Restorative Dentistry
Mind the Gap – Again!
I do not know why it is that, when they see missing teeth, dentists have an urge to fill the space, usually with a plastic denture. Readers of my articles will remember from my article ‘Suffer little Children’ that I have serious doubts about the supply of dentures to children, and have proposed what I believe is not only a better clinical solution, but also a more cost efficient solution when all the costs of repairs, replacements and clinical time are taken into consideration.
We also know from the work of Kaiser in Holland, that replacing missing teeth with dentures is not necessary in the majority of cases providing that there are at least 10 functioning teeth in each arch.
There are alternatives. A very good friend of mine told me recently that he had had to have a maxillary first molar extracted and it would eventually be replaced by an implant after bone grafting. Meanwhile his dentist intended to make a plastic denture to fill the gap in the meantime.
My first thought was why? It is unlikely that in the 9 months or so that this treatment would take to achieve, that there will be serious adverse tooth movement and space closure. However, if this is a risk, then what alternatives are there.
Over 25 years ago, I had the privilege of being the first British dentist to be invited to Finland to look at the then new reinforced fibreglass material called ‘Stick’ (Sticktech, Turku, Finland). It is no exaggeration to say that this innovative material changed my way of thinking about many restorative problems and my clinical practice.
I would never provide a maxillary denture in this situation. They move, change speech, become loose at embarrassing times and are, in my opinion, a 19th century solution to a 21st century clinical problem.
My solution in this case, had I been given the opportunity to try my methods, would have been to make a modified Maryland Bridge. The same impressions that were taken to make a denture could be used. The laboratory can then construct wings of composite reinforced with ‘Sticknet’ mesh and bridge the gap with a pontic reinforced with ‘Stick’ rods. This can then be bonded in place in the usual way following air abrading of the palatal surface of the second standing molar and premolar, prior to acid etching and bonding in place with flowable composite and left in place until the final implant crown impression stage. Access to the surgical area could be achieved by drilling through the pontic for implant placement, with the hole refilled afterwards with flowable composite.
However, in this case I would not make a conventional pontic filling the whole of the space, the normal type to prescribe.
This would have disadvantages:
- If there is recession of the tissues under the pontic, then plaque control could become difficult
- It would be difficult to raise a flap under the pontic
- Due to the depth of the pontic, it could be quite difficult to drill through during implant placement.
In this situation I would advocate the use of that much older design of pontic, the sanitary pontic, which whilst closing the gap leaves a significant space underneath.
This would have the following advantages:
- Recession in the extraction site would not be a problem
- There would be access for flap raising
- There is less material to drill through and less risk of drilling out of line
- When the flap is raised for implant placement, it would be possible to see precisely the position of the drill tip in relation to the intended site to prepare the implant site
- The space under the pontic can be cleaned with large size bottle brushes, and especially the mesial surface of the second molar, and the distal surface of the second premolar, places that often retain plaque and where toothbrushes never reach. (see Toothbrushing and Spacemark in the periodontal section of this website).
Finally, if any colleague would like to try this solution and let me have photographs, I would be pleased to add them to this idea, with the usual acknowledgement of their contribution.