No, anyone is able to attend an appointment with a child as long as they fully understand what they will be signing and the responsibility they are assuming by doing so.

The 'patient declaration' / 'Completion of form guidance - FP17 / FP17O' states: "All Patients must read and sign this before NHS dental services are provided. This may be signed and dated contemporaneously by the patient's representative, as long as this is someone who is not connected with the dental practice".