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Operative Dentistry - Best Practices

Caries Management:  Terminology

(last modified May 10, 2016)

Dental caries: Dental caries is the name of a disease resulting from an ecologic shift within the dental biofilm, from a balanced population of micro-organisms to an acidogenic, acidoduric and cariogenic microbiological population developed and maintained by frequent consumption of fermentable dietary carbohydrates The resulting activity shift in the biofilm is associated with an imbalance between de- and remineralisation leading to net mineral loss within dental hard tissues, the sign and symptom being a carious lesion .

Caries Process: is the dynamic sequence of biofilm-tooth interactions that can occur over time on and within a tooth surface. This process involves a shift in the balance between protective factors (that aid in remineralization) and destructive factors (that aid in demineralization) in favor of demineralization of the tooth structure over time. The process can be arrested and/or reversed at any time.

Caries lesion: A caries/carious lesion is a detectable change in the tooth structure that results from the biofilm-tooth interactions occurring due to the disease caries. It is the clinical manifestation (sign) of the caries process. ‘‘People have dental caries, teeth have caries lesions.’’

Terminology of caries lesion management, please see: Innes et al 2016 Advances in Dental Research 28(2):49-57.

Definitions of clinical presentations of Dentin and Figure from Innes et al 2016:

Soft Dentine:

Soft dentine will deform when a hard instrument is pressed onto it and can be easily scooped up (e.g., with a sharp hand excavator) with little force being required.

Leathery Dentine:

Although the dentine does not deform when an instrument is pressed onto it, leathery dentine can still be easily lifted without much force being required. There may be little difference between leathery and firm dentine, with leathery being a transition on the spectrum between soft and firm dentine.

Firm Dentine: 

Firm dentine is physically resistant to hand excavation, and some pressure needs to be exerted through an instrument to lift it.


Hard Dentine: 

For hard dentine, a pushing force needs to be used with a hard instrument to engage the dentine, and only a sharp cutting edge or a bur will lift it. A scratchy sound or “cri dentinaire” can be heard when a straight probe is taken across the dentine.










Demineralization (decalcification): Is the loss of mineral or calcified material from the tooth structure resulting from a chemical process that can be the result of bacteria metabolic products (caries) or chemical acidic products (erosion) from exogenous (diet, environment) or endogenous sources (gastric).

Cavitated Carious lesions: A caries lesion with a distinct breakdown of the surface integrity that can be detected using optical or tactile methods. This cavitated lesion can be confined in enamel or extended through to dentin. Once the enamel is cavitated the bacteria start penetrating dentin causing superficial tubular invasion. In a slow progressing caries lesion, different layers (infected and affected) of carious dentin have been reported in the cavitated lesion.

Infected dentinal carious lesion: is the irreversible demineralized and denatured layer with bacterial invasion. Very soft, moist and easy to remove with a spoon excavator.

Affected dentinal carious lesion: dentin is partially demineralized (leathery\softer than normal), collagen is not denatured and contains minimal to no bacteria.

Caries along DEJ: The presence and treatment of discoloration and stain along the DEJ is a current controversy and a point of discussion. Traditionally during operative procedures the removal of all stain and softness of the DEJ has been taught. Some histological studies have shown that staining and demineralization along the DEJ is not always related to bacterial infection (Kidd et al 1996).

Deep caries lesions: When caries lesion encroaches the vital pulp we recommend a conservative approach to caries removal in asymptomatic deep caries lesions.  Although some morphological studies have shown a defined boundary between the highly infected and the caries affected dentin, clinically this presents a subjective and difficult decision regarding the amount of dentin that should be excavated. Some studies (Larger et al., 2003) have shown that is not possible to eliminate all the micro-organisms even during a conventional caries removal, as a few bacteria will remain even after all soft dentin is removed. On the other hand, some studies (Ricketts & Kidd, 2006 systematic review), that have evaluated activity and progression of sealed lesions with remaining infected dentin, have shown that the majority of the lesions appeared to be arrested both clinically and radiographically and showed a decrease or absence in micro-organisms with time.