Removable full denture
Implant Supported Overdenture
The name of the lower jaw bone is called MANDIBLE. It is U shaped single bone attached by two joints called TM Joints to the base of the skull. There are very powerful ligaments and muscles which moves this bone for effective chewing. You will be surprised to know the force exerted between the back teeth and it can be up to 150 kg per sq inch. This jaw bone can move in many directions for pulverizing the food that we take. There two nerves which traverse this bone from either side entering from the back inside and exiting the bone outside between the two premolars. This jaw bone holds 18 teeth in total.
The part of the jaw bone holding the teeth starts shrinking and you will loose the shape of the face. Impairment of chewing and speaking causes social and health problems.The only treatment that can prevent shrinking of bone is to place implants.The jaw bone recognizes the implant as the lost root of the teeth. The function imparted by the implants increases the density of the bone and the shape is maintained. So dental implant is done not only for cosmetic reasons but also for functional reasons.
The jaw bone shrinks to such an extent even the placement of implants will be difficult. Additional surgical procedures will be needed to place the implants.Some of the surgical procedures to augment jaw bone that can be mentioned are as below.
Long periods of tooth less condition will lead to shrinking of jaw bone both in vertical and horizontal dimension. At scientific dental clinic Dr Thomas routinely does ridge split technique using piezo electric bone surgery unit. This specialized machine work with piezoelectric mechanics. The knife edged thin bone is split and widened to accommodate the correct size of implants and interposition bone graft is used at the time of placing implants to fill the dead spaces.This is a highly successful surgical treatment.Dr singh usually does this under local anesthesia .Careful handling of the bone is very important to maintain the blood supply of the bone and in turn the integration of implant.
This also is done as two stage procedure where the ridge split is done with bone grafting as the first procedure. Once the bone is augmented to the desired width after a healing period of six months implants are placed. But in 99% of the cases Dr Thomas places implants at the time of ridge split and a second surgery is avoided. Those who are not trained to do this procedure usually discourage patients advising them that they have no bone and hence they are denied the opportunity of replacing lost back teeth with dental implant treatment thus compromising the quality of life
Long periods of tooth less condition will lead to shrinking of jaw bone both in vertical and horizontal dimension. To increase the width and height of the jaw bone to accommodate a good sized implant a piece of bone (block of bone) is harvested from a site near to the implant placement site. The usual site for harvesting the block graft is from the chin, ramus of the mandible, ankle of the mandible etc. Dr Thomas does this procedure also under local anesthesia. The graft harvested is fixed on to the thin jaw bone where an implant cannot be placed otherwise. Fixation of the block graft is done by titanium osteosynthesis. Interposition graft is also used along with this. Since the donor and recipient sites are in same region patient discomfort is minimal.
In severely shrunken lower jaw the inferior dental nerve will traverse through the center of the bone. Any surgical intervention will violate the neuro – vascular bundle leading to neurological deficit. Using specialized equipments and instruments this nerve can be tunneled out from the bone and implants can be placed safely in the bone.
To replace all the teeth in the lower jaw 6 implants are needed. The placement of implants can be done in one surgery or a maximum in two days time. The time needed will be one hour each.In three days time a temporary denture will be fabricated and given.
Two to four implants can be used to stabiles the denture. With this treatment you still have to remove the denture. But this is cost effective treatment for stabilizing a very loose denture.
Single piece implants with ball heads can be inserted to the jawbone and dentures can be immediately loaded. This is very quick and less expensive treatment to stabilize the denture. Since the implants are loaded immediately the success rate of such implants are less than a two stage treatment. In two stage treatment you leave the implants submerged in the bone for Osseo - integration to happen. With this treatment the success rate is as good as any two stage process. The advantage of this treatment is that at a later stage more implants are placed then this can be converted to complete non removable implant supported prosthesis.
In the lower jaw dental implant treatment is very successful. 98% success is easily achieved. The healing period between the first and second stage is only three months and implants can be loaded much quickly compared to the upper jaw.
The artificial teeth can be metal fused porcelain crowns which can be cemented on to the abutments or screw retained. In case of severely shrunken jaw and when the patient has facial changes hybrid dentures are the choice. This has the features of dentures and crowns.In some cases dentures can be stabilized by implants as over dentures or bar retained dentures.
In normal mandible implants can be loaded in three months time. When surgical techniques are used to augment the jaw bone by bone grafts etc more healing period is required and up to six months are needed.
When complete replacement of lower teeth is done dental implants there is difficulty in stabilizing temporary denture. There are no existing teeth to which the denture can take support by way of clips or other accessories. The temporary denture can also exert pressure to the implants impairing the union of implants to the bone.
To help the situation transitional implants are used to support the temporary denture. These are very slender implants which are single piece unlike the conventional implants which are totally buried in the bone under the gum. The TRI will protrude thru the gum and has a ball head. The fitting surface of the denture will have nylon ring to snap fit into the transitional implant ball head. This mechanics give stability for temporary denture.
The life of transitional implants is less than conventional implants are they are immediately loaded. By any chance if the TRI also get integrated then it will also be incorporated into the permanent teeth.Two TRI are needed in each jaw making four TRI for the full mouth.