An implant is a prosthetic device or a screw of alloplastic material (commonly titanium alloy) that is implanted into the oral tissues beneath the mucosal layer within the bone to provide retention and support for a fixed or removable prosthesis.

 

  • Replace one or more teeth without affecting bordering teeth.
  • Support a bridge and eliminate the need for a removable partial denture.
  • Provide better retention for a denture, making it more secure and comfortable.

The ideal candidate for a dental implant is a person of any age in good general and oral health and free from gum disease. Adequate bone in your jaw is required to support the implant.  Clinical assessment is required to assess if this treatment is right for you.

 

Bone augmentation maybe required if sufficient bone is not present.  This can be

1. Xenograft bone: This is harvested from animals, most commonly treated bovine bone (cow).   This is usually used if the graft required is small.  

2. Autogenous bone: This is your own bone taken from a different site to the site of the implant).  The autogenous bone can be taken from another part of the mouth or the iliac crest (the hip). 

3. Allograft bone: This is similar to your own bone but it is taken from a human donor that is rigorously checked and  sterilised before use.

4. Alloplastic bone: This is a synthetic man made version of bone.  

 

A barrier membrane is usually placed over the graft to prevent its resorption whilst the healing process is taking place.  This eventually gets resorbed and replaced with your own tissue.  All bone grafts get assimilated within and into your natural jaw bone overtime.

 

Depending on the amount of augmentation needed, you will be advised of the type of graft that is most suitable for you.

1. Smoking

Bain and Moy1 have shown a higher failure rate of implants in individuals that smoke.  This particular study reviewed the outcomes of 2,194 implants placed in 540 patients over a six year period.   The overall failure rate of 5.92% was consistent with other studies; however, when patients were subdivided into smokers and non-smokers, it was found that a significantly greater percentage of failures occurred in smokers (11.28%) than in non-smokers (4.76%).  Many recent studies confirmed the same findings.  Sanchez-Perez et al2 found that the dose of tobacco affects the risk of implant failure with the risk increasing from 10% to 30% from light smokers (less that 10 cigarettes per day) to heavy smokers (greater than 20 cigarettes per day).  Therefore, it is recommended that you stop smoking prior to implant placement to reduce the risk of implant failure.

1) Bain and Moy: The association between the failure of dental implants and cigarette smoking, International Journal of Oral and Maxillofacial Implants 1993; 8:609-615

2) Sanchez-Perez A, Moya-Villaescusa MJ, Caffesse RG.  Tobacco as a risk factor for survival of dental implants.  J Periodontol 2007; 78:351-359

 

2. Bisphosphonates

Bisphophonates are a class of medications given to those that suffer from osteoporosis as well as other disorders.  There is evidence that prolonged use of bisphosphonates, particularly if given intravenouly, is a contraindication to all elective oral surgical procedures including implant placement.  It may lead to a condition called osteonecrosis which is exposed painful necrotic bone in the jaw as it suppresses bone turn over.  Ideally, surgical treatment should be performed well before commencing the therapy.  

Scully C. et al:  Dental Endosseous Implants in patients on bisphosphonate therapy. Implant Dentistry 2006; 15 (3):212-218

 

3. Haemophilia and other blood disorders

The operation is essentially simple and usually requires a short duration.  Both jaws can be treated simultaneously. 

 

An incision will be made via the gum in order to expose the jawbone.  The implant will be inserted, and then the incision will be closed with resorbable/absorbable stitches.  The gum area will heal within one to two weeks.  It takes approximately three months for osseointegration (close relationship of the bone to the implant) of the implant. 

 

Implants can be placed as a one or two stage surgery.  If primary stability is achieved (i.e. the implant is secure in place at the time of placement), one stage surgery can be done, i.e. a healing cap can be placed at the same time of implant placement.  If the implant is placed in soft bone or at the same time as a grafting procedure, then two stage surgery is required (i.e. the implant is buried in the bone and allowed to heal for two to three months, depending on the implant system used, then at the end of the healing period, the second stage surgery is carried out.  This involves uncovering the implant with a small gum incision then attaching the healing cap.

 

Impressions/moulds of the implant/s will then be taken for the fabrication of the restoration/s planned.