Presentation from Prof Paul A. Tipton, for Smile GB, on Gold preps

1. Dr. Paul A. Tipton
In a study by Dr RV Tucker involving
1314 gold restorations over a period
of 52 years the success rate over a
40 year period was 94.1%
Dr. Paul A. Tipton
tooth preparation

2. Dr. Paul A. Tipton
gold ¾ crowns (upper)
Dr. Paul A. Tipton
tooth preparation

3. Dr. Paul A. Tipton

4. Dr. Paul A. Tipton
reduce the occlusal surface by approx. 0.5 - 1mm depending on the occlusion and position in the arch , use depth
cuts of 0.3 – 0.75mm, slightly less as you approach the buccal cusp tip – depending on whether the tooth is in
guidance or not. Keep the correct cuspal inclines

5. Dr. Paul A. Tipton
prepare functional cusp bevel by extra ½mm
angle the bur so that it
prepares the functional cusp
bevel at approximately 45° to
the occlusal plane

6. Dr. Paul A. Tipton
prepare palatally with ½ mm chamfer bur

7. Dr. Paul A. Tipton make sure your margin is just supragingival

8. Dr. Paul A. Tipton st ann’s
break through distal contact first
using long thin diamond

9. Dr. Paul A. Tipton
place the chamfer finish line supragingivally. finish with fine diamond or carbide bur

10. Dr. Paul A. Tipton
place distal groove supragingivally using
tapered carbide bur with a slight angulation -
the same as the palatal wall
aim towards opposite corner of the tooth. the
bur should engage half its width. use speed
increasing handpiece

11. Dr. Paul A. Tipton
break through mesially with long thin diamond and increase width until thin chamfer
bur can produce supra- gingival margin without damaging the adjacent tooth

12. Dr. Paul A. Tipton
finish the margin with fine diamond or carbide chamfer bur. use speed increasing handpiece

13. Dr. Paul A. Tipton
place the mesial groove the same way using carbide tapered bur with speed increasing handpiece.
angle the bur so that it is upright and you have a “line of drawer” when looking from the buccal.
then flare the groove to the cavo surface margin using a flame shaped fine diamond or carbide bur
in a speed increasing handpiece. the angle should be the same as the palatal wall

14. Dr. Paul A. Tipton
the groove should be
angled towards the
opposite corner of the
tooth and half the depth
used. the mesial groove
should not be seen from
the front of the mouth
and should be hidden
by the distal aspect of
the canine tooth

15. Dr. Paul A. Tipton
cut an occlusal off set between grooves using tungsten carbide flat ended bur
by cutting with one corner to produce a 90° v-shaped but shallow ditch.

16. Dr. Paul A. Tipton
the offset is there to strengthen the thin occlusal cavo-surface margin and give
structural rigidity. use speed increasing handpiece

17. Dr. Paul A. Tipton
the offset is cut so that it follows the buccal cusp outline in a shallow v

18. Dr. Paul A. Tipton
the final preparation involves a ½ mm bevel on the buccal cusp tip using a fine diamond or carbide
bur in a speed increasing handpiece. make sure you have a “line of draw” from the buccal before
taking your impressions. this is done by ‘wiping’ the bur over the buccal cup

19. Dr. Paul A. Tipton

20. Dr. Paul A. Tipton
reduce the occlusal surface by approximately 0.5 - 1mm – use depth cuts.
slightly less as you approach the buccal cusp tip – maintaining the correct
cuspal inclines (unless in guidance)

21. Dr. Paul A. Tipton
reduce the functional cusp bevel by extra ½ mm at 45° to the occlusal plane

22. Dr. Paul A. Tipton
use carbide bur with flat cutting edge to place a 1/2mm shoulder

23. Dr. Paul A. Tipton
the shoulder is placed 1mm apical to the opposing tooth contact

24. Dr. Paul A. Tipton
cut out a MOD cavity. remove the MOD amalgam and prepare a MOD inlay
preparation with a 12° angle of convergence

25. Dr. Paul A. Tipton
prepare the boxes
with sharp line
angles and similar
angle of
convergence
the boxes should be
apical to the MOD
cavity (usually!). use
speed increasing
handpiece and
carbide bur to finish
the preparation

26. Dr. Paul A. Tipton
place a flare
(fine bevel)
between the
boxes and the
cavo-surface
walls of the
preparation
using speed
increasing
handpiece

27. Dr. Paul A. Tipton
place a flare (fine bevel) or bevel to the bone
of the box with fine diamond or carbide bur
in a speed increasing handpiece
make sure the contact areas are broken

28. Dr. Paul A. Tipton
complete the preparation by continuing the flare (fine bevel) onto the buccal cusp tip and bevel
the palatal shoulder with fine diamond or carbide bur using speed increasing handpiece. make
sure you have a “line of draw” from the buccal.

29. Dr. Paul A. Tipton
make sure that the axial walls are 6° and there is a “line of draw”

30. Dr. Paul A. Tipton

31. Dr. Paul A. Tipton
the boxes should be square internally, with a flare to the contact point with the adjacent
teeth. the boxes should break the contact point with the adjacent teeth

32. Dr. Paul A. Tipton

33. Dr. Paul A. Tipton
reduce the occlusal surface by 1mm using depth cuts and
maintaining the correct cuspal angles and inclines

34. Dr. Paul A. Tipton
reduce the buccal cusp (functional cusp bevel) by extra ½ mm

35. Dr. Paul A. Tipton
place the functional cusp bevel at 45° to the occlusal plane

36. Dr. Paul A. Tipton
cut a ½ mm shoulder 1mm apical to the opposing tooth contact using flat
ended carbide bur in the speed increasing hand piece

37. Dr. Paul A. Tipton
start the lingual preparation using a chamfer bur, placing a ½ mm margin supragingivally

38. Dr. Paul A. Tipton
break through the contacts mesially and distally using a thin diamond bur

39. Dr. Paul A. Tipton
introduce wider burs
until the chamfer
prep bur can place a
½ mm chamfer
confluent with the
lingual preparation

40. Dr. Paul A. Tipton
prepare tapered grooves with supragingival margins mesio-buccally and disto-bucally
using speed increasing handpiece and carbide bur

41. Dr. Paul A. Tipton
place a flare
between the groove
and the cavo-
surface margin with
fine diamond or
carbide bur using
speed increasing
handpiece . ensure
you have a “line of
draw” from the
buccal.

42. Dr. Paul A. Tipton
to finish the preparation place a bevel on the buccal shoulder margin with fine
diamond or carbide bur using speed increasing handpiece

43. Dr. Paul A. Tipton st ann’s dental clinic

44. Dr. Paul A. Tipton

45. Dr. Paul A. Tipton
cut 0.75mm depth cuts reduce occlusal surface by 1mm

46. Dr. Paul A. Tipton
maintain cuspal shape during occlusal reduction

47. Dr. Paul A. Tipton
cut 0.5mm gingival chamfer

48. Dr. Paul A. Tipton