Overdenture

[3] An overdenture is usually used for elderly patients that have lost some teeth but not all, rendering them suitable for a set of full dentures.

Frequently, elective root canal treatment and coronal modification are carried out on the teeth that are used as abutments.

This means that the pulpal tissues and crowns of the natural teeth are removed, followed by contouring of the tooth structure above the gum.

The teeth selected to provide support should be healthy i.e. not decayed and no/ manageable gum disease, thus ensuring long term retention in the jaw.

Most of the time, the crown of the abutment teeth has to be removed to allow space for placement of overdenture without interfering the bite.

Implant-supported Edentulous patients with sufficient amount of bony ridge on their jaws can opt for implant supported overdenture.

Overall, this is the most popular attachment system due to its ability to stabilise overdenture and relatively higher wear resistance.

[2] Preventative Dentistry - The use of an overdenture delays the process of leaving the patient completely edentulous and assists in the preservation of bone.

[2] - As a main priority for many dentists and patients, preventative dentistry is a reason for prescribing an overdenture as it retains the natural teeth for longer.

[17] - Patients who have unfavourable tongue positions and muscle attachment for a conventional removable prosthesis could find that an overdenture has increased retention and stability.

Mandibular bone loss was examined by Crum and Rooney 1978 in patients with immediate complete dentures and in those with immediate overdentures on two lower canines.

They found over the five years after placement 0.6mm bone loss in the overdenture group and 5.2 mm in the immediate complete dentures in the anterior part of the mandible.

This reduction in bone loss enables increased stability and retention of the overdenture which has psychological and functional advantages for the patient.

[19] Preservation of the alveolar ridge, especially with a lower prosthesis may improve patients comfort, chewing, phonetics and aesthetics allowing a better quality of life.

[20] Plaque build up around overdenture abutments or precision attachments can lead to inflammation and hyperplasia of the gingiva.

As a result, gingival recession may occur leading to exposure of the root surfaces to the oral environment.

A study which looked at patients wearing overdentures found that the rate of tooth loss was in the order of 20% and was most commonly due to periodontal disease.

[20] It is important to encourage patients to use a fluoride containing toothpaste over the denture abutments to minimise tooth surface loss and risk further infection.