England only... Maternity Medical exemption

Caroline 🇬🇧 • 25 years old. ♌ #1st Baby👶🏽 Born 4th Oct 2017 👨‍👩‍👧 From England 🇬🇧

I am wondering what is the procedure of seeing a dentist when having a medical exemption. Do i book an appointment with a dentist or do I need to get referred by my GP. FYI im not registered with a dentist. And when does the medical exemption run out after baby is born. *Baby is 4 weeks old*