Prosthodontics

Porcelain crowns are a permanent prosthodontic replenishment secured on adequately ground teeth – both live and dead. They are usually used when the tooth is heavily damaged, and a composite material reconstruction isn’t possible or wouldn’t be strong enough. Crowns strengthen the endodonticly treated teeth, make them more aesthetically pleasing and allow for an occlusion reconstruction. They are also used with implants. It takes about 7 days to prepare and crown a tooth. It is possible to prepare a temporary crown for this period during the same visit.

Prosthetic bridges are used to replenish lost teeth. Crowns are placed on the teeth adjacent to the lost tooth, which conjoined form a bridge, permanently filling the space of a lost tooth. They can be made of different materials (porcelain or composite with a metal framework). It isn’t always possible to use a bridge – the dentist needs to assess the situation. An alternative to a bridge is an implant, which doesn’t require patient’s own teeth to be ground.

Crowns and bridges are made of two layers: the exterior – aesthetic (made out of porcelain) and interior – structural, which is made out of one of the materials listed below. The properties of the structural material affect the final aesthetic and durability of the end product. The materials used for structural support can be metal, gold or zircon.

Metal is the cheapest, most basic material. Its use requires a thorough medical history, because the patient may be allergic to certain components of the alloy. It has a grey color, which may negatively impact the crown aesthetic near the gum, and a dark border may appear on the point of contact with the gum.

Gold is fully safe for the patient. It has bacteriostatic properties (creates an environment unfriendly for the bacteria). Gold is a material, which allows for a higher precision of preparation, and therefore leakproofness of the tooth. These advantages of gold significantly increase the durability of the restoration and the health of paradentiun (gum around the tooth).

Zircon is the most advanced material prepared with digital technology. It allows for the highest possible accuracy and leakproofness. It is a fully safe, biocompatible material which doesn’t cause allergies. Its biggest advantage is that the whole crown is one element, which is white and translucent, which causes the porcelain onlay to reflect light exactly the same way real teeth do. It allows for the most accurate, natural appearance of a tooth.

Another prosthodontic solution is a veneer. A veneer is a thin piece of strong, durable porcelain attached to the front of a tooth. It allows for a small correction of the shape of a tooth, its “whitening” (it covers the natural color of a tooth) and elimination of gaps between teeth.

It’s undistinguishable from a real tooth, and the procedure is painless. Contraindications for a veneers include too short teeth (with not enough area to attach the veneer to), bad habits (such as biting one’s nails, which can potentially lead to unsticking of the veneer) and inadequate oral hygiene.

When a tooth is too damaged for a veneer to be attached, a prosthetic crown is used.

At Denta-line we offer inlay and onlay prosthetic restorations as an alternative to the composite fillings. They are made out of porcelain or composite materials, they strengthen the tooth, are durable (up to 10-15 years) and resistant to abrasion. They allow for filling of even big cavities and involve them in the process of chewing again.

When a tooth is severely weakened (e.g. after endodontics) and damaged, a crown and root insert can be used. It is made of two parts – root, cemented in the root of a tooth which becomes a foundation for the second part, the crown. The material used is picked by the dentist depending on the individual needs of a Patient.

Acrylic denture is not the best solution, because unlike a frame denture it affects all of mucosa it covers, which causes more bone loss than a frame denture, and is therefore less beneficial for the gums and remaining teeth.

Partial acrylic denture is a kind of prosthodontic restoration where both the plate and the teeth are made of acrylic. It is an alternative when the conditions of don’t allow for a different kind of a denture, e.g. frame denture, or the Patient can’t afford a different type of dentures.

The upper denture covers the palate completely (unlike a frame denture, which only covers a small part), which causes some discomfort at the begging.

Complete acrylic denture is a denture that restores teeth in case of total tooth absence (anodontia). It is a denture made exclusively of acrylic, which makes it the most beneficial for the mucosa and the crestal bone. The forces exerted during the chewing of the foods are transferred through the denture plate onto the entire crestal bone and the mucosa the covers it. A complete denture requires a lot of work and engagement from the Patient in order to make the usage easier. The Patient has to get used to that denture and most importantly, learn to use it.

For the Patients who are allergic to acrylic we use an antiallergenic material. The waiting period for preparation of a denture is 7 to 14 days. The waiting period for a temporary denture is about 12 hours – they are usually used after big extractions of a Patient’s teeth.

Frame dentures are dentures that replenish partial teeth deficits which for various reasons don’t qualify for a bridge. They are metal-acrylic dentures. The base is made entirely of molded metal, perfectly matching the shape of the Patient’s mouth floor. Therefore the palate plate is significantly smaller than in an acrylic denture than in a partial gum denture, which increases the comfort of use. Additionally the metal frame has metal protrusions leaning on chewing surfaces which creates a physiological distribution of the chewing forces onto the mucosa and the crestal bone. In other words, the forces pass through the teeth and not the mucosa, which doesn’t lead to sagging of the denture – an unfavorable outcome.

The frame dentures are supported by metal brackets. They are springy which allows for better fixture to the teeth, and so they don’t fall of when eating. They aren’t very aesthetic, but can be substituted with more precise mounting elements such as brackets and bolts. Crowning of surrounding teeth is necessary for these which results in better aesthetic and higher comfort of use, but increase the cost.

The dentures also stabilize swaying teeth. The brackets can be more complex to hold the teeth and eliminate excessive movements to the sides and front-to-back. They slow down, or sometimes even stop the tooth loss caused by periodontitis. These brackets are made of metal, but are placed behind the teeth, making them invisible during the usage of the denture.

In case of a loss of a Patient’s own tooth it is possible to add it to the denture, allowing for its continued usage. There are no counter-indications to the usage of frame dentures. They are the best prosthodontic filling out of all removable dentures. Frame dentures are durable, don’t break or crack, and the metal allows for more longevity while maintaining smaller dimensions.

Nylon dentures ae the newest solution of prosthodontics. These dentures are a great alternative to the traditional complete and partial acrylic dentures. They are made out of a special elastic material, which is resistant to breaking and significantly increases the comfort of use. In comparison to the traditional acrylic dentures they have many advantages:

• They are thinner
• They hold better
• They don’t cause allergic reactions
• They don’t have metal brackets, instead they have elastic, gum-colored brackets
• They are light and elastic – they don’t break or crack
• They take up less space in the mouth
• Nylon is very transparent, and so they look very good on the gums of the patient