He succeeds former Chief Minister J Jayalalithaa as legislator of the city segment. The newly elected MLA was sworn-in as a member of the 15th Assembly by Speaker P Dhanapal in his office.
Dhinakaran's supporters, including some disqualified MLAs and key aides like Thangatamilselvan and P Vetrivel, were present on the occasion. Dhanapal later shook hands with Dhinakaran.
The bypoll was necessitated due to the death of Jayalalithaa who was the sitting MLA. Dhinakaran trounced his nearest AIADMK rival E Madhusudhanan by over 40,000 votes.
Sidelined by the ruling camp a few months ago, Dhinakaran contested as an independent candidate from the constituency.