I'm not sure if there was more than one problem then I'm guessing you'd need more than one course of treatment. ???
Registering Charge Paying Adults for NHS treatment
The dentist is registering patients for NHS treatment, however, you pay eighty per cent of the cost of the treatment up to a maximum of £378 per course of treatment.
Registering Charge Exempt Adults for NHS treatment
The dentist is registering patients that are charge exempt for NHS treatment. To be exempt you are getting, or your partner gets, Income Support, Income-based Jobseeker's Allowance, Pension Credit Guarantee Credit, you are entitled to, or named on, a valid NHS tax credit exemption certificate, or you are named on a valid NHS certificate for full help with health costs (HC2).