"Mouthfuls of rotten teeth, like crooked tombstones, people with two or three teeth trying to chew steak, it's just dehumanising."
Dental care is free for children up until the age of 18 in New Zealand.
Yet dental health is consistently among the top three reasons Porirua children under the age of 5 are admitted to hospital for conditions which could have been avoided with earlier access to primary health care.
Work and Income has urgent dental treatment grants that generally pay up to $300.
But Hanna said that was only enough money to get a tooth extracted, making restorative treatments like a crown or a root canal well out of reach.
"It's cheaper to get rid of it. It's dreadful, but people are in such pain that they'll do that."
He was also critical of that money only being available for emergency treatment, meaning the patient reached the point of being in pain before accessing care.
The incoming Government has promised to increase the maximum grant for emergency oral care to $1000, which health spokesman Chris Hipkins said would go a long way to covering the actual cost of dental work.
An extra 20 full-service mobile dental clinics were also promised for hard-to-reach areas.
The Capital and Coast District Health Board runs a limited low income service, which people can access by phoning in each morning for an appointment.
A DHB spokesman said if there were no appointments available, the person's details were recorded in case there was a cancellation.
Wait times for the service are not recorded, but Hanna has seen patients who have had to wait as long as a month.
After prescribing a course of antibiotics and pain relief, Hanna said he often saw the same people again in two weeks needing more medication to get them through until they could get a dental appointment.
"The antibiotics just dampen down some of the infection, but they don't stop the fact that there's a great big hole there", he said.
Patients can also be referred to the DHB's wider dental and oral health service by a private dentist or GP. All referrals are assessed by a senior clinician and prioritised based on the patient's level of clinical need.
Hanna said he was "bending the rules" to try to secure hospital appointments for people who needed a lot of dental work, had hardly any money, and had other health issues.
"It's essentially writing a really strong, assertive advocacy letter for my patient to make sure they get care.
"That breaks my heart because there might be another doctor down the road who isn't as good as writing stroppy letters, whose patient in the same situation might not get access to care."
He said people were needing to take weeks off work because of severe pain, or pain medication made them drowsy making it unsafe for manual labour jobs.
Porirua mayor Anita Baker said a large proportion of people's budgets were being spent on meeting skyrocketing rental prices, which has led to poor health outcomes.
Ministry of Business, Innovation and Employment (MBIE) bond data shows the average rental price has risen by $200 in Porirua over the past five years.