The School Dental Care Service website's services have been suspended after the leaking of personal information.
The Department of Health received a report on March 26 that other people's personal data appeared after a user logged in to the Student Internet Service.
The department quickly suspended the service.
A preliminary investigation found the incident may have been caused by a programme fault after the software was updated on March 23.
It is estimated the data of 210 primary school students may have been disclosed to other users from March 23 to 26.
The department is investigating the incident, has reported it to the Privacy Commissioner for Personal Data, and is contacting parents to apologise.
Parents can reschedule or cancel appointments by calling the School Dental Clinics or through the 24-hour clinic hotlines.
