Incipient caries and Remineralization

Dr. Eszter Varga Department of Conservative Dentistry

Definition of caries 1.

• multifactorial • irreversibel disease of calcified tissues of teeth • demineralization of the inorganic substance • destruction of the organic substance • leads to cavitation

Definition of caries 2.

• dynamic process • imbalance between demineralization and remineralization of the dental surface • potential to remineralize incipient lesion! (reversibel)

Etiology of caries

Host Caries Plaque, micro- organisms Diet Time

the major virulence factors of S.mutans

• acid production (acidogenicity) • acid tolerance (aciduricity) • intracellular polysaccharide synthesis (storage of carbohydrates) • extracellular polysaccharide synthesis (increases adhesion) • ability to adhere to other bacteria and tooth surface

Host (Saliva)

• Cleaning • Buffering • Antimicrobal effect (lysozyme, laktoferrin, lactoperoxidase) • Normal vehicle for calcium, phosphat

Salivary disfunction

Poor salivary flow: (high caries risk) – hypertensive drugs,diuretics – systemic diseases • Sjogren-syndrome, Diabetes mellitus, diseases of salivary glands – head and neck cancer treatment

Host(tooth)

• tooth morphology • irregularities in arch form crowding ,overlapping • tooth composition mineralization, fluorid

Carbohydrates

• Physical form • Chemical composition • texture of food • frequency of ingestion • presence of other food constituents

Enamel

• Most mineralized, very hard, thin translucent layer • Inorganic materials – 95% calcium and phosphate (hydroxiapatit crystals) Ca 10 (PO 4 ) 6 OH 2 – Trace minerals in crystal lattice (change the solubility of enamel) • Fluorid, carbonate • Sodium, zinc, strontium, potassium • Organic materials (1-2%) – Enamelins • Water 4%

• Rods, rod sheath, interrod enamel • Pores (enamel permeability!) – Fluid movement, diffusion – Variation of density and hardness

Enamel

• • Primary contact with cariogenic bacteria Begin of demineralisation process

• Pellicula • Plaque formation • High bacterial metabolic activity – (carbohydrates→organic acids) – S.mutans,Lactobacillus acidophilus, Actinomyces • pH drop • demineralization

• Incipient carious lesion (earliest phase of tooth decay) • Capable of being reversed, arrested or progressing to cavitation

Demineralization Remineralization • when sugar present demin. rapidly occurs • between sugar episods remin. slowly occurs • if remin. periods exceeds demin. periods subsurface lesion will mineralize • if demin. periods exceed remin. cavitation will occur • demin. periods exceed remin. periods when sugar is frequent or prolonged

Histology of incipient caries

light microscope polarized light microscope • surface zone • body of the lesion • dark zone • translucent zone

Diagnostic methods

• Clinical-visual method – Sharp eyes and magnification • Alternativ – X-rays – FOTI, QLF – Laserfluorescence – ECM, electrical impedance measurement – Ultrasonic caries detector

Clinical characteristics of incipient lesion • Colour (white, brown) • Opacity, translucency • surface texture • surface hardness ! Fragile surface layer,damage from probing!

Common sites of occurence

• Cervical third of a tooth • Pits and fissures • Vestibular tooth surfaces after orthodontic treatment with multibonded appliances • Cervical margins (in patients with prosthodontic restorations)

Treatment

• Preventiv,nonsurgical treatment • Monitoring Depending on risk level, oral hygiene , diet management, motivation, fluorid, fissure sealing

Prevention 1.

Maintain an oral enviroment that prevent demineralisation and enhances remineralisation • oral hygiene • diet management • fluorid • fissure sealing

Treatment

• limit susbstrate (diet management) • modify microflora • chlorhexidine, triclosan • prevent plaque succession • plaque removal (oral hygiene) • modify tooth surface fluorides (increas resistance) • stimulate saliva flow sugarless chewing gum noncariogenic foods that require lots of chewing

Diet management

• Reduce number, duration and intensity of acid attacks • reduce or eliminate sucrose from meals, eliminate from between-meal snacks • consume all sweets in one episod preferably following a meal

Effects of fluoride

• Enhances the remineralization (precipitation into tooth structures) • more acid resistant enamel • antimicrobal activity