or large or multiple edentulous areas, patients with severe periodontitis or excessive loss of alveolar bone, patients who are physically or emotionally vulnerable, as an interim solution on the way to edentulousness, as a temporary solution while waiting for more extensive treatment, and in patients who cannot afford an alternative.

The indications for a cast partial denture include:

• Partially missing teeth (lose some of the teeth)
• There are no teeth behind the edentulous area.
• Older than 17 years old
• The remaining teeth have good periodontal (gum) health.
• The patient wishes
• Injury to the jaw bone
• When it is necessary to support the remaining teeth against lateral and anterior-posterior forces

 

What are the Contraindications for a Cast partial denture?

• Oral hygiene issues
• Aesthetically unappealing region (especially front teeth area)
• Arch tooth weakness
• The remaining teeth are unable to support the detachable prosthesis (dentures)
• Caries are rife.
• Periodontal/gum disease

 

What are the clinical steps in Manufacturing a Cast partial denture?

Cast partial denture fabrication necessitates many dental appointments. Based on particular dental problems, each denture is uniquely designed and produced. What to expect during your dentist sessions with cast partial dentures:

• First visit

 During the first dental appointment, dental impressions for both the upper and lower dental arches will be taken. The study models are created. On the research models, Cast Partial Dentures are specifically created.

Impressions are obtained from the upper and lower jaws, and the central occlusion is calculated using the existing teeth. The dental technician molds gypsum replicas of the jaws and places them in the right ratio (to achieve central occlusion). Individual imprint spoons are created at this step, and the denture's major analysis is conducted. The insertion and removal direction of the denture, the supporting teeth, their retention locations that will act as retention hooks, and the kind are all determined here.

• Second visit

The dentist will undertake a treatment known as mouth preparation during the second dental visit. Mouth preparation is changing the contour of particular teeth in order to maintain and stabilize the final cast partial denture. Following mouth preparation, final dental impressions will be obtained. The master models are created. A dental technician designs and fabricates the metal framework of a cast partial denture in a dental laboratory. 

New imprints are made using unique spoons and a specific silicone substance to create working models on which the metal skeleton and hooks will be assembled. Occlusal templates with shafts are also produced.

• Third visit

The metal framework of a cast partial denture is tested in the patient's mouth at the third dental session to ensure proper fit and retention. A little modification to the metal structure may be required for improved fit and retention. The dentist will now document the patient's bite/occlusion. This is referred to as bite registration. The dentist will next choose the color of the artificial teeth depending on the patient's natural tooth shade. The dental technician will place the fake teeth on the trial dentures based on the patient's bite/occlusion.

• Fourth visit

Trial dentures are tried in the patient's mouth at the fourth dental visit. The trial denture's fit, stability, retention, phonetics, and aesthetic are all tested and changed as needed. Following the try-in, the trial dentures will be submitted to a dental laboratory for final cast partial denture manufacture.

• Fifth visit

The final cast partial dentures are inserted into the patient's mouth during the fifth dental session. The final cast partial dentures are checked and corrected for fit, stability, retention, phonetics, and aesthetics. The patient's occlusion/bite is evaluated and modified as needed. The patient is instructed on proper denture maintenance.

• Sixth visit

In the sixth dental visit, the patient is called for a denture review after one week following denture insertion. The patient will be asked if the dentures are causing any problems (like discomfort, pain, or ulcers).

The fit, stability, retention, phonetics, and aesthetics of the cast partial dentures are all examined and changed as needed.

The patient's occlusion/bite is evaluated and modified as needed.

• Future dental visits 

If the cast partial denture is causing the patient any problems, the patient should notify the dentist and schedule a dental appointment for a check-up.

 

What are the Benefits of using a Cast Partial Denture?

• Reduces tissue change, reduces the need for denture relining or rebasing.
• Occlusal (biting stress) distribution is excellent.
• The movement of the denture bases massages the underlying bone and soft tissue.
• When compared to a traditional acrylic denture, it requires less direct retention.
• Occlusion must be balanced (bite), lips and cheeks should be supported.
• The tipping tension on the teeth is eliminated, stopping the teeth from moving.
• Patient comfort. Because cast partial dentures are thin, the thickness required for resistance in resin base materials is reduced. The decreased thickness offers more feeling, while the metal's flexibility softens the impact of the chewing forces. From the first day, the patient finds it easy to use and does not encounter any issues due to stiff foundation materials.
• Durability. These restorations are extremely resistant to compressive and bending stresses and do not degrade chemically when exposed to liquids, microorganisms, and the chemical environment of the mouth. It is more biocompatible.
• Function for relieving stress. The pressures acting on the edentulous ridge and supporting teeth are significantly decreased. Longer life expectancy.
• Resistance has increased, and stability has been improved.

 

What are the Disadvantages of using a Cast partial denture?

• Because of the inclusion of a cast metal framework, cast partial dentures become weighty and irritating to the patient.
• Repair is impossible, it is brittle.
• The fabrication process is complicated.
• Cast partial denture production requires more dental appointments and takes longer.
• Costly.
• Inability to avert harmful lateral stresses.
• It must be constantly maintained.
• You must become acclimated to wearing partial dentures.
• Plaque accumulation around abutment teeth can be increased with partial dentures, resulting in tooth damage and gum disease.
• The pressure and movement of the partial may cause harm to the abutment teeth as well as the gums.
• A replacement partial may be required if an abutment tooth is lost.
• Partial dentures may not be as effective as a permanent bridge or dental implant.
• At night, they must be removed.
• Aesthetically, it's not appealing.

 

Cast partial denture vs. Conventional acrylic denture comparison

• When compared to acrylic dentures, cast partial dentures are more sanitary and comfortable.
• Acrylic dentures are less costly than cast partial dentures.
• Cast partial dentures outperform acrylic dentures in terms of strength.
• Acrylic dentures are less difficult to make than cast partial dentures.
• If a cast partial denture is not built and cleaned properly, it can cause gum tissue damage surrounding natural teeth.
• Cast partial dentures are typically superior to acrylic dentures in the long run.

 

What are the Alternative Treatments for Cast partial denture?

• Implant Dental
• Acrylic Dental Bridge Denture
• Each treatment method has its own set of indications and contraindications; therefore, it is essential to consult with your dentist to choose the best treatment choice for you.

Natural teeth are always superior to artificial teeth. Thus, it is critical to avoid tooth loss in the first place by practicing basic dental hygiene on a regular basis. Daily tooth brushing, flossing, mouthwash usage, tongue cleansing, and regular dentist visits can all help to maintain good oral health. Remember that proper dental health care can lead to better overall health.

 

What is the Design of a Cast partial denture?

Dentists employed four different types of clasps for four distinct groups of Kennedy classification:

• Kennedy Class I

These are intended for persons who have an edentulous posterior, which means they are missing part or all of their teeth on both sides of their mouth. This needs to replace the lost posterior teeth and attaches to the remaining anterior teeth via a clasp.

Bilateral posterior edentulous regions in Kennedy Class I. The main retention is attached to the teeth closest to the problem. The clasp type "G" was employed, and the indirect retainer was positioned on the palatal surfaces of the frontal teeth. The objective is to keep the denture base as close to the alveolar ridge as possible when eating sticky food.

• Kennedy Class II

Class II partial dentures are ideal for those who are missing one or more posterior teeth on one side. The appropriate partial denture is attached to the teeth in the front of the mouth and the remaining teeth on one side. Both Class I and Class II include tooth loss at the rear of the mouth and rely on the front teeth for proper placement.

The unilateral posterior edentulous region in Kennedy Class II. The primary retention is placed on the teeth near the defect with clasp type "G," and the secondary retention is placed on the molars of the other half with Bonville clasps. A clasp at the first premolar on the opposite side of the defect is employed as an indirect retainer in this scenario.

• Class III Kennedy

The third kind of partial denture is for those who are partly edentulous and have missing teeth with adjacent teeth behind and in front of them. However, unlike the other denture categorization profiles, Class III may only connect to teeth and not tissue or gum. Because of this distinction, Kennedy Class III is the most secure of the designs.

Unilateral or bilateral posterior edentulous area(s) bordered by surviving teeth In these circumstances, we used clasps of the type "E." In this scenario, the occlusal clasps put on the distal teeth are employed as indirect retainers to assist maintain the denture.

• Class IV Kennedy

Unlike the preceding three groups, Class IV is the least prevalent and involves only one edentulous region. There is one anterior edentulous region. Clasps type "E" are utilized as the main retention at the first premolars (distally to the defect), whereas Bonwille clasps are used as indirect retainers at the molars on both sides.

Parts of a Cast partial denture

Because each categorization comprises various traits, each will have its own set of specifics to guarantee that the cast partial denture fits securely and is tailored to the patient's mouth. In general, any cast partial denture contains the saddle, direct retainers, indirect retainers, connectors, and incisal and occlusal rests. Each of these components contributes to the efficient operation of the denture within the mouth.

• The Saddle

The saddle, or base, contains the prosthetic teeth that will be implanted over the slightly edentulous region known as the saddle area by dentists. These saddles may be supported by the teeth or mouth tissue. If the edentulous area, or area with missing teeth, lacks a terminal tooth to connect to, this base can be modified, and the dentist may instead utilize a distal extensions base.

• Retainers

To achieve a solid attachment to the gum tissue, direct retainers rely on abutment teeth. Clasps and other precise attachments are examples of this. Each clasp will have a reciprocal arm, a retentive arm, and an occlusal rest to help attach the removable partial denture to the teeth. However, there are various clasps to pick from, each designed to fit a certain situation. There are three types of clasps: wrought clasps, infrabulge clasps (also known as bar clasps), and cast circumferential clasps (suprabulge clasps.) The indirect retainers, on the other hand, employ modest connections and rests to stabilize the denture saddle within the mouth.

• Connectors

There are major and minor connectors for a detachable partial denture. The primary connector connects one side of the arch to the other and is the unit to which all other components are either directly or indirectly attached. For the bottom region of the mouth, there are six primary connection types: palatal bar, palatal strap, palatal plate, U-shaped, total palatal coverage, and anteroposterior designs. Similarly, six primary connector designs may be found in the upper half of the mouth: lingual bar, lingual bar with an indirect retainer, lingual plate, sublingual bar, cingulum bar, or labial bar/plate. The minor connection, on the other hand, connects the major connector to other denture components such as clasps and occlusal rests.

• Occlusal rest

An occlusal rest is a hard extension in the denture form that is inserted in rest seats to assist maintain the overall structure of the partial denture. A rest is any denture component that offers vertical support, and a rest seat is any prepared abutment surface designed to accept the rest. 

 

Conclusion

Cast partial dentures, like other dental surgeries, have pros and cons. Overall, cast partial dentures are less expensive and need significantly less intrusive procedures to be fitted than other choices when a patient has several missing teeth. Depending on the state of your teeth, your dentist may be able to customize the dentures to incorporate additional teeth over time. This makes cast partial dentures an appealing alternative for those who are experiencing persistent tooth loss.