Southeast Portland

Fluoride debate: Study looked at fluoride vs. non-fluoride in Portland area

Fluoride debate: Study looked at fluoride vs. non-fluoride in Portland area

PORTLAND, Ore. - In light of the contentious fluoridation vote in Portland this month, the KATU Problem Solvers continue to ask the question: is fluoridation working right now?  To help answer that question, I dug up a little-known study that evaluates this question right here in the Portland metro area.

Five years ago, Dr. Gerardo Maupomé of Indiana University published a study called “A Comparison of Dental Treatment Utilization and Costs by HMO Members Living in Fluoridated and Non-fluoridated Areas.” It was published by the American Association of Public Health Dentistry.

The study compared dental treatment and the associated costs for HMO members living in fluoridated and non-fluoridated areas from 1990 to 1995. The data came from Kaiser Permanente Northwest members living in the Portland metro area, Marion County, and Clark County, for a total of 51,683 people who all had insurance.

“The beauty of this (study) is you are really looking at a slice of reality,” said Maupomé via Skype.

Since Portlanders are voting on whether to add fluoride to their drinking water, we decided to pull out the numbers for the metro area. It included Multnomah and Clackamas Counties - which mostly are not fluoridated - and Washington County, which mostly is.  The researchers verified everyone's fluoridation status using their home addresses.

First, we looked at the number of dental visits for both the fluoridated and non-fluoridated groups. Again, all the people in this study were insured.

Estimated at different ages - 10, 39 and 80 - we found the number of dental visits was similar, with those in fluoridated areas going to the dentist slightly more. 

Number of Dental Visits - Portland Metro 1990-1995
  Non-fluoridated Fluoridated
Age 10 12.7 13.5
Age 39 14.3 14.9
Age 80 20.3 20.9

In Marion and Clark Counties, the numbers again were close, though people in non-fluoridated areas visited the dentist slightly more often.

So what did those dentists actually find in terms of cavities?  The youngest patients in the non-fluoridated metro area had about the same number of cavities as those in the fluoridated area. The same was true for the adults. 

Surprisingly, the biggest difference was in the elderly. Those in the non-fluoridated area had more cavities than their fluoridated counterparts. 

Avg. Number of Cavity Treatments - Portland Metro 1990-1995
  Non-fluoridated Fluoridated
Age 10 4.15 4.18
Age 39 6.61 6.46
Age 80 12.79 11.96

The Problem Solvers found similar results in Marion and Clark Counties.
 
We asked Maupomé if it was fair to say they didn’t find much difference in the number of cavities between non-fluoridated and fluoridated area, except in the oldest populations.

“It was more apparent in the oldest populations,” answered Maupomé.  “It was more apparent. That was primarily what we saw.”

But remember, this data is from people who have dental insurance, not uninsured kids.

One reason insured kids in non-fluoridated areas may be keeping up with fluoridated kids has to do with extra fluoride treatments from their dentists. The study shows 52% of kids ages 6 to 11 in non-fluoridated areas got topical treatments compared to only 22% of kids in fluoridated areas.  For kids ages 12 to 17 the results were similar.

We found consistent results in Marion and Clark Counties.
                  
So is that the way to go: topical fluoride treatments instead of fluoridated drinking water?  Maupomé contends fluoride treatments are more work and more money.

“You have to remember that these supplemental fluoride dispensings are benefiting a small group of the population,” said Maupomé, “and we already know from this data that the old folks are not going to get supplemental fluoride dispensings.”

Maupomé said the people who would benefit the most from drinking water fluoridation in our area are seniors, especially those who don't have insurance and want to keep their teeth, as well as uninsured kids and adults. 

For the rest of us, Maupomé said the benefit comes in lower public health costs.
  
Of course, fluoride opponents have a different view.

“We want activities and programs that work and are not a waste of taxpayers’ money,” said Rick North with the Clean Water Portland campaign.

North supports increasing access to dental care, preventative sealants, good oral health behaviors, and education about better nutrition as ways of addressing dental issues in low-income families. He also points to questions about the health effects from drinking water fluoridation.

The Problem Solvers contacted the Oregon Health Authority, the state agency in charge of oral health programs that strongly supports community-wide fluoridation, for its perspective on the Maupomé study.  The OHA declined to comment.

Last week, the Problem Solvers analyzed the raw data from OHA’s 2012 Smile Survey. Our analysis revealed little difference between the cavity rates of kids in fluoridated schools versus non-fluoridated schools:

  • 53.7% of the kids in the non-fluoridated areas had one or more cavities
  • 52.03% of kids in fluoridated areas had one or more cavities
  • 47.81% of kids in fluoride-free Portland water district had one or more cavities

Ballots on the fluoridation measure will be mailed to Portland voters on May 3.  Ballots are due May 21.

Read more: Full study - “A Comparison of Dental Treatment Utilization and Costs by HMO Members Living in Fluoridated and Non-fluoridated Areas”