Introduction
Sir, I read with interest R. Johns' response (BDJ2007; 203: 496–497) to my letter Downsides of implants (BDJ2007; 203: 228–229).
I would like to reiterate that I am not saying 'don't do implants' but that we should be aware that they cannot reproduce the original physiological situation and in particular in restoration of edentulous cases this is a point of future concern and ongoing study. There simply has not been enough direct research nor time elapsed to offer the 'no worries' approach yet.
The literature points out that jaw motor inputs from oral implants have only been examined to a limited extent.1 Edentulous patients in particular have been studied and an absence of a physiological 'silent period' in jaw closing muscles after tapping on the upper implants was noted. Direct studies are few and lacking to show that electrical and/or mechanical stimuli are transmitted via implants.
But there may be other concerns too. Neurosensory disturbances after immediate loading of implants in the anterior jaws have been noted and are being published.2 Experts are now recommending high resolution magnetic resonance imaging as a precautionary preoperative protocol in order to avoid disturbance of neurosensory complexes and thus avoid as much as possible risk of a pain-complex after surgery.3
In summary, there are significant differences physiologically between implants and natural teeth and data are still coming in to show this. It would thus seem premature to merely say that adaptation centrally can occur. After all, what nature has done to maintain over many tens of thousands of years (as can be evidenced from the beautiful micro-CT-based scans shown on the front cover of the BDJ recently) must have a purpose and to simply dismiss that would appear presumptuous at this point. Clinicians ought to warn their patients they are treading out on uncharted ground and that the 'no worries' approach is really not offering unbiased and fair informed consent as judged by today's somewhat litigious world.
