OVER DENTURE

Dentures are removable dental appliances designed to replace some or all of the teeth in a dental arch. Dentists found that by attaching the denture to either the remaining teeth in the mouth or to dental implants, they could better stabilize it. This appliance is called an "overdenture".

Over time, denture wearers also generally experience significant bone loss in the jaw. One major difference between the two systems is that an overdenture can be taken out for cleaning at home, while a fixed denture is designed to stay in your mouth permanently

Types of Abutment

Tooth-supported

This type of overdenture overlies natural tooth structures. 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. This allows even distribution of occlusal stress onto the abutment teeth and soft tissues. Other than that, retention of natural teeth in the jaw helps preserve bone by delaying the process of bone resorption in the jaw.

Selection of abutment teeth depends on a few factors including:

Location

To provide adequate support, there should be one abutment tooth per quadrant and the abutment should ideally be a canine.

Prognosis

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.

Feasibility of endodontic treatment

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. Therefore, the pulp has to be removed. If the root canals of the abutment teeth are obliterated, endodontic treatment is not required. Teeth with non-negotiable root canals should not be selected as abutments.

Implant-supported

Edentulous patients with sufficient amount of bony ridge on their jaws can opt for implant supported overdenture. This type of over denture gains support from both the dental implants and intraoral tissues. Having implant-supported overdenture provides better stability of prosthesis and reduce bone resorption. However, a conventional complete denture can be considered as an alternative due to less treatment time needed