Dental caries – Decay – Cavity – Cavities

Dental caries is the name of a disease resulting from ecologic shift within the dental biofilm that we maintain with frequent consumption of fermentable dietary carbohydrates. This results in an imbalance between demineralization and remineralization and eventually in the loss of dental hard tissue.

Nice image showing the dental decay between teeth once a dentist opens it up.

What is dental caries?

The definition of dental caries involves the feeding of the biofilm and resulting loss of mineralization from the acidic byproducts the bacteria produce. Therefore, decay is not an infectious disease that we “cure” by removing bacteria or especially any one species of bacteria. Instead we manage the disease behaviorally by reducing carbohydrates and removing dental biofilms. The 2016 consensus paper is the best piece of dental caries literature I have ever seen.

When should we fill a dental cavity?

We fill a tooth when there is surface cavitation that is noncleansable, however other factors like caries risk and lesion depth radiographically play a role. Overall dentists intervene too early and a more conservative approach should be taken by many. Caries Res 2018 Laske Opdam

Decay identification methods

Primarily dentists use visual cues and x-rays to identify decay. We also use tactile senses with the aid of an explorer. Decay can often hide on x-rays due to previous restorations, especially those containing metal or zirconia.

The angle of the x-ray can hide decay such as this btw that shows no decay but the PA shows decay.

Guidelines to the removal of dental caries.

• Preserve nondeminerailzed and remineralizable tissue.
• Create a situation that allows a seal on solid dentin or enamel
• Avoid pain and anxiety.
• Maintain pulpal health, even that means leaving soft dentine over the pulp
• Remove enough soft dentine that the restoration is durable.

The last two need to have a balance against each other.

Methods of decay removal

Nonselective removal to hard dentine or complete caries removal is now considered overtreatment and no longer advocated.

Fluoride

Fluoride is good for prevention not good once decay starts – B. Novy

• RCT shows 5000ppm good for root caries Yeung 2014
• 1° prevention root caries 38% Silver Diamine Fluoride professionally applied annually, 2° prevention of root caries 22,500 ppm Sodium Fluoride varnish professionally applied q3 months Gluzman 2013
• Meta-analysis 5,000 ppm F- and professionally applied CHX or SDF varnish may inactivate existing and/or reduce the initiation of RCLs. Hayes EBD 2015
• Meta-analysis – Fluoride varnish reverses incipient lesions.  Gels need for research. Lenzi JADA 2012
• Fluoride gel is good at prevention EBD Derek Richards 2015
• Adult patients that receive fluoride have significantly lower number of extractions and restorations than those that do not. This is from a study of nearly 700,000 people. The downside to this study is almost certainly some significant selection bias. Jackson JADA 2023
• Cochrane Review – Fluoride mouthwash prevents decay in children 2016

CPP-ACP

• No help when used for 1 year with fluoride in high risk kids (although I’m certain you can not trust people to do this on their own as this study did – would have been better if they had teacher do this every morning on the kids so know it was being done – If they were just given these products and instructions and the the results followed this was more a study on compliance than products IMHO) Sitthisettapong 2012
• Use after fluoride toothpaste is best way to use (didn’t test with both mixed together = CPP-ACPF) Kumar 2008

CPP-ACP with fluoride

• Puts more fluoride into the plaque than any other single or combo Reynolds 2008
• Flouride and calcium uptake is higher with varnish (although I think this study simply shows that it releases more when acid is added for 15 seconds and the rest is assumed – it could be argued it creates weaker substance that is broken down more readily) Schemehorn 2011

SDF silver diamine fluoride

This stuff is the best product available for arresting caries but turns black!

• Meta-analysis SDF effective in arresting caries among children EBD Richards 2017
• Meta-analysis SDF best treatment for caries in primary teeth EDB Seifo 2018 
• Meta-analysis SDF good for root caries. EBD McReynolds 2018
• SDF is almost certainly going to be a key to fighting radiation caries as well. BDJ 2023 Deepanjali

CHX or Chlorhexidine

• Meta-analysis 5,000 ppm F- and professionally applied CHX or SDF varnish may inactivate existing and/or reduce the initiation of RCLs. Hayes EBD 2015
• CHX gels and varnishes lack evidence of reducing caries Richards EBD 2015
• Chlorhexidine mouthwash more effective than gels and varnishes Richards EBD 2015
• CHX mouthwash w/ or w/o alcohol reduce decay Jose BJD Aug 2015

Carbamide peroxide

Xylitol

• Cochrane review says evidence insufficient at this point Riley 2015
• Xylitol added to fluoride toothpaste has insufficient evidecne to recommend over traditional fluoride toothpaste Lit review of RCTs Duane EBD 2015
• It has no effect on early non-cavitated lesions Brown Jun 2015
• Xylitol has big effect on root caries My blog post