The next step in this case (see The Dentist, October 2010, page 104), with the lower was to produce a milled Coron chrome cobalt alloy structure using the Etkon scanner system (scanned by George Morgan of the Axom dental laboratory). See fig 8. Two lateral holes were prepared and tapped in the region of the first premolar through the milled framework and into the cast bar. The milled framework was prepared to accept ‘Ceramage’ teeth and gingiva as with the upper. Both structures were tried in the mouth to confirm fit, appearance and occlusal scheme prior to final finishing in the lab. A balanced occlusal scheme was produced to allow even spread of the occlusal forces, keeping the lower first molar teeth out of occlusion due to the length of the distal cantilevers (figs 9, 10, 11, 12 and 13). The angulation of the screw holes is critical in order that access is favourable for the placement of the tiny screws. The driver for these screws does not have a taper to grip the screw so a small piece of orthodontic wax was used to hold the two together. The driver was also modified to fit the end of a watch-makers screwdriver to ease handling when fitting. Due to the patient’s exciting gag reflex, a ‘safety net’ could not be used and so the above made the procedure much safer on fitting the bridges and saved my nurse’s nerves somewhat (and mine).
Figures 14–17 show the position and angulation of the screw holes and figures 18 and 19 the fitted bridges. Note the lack of screw holes through the labial or occlusal surfaces. A tiny amount of ‘Temp bond’ was placed over each abutment in the maxillary bridge to seal against bacteria. It was not felt necessary in the mandible due to the accuracy of fit of the milled framework. Fig 20 shows the patient smiling; note the low lip-line.The patient has been delighted with the result and the bridges have been in function for 12 months, during which time there has been loosening of one upper and one lower retaining screw. The opportunity was taken to remove the bridges to check the health of the periimplant mucosa, which was perfectly OK. A small amount of ‘Temp Bond’ was applied to each screw on re-fitting to prevent further loosening. Radiographs taken at fitting and after nine months show stable bone levels (figs 21 and 22). The patient receives hygienist care at three monthly intervals to assist and educate with the cleaning of these bridges. He now manages to maintain a very good level of hygiene.
I would like to express my thanks to Mark Proudlock of Solway Crown and Bridge Dental Laboratory for all his help and assistance in meeting the demands of cases such as this. And a final word to the patient, ‘Without doubt this treatment has brought a major improvement to my everyday living and I am very grateful for all your skills, care and attention that delivered this fantastic result for me.’
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