Good Day! Apologise for not being able to comment on your interaction with the said dentist. Since you mention it's a college clinic, you can always approach senior staff with your grievance.
As far as your question goes, a crown or any restoration which provides cuspal coverage like bonded onlays, are recommended in post RCT cases. This is because of a significant removal of dentin during root canal treatment. The second reason is, since you have no sensation on the tooth post RCT, the force exerted on the tooth can be higher than normal.
While there is no particular amount of time post RCT within which you need to get a crown, as early as possible is the best rule. This is so that the tooth doesn't fracture under occlusal forces which if it did would then may need extraction or treatment with post retained crowns, either of which either complicates treatment or worst results in loss of tooth.
Answered2016-12-26 10:46:29
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