Diagnosis of Dental Caries

DIAGNOSIS OF DENTAL CARIES

CARIES

Defined as the microbial disease of the calcified

tissue of teeth , characterized by

demineralization of inorganic portion and destruction of organic substance of the

tooth.

Why is diagnosis important?

Caries diagnosis and treatment has traditionally been limited to the detection and restoration of cavitated lesions.

Undoubtedly, unaffected teeth are superior to restored teeth. Therefore early detection of incipient caries and limitation of caries activity prior to significant tooth destruction are primary goals of an effective diagnosis and treatment programme

Cavitation is preceded by a lengthy period of subsurface demineralization that presents the dentist an opportunity to detect the disease and start preventive measures prior to the advent of significant tooth damage.

METHODS OF CARIES DETECTION

Visual examination Tactile examination Radiographs - conventional - digital - xeroradiography Fibre optic transillumination Laser fluorescence Electric resistance measurements Dyes ultrasonics

VISUAL INSPECTION

Can be direct or indirect Magnification loupes, Slides,

Temporary separation as adjuncts for better vision

VISUAL INSPECTION

Ekstrand criteria for presence or absence of occlusal caries

V0 – No/slight change in enamel translucency after prolonged air drying. V1 – opacity/discoloration distinctly visible on air drying. V2- opacity/discoloration distinctly visible without air drying. V3- local enamel breakdown in opaque or discolored enamel. V4- cavitation in opaque/discolored enamel

exposing dentine.

TACTILE EXAMINATION

Explorer and Floss –used for tactile examination of tooth.

Explorer can be of different varieties such as:

Right angle probe Back action probe Shepherd’s crook Cow horn with curved ends

Use is condemned at times…

Physical damage to intact surfaces Fracture and cavitation of incipient

lesions False catch due to mechanical binding which may be due to : shape of fissure sharpness of explorer force of application

RADIOGRAPHS

Conventional Radiographs Bite wing Radiography Intra Oral Periapical

Radiographs DIGITAL RADIOGRAPHY xeroradiography

Conventional radiographsMost frequently usedLimitations of conventional radiographs They present a 2-D image May cause overlapping of teeth due to

faulty angulation Failure to recognise the initial lesion.

•Digital radiography either with charge couple device or storage phosphor screen technology has been used presenting added advantages such as: •less radiation required •Image is immediately available•Image can be electronically transffered•Image may be enhanced.

xeroradiography

Xerographic copying Record images produced by diagnostic xrays

No wet processing Image formation is achieved by photoelectrostatic process and not by photochemical process as in conventional radiographs.

FIBER OPTIC TRANSILLUMINATION

Alternative for bite wingIn medicine since 1960sUsed for surgical retraction in dentistry, caries detection, calculus, soft tissue lesionsPrinciple of transillumination: is that there is different index of light transmission for decayed and sound tooth

FIBER-OPTICS

DIAGNOSTIC PROCEDURE

Advantages: Several angles- 3 D picture Fast; no processing Examiation is simple and

comfortable for the patient Non invasive

Limitations: It can be used only for

approximal surfaces

USE OF LASER FLUORESCENCE

PRINCIPLE

DIAGNODENT

Chairside, battery-powered quantitative diode laser fluorescence device 655nm light beam Changes assigned a numeric value, which is displayed on the monitor

Criteria to assess caries progression: 0-13 No caries 14-20 Enamel caries and preventive

care advised 21-30 dentine caries and preventive or operative care advised >30 operative care advised

ADVANTAGES:• Earlier detection of lesions is possible• Depth of lesion can be estimated to certain extent•Examination represents no danger to patient or operatorDISADVANTAGES:•The method does not differentiate between active and arrested caries•Does not differentiate between caries and developmental defects with low mineral content•Secondary caries associated with metal fillings can not be detected

DYES IN CARIES DETECTION

Widespread use in medicine, biology & dentistryDiscrimination & easy identification of objectsVarious dyes have been used in detection of enamel caries (calcein,zyglo ZL-22) , and

dentine caries(fuschin, acid red system,9-aminoacridine)

Carious enamel detection

Detection of carious dentine

ELECTRONIC RESISTANCE MEASUREMENTS

•The low conductance of the tooth is primarily caused by enamel . At locations where pore volume of enamel is larger ( which is due to formation of microscopic cavities) the electrical conductance increases.•Conductance of - inversely proportional to tooth Resistance•When a potential of less than 1 volt is applied resistance > 600,000 ohms – no caries resistance < 250,000 ohms- caries involving dentine

ULTRASONIC CARIES DETECTOR

• use of sound waves for detection•Velocity of sound on enamel surface have been found to b Vs= 3,143,121 m/s.•Comparing with radiographic and visual inspection it has been found that white spot lesions with no radiolucencies or radiolucencies confined to enamel

no detectable or weak surface echoesSites with visible cavitation and dentinal radiolucencies

echoes with substantial higher amplitude are produced.

METHODS USED BY DENTAL PRACTICE- BASED RESEARCH NETWORK( DPBRN) DENTISTS TO DIAGNOSE DENTAL CARIES

DPBRN --- Has a valuable mix of dental practices. It mainly comprises of dentist practitioner – investigators from five regions: 1. AL/MS (Alabama/Mississippi) 2. FL/GA ( Florida/Georgia) 3. MN (Minnesota) 4. PDA(permanent dental associate in oregon and washington) 5. SK (Denmark, Norway & Sweden)

OBJECTIVES: 1. To identify the methods that dentists in DPBRN use to diagnose dental caries. 2. Quantify their frequency of use. 3. Test the hypothesis that certain dentist and dental practice characteristics are significantly asssociated with their use.

METHODS AND MATERIALS

• participants in DPBRN were recruited through mass mailings to licensed dentists from participating regions. 522 dentists participated•As part of enrollment all participants completed an enrollment questionnaire about their practice characteristics and themselves.

•An “assessment of caries diagnosis and caries treatment” questionnaire was sent to DPBRN dentists who reported on their enrollment questionnaire that they perform at least some restorative dentistry.

Research included the use of various diagnostic methods: 1.dental radiographs 2. dental explorer 3. Air drying 4.magnification 5. Fibre-optic devices 6. Laser fluorescence

Variations in the frequency of their use were tested using Multivariate analysis and Boneferroni tests.

There is considerable variation in the methods used for diagnosing caries across DPBRN regions:

1. Use of dental explorer – AL/MS reported highest frequency(93%) - MN reported lowest frequency - Dentists in a SGP (90% vs 80%) and

those who perform caries risk assessment ( 94% vs 87%) use

explorer on occlusal surface on a greater percentage. 2. Use of radiographs to - ranged from 95% in FL/GA to 88% in MN diagnose proximal - dentists who provide higher percentage of

pt with individualized caries prevention use

radiographs on greater percentage. - positive association between no. of years

since dental school graduation and greater use of

radiographs

RESULTS

3. Use of laser fluorescence – FL/GA reported highest frequency (13%) thanOn occlusal surface AL/MS region(6%) -dentists with least no. of years since dental graduation to use laser fluorescence more often

4.Use of air drying - SK region reported higher frequency (84%) than PDA region(60%)

5.Using magnification - FL/GA (79%) reported higher frequency - Male dentists (61%) vs females (40%) 6. Use of FOTI - positive association b/w pt. receiving high percentage of pt. who receive individualized caries prevention and use of FOTI.

CONCLUSION

The use of specific diagnostic methods varied substantially.The DENTAL EXPLORER and RADIOGRAPHS are still most commonly used diagnostic methods