Computer Aided Implant Placement
Inserting a dental implant is a tricky affair which requires a fair degree of accuracy. It is a highly skilled procedure which requires the dentist to know beforehand the exact position for the implant. This is done using diagnostic tools such as x-rays or CAT scans but it is very difficult to determine the precise location for the implant or the amount of bone density in a patient’s jaw.
However, advances in dental technology such as computer aided implant placement have made this much easier to do. Technologies such as Cone Beam Scanning, 3D imaging software and Surgical Guides can achieve extremely high levels of precision that were unheard of a few years ago.
This form of ‘virtual dentistry’ enables dentists to diagnose and plan treatment schedules that start with the initial consultation stage right through to the actual procedure.
If you are interested in a high-tech approach to implant dentistry then read on…
The process starts with an initial consultation with the dentist. This might be your own dentist or a referral to a periodontist.
During this consultation the dentist will discuss the treatment with you as well as asking you about your medical history. He or she will also examine your teeth before sending you for an x-ray or CAT scan. A CAT scan gives a more accurate representation of your teeth than an x-ray as it builds up a 3D image of your teeth and jaw.
However, there is a more advanced type of scanner now available called Cone Beam CT.
Cone Beam Scanning (Cone Beam CT)
Cone Beam Computerised Tomography differs from conventional scanning in that it emits a ‘cone beam’ of radiation that captures an entire image, as it revolves around the patient in a single rotation.
High resolution 3D images of the teeth and jaw are produced via a series of algorithms. These representations are very accurate and help with implant placement.
Another feature of this scanner is that the patient sits up for the procedure rather than lying down as with the conventional scanner. Lying down tends to result in a collapse of the soft tissues of the mouth which is not the case with the Cone Beam scanner hence the more precise representations.
These images are then used with 3D imaging software such as SimPlant (ref: Materialise Dental) which helps the dentist to decide upon the placement of the implants.
3D Imaging Software
Imaging software such as SimPlant (www.materialise.com) is a very useful tool when planning a course of dental treatment.
It shows a highly realistic 3D representation of the patient’s jaw which can be explored from all angles. The dentist can also place ‘virtual’ implants which enable him/her to check the positioning and make adjustments if necessary.
Plus it can be used to show the patient a step by step process of the implant procedure. If you are unsure as to how the procedure works then this will demonstrate it to you. And, it can give some extra reassurance if needed.
The implant placement model will consist of precise measurements and positioning which is based upon an individual patient’s anatomical structure.
This model is saved and then exported as an email attachment to a dental laboratory. The laboratory will then use this to produce a surgical guide for the actual implant procedure.
A surgical or ‘drill guide’ is a solid template which fits over the patient’s teeth during the procedure. It contains a number of ‘guiding cylinders’ which correspond with the intended placement of the implants.
For example, if you are having 5 implants then there will be 5 guiding cylinders.
The dentist will drill down each one of these cylinders before placing the implant.
The exact position of these cylinders will have been determined by the measurements obtained from the 3D model.
A leading dentistry firm - Materialise Dental (www.materialise.com) have produced their own drill guide – called SurgiGuide which they see as the point at which the dentist moves from the virtual to real world implantation.
There are 3 types of SurgiGuide:
- Tooth supported
- Bone supported
- Mucosa supported
Another leading dental firm – Nobel BioCare (www.nobelbiocare.com) have produced a very similar system called NobelGuide which is a CAD/CAM template that fits over the patient’s teeth during the procedure.
They have used this system as part of their immediate loading product – which is also known as ‘teeth in an hour’.
SICAT (www.sicat.com) are specialists in 3D imaging software for the dental implant community and have produced their own range of surgical guides for implant placement. These guides work in much the same way as they exist as an aid during the implant procedure.
How does it work?
If you are having the implant and crown in the one session – a process known as ‘immediate loading’ then the procedure is as follows:
- The drill guide is placed inside your mouth and fits neatly over your other teeth.
- The dentist uses this to aid him/her with drilling into your jawbone before placing the implant.
- The implant is inserted.
- The dentist checks the placement of the implant and then removes it. This has to be done before removing the drill guide.
- Once the guide has been removed he/she will replace the implant and then attach the abutment. This acts as a connection between the implant and the crown.
- The dentist will then attach the crown to the abutment. This crown looks and acts in much the same way as a natural tooth.
Computer aided imaging can also help the dentist to decide if a bone graft is required which is a common issue with dental implants.
Other potential uses include the fields of orthodontics and oral and maxillofacial surgery, for example, the diagnosis and treatment of temporomandibular joint disorder (TMJD).