When it comes to replacing teeth, a patient has several options. These options are listed below along with a description of the procedure and the advantages and disadvantages of each procedure.
Dental Implants: From years of research in biomaterials and surgical technique, dental implants have become the state of the art method for replacing teeth. A dental implant is a titanium cylinder that is inserted into the dental ridge (alveolar bone) of the jaws. The cylinder becomes fused to the bone over time in a process known as osseointegration. This process normally takes about 6 months in the upper jaw (maxilla) and three months in the lower jaw (mandible). Once osseointegration has occurred, dental implants can be used as anchors for individual teeth, bridges, and partial or full dentures. Click here to see illustrations and actual cases which demonstrate the ways in which dental implants can be used:
The main disadvantage of dental implants is the amount of time it takes to complete dental implant treatment. Treatment time can range between four months and nine months. If a reconstructive surgery such as bone grafting is required prior to implant placement, this process may take longer. Click here to see an illustration of one type of bone grafting procedure that is commonly performed in conjunction with the placement of dental implants:
There are many advantages, however, to choosing dental implants over traditional methods of tooth replacement. Placing dental implants is a true reconstructive procedure. In most cases, when teeth are lost, the surrounding bone shrinks down (atrophy). In severe cases of atrophy of the jawbones, dramatic changes in facial appearance can occur. Placing dental implants is the only method of tooth replacement that helps preserve surrounding bone.
Furthermore, when used to replace individual teeth, dental implants can stand alone and do not require the preparation of natural teeth for support. For patients who wear removable partial or full dentures, implants can be used as stable anchors to help prevent displacement of these removable devices.
The latest studies show that over 90% of dental implants placed remain in service after fifteen years. Longetivity of dental implants depends upon a patient’s overall health and how well the implants are cleaned and maintained.
Bridge: If supporting teeth exist on either side where teeth need to be replaced, then a bridge is one option for tooth replacement. A bridge is made by preparing or shaving down at least one tooth on either side where a tooth or teeth are missing. These teeth are crowned and a metal substructure connects the teeth on either side. This metal substructure can be fabricated in the form of teeth or porcelain may be fused to the metal to create the appearance of teeth. The advantage of this procedure is the relatively short time in which a bridge can be made. It usually takes about 2 to 3 weeks. Disadvantages include the necessity to prepare the teeth on either side especially if these teeth are totally intact. Furthermore, cleaning around a bridge may be difficult. Complaints of food getting stuck under the bridge are not uncommon. Floss has to be threaded under the bridge for proper cleaning which is often difficult and therefore not regularly performed by patients. If a bridge fails it will be due to fracture, recurrent decay, or periodontal disease involving the supporting teeth. This may lead to having to perform further procedures on the supporting teeth, such as root canals, or removal of the supporting teeth themselves
Bonded Bridges: In certain situations a false tooth may be bonded to adjacent teeth to fill an empty space. This is known as a bonded bridge or Maryland bridge. This is an option for replacing incisor teeth. Due to the greater forces of chewing in the premolar and molar areas, bonded bridges are generally not indicated for replacement of premolars or molars. While bonded bridges require minimal preparation of adjacent teeth, the advantages and disadvantages are similar to fixed bridges.
Removable Partial Dentures: For multiple missing teeth a removable denture may be worn. Partial dentures rely on existing teeth for support; therefore, some preparation of existing teeth is necessary. Some parts of the partial denture may rest on the dental ridges where teeth are missing. The advantage of partial dentures is the relatively short time in which teeth can be replaced using this method. However, wearing a removable appliance is objectionable to many patients. Furthermore, patients may find it difficult to chew while wearing a partial denture. Because partial dentures rely on teeth for support, early wear or loss of these teeth may occur due to excess forces applied to the teeth. Pressure applied to the alveolar ridges may cause accelerated atrophy of bone.
Full Dentures: When a patient loses all the teeth in either the upper or lower arch a full removable denture is usually worn. One advantage is that a denture can be fabricated to immediately replace teeth if they need to be removed. However, this results in a major adjustment to function such as chewing and speaking. A patient also has to adjust psychologically due to the possibility that the denture may become displaced during function. Furthermore, pressure applied to the alveolar ridges may cause accelerated atrophy of the jaw bones. In fact, in severe cases of atrophy, a denture may not fit at all due to the loss of supporting structures. This may lead to having to perform reconstructive procedures such as bone graft reconstruction of the jaw bones.