Is Kolhan University as good as Vananchal Dental College and Hospital for BDS?

Yes, there may be a bond of admission at Vananchal Dental College and Hospital, and if you leave the institute after 1 or 2 years, you might be required to pay a penalty or complete a service obligation depending on the terms of the bond and your admission category (like management quota). Although the institute has not explicitly mentioned any information regarding the bond. You can contact the institute to get information regarding the same or refer to the official admission prospectus of Vananchal Dental College to see if a bond is explicitly mentioned and what the terms are regarding leaving the course early. Private colleges genreally have a stong and strict bond especially  for students admitted under the management quota.