Implant Overdenture
An implant-retained overdenture is a removable dental prosthesis that is supported by the residual oral tissues and employs dental implants for retention. Because they are simple, cost-effective, and less invasive, overdentures are an alternative for those edentulous patients who are not satisfied with conventional dentures.
Overdentures are indicated when patients are not satisfied with the stability and retention of the conventional removable denture but also do not complain about pain and discomfort of the mucosa.
Overdentures are considered a simple, cost-effective, viable, less invasive and successful treatment option for edentulous patients.
Implant overdentures are designed to be removable by the patient for hygiene. This restoration can be designed with three different types:
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- Implant bar with locators
- Implant bar with hader clips
- Straight to the implant using attachments such as locators and o-ring attachments.
Metal reinforcement of denture base is available
An implant-retained overdenture is a removable dental prosthesis that is supported by the residual oral tissues and employs dental implants for retention. Implant-retained overdentures are a treatment alternative for many patients for whom conventional dentures are poorly tolerated. They may be indicated in patients with changed anatomy, neuromuscular disorders, significant gag reflexes, or considerable ridge resorption. Implant retained overdentures may reduce residual ridge resorption and enhance mastication and hence nutritional status, as well as improve speech and patient self-esteem.
The patient gains several advantages with an implant-supported overdenture prosthesis. The complete mandibular denture often moves during mandibular jaw movements during function and speech. A mandibular denture may move 10 mm during function. Under these conditions, specific occlusal contacts and the control of masticatory forces are nearly impossible. An implant overdenture provides improved retention and stability of the prosthesis, and the patient is able consistently to reproduce a determined centric occlusion.
Validations
Bone Loss
The use of dental implants to provide support for an implant overdenture offers many advantages compared with the use of removable soft tissue–borne restorations. A primary reason to consider dental implants to replace missing teeth is the maintenance of alveolar bone. The most common position to insert implants for an overdenture is in the anterior mandible. After the implants are inserted, the anterior bone under an overdenture may resorb as little as 0.6 mm vertically over 5 years, and long-term resorption may remain at less than 0.05 mm per year.[1, 2] Stress and strain may be applied to the bone surrounding the implant. As a result, the decrease in trabeculation and volume of bone that occurs after tooth extraction is reversed. There is an increase in bone trabeculae and density when the dental implant is inserted and functioning. The overall volume of bone around the implants is also maintained. An endosteal implant can maintain bone width and height as long as the implant remains healthy.[3] As with a tooth, peri-implant bone loss may be measured in tenths of a millimeter and may represent a more than 20-fold decrease in lost bone structure compared with the resorption that occurs with removable prostheses
[1] Bergendal et al., Implant supported overdentures: a longitudinal prospective study, Int J Oral Maxillofac Implants 13:253–262, 1998.
[2] Attard et al., Long-term treatment outcomes in edentulous patients with implant overdentures, Int J Prosthodont 17:425–433, 2004.
[3] Roberts et al: Implants: bone physiology and metabolism, Calif Dent Assoc J 15:54–61, 1987.