Authorities say a pair of crooked Pennsylvania dental office employees ran an after-hours, word-of-mouth operation where they performed root canals, pulled teeth and installed braces without proper training.

Montgomery County prosecutors say they've identified three patients who received treatment from the impostors, but X-rays indicate there could be dozens more.

A grand jury report alleges dental assistant Cheryl Laing, 45, and receptionist Jessica Gullickson, 24, used the Bryn Mawr dental practice where they worked to provide low-cost services to uninsured patients.

One patient reported a tooth extraction was a painful 45-minute ordeal, and another said the receptionist was left to "find the root" during a root canal.

Both women were arraigned Monday on charges including theft and conspiracy. Phone listings for them couldn't be located Tuesday.