Gus (Fig: 1) is an eminent and highly accomplished city architect with a great sense of style, creativity and aesthetics. He is also a dental phoebe.
We met a few years ago when he turned up on my doorstep with his partial acrylic upper denture in pieces and asked if it could be repaired? I suggested that he needed to see a dentist but he was adamant that he would not and asked if I would repair it as he had an important meeting to go to. I succumbed, repaired it and he was very grateful and happy.
Six months later he was back with charm and a promise that if I repaired it he would go and see a dentist.
The following year he was back with three remaining upper teeth blowing in the breeze and yet again his denture in pieces. This time I stood firm and insisted he let me arrange an appointment with one of my clients. With some persuasion, not least because he was unable to function dentally with resulting weight loss, he reluctantly acquiesced.
An alginate impression put pay to one of the remaining teeth and the last two soon followed.
Fig 1 – Gus with his poor fitting partial denture in situ
Stage 1 - Preparation and implant placement:
An alginate pick up impression was taken of the repaired and extended denture (Fig: 2a). The last three teeth were added. The denture was tidied up as best it could be so as to be used during the initial stages of treatment (Figs: 2b – c).
Seven implants (NobelBiocare – Branermark) were placed (Fig 3a) and a fixture head impression taken. Healing caps were then screw on and the denture relined with a soft conditioning liner and fitted (Fig 3b).
Fig: 2a Pick up impression of modified denture
Fig: 2b Labial view of modified immediate full denture
Fig: 2c Palatal view of modified immediate full denture
Fig: 3a Nobel Biocare, Branemark fixtures in situ
Fig: 3b Relined denture in situ
Stage 2 - Temporisation:
The fixture head impression was poured and a resin (Pattern resin LS – GC) framework fabricated on six of the fixtures using temporary cylinders (Figs: 4a – b).
Teeth (Heraeus Premium – Heraeus Kulzer) were set onto the framework for a tooth try – in (Fig: 5). The set up was tried in and the tooth arrangement was customised to Gus’s satisfaction (Fig: 6).
Back on the model, indices (Lab Putty – Coltene Whaledent) were fabricated of the tooth position from the try – in. The indices were used as a guide for the fabrication of the definitive teeth.
Fig: 4a Temporary cylinders on working cast
Fig: 4b GC resin framework attached to temporary cylinders
Fig: 5a Occlusal view of trial tooth set up
Fig: 5b Labial view of trial tooth set up
Fig: 6 Try in after modification
The try – in was then processed in autopolymerising resin (Palapress – Heraeus Kulzer) and used as a fixed temporary to replace the denture and to load the fixtures (Figs: 7a – c).
Fig: 7a Processed temporary
Fig: 7b Interim denture
Fig: 7c Screw retained acrylic fixed temporary
Stage 3 - Definitive restoration:
Fig: 8a Buccal view of GC resin framework built around definitive, cast onto, gold cylinders
Fig: 8b Occlusal view of framework
Definitive, cast to, gold copings with plastic chimneys were screwed in to the implant replicas on the master cast. A castable resin framework was then constructed to the copings (Pattern Resin LS – GC) (Figs: 8a – b).
Fig: 8c Full contour wax up over framework
Fig: 9a Wax up cut back to produce definitive framework pattern
Fig: 9b Framework sprued and ready to invest
Fig: 10a Cast framework on working cast
Fig: 10b Framework checked for passive fit
Fig: 11a Refined framework with access holes waxed out
Fig: 11b Framework sprayed with photosensitive powder
Fig: 11c Tooth preps being scanned
Using indices taken of the trial set up a full contour wax up was poured to the framework (Fig: 8c). A beam framework with individual tooth preparations was fabricated by cutting back the wax up (Fig: 9a). This was sprued (Fig: 9b), invested and cast in a beam gold alloy (BiO Degulor M – Degudent). The cast framework was checked back on the master cast (Fig: 10a) and then tried in the mouth to confirm fit (Fig: 10b).
The metalwork with its tooth preparations was refined (Fig: 11a), sprayed with a photosensitive powder (Fig: 11b) and then digitally scanned (Cerec In EOS – Sirona) (Fig: 11c).
Fig: 12a Labial view of virtual tooth preparation with margin outlined
Fig: 12b Occlusal view of virtual tooth preparation with margin outlined
Fig: 12c Virtual designed coping
Fig: 13a Close up of zirconia block in situ in milling machine
Fig: 13b Block ready to be milled
Fig: 13c Milling process in action
Fig: 13d Finished coping
Fig: 13e Close up of milled coping in inlab milling machine
Fig: 13f Milling coping in ‘green’ state
Fig: 14a Sintered copings in sintering tray
Fig: 14b ZYrcomat sintering furnace
Virtual images (Figs: 12a – c) captured by the scanner were used to design the copings to be milled in Zirconia. The Zirconia copings were milled (Cerec in LAB – Sirona} (Figs: 13a – e) and sintered overnight (ZYrcomat – Vita) (Figs: 14a – b).
Fig: 15a Labial view of zirconia copings in situ
Fig: 15b Occlusal view of zirconia copings in situ
Fig: 15c Occlusal view of zirconia crowns during occlusal adjustment
Fig: 15d Zirconia crowns at biscuit stage
Fig: 15e Zirconia crowns glazed
Fig: 16a Teeth cemented except over access holes
Fig: 16b & 16c Panavia cement used to cement crowns to framework
Fig: 17 Gingiva waxed up
Once trimmed and heat treated ceramic (VM9 – Vita) was applied to the individual copings (Figs: 15a – e).
Except where screw holes are located under the crowns the rest of the crowns were definitively cemented to the framework (Panavia – Kurarary Co. ) (Figs: 16a – c). The removable teeth were then seated and the gingiva waxed up (Fig: 17).
Fig: 18a Silicone mould for processing the gingiva
Fig: 18b Occlusal view of framework opaqued and ready for processing the gingiva
Fig: 18c Labial view of framework opaqued and ready for processing the gingiva
Fig: 19a Processing by injection moulding
Fig: 19b Occlusal view of processed restoration
Fig: 19c View of fitting surface
Fig: 20a Processed with access to screw holes
Fig: 20b, 20c & 20d Lateral and labial views of completed restoration
16a – c). The removable teeth were then seated and the gingiva waxed up (Fig: 17). After the access teeth were again removed, a putty mould was made of the gingiva, the wax boiled off, the metal opaqued with a pink, light cured opaque composite) (Figs: 18a – c), the mould reseated and the gingiva poured in an autopolymerising resin (Palapress – Heraeus Kulzer) (Figs: 19a – c). Trimmed and polished it was ready for fitting (Figs: 20a – d).
Stage 4 - Fitting the restoration:
Fig: 21a Torque- tightening the restoration
Fig: 21b Tightened and ready for remaining teeth to be cemented
Fig: 22 A natural look and a maintainable design
The temporary restoration was unscrewed and removed and the definitive screwed into place and torque tightened (Figs: 21a – b).
Lastly the remaining crowns were cemented over the screw access holes using a temporary cement to facilitate removal for access at future times (Fig: 22).
Fig: 23a Where’s that steak?!!!
Fig: 23b A fuller face smile of contentment
After many years of neglect with resulting periodic tooth loss until only three unsalvageable teeth remained in the maxillary jaw, our city architect was finally restored to full dental health and function with an aesthetic appearance which is much to his delight (Fig’s: 23a and 23b). Health is maintained with the assistance of superfloss and a waterpic. The screw retained structure is periodically removed for more extensive hygiene maintenance. Steaks are back on the menu and a fuller physique regained.