You are here:

Dentistry/Retained cotton pellet


Dr Kaurani,

About 10 years ago I had a crown placed on tooth #31 and subsequently needed a root canal through the crown (within 3 weeks).  The endodontist placed a temporary filling and I returned to my dentist for a permanent filling.  This past week the crown became loose and when my current dentist removed it he found the cotton pellet placed by the endodontist was not removed when the permanent filling was placed.  My dentist was shocked to see the retained cotton and mentioned that it was not "standard of care" to leave the cotton and it may have led to the significant decay found under the crown.  The tooth required a post, a build up and a new crown.  
I called my previous dentist to ask her opinion. She stated that because the tooth was "a closed system" after the crown was placed that the retained cotton was not the cause of any problem
So my questions are #1, was it inappropriate to leave the cotton pellet in before placing the permanent crown and #2, did the cotton lead to crown instability/ decay?
Thanks for your advice.

Dear rebecca
Its unfortunate to know that such a thing happened.

1) yes it was inappropriate to leave a cotton pellet behind
2) no the cotton itself cannot lead to further decay. The reason being the same " closed isolated environment with a permanent filling on top and crown encircling the tooth all around. If i may theorise further, one has to ask.... Why did you need an rct in the first place? Was it because of the nerve dying due to the crown placement procedure or was it due to leakage and decay around the crown margins?

A good starting point would be to evaluate the xray just before the rct was initiated through the crown.

My guess is (8/10 times) that the crown had leaking margins that caused the nerve of the tooth to die.

Best wishes
Dr mayank kaurani


All Answers

Answers by Expert:

Ask Experts


dr mayank kaurani BDS, MDS


rootcanals, cosmetic dentistry, dental pain, cavities, tooth colored fillings, endodontic diagnosis, post & cores, ceramic veneers, composite fillings, dental whitening, bleaching etc. please remember: i cannot treat you online and neither can i touch your teeth or test their health! i can give you general suggestions and critically evaluate various treatments and offer my advice.


14 years of clinical experience. i am a professor in a postgraduate dental school, in the department of endodontics. my primary field of specialization is in endodontics and conservative dentistry. i am a consultant endodontist in private dental clinics and run my own clinic restricted to conservative dentistry & endodontics since 2006.

DENTAL SPA, JAIPUR (INDIA). Mahatma Gandhi Dental College, jaipur(india)

new york state dental journal journal of contemporary dental practise

BDS, MDS (conservative dentistry & endodontics)

©2017 All rights reserved.