Looking back on my own thoughts Part 4

http://dental-tidbits.blogspot.com/2016/08/pre-endo-restorative.html
I remember this and the idiot who filled the whole pulp chamber with amalgam before the endo was complete. It took me about an hour and a half as a student to slowly dig all the amalgam out to reaccess the canals. Honestly, before an endo is committed to it is a good idea to remove all restorations to assess the restorability of the tooth. You'll look like a real fool if you get to the end of the treatment and the tooth can't be crowned because there's no ferrule to be gained. It is useful to check for cracks and to assess the restorative prognosis. Once the restorations are all removed you need to put one back. You can use a tofflemire or a metal band and bog the tooth up with GIC. In the past I have formed the proximal walls with composite resin and filled the central part of the tooth with GIC aiming eventually to replace the GIC in composite resin after the endo. Keep the end in mind, if you do this then you're relying on the bond between a future composite resin and your "old" interproximal composite resin. If you trust the chemistry then this may be okay. If it is a thin enough wall and will be removed during your crown prep then this is okay as well. However if you plan to use the composite resin as your final restoration and you don't trust the chemistry then it is just an unnecessary step as it will be removed before your final restoration. If you want to ensure your access cavity is not blocked with your pre endo restorative material I place cavit in the access cavity in the shape I want it to be after I restore. I then flow GIC in and around to firm the restoration. After setting it is very easy to remove the cavit and instantly have an ideal access cavity into the pulp chamber.

http://dental-tidbits.blogspot.com/2016/09/a-few-tips-from-c-marshall.html
Yeah I've restored fractured cusps like this quite a bit but haven't had the chance to follow them up. The issue I have with this now is that the retention of the entire palatal cusp is dependent on the MOD amalgam. The patients were amazed at how quick and easy the procedure was and how local anaesthetic wasn't needed. However you look a bit silly if the amalgam turns out not to have enough retention and your brand new filling pops off. The cost difference between a 532 (OP) and 534(MODP) isn't much and your surface area for bonding is a lot larger. Often as the amalgam preps are undercut, the actual exposed tooth structure after the palatal cusp fractures is quite minimal. Once a cusp is lost, the idea restoration is indirect and the patient should know this. If they can afford a crown or onlay they should get one otherwise you can compromise with a filling. However it is a bit too much of a compromise in my books to just patch up the tooth.

http://dental-tidbits.blogspot.com/2016/10/today-i-feel-like-ive-achieved.html
I remember this... 3 hours is a mammoth time for the two preps, impression and temporaries. I suppose I am used to working with an assistant which greatly increases your work speed. The preps weren't actually that bad but they were over prepped in every aspect (margin, walls and occlusal)

http://dental-tidbits.blogspot.com/2016/10/tips-from-dr-renner.html
Some really good tips in this post.
-I still use the technique of pre bending the file and introducing it apically. It is less likely to fracture  rotating before binding than rotating after binding but a less risky way to work apically is to introduce a small file passively and finding where it binds. Then introduce a rotary file till just before the binding point. This will widen the coronal aspect and the small file should be able to advance more apically. Continue this until you reach the apex.
-In regards to the margin prepped you could lower the margin more apically to try and separate the teeth or you can take a very thin bur and slice the contact open. If you prep a tooth for an indirect restoration and don't separate the teeth the impression material won't flow between the teeth and the technician won't be able to finish on a margin. Cleaning of cement from the crown margins will be impossible as you won't be able to pass floss through the area and it will be uncleansable. Often times the margin will end up deeply subgingival if you try and lower the margin till the teeth diverge. Anaesthetise the gingiva well and force a wooden wedge to separate the teeth. It will be easier to slice the contact open after this. If there is significant bleeding then apply your normal haemostasis protocols or temporise and impress next visit. A few years back I was asked to cement an anterior crown for one of my colleagues where they had not separated the teeth before impressing. It was impossible to pass floss through the contact and I'm pretty sure I stuck the teeth together. Now I would know better and would probably wedge the teeth apart for 10 minutes before I cemented. I would probably even wedge the mesial and distal contact apart and cement the crown with the wedges on.