The ethical considerations of an emergency referral

It was New Year's Day. My colleague, a pediatric dentist, received a message on her emergency line from the parent of a potential patient, who is not a patient of record. The potential patient is seen routinely by another dentist down the street from her office, and this dentist informed the parent that he was out of the office due to illness and referred her to my colleague. The potential patient had a partially avulsed and fractured tooth no. 7 with a pulpal exposure and needed emergency treatment. My colleague's office policy is to return emergency calls for patients of record within 1 hour; however, this seems to be a gray area because the potential patient was referred. What are the ethical considerations regarding this emergency referral?

Automated summary

This paragraph describes a pediatric dentist receiving a message on her emergency line from a parent of a potential patient who is not recorded in her patient records. The potential patient usually sees another dentist and was referred to my colleague. There are ethical considerations regarding this emergency referral.