The concept of conventional tooth-retained overdentures is a simple and cost-effective treatment than the implant overdentures. When few firm teeth are present in an otherwise compromised dentition, they can be retained and used as abutments for overdenture fabrication. This helps improve the retention and stability of the final prosthesis significantly. It gives the patient the satisfaction of having prosthesis with his natural teeth still present.
Advantages of overdentures include preservation of alveolar bone, proprioception, enhanced stability and retention and maintenance of vertical dimension of occlusion Overdenture can be easily converted to complete denture over a period.
Disadvantages of overdenture include that meticulous oral hygiene is pertinent to prevent caries and periodontal disease. The over-denture tends to be bulkier and over contoured Encroachment of inter-occlusal distance is another disadvantage. This treatment modality is an expensive approach with frequent recall check-ups of the patient than a conventional removable complete denture. In overdenture treatment, the teeth are included as part of the residual ridge. The most important advantage is that the patient has the psychological benefit of having his own teeth which outweighs all the disadvantages state
Retentive devices included into denture teeth result in improved retention as well as support. An important periodontal requisite with over denture abutment is adequate zone of attached gingiva. Tooth-supported Overdenture treatment options are boundless and there are innumerable options to choose from for different cases
overdenture option as preventive prosthodontic treatment modality should be regularly imbibed in our dental practices because of its innumerable advantages Crum and Rooney graphically demonstrated in a 5 years study an average loss of 0.6 mm of vertical bone in the anterior part of the mandible of overdenture patients through cephalometric radiographs as opposed to 5.2 mm loss in complete denture patients. Millerin his study concluded that alveolar bone resorption depends upon three variables which are:1. The character of the bone.2. The health of the individual.3. The amount of trauma to which the structures are subjected.
Overdenture helps reduce shrinkage of surrounding bone and reduces pressure on the alveolar ridge. In case of overdenture prosthesis, proprioception is maintained, there is the presence of directional sensitivity, canine response and tactile sensitivity. The average threshold of sensitivity to a load was found to be 10 times as great in denture wearers as in dentulous patients .Rissin et al. in 1978 compared masticatory performance in patients with natural dentition, complete denture and over denture. They found that the over-denture patients had a chewing efficiency one-third higher than the complete denture patients. Overdenture with attachments can redirect occlusal forces away from weak supporting abutments and onto a soft tissue or redirect occlusal forces toward stronger abutments thereby resulting in superior retention. Attachments are often used in overdenture construction by either connecting the attachments to cast abutment copings or intra-radicularly. Overdenture attachments are classied either as studs, which connect the prosthesis to the individual tooth or as bars which connect the prosthesis to the splinted abutment teeth. They are further classified as rigid or resilient.
The success of the tooth-supported overdenture treatment depends upon the proper attachment selection for the particular case.
The attitude of the patient to the treatment should be assessed. Only those who understand the limitations and benefits of attachments should be treated with attachment retained overdentures. Hence, patient selection is critical to the success of the treatment. A tooth supported Overdenture is very much at the forefront as the treatment modality incorporating Preventive Prosthodontics concepts to the core.