What is the deal with buffered dental anesthetic?
The theory is that buffering anesthetic makes the injection less painful as it changes the pH of the solution from acidic to a close to neutral pH. It is also theorized that the anesthetic can work faster and be more profound as anesthetic doesn’t work until neutral and in a neutral solution more anesthetic molecules per volume are active. We use sodium bicarbonate to neutralize our anesthetics. The FDA has approved two products in dentistry to be used to help buffer lidocaine, although anyone can go “off=label” and buffer by themselves or buffer articaine. Anutra and onpharma both are products used in dentistry to buffer anesthetic.
This is not a new technique, in fact it was stolen from medicine. The medical systemic reviews do tout it’s benefits. The dental research is a bit more cloudy.
My personal take from the research and personal experience is that there is a 10-20% group of times/patients where the anesthetic is less painful and works faster to a measurable extent. Teeth that are severely inflamed seem to be better candidates for using buffered anesthetic. One advantage for dentistry with the Anutra system is it allows us to inject up to 6 ml of anesthetic with one injection (most studies on lidocaine show no statistical difference based on amount given, yet they all show more being slightly better Sept 15 Abazarpoor). Previously dentists could inject 1.8ml and then would withdraw needle, reload, and inject again. So it is less traumatic in that regards. I feel it is most beneficial for blocks, extreme pain, and infected areas.
Lit review with 5 of the studies found below show it is effect for teeth with pulpally involved teeth JADA 2019 Kattan
- Max anterior – Depth, time of onset, and level pain all better with buffered for PA surgery Al-Sutan Al-Rafidain Dent J 2006
- Extraction max molars with inflammation – Buffered better for everything Gupta OMS 2013
- IAN block – Statistically same? but buffered beat by 63% vs. 48% Saatchi Jan 15
- IAN block – Same pain level injection, anesthetic success level same statistically (although it was 40% buffered and 32% not) – Schellenberg June 15
- Much better for first mandibular molars with irreversible pulpitis when used as buccal infiltration before traditional block. Saatchi JOE 2016
Multiple Medical systemic reviews have shown less pain upon injection, especially in sensitive areas. Davies Buffering the pain of local anaesthetics: A systematic review. Hanna 2009 Cepeda 2010
Max infiltraion – Less pain injection, same depth, Faster onset. Depth was better in teeth with peri-apical lesions. Al-Sutan Al-Rafidain Dent J 2004
IAN block – Faster onset and less pain Malamed 2013
Block – Onset quicker and less pain Kashyap JOMfS 2011
IAN block – Anesthetic success same, same onset, same pain level A prospective, randomized, double-blind study of the anesthetic efficacy of sodium bicarbonate buffered 2% lidocaine with 1:100,000 epinephrine in inferior alveolar nerve blocks Whitcomb 2010
Infiltration I&D – Same everything Balasco JOE 2013
Extraction max molars with inflammation – no difference Rood 1977 J Dent
Infiltration healthy canines – No difference Hobeich 2013 JOE
I&D procedure of 4% lido – Same for pain Harreld JOE Oct 2015
Double blind test of onset IAN block and long buccal – Same for pain Comerci Gen Dent 2015 Nov
Buffered articaine and others
Local infiltration lower molar – Pain same, onset same, length anesthesia same, success same statistically (although was 71v65%) JOE Shurtz Sept 2015
How mix your own buffered dental anesthetic
.7ml 8.4% sodium bicarbonate and .3ml 2% lidocaine with 1:80,000 epinephrine inverted 5 times to mix will give you a buffered lidocaine solution. Saatchi JOE 2016