Dental implants can be extremely useful for denture wearers by incorporating them within the prosthesis to help the retention and stability of the denture. In the lower jaw a minimum of 2 implants can be life changing for patients with a full lower denture. Normally a lower denture does not have much suction especially if there is little remaining ridge and/or if the ridge is very flat. The denture stays in by gravity i.e just by resting on the ridge and neuromuscular control of the denture by the patient. They simply learn to control the denture with the cheek and tongue.
The good news is that it doesn't have to be this way, a minimum of 2 implants can be placed in the lower jaw with an attachment called locators to which the denture can 'click' on to providing excellent stability and retention. Many patients find this life changing both from a functional and social aspect..no one wants their denture to fly out when they are talking!
A thorough examination and assessment is required before any implants can be placed including a CT scan (3D Xray) to assess bone volume and quality. When there is little bone volume remaining, which is often the case if the dentures have been worn a long time, narrow or small diameter implants can be placed. These are designed specifically for these types of situations. The Straumann narrow implant is only 2.8mm in diameter and is a great option for narrow ridges.
If the anatomy is favourable a greater number of implants can also be placed. A removable denture on 4 locators is extremely retentive and prevents tipping movements too. Locator inserts which are located on the fitting surface of the denture are available in different colours depending on the strength of retention required. With use these plastic inserts can wear away affecting the retention of the denture however they can be replaced and do need replacing at least once a year. This is a relatively straightforward process and your dentist will have a special tool to remove the inserts and replace them with new ones. The on going cost of regular replacement of these inserts needs to be factored in before you proceed with dental implants, albeit a relatively inexpensive process.
Bite force can affect the wear of the locator inserts - a patient with strong jaw muscles and a strong bite will need to have the inserts replaced more frequently as they will wear quicker.
When the teeth are lost there are certain changes which occur in the jawbone. There is a gradual process of bone loss especially when dentures are worn, the rubbing of the denture contributing to the loss. The pattern of bone loss in both directions, horizontal and vertical which means the ridge becomes narrower and shorter in height. Unfortunately this process does not stop however placement of implants can help to retain the bone height as it stimulates the bone during function.
In the upper jaw a full denture has better suction especially if the palate is deep and/or if the remaining bone is of good quality and quantity however relies on extensive mucosal coverage i.e needs to cover the roof of the mouth. This can affect taste and comfort as the denture can be very large and no one wants a large piece of plastic in their mouth!
Dental Implants can also be used to help retain the denture in the upper arch too. Generally a total of 4 implant locators are placed in the upper arch to help distribute the forces. The overdenture can then be made a 'horseshoe' shape as the palatal coverage is not required for the extra retention. This means less plastic in the mouth and no need for messy denture adhesive. Partial dentures can also be used with dental implants to help retain them in exactly the same way.
Dental Implants are an extremely versatile option for the denture wearer and can be life changing if utilised correctly in the right case.