Kathe Atkinson still gets random, shooting pain down the side of her face — three years after visiting a Surrey, B.C., dentist for cosmetic work.

"I wanted to have whiter teeth. I wanted to have a nice smile. And this is what it's gotten me — pain," says Atkinson, tears welling up in her eyes.

Atkinson is one of eight patients suing the same dentist, alleging everything from poor treatment to unnecessary procedures and overbilling. (Jacy Schindel/CBC )

Atkinson's teeth had a yellow tinge, which she says was due to excessive fluoride in the water she drank as a child in Paraguay.

She went to see Dr. Steven Krieger at Clover Care Dental Clinic, but instead of just bonding four of her teeth to make them whiter, he suggested she return to have three mercury fillings replaced.

Atkinson had the dental work done at Clover Care Dental Clinic in Surrey, B.C. (CBC)

That work was completed at one appointment, during which Krieger also had to rebond two teeth that were no whiter after his initial treatment.

Weeks later, Atkinson says, she was still in agony from the drilling.

"My whole side of my face — I had shooting pain up, shooting pain down, into my ear … I just kept popping Advil, Advil, Advil!

"It was excruciating, the pain," she says.

No longer trusting Krieger to work on her mouth, Atkinson visited other dentists in the hopes of alleviating her pain.

She wound up having three root canals, two crowns and additional surgery, but none of it brought relief so she eventually had the three teeth Krieger initially worked on extracted.

Atkinson filed a letter of complaint with the College of Dental Surgeons of British Columbia, and is suing her former dentist in B.C. Supreme Court.

Dentist Steven Krieger declined to be interviewed by Go Public regarding complaints from former patients. (Denis Dossman/CBC)

Krieger declined to speak with Go Public, but in his statement of defence filed in Atkinson's lawsuit says he "denies each and every allegation," including that he drilled too hard and too deep.

He says he treated Atkinson with "reasonable care, skill and diligence."

Krieger also denies that Atkinson "suffered or continues to suffer any injury" and that if she did suffer injury, it was her responsibility for, among other things, "not taking reasonable care for her own dental health."

"I don't know how he can actually deny it," says Atkinson.

"The pain started the day he worked on me, and it hasn't ended."

Dentist had history of complaints

Go Public has learned that another dentist complained about Krieger's work on more than two dozen other patients.

That dentist took over a practice Krieger ran in 2008, and took his concerns to the College of Dental Surgeons of B.C. in 2009.

He submitted detailed chart notes, X-rays and treatment outcomes for 28 patients, because he was concerned about what he saw, from fillings and crowns he considered done poorly, to unnecessary treatments.

Two of those former patients filed lawsuits, alleging poor treatment resulting in pain.

The cases were settled out of court, which does not necessarily mean there was a finding of wrongdoing.

8 former patients suing dentist

Today, Atkinson is one of eight patients suing Krieger, alleging everything from poor treatment to unnecessary treatment and overbilling.

Vancouver lawyer Dianna Robertson says the College of Dental Surgeons of B.C. needs to be more transparent. (CBC)

"The treatments that my clients underwent were basic dentistry," says Vancouver lawyer Dianna Robertson, who is representing six of those complainants.

"They weren't cutting edge, cosmetic, full mouth makeovers, or anything like that. So it's our view that any competent dentist would not have so many failures with so many patients."

It's not known whether the College of Dental Surgeons of B.C. ordered any retraining or other disciplinary measures after Krieger was investigated in 2009 — nothing is mentioned in the dentist directory on the regulatory body's website.

After receiving Atkinson's complaint, the college sent her a letter saying it had "competency concerns" about Krieger.

The letter says the college ordered him to take an "extensive educational program," and to complete two mentorships under other dentists.

It also said it was monitoring his practice for 30 months, periodically conducting chart reviews to assess his performance.

But the public wouldn't know because while Atkinson got the letter, none of those disciplinary measures is mentioned on the college's website.

College under fire

The college says its website was designed in part to protect the public.

The college receives hundreds of complaints about dentists each year, but only names names when a "serious matter" is confirmed — 16 since 2010.

It did not explain how the college determines whether a matter is "serious."

That's not enough transparency, says Robertson.

"Unless there is a very clear disciplinary action that usually would result in the person not being able to practice, it's not specified on the college site," the lawyer says.

"Even when the college provides a decision that shows the dentist's treatment was poor, the decision is provided to the person who complained, but it's not put on the website.

"So only that individual is now aware of the problem with the dentist."

The college website does say Krieger cannot perform root canals, but doesn't say why.

"That's certainly not very helpful to the public in trying to decipher why their dentist has a restriction," says Robertson.

When Go Public checked the website for Krieger's dental clinic, it still says he does root canals.

The website for Krieger's dental clinic says he does root canals, even though the province's dental college says he cannot do them.

The College of Dental Surgeons of B.C. declined an interview request from Go Public, saying no one was available.

Instead, it sent a statement saying, "When problems are exposed through the course of an investigation, our approach, wherever possible, is remedial [educational]."

It did not address why none of Krieger's "remedial" discipline is noted on its website.

More transparency in Ontario

Ontario passed sweeping changes to all 23 regulatory colleges in the province in 2014, requiring greater transparency to protect patient safety.

If the Royal College of Dental Surgeons of Ontario requires a dentist to take educational courses, a note is made on his or her record on the regulatory body's website, along with a fairly detailed explanation for the discipline.

Oral cautions are also noted, along with specifics of the allegations of misconduct, as are any criminal convictions.

"Any information where the college has concerns about a dentist's practice, we feel the public is entitled to know," says Irwin Fefergrad, registrar for the Royal College of Dental Surgeons of Ontario.

"It's important for the public to know that we're not putting something under the carpet, or shelving it," says Fefergrad.

'Mistakes kept out of sight'

Michael Decter, chair of the advocacy organization Patients Canada, applauds the changes in Ontario, saying the College of Dental Surgeons of B.C. is "a secret world of discipline where people's mistakes can be kept out of sight."

Michael Decter, of Patients Canada, says the College of Dental Surgeons of B.C. runs 'a secret world of discipline where people's mistakes can be kept out of sight.' (CBC)

"Patients should be able to go on a website and ask, 'Is there any issue with this dentist?' Not, 'Has this dentist been the subject of a formal disciplinary action?' But, 'Are there issues? Is this person on a watch list?'"

Decter says a large problem is often who sits on a regulatory college's board of directors.

"Patients should be able to go on a website and ask, 'Is there any issue with this dentist? Is this person on a watch list?'" -Michael Decter, Patients Canada

"Colleges say they're protecting the public," says Decter. "But the majority [of directors] are dentists, elected by dentists. How hard are they going to be on their colleagues?"

He points to the board of the College of Dental Surgeons of B.C., which has 12 dentists or certified dental assistants, and six members of the public.

B.C. health ministry responds

Go Public asked B.C. Health Minister Terry Lake for an interview to ask why the province's college for dentists isn't as transparent as those in some other provinces.

His office declined, sending a statement instead.

It said the "main goal" of disciplinary action is "to encourage ethical, competent practice."

It also said a working group on transparency for various health regulators is continuously "reviewing and considering ways to ensure high, fair, common standards of transparency."

Atkinson says while she waits for change, she also waits to one day be pain free, but she's not optimistic that day will come soon.

"I don't know," she says, tearing up. "I don't know. Three years later, the pain's not gone. I can't heal from it."

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