Fixed Partial Dentures (Bridge)
Bridges are tooth replacements attached to adjoining natural teeth. They are best for people with a few missing teeth, either the front or the back teeth. To replace missing teeth with a bridge the adjoining teeth must be healthy and have good root and gum support.
The two common types of bridges are the fixed bridges and the bonded (Maryland) bridges.
Conventional Fixed Bridge
The bridge can be made either in metal, Porcelain fused to metal or all porcelain, depending on the esthetic requirements of the patient and the amount of load it will be subjected to. In a conventional bridge one or more artificial teeth are set between crowns placed over adjoining natural teeth. The dentist shapes the natural teeth to receive the crowns. This procedure normally takes two to three visits to be completed.
Advantages
- It has a long life
- Easy to Clean
- Improves the bite
- Improves esthetics
Helps prevent movement of adjacent and opposing teeth
Disadvantages
- More tooth reduction required than for a resin bonded bridge
- May be difficult to make it look natural in cases of excess bone or gum loss
Bonded Fixed Bridge
A bonded bridge consists of one or more artificial teeth between metal wings. The anchor teeth are reshaped slightly, and the wings are bonded to them using resin cement.
Advantages
- Requires less tooth reduction than conventional bridge
- Does not require full crowns on either side of the missing teeth
- Costs less than a conventional bridge
Disadvantages
- May not last as long as a conventional bridge
- Less ability to alter shape and size of teeth
- Metal backing may show if teeth are thin
- Gum can shrink around teeth, leaving empty spaces
Removable prostheses( Dentures)
A denture is a set of removable artificial teeth that rest directly on the gums and may be attached to adjoining teeth using clasps. Dentures are usually made with gum coloured acrylic resin to which artificial teeth are attached. Dentures are advised for patients who have a number of teeth missing and in whom fixed partial dentures cannot be given
Dentures are usually of four types-
- Removable partial dentures
- Over dentures
- Immediate Dentures
- Complete dentures
Removable Partial Dentures
Removable partial dentures are usually given to patients who have a number of teeth missing and where fixed partial dentures are not recommended. They usually consist of replacement teeth attached to gum colored plastic bases, which are connected by a metal framework. Removable partial dentures attach to natural teeth with the help of metal clasps or devices called precision attachments, which are more esthetic than clasps. Crowns may be required on the natural teeth as they improve the fit of removable partial dentures.
In our country the plastic removable dentures are used widely, because they are cheaper than the dentures with the metal frameworks, however in the long term these dentures can cause harm to the adjacent teeth.
Advantages
- Less expensive than fixed bridges
- Prevents movement of adjacent and opposing teeth
- Helps to increase chewing efficiency by replacing missing teeth
Disadvantages
- If partial denture is not designed properly it can cause damage to supporting teeth, especially the plastic dentures.
- May not be as esthetic as a fixed bridge
- Takes more time to get adjusted to than a bridge
Overdentures
An overdenture is a removable denture designed for patients who have a number of teeth missing in the mouth, but have a few good teeth remaining. The best scenario being when there are canines and one posterior tooth remaining in each side of the mouth. These teeth are root canaled, i.e. the pulp (contains blood vessels and nerves) is removed from the teeth, and the canals are filled with an inert material. The teeth are reduced in height and the dentures are constructed over these teeth. In some cases attachments may be placed over the teeth to increase the retention of the dentures.
The denture is usually made with gum coloured acrylic resin , with the artificial teeth attached to it. Although this form of treatment is more expensive than conventional dentures, it has a number of advantages like better tactile sensation and better chewing efficiency.
Advantages
- Saves roots, which in turn reduces bone loss
- Improves chewing efficiency
- Ridge subjected to less stress
- Allows patient to retain some tactile sensation
- Better retention and fit as compared to complete denture
Disadvantages
- Attachments can break
- Costlier than conventional dentures
- Bulkier than removable partial dentures
Immediate Dentures
In a few cases , patients may have to undergo extraction of all their remaining teeth, i.e. advanced gum disease. Here it is advisable to get an immediate denture done. The main advantage is that the patient is never without teeth.
The procedure involves extracting the patients remaining back teeth and waiting for a period of about ten days for healing to occur. The patient is then called in to make the necessary records. The lab then fabricates a complete denture that duplicates the appearance of the natural teeth or altered if the patient so desires. At the next appointment the front teeth are extracted and the immediate dentures inserted. After about a month the gums will shrink, the dentures need to be relined at this stage or new dentures fabricated.
Advantages
- Patient is not seen without teeth
- Helps protect the gums during the healing phase
Disadvantages
- Denture requires relining or may have to be remade
- May require more adjustments than a conventional denture
Complete Denture
Complete dentures are made of gum colored acrylic with artificial teeth attached to them and they rest completely on the gums. Complete dentures are able to maintain or recreate lip and cheek support and restore the patients smile.
Advantages
- Supports lips and cheeks
- Improves speech
- Less expensive than over dentures
Disadvantages
- Less chewing efficiency than over dentures or removable partial dentures.
- Lower denture may be loose if bone has shrunk a lot
- May impede speech in some patients