A Windsor dentist says she's seen an increase in children's tooth decay since the removal of fluoride from the city's drinking water three years ago.

Dr. Alexandria Meriano is a pediatric dentist who — like many health officials in the region — wants to see Windsor put fluoride back in its water supply.

"As pediatric dentists, we see the worst of the worst sort to speak," she said. "Anecdotally, I believe what I have seen is younger kids with bigger cavities. So, very young children with gross dental decay on teeth they barely have."

Dr. Alexandria Meriano

Dr. Alexandria Meriano is a pediatric dentist who - like many health officials in the region - wants to see Windsor put fluoride back in its water supply. (CBC News)

Meriano wasn't shocked at the results of a new study out of Alberta that shows an increase in tooth decay in Calgary school children since the municipality there stopped adding fluoride to drinking water in 2011.

The study compared Grade 2 students in Calgary to those in Edmonton, where fluoride is still in drinking water.

The number of cavities increased in both cities over the study period, but "it got worse in Calgary," according to the authors of the study that was published Wednesday in the journal Community Dentistry and Oral Epidemiology.

"Doesn't surprise me at all," Meriano said of the benefits of using fluoride. "It's been common knowledge in the dental community, certainly, since at least the 1950s when community water fluoridation was initiated."

Studying Windsor

The Windsor-Essex County Health Unit also wants to see the city reintroduce fluoride to its water, but there are no plans to revisit that discussion for another couple years.

Like in the Alberta study, the health unit expects to compare dental health results before and after Windsor stopped adding fluoride to its water. But officials need to wait until it has four or five years of data, according to Dr. Gary Kirk, the medical health officer for the health unit.

"We're not even seeking that anecdotal information. We look for good hard evidence," he told CBC News. "We will acquire the evidence at the right time to determine whether or not there's been a change and whether or not it's significant."

Hygienists in Windsor regularly go into schools to check for tooth decay, missing teeth and fillings among students. Once the health unit has enough data, officials say they will have a fair comparison to study the impact of eliminating fluoride.

Without predicting the outcome of such a study in Windsor, Kirk said any evidence showing increased tooth decay and the lack of fluoride would help the health unit in its call to restore fluoride in drinking water.

"We think that will bolster the argument to add fluoride into the water again," he said. "We think it will be timely to present something to city council as a piece of information to help them make the decision to [add] fluoride back in the water."

Not everyone agrees, including one group of residents from the Windsor region who have a long-standing campaign to keep fluoride out of municipal tap water. Fluoride Free Windsor was one of the loudest voices urging the city to remove fluoride.

But for Kirk, fluoride has been studied enough to determine its benefits to dental health.

"Fluoride is a safe and efficacious addition to the water supply to provide and promote better oral health," he said. "Our stance has been pretty much the same as it was in 2013 and in years before because we have not seen good, compelling evidence to the contrary."