Problem with sealants?

A few years ago I lost my dental insurance. I had sealants put on my back teeth to prevent cavities since I knew I wouldn't be visiting the dentist regularly. Now it turns out that there is a "defect" in one of the sealants and I have a cavity back there. Is this normal, or a mistake by the dentist who put in my sealants? Should my sealant doctor pay for the cavity and fixing the defect?
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Sealants are basically a thin layer of material that fill in the deep groves on the top surfaces of your molars. By having sealants they help bacteria from becoming trapped in spaces your toothbrush can't reach. Sadly, they do not last forever for most people. After time and wear, like anything, they begin to break down and slowly chip away causing more crevices to trap bacteria which leads to decay. I'd love to jump on the band wagon and try to get a free filling done at the expense of the dentist but truth be told, they are a preventative measure and I'm glad you had them done because you probably would have had more cavities a lot sooner but you were smart enough to have them done. So my answer is yes, this is a normal thing. They're just there to help prevent cavities but they are not a permanent restoration type of thing. Make sure your home-care is top notch too since your out of dental insurance and scrub those teeth well, even where the sealants were placed. And flossing will prevent cavities from forming in between your teeth because there is no type of sealants to prevent decay there. It's all up to you. So take care. :)
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