Cariology Lecture 8

What does minimally invasive dental caries therapy do?

Selective caries removal

Biofilm management

Remineralization support

Patient-centered care

What is selective caries removal?

Remove only irreversibly damaged dentin while preserving affected tissue for minimally invasive care

What is biofilm management?

Use antimicrobial agents and probiotics to balance oral microbial communities and reduce caries

What is remineralization support?

Applying fluoride varnishes and other agents to promote natureal enamel and dentin repair

What is patient-centered care?

Tailor treatments to individuals needs to minimize discomfort and maximize therapeutic results

What are minimally invasive techniques?

Chemo mechanical caries removal that uses agents to soften infected dentin for gentle removal without damaging healthy tissue

What is CMCR?

Chemo-mechanical caries removal

What are common chemical agents used in CMCR?

Carisolv, Brix 3000, and Papacarie

Interface with denatured collagen to facilitate decay removal

What are patient comfort benefits associated with CMCR?

Reduces the need for anesthesia and is ideal for for children and anxious patients by minimizing discomfort

What is tooth structure preservation with CMCR?

Preserves healthy tooth structure better and lowers the risk of pulp exposure compared to traditional drilling

What is selective decayed tissue removal?

Polymer burns selectively remove soft, infected dentin while preserving healthy and remineralizable tissue

What is reduced pulp exposure risk?

Using polymer burns lowers the risk of pulp exposure and reduces the need for anesthesia during procedures

What is a minimally invasive design of self-limiting polymer burs?

These burs provide a tactile, pt friendly experience ideal for minimally invasive dental treatments

What is the clinical effectiveness of self-limiting polymer burs?

Clinical studies confirm polymer burs maintain tooth integrity and improve patient outcomes

What is stepwise caries removal?

Involves partial caries removal, temporary restoration, and final excavation after healing to protect pulp

What is selective caries removal?

Preserves carious tissue near the pulp to avoid exposure, ensuring a strong peripheral seal

What are pulp vitality guidelines for caries removal?

Both stepwise and selective methods aim to maintain pulp vitality and restoration longevity, following dental association guidelines

What should the approach for caries removal on permanent teeth be determined by?

The severity of the lesion

What is non-selective carious tissue removal?

Carious tissue being removed until hard dentin is reached, which also is known as complete caries removal

What is stepwise carious tissue removal?

Carious tissue being first removed until soft dentin is reached, followed by placement of a temporary restoration

What is two-step caries removal?

Months after treatment of vital, non-endodontically treated permanent teeth, the restoration and carious tissue are removed until firm dentin is reached and a permanent restoration is then placed

What are the practical implications of a more conservative caries removal approach?

CTR approaches may decrease the risk of adverse effects

What are direct restorative materials effective in treating?

Moderate and advanced caries lesions on vital, non-endodontically treated primary and permanent teeth

Assessment of patient factors

Evaluating patient risk, lesion depth, and oral health guides treatment decisions in minimally invasive dental care

Use of diagnostic technologies

Risk assessment tools and diagnostics help identify suitable candidates for minimally invasive treatments

Integration into clinical practice

Training, patient education, and evidence-based guidelines support effective MIDCT implementation

Balancing preservation and durability

Clinicians ensure optimal outcomes by preserving tooth structure while providing durable restorations

Challenges of MIDCT

Including high costs, limited accessibility, and the need for specialized clinician training

Limitations of techniques in MIDCT

Techniques like laser and air abrasion are not universally available and newer agents require clinician familiarity for effective use

Future research directions for MIDCT

Research should focus on improving materials, refining techniques, expanding access, and conducting clinical trains for efficacy and durability

Dentin sensitivity models: Capillary Flow Dynamics

Tubular fluid flow of 4-6mm/sec is produced by a stimulus that expands or contracts the tubular fluid volume and creates rapid shifts in the rate and direction of the fluid flow

An outward flow causes more sensation than does flow in pulpal direction. Air-drying, cold water rinses, or pressure from probing and cutting dentin, generate outward fluid displacement

The hydrostatic pressure displaces the odontoblastic cell bodies and stretches the terminal branches of the nerve plexus to allow the entry of sodium to initiate depolarization and the perception of pain

ATP released by stimulating endothelial cells, may provide a chemical rather than mechanical explanation for depolarization

ATP receptors have been intensifies on terminal branches of pulpal sensory neurons

Sensitivity models: Axon reflex

A painful stimulus-reflex response is protective as an alarm to avoid trauma or injury

The advantages of painful and sensitive dentin to foods and fluids are less clear, and pain is not a reliable indicator of histopathologic changes or of dentin demineralization caused by caries

It is possible that the major protective benefit of stimulating the sensory pulpal nerves is not the registering of pain in the central nervous system

Branches of these afferent nerves loop back via an axon reflex to stimulate the contractile components of the vascular complex

When triggered, they release potent neuropeptides to activate vasodilation, increase blood flow, and elevate interstitial pressure

Rather than discomfort, homeostasis and pulpal defense may be the critical protective outcomes of the hydrodynamic response

What is the formative function of dental pulp

Generates primary, secondary, and tertiary dentin (dentinogenesis)

What is the nutritive function of dental pulp?

Provides the vascular supply and ground substance transfer medium for metabolic functions and maintenance of cells and organic matrix

What is the sensory function of dental pulp?

Transmits afferent pain sensation (nociception)

What is the protective function of dental pulp?

Coordinates inflammatory, antigenic, neurogenic, and dentinogenic responses to injury and noxious stimuli

How is considerable physical, chemical, and thermal irritation of the pulp generated?

Mechanically cutting tooth structure, especially dentin, during restorative treatments

How can you decrease the chance of pulpal irritation or injury during restoration?

Maintaining a thick amount of remaining dental tissue

How can you protect the pulp from mechanical pulp exposure or use of acidic restorative materials?

Conservative dentin removal techniques and bacterial control (rubber dam)

What percentage of pulpal necrosis after a 5.5 degree temp increase?

15%

What percentage of pulpal necrosis after an 11 degree increase in temperature?

60%

Does crown prep without water coolant increase or decrease interpulpal temp?

Increase

Can cause necrosis

What is essential to avoid histopathologic damage during a crown prep?

Water coolant and intermittent rotary instrument contact with tooth structure

4 keys to minimizing adverse pulpal reaction from rotary instrumentation

Adequate air-water coolant spray

Light pressure

Sharp rotary cutting instruments

Preservation of tooth structure

Newer methods of tooth preparation that are also traumatic to the pulp

Lasers

Air abrasion

Electrosurgery to remove excess gingival tissue

4 causes of pulpal inflammation

Reaction to an irritant with an inflammatory response

Invasion by bacteria or their toxins

Early enamel caries lesions that extend less than ¼ of the way to the DEJ have been shown to induce an pulpal reaction due to an increase in the permeability of the enamel

Some dental materials

Cavity sealers

Provide a protective coating to the walls of the prepared cavity and a barrier to leakage at the interface of the restorative material and the walls

Cavity liners

Cement or resin coating of minimal thickness less than 0.5mm to achieve a physical barrier to a bacteria and their products and/or to provide a therapeutic effect, such as an antibacterial or pulpal anodyne effect. Usually only applied only to dentin cavity walls that are near the pulp

Cavity bases

Materials to replace missing dentin

Used for bulk buildup and/or for blocking out undercuts in preparation for indirect restorations

What is varnish?

A natural gum, rosin, or synthetic resin dissolved in an organic solvent such as acetone, chloroform or ether, that evaporates, leaving behind a protective film, usually 2-5 microns

Coral varnishes were used for many years to fill the gap at the amalgam-tooth interface until corrosion products formed to reduce the gap

Is there a decrease in postop sensitivity with the use of adhesive agents under amalgam restorations?

Not according to numerous studies

Calcium hydroxide

Long uses as a liner bc of its pulpal compatibility and purported ability to stimulate reparative dentin formation with direct pulpal contact by its antibacterial action and may release growth factors that can assist pulpal healing

Highly soluble and is recommended to apply only over the smallest area that would aid in the formation of reparative dentin

Why is glass ionomer a desirable cavity liner?

Chemical bond to tooth structure and fluoride release

Is fluoride release sustained over time in glass ionomer?

It decreases over time

Sustained release has been demonstrated with corresponding uptake into adjacent tooth structure

When are visible light-activated formulations of glass ionomer desirable?

With resin composite restorations due to improved resistance to acid solubility while maintaining fluoride release and bond to tooth structure

Zinc oxide-eugenol and zinc phosphate cements

Provide excellent thermal insulation

Use has diminished with the advent of material that release fluoride and adhere to dentin

What can be used as bases and cavity liners?

Glass ionomer

Excellent mechanical properties, modules of elasticity, and restorative support as well

Guidelines for basing, lining, and sealing

Do not remove sound tooth structure to provide space for a base

Use vases as indicated for buildup materials for cemented indirect restorations

Use minimum thickness of liner to achieve the desired result, less than 0.5mm

What must a tooth have to have for direct pulp capping?

A vital pulp and no history of spontaneous pain

Pain during pulp testing with hot or cold should not linger after stimulus is removed

A periapical radiograph should show no evidence of a periradicular lesion of endodontic origin

Bacteria must be excluded from the site by the restoration

When should indirect pulp capping be considered?

When there is a radiographically or clinically evident deep caries lesion encroaching on pulp and the tooth has no history of spontaneous pain and responds normally to vitality test