Dental Implants
Introduction:
Replacement of teeth requires the fitting of an artificial set of removable partial or complete dentures or crowns and bridges. Attempts have been made successfully by using dental implants as root analogs for tooth replacement. These anchored root implants in the jaw bone provide a stable foundation on which the replacement of teeth is firmly attached. Before illustrating the various techniques, it is necessary to analyze the indications for placing dental implants.
The predicament of edentulousness:
The first phase of edentulousness is a natural phenomenon in the newborn. If this persists beyond 9 months of age, the parents of the child become anxious to seek a dental opinion. Similarly, between the ages of 7 and 12, deciduous dentition is replaced by permanent dentition. If the second phase of edentulousness (partial) extends beyond 13 years of age, Orthodontist has an important role to restore the dentition. Due to various reasons, if the natural dentition is lost, the dental surgeon has to provide the dental prosthesis. In spite of satisfactory maintenance, loss of teeth occurs sooner or later. This is considered as an “aging process”. With the increase of life expectancy from 45 to 70 years of age, the need for dental prostheses also increases. Irrespective of chronological age, aging is viewed in different forms. Some view it as a biological process, while others look at it as a pathological process. While aging represents the passage of time, physiologically, it is considered as a progressive loss of functional capabilities. Therefore, the preservation of natural dentition is considered as one of the effective methods of slowing down the aging process in terms of the orofacial region. That is why, in the event of losing natural dentition, the dental profession has been in search of a satisfactory method of reconstructing the dentofacial region. It is in this direction, Dental implants are considered as one of the viable alternative treatment options for managing edentulousness.
Dental implants – How?
Unfortunately, most of the conventional prosthetic options remain unpredictable. Absence of any reliable “prediction tests” for the maladaptation of the prosthesis associated with increased longivity of life have made the management of edentulous aging patients very challenging. To avoid insecure feeling, patients prefer fixed bridges even though, grinding of the natural teeth is necessary.
In the past two decades, there has been a revolution in atleast one aspect of dental practice: namely – development of a relaible implant system to provide anchorage to the prosthesis. The main aim is to provide long term stability abd high level of acceptance by the patient. Formerly, the dental surgeon attempted to simulate the tooth attachment by providing a soft tissue interface, very similar to periodontal ligament. During 1970’s, Branemark and Schroeder demonstrated that osseointegration is essential for the long term success of the implant. Prerequisites for achieving the osseointegration are as follows:
- Implant material must be biocompatible.
- Establishing the primary stability of the implant.
- Atraumatic surgical procedure.
- Optimal loading of the implants.
Life-long maintenance of the peri-implant tissues.
Dental Implants – When?
Restoration of the masticatory function is the most important indication for the insertion of oral implants. Wherever implant is the only alternative treatment option, then it is termed an Absolute indication. In all the other clinical situations, it should be considered as one of the viable alternatives, then it is called Relative indication. Complete edentulous jaws and posterior unilateral or bilateral edentulous spaces are examples of absolute indications. All the other forms of edentulousness like single or multiple tooth loss bounded by teeth on either side are examples of relative indications.
A predictable prognosis is the main criteria for advocating implant-supported prostheses in all the above-mentioned clinical situations.
Restorative Indications:
For oral rehabilitation some other factors play an important role apart from the restoration of the chewing function. Esthetics seems to be the most important motivation – factor for many patients who need prosthetic replacement of anterior teeth. To get an esthetically acceptable rehabilitation, sometimes, we have to reconstruct the recipient bed, including the augment the bone and soft tissues. Many pre-prosthetic reconstructive procedures require bone grafting. It is an established fact that only loaded bone does not resorb. Therefore, implants insertion on the grafted bone can help to avoid bone resorption. The biological basis of the bone healing and clinical experience form the basis for this indication.
Palliative indication:
In cases of functional and restorative indications, we speak about long-term prognosis. On the contrary, the aim of palliative indication is to improve the quality of life of the patient, so long as the patient lives in comfort. For example, patients with oral malignancy undergo jaw resection. If these patients are reconstructed to avoid an oro-facial deficit, provision of dentition is a difficult proposition. Implants in the reconstructed jaws help the patient to live in comfort with a prosthesis. Likewise, implants can be placed in the irradiated bone, even though the bone is of inferior quality. Similarly, implant-borne prosthesis in patients with strokes, and hemiplegia form excellent palliative indications.
It is time for us to consider the transition from the conventional implant-supported prosthesis to the functional, restorative and palliative indications as a realistic proposition in implantology practice.
Dr.B.Srinivasan
43/3, Beach Road,
Kalakshetra Colony,
Besant Nagar,
Chennai, Tamil nadu, India – 600090
[email protected]
