Following on from my recent post: Making Mistakes, I have decided to start up this thread which will constantly be updated to include some of my personal encounters on clinics as a dental student.

I will always try to be as honest as possible, offering my own hindsight thoughts, commentary and lessons. I guess I just want to create an outlet that I can use to put my experiences in writing, first and foremost for my own benefit, but also hopefully to share my journey with fellow dental students, dental professionals and prospective dentistry applicants.

The most recent ‘diary posts’ will be added at the top of this thread.

As always: any feedback, comments or ideas you might have – please share!


I couldn’t get my temporary crown off the prepped tooth!

Exciting times. I was doing my first anterior crown prep. It was a discoloured upper right lateral incisor that had been root treated (by me). I was looking forward to this appointment for a few weeks’ leading up to it – and had done my homework the night before so was mentally prepared for it. There was a pre-exisiting composite in the tooth’s crown- placed by a previous dentist. The appointment got off to a fine starty, my preparation went well. Fast forward one hour, I was doing the final refinements and was using the red band fine diamond to smooth the prep when all of a sudden the old composite just came out! Just like that, in the blink of an eye it flew out and was sucked up immediately by the high power suction tube. With my absolute inexperience when it comes to indirect restorations, I went into a mode of internal panic – trying my best not to outwardly express my panic to the patient. I stopped, asked my supervising clinical tutor to come over to check up on me as and they reassured me that it was relatively easily to address: I just needed to replace the composite and then refine the prep before continuing. I re-restored the tooth and made my preparation refinements – it didn’t take long at all. Then came the time to construct the temporary crown – I applied a light layer of petroleum jelly to the prepped tooth and adjacent teeth then injected the ProTemp bisacryl composite material into my putty matrix. My temporary crown didn’t come off! I tried to off as carefully as possible, whilst applying controlled force with my flat plastic – it wasn’t budging. After ~5 minutes of me struggling to get the temp crown off, I accepted it and just broke the temp crown off and made a new one. The rest of the appointment went fine – I took my impressions, refined the new temp crown and cemented it. Here’s the big lesson I learnt from this experience: the bisacryl composite temp crown material WILL bond to any freshly placed composite. That’s why I couldn’t get the first temp off – it had bonded to the surface layer of the resin material I had just placed in the tooth. Here’s hoping I don’t make the same mistake again – next time: more petroleum jelly and prep away oxygen-inhibited surface layer of any ‘freshly placed’ composite. And that is why we need to know our dental materials science!


Don’t place blind faith into old/existing restorations when working on a tooth. They might let you down

The lesson of the day was to replace old composites in a tooth before starting with a crown prep. The tooth being treated was a lower premolar, which was treatment planned for a full metal crown.

The tooth in question has been in the restorative cycle for many years. It had a large DO amalgam that had fractured then eventually came out during function after many years of service, which I then temporarily replaced with a GIC before then removing the temporary dressing and placing a composite core. The tooth also had a buccal composite, which had some staining around it at the restoration-tooth interface but no signs of secondary decay. The patient could not recall exactly how long ago the buccal composite was placed, but it looked like it had been there a long time. Anyway, the crown preparation was going fine until I was prepping the buccal surface – just minimally to acheive the ideal 0.5mm reduction with a chamfer margin. As I was doing so, the buccal composite just came out leaving a little hole in the side of the tooth. After a moment of panic from me, I resolved to quickly replacing it with a fresh well-bonded resin then refine the prep. The rest of the appointment went fine, although my temporary crown left a lot to be desired (I need to practice making temporary crowns more!).

One of the main learning points for me from this appointment was to examine any existing restorations before doing further work on a tooth, because you can never be sure of how well placed they were, how well looked after they have been by the patient etc. In hindsight, I should have anticipated this and replaced the old composite from the start – the staining around its margins was the big clue for me which I just ignored. Lesson learned.