How to get replies to a twitter post



I need to calculate the average replies of my top 10 recent post from twitter.
But the api does not give me the replies to the post in the response.

I currently use the statuses/mentions_timeline and process the replies by comparing the id of the post with the response from the api.
This solution does not give me the correct reply count.

Is there any other way to do this?

Kindly help.