Getting the Basics Right in Endodontics

Dr Stephen Harlamb

BDS, MDSc, MHLaw, MRACDS, FPFA, FICD, FIADT

As an Endodontist with over 20 years of experience as well as a degree in Health Law, I have noticed general dentists commonly ask questions with a recurring theme.

These newsletters will address many of your clinical endodontic and trauma questions, provide tips and other simple ‘dento-legal’ concerns that you may have. Being the inaugural edition, I have selected seven of the most common clinical questions I am asked.

1. What to irrigate with and for how long?Irrigating is an essential part of endodontic treatment and to this day I continue to use EDTA and 1% Sodium Hypochlorite (Na OCl) – I use a 5 ml syringe for EDTA and 10 ml for the Na OCl and in that way I can make a mental note to alternate their use – each time I put a file down I irrigate, alternating the two.
2. What to medicate canals with, when, and for how long?Calcium hydroxide (CH) remains the medicament of choice in infected cases – I spiral it in with a lentulo spiral, no nearer than 4 mm from the apex.
   I recommend leaving CH in the canal for no less than 14 days. Odontopaste® (which has replaced Ledermix®) is more often used in inflamed cases (pulpitis) and applied in the same way.
3. When to use antibiotics?
   Antibiotics are commonly misprescribed when it comes to endodontics – postoperative pain is often inflammatory in nature and as such NSAIDs such as Nurofen are most effective. Patients often will receive no relief with antibiotics, especially with an inter-appointment flare-up.
4. What instrument size to finish with and why?There are no hard and fast rules with the final sizing of canals. The final size is dictated by the initial file size which binds. See below:

   

   The initial size to bind here was a 70H. Hence the final prep size was a 100H.

5. What to obturate with and why?
   I still use the lateral condensation technique taught as an undergraduate all those years ago!! GP and AH+ with finger spreaders do the job just fine! I am not a fan of thermoplasticised GP with carriers – they make re-treatment quite challenging.
6. What to do if you don’t find the MB2 canal?
   Fourth canals (aka MB2, MBA), especially in upper 6s and 7s are more common than many think (over 90%)…so, therefore, assume one is there, and if you don’t find one, a specialist referral is recommended.
7. When to re-treat prior to crown placement?
   A contentious issue commonly debated as it can come down to a subjective rather than objective discussion. I tend to recommend re-treating (even if apically all appears fine) prior to crown placement especially if the endodontic history is vague or if there are radiographic deficiencies in the RCF. Nothing worse than cementing a crown and then followed by a flare-up!