Implant Bridge

by Dr. O. Karnakova

An implant bridge may be a good option to replace multiple missing teeth, and are far superior to removable partials or multiple tooth supported bridges. An implant bridge is very similar to a normal bridge, in which there are abutments and a pontic. They also offer many advantages such as stopping bone resorption, preserving adjacent teeth, and act and feel like natural teeth. Implant bridges also require hygiene similar to that of a normal bridge, and have a much greater long term prognosis when compared to multiple tooth bridges.

In the past, implants were bridged to natural teeth and are now not recommended.  Research has shown bridging an implant to a natural tooth can cause many complications and decrease its prognosis. Natural teeth are connected to the bone via ligaments while implants are integrated directly into the bone.  The ligaments on natural act as a cushion and provide slight mobility. The difference in resilience between the natural tooth and implant can cause fractures of the tooth, failure of the bridge, and mobility of the implant. It is highly recommended to instead place multiple implants with single crowns.

Generally, there are two types of abutments for implants. Stock (pre-fabricated) abutments are manufactured by the company, but may not fit properly to the contour of the gums. Custom abutments are made by the dental laboratory. An impression is taken of the implant and surrounding gums. A custom abutment will offer a perfect fit of the crown and will better resemble a natural tooth.

The role of orthodontics in Implant dentistry.

by Dr. Nadia Abazarnia, DDS

Orthodontics can be used to develop the peri-implant site prior to implant placement. Orthodontic treatment for children and adults can involve management of teeth missing due to agenesis, trauma, or extraction following dental disease or malformation.

An interdisciplinary approach between the dentist and orthodontist, and often the implant surgeon and prosthodontist, is usually  required to formulate the most appropriate treatment plan for the patient. A decision usually needs to be made as to whether the space or spaces should be closed orthodontically, or maintained for eventual prosthetic replacement.

Over the last decade the reliability, predictability and long term success rate of implants has made them the prosthetic replacement  of choice, especially when the teeth adjacent to the space are well formed and unrestored. When it is planned to incorporate  implants into the orthodontic and restorative treatment plan, growth considerations, implant space requirements and implant site development are three of a number of treatment planning factors that need to be considered.

Growth Considerations: It is not usually appropriate to place an implant until completion of dento-alveolar development and skeletal growth. Throughout active growth the implant responds like an ankylosed tooth while the adjacent teeth continue to erupt, creating a discrepancy between the gingival margin of the implant and the natural teeth. Particularly in a patient with a high lip line, this will produce a poor aesthetic result unless implant treatment is delayed until growth has been completed. Chronological age alone is not accurate in determining whether growth has been completed for an individual. We expect that most girls will have completed the majority of their active facial growth by 16 years of age and boys by 19 years of age. However, boys in particular can show significant late facial growth. Radiographic examination can help to determine whether active facial growth has been completed.

Although active facial growth may be considered to have been completed in the late teens or early twenties, continued facial maturation and changes, including in the vertical dimension, continue throughout the individual’s life. The space required for implant and crown replacement will be determined by a number of factors including the size and shape of the contralateral tooth, the size of adjacent and opposing teeth, aesthetics, the occlusion and by the size of the implant to be used.

In some situations the orthodontist may be forced to create more or less than the ideal space required for the implant due not only to the size of the teeth but also in order to establish normal overjet and overbite. Options to be considered, in consultation with the restorative dentist or prosthodontist, are whether adjacent teeth need to be increased in width using adhesive restorations, veneers or crowns, or whether the width of the teeth needs to be reduced by interproximal stripping and crown recontouring.

The incorporation of orthodontic therapy into comprehensive treatment planning is a valuable adjunct which can enhance aesthetic and functional outcomes in restorative dentistry.

Reference ; Australian society of orthodontists