Question for Gurus regarding full gold crown and Class II preps

[michiganboiler]

I have the foll questions about preparations of a class II MO Amalgam cavity on tooth 19 and Full Gold Crown preparation on tooth 3 and was wondering if anyone would be kind enough to answer them.

The questions are as follows:
(a) Regarding Class II:
(1) I am used to preparing this on a typodont. How different is it on a simulator in terms of chair position, access and visibility ?
(2) The axial wall depth needs to be 1.5mm and pulpal floor depth to be 1.5mm. If I maintain the axial wall depth at 1.5mm I am not getting enough gingival clearance from tooth 20. How can this be rectified ?

(b) Regarding Full Gold Crown:
(1) Same as question (1) in (a).

Once again I appreciate any help very much.

Thanks
michiganboiler

---

Members don't see this ad.

 

[waso]

Pulpal depth is 1.5mm, the gingival floor depth should have 0.5 mm clearance from the adjacent tooth, it should be 1.2 mm for premolars and 1.4 mm for molars in width, that's how I remeber it for class II. It's pretty much the same for Onlays, it all depends on how tight the contact is, the gingival floor is 3mm in depth for onlays. someone correct me if I'm wrong....

 

[dhaval]

hey there,
waso is absolutely right. for cl 2 u have to get a gingival clearance of .5 mm . the height of the walls dont matter.
for an onlay the height of the walls should be 3 mm and u should have enough clearance for taking a good impression i.e the impression material should not tear away on removing the tray.

 

[dentistindia96]

check ur pm