13 the white spot lesion

13 the white spot lesion
Lama K El Banna

1. The White Spot Lesion Dr. Ahmed AlShawi

2. "Dental caries is a specific and treatable bacterial infection due to mutans  streptococcus (MS) and in the later stages to lactobacillus.” Currently beginning to believe that while MS is still important, lactobacillus  and other acid producing bacteria are also initially involved .   "The development of dental caries is a dynamic process of demineralization of  the dental hard tissues by the products of bacterial metabolism, alternating with periods of remineralization. ”

3. Caries is a multifactorial process ( Host Factors , Specific Bacteria , Sugar and time ) and is  reversible in the early stages .    P it and fissure caries is the most common. Glass et al (Caries Res, 1983)   Children between 6-30 months may become infected by salivary exchange with the mother.  Presence of caries in the mother increases risk of the child .   Evidence indicates that not only is dental caries increasing in the low income population but also in middle and higher income children and teenagers.

4. Since dental caries is an infectious disease, a review of terms and concepts associated with the epidemiology of infectious diseases are listed: For an infectious disease to occur, it must have a  source or reservoir  (person, animal, soil).  In dental caries the source may be the mother who transfers the infection to the infant. Potential microorganisms may be transferred directly (by people, insects) or indirectly (through water, air or soil).  In dental caries the transfer agent is through saliva of the mother to the infant. Pathogens must survive during  transfer and successfully establish within the host . In dental caries, this will take several attempts and only at specified time periods .

5. Colonization (multiplication of the organism) may occur without evoking a tissue or immune response .  In dental caries this occurs .  Additionally, colonization and bacterial multiplication in dental caries is dependent upon sugar intake and other local factors. Infection indicates that colonization has occurred and the disease process has begun as indicated by damage to the tissue.  In dental caries, there is demineralization of the tooth surface. The host response will determine if there is a manifestation of the disease (demineralization).  If the host response is adequate, the individual may have the infection without the clinical manifestations of the disease.  He/she may thus be a carrier, harboring the infectious agent which can be spread to others.  In dental caries, the carrier would usually be the mother. 

6. The  surface of enamel is dynamic  and in a constant state of flux depending on the microbial and chemical consistency of saliva and plaque.      Changes in these environments (saliva and plaque) can either have a detrimental or beneficial affect on the enamel surface.  The detrimental affect can be identified as the early, reversible event in dental caries, the white spot lesion .     The early observation and clinical evaluation of white spot lesions on the tooth surface provide the dentist with important information about the disease process (active or inactive).    

7. 1. Intact block showing enamel surface and sub-surface

8. 2. Beginning of  direct enamel surface crystal dissolution along with subsurface dissolution (demineralization )  creates pores in the enamel.   This results in surface roughness and loss of surface shine (Change in optical behavior).

9. 3.  Enamel demineralization alters the optical behavior of the enamel resulting in greater visual enamel opaqueness since porous enamel scatters the light more than does sound enamel ( 1 )  A lesion  requiring air-drying to become visible (opaque) has lost less mineral than a lesion which is visible without being air-dried.  (2 ) The histological examination of ground sections confirmed a  higher level of porosities and deeper penetration of the lesion into the enamel in lesions visible without being air-dried compared with lesions visible only after being air-dried.

10. 4. As demineralization progresses,  the pores increase and with remineralization the pores decrease .

11. 5. As the  pores enlarge bacteria may invade the subsurface.   It is somewhere during these stages of the demineralization process that the white spot lesion will lose its potential for remineralization.

12. 6. In the final stage, the carious process has progressed to the point where sufficient amount of enamel matrix has been lost and the inward collapse of the remaining surface layer.

13. Loss of remineralization ability may be due to: 1. Destruction of the enamel matrix . 2. Alterations in the acid diffusion pattern into the subsurface resulting in lower pH . 3. Bacterial invasion into the subsurface.

14. The best indicators for an increased risk of dental caries infection: Most consistent predictor in children is past caries experience . Presence of caries in the mother . Oral hygiene status ,  Fluoride intake . Medical conditions-- low salivary flow levels . MS  levels are weakly predictive .

15. Measuring the  MS  levels at suspected sites has use in determining current caries activity .   -A commercially available  MS  test ,  the Dentocult SM chair-side testing kit is available.  It has limited accuracy.   The most reliable  MS  test is available through bacteriological testing labs. Levels  exceeding 100,000 CFU suggest that caries is active.  Knowing  MS  levels is an aid for caries assessment and monitoring.     With the white spot lesion, we observe physical changes that occur at the tooth surface, providing information about the status of caries activity at a specific site.  Use color and texture to access the disease state.  Texture is more reliable than color .  

16. he disappearance of white spots (WS) can be by remineralization and surface   abrasion (1). The repair process:      - Demonstrated by in vivo studies (2).      -Low fluoride levels enhances rate and degree of remineralization (1,3).      - Remineralized enamel is more resistance to caries attack (more acid insoluble) than intact enamel (4).      -Repaired enamel has greater organic content which helps resist acid attack (4).

17. In a adult human study (1966) 71 WS lesions were tracked for 7 years with the following results:     -9 lesions progressed to caries. (13%)     -25 lesions remained unchanged. (35%)     -37lesions where no longer detectable (5).  (52 %) In 12 year old children (2003) 719 WS lesions were tracked for 36 months with the following results:     -177 lesions progressed to caries. (25%)     -397 lesions remained unchanged. (55%)     -145 lesions where no longer detectable (6). (20%)

18. Diagnosing and Differentiating Between Active and Inactive lesions. The white spot (WS) lesion can be active progressing to cavitation, it may be inactive not progressing or may even be healing Sound Enamel    Smooth surface  intact, smooth and glossy.  Pit and fissures   intact possibly with some staining. 

19. Enamel hypoplasia Enamel hypocalcification Enamel hypoplasia  is a defect in tooth enamel matrix formation that results in less quantity of enamel than normal.  May be pitted and rough if severe . Enamel hypocalcification  is a deficiency in mineral content and appearing to have a normal enamel matrix.  This may be difficult at times to differentiate from WS lesion. 

20. White spot lesion  Active caries  (chalky surface) Surface of enamel is whitish/yellowish  opaque with loss ofluster .   It  feels  rough  when the tip of the probe is gently moved across the surface.   No clinicallydetectable   loss of substance. Smooth surface  caries lesion typically located close to gingival margin.  Pit and fissures have intact fissure morphology .  Lesion may extend along the walls of the fissure.  Under proper conditions, non- cavitated areas can remineralize and converted into arrested or nonactive lesions (1). 

21. White spot Inactive caries Surface of enamel is  white, brown or black .  It is   glossy with no   loss of luster; feels smooth and hard  when the tip of the probe is  gently  moved across the surface (2).   The root/dentin lesion  is hard and may be dark.

22. Cavitated lesion,  active caries. Enamel/dentin cavity easily visible with the naked eye;surface of cavity feels soft or leathery on gentle probing.  There   may or may not be pulpal involvement.   The lesion is usually moist and grayish.         

23. Cavitated lesion, inactive caries Enamel/dentin cavity easily visible with the naked eye;  surface of cavity feels hard on gentle probing, appears shiny and may have dark stain.             

24. Classification Description Intact restoration.    Intact restoration. Restoration with active caries. Secondary caries lesion may cavitated and/or have active white spot lesion area adjacent to restoration.  White spot area is rough to the feel and is not glossy.     Restoration with inactive caries. Secondary caries lesion may cavitated and/ orhave inactive white spot  lesion area adjacent to restoration.  White spot area is smooth to the feel and is glossy.                                                                                                            

25. 1. FOR VISUAL IDENTIFICATION OF THE LESION

26. Use a good light. Clean and dry the teeth. Magnification helps. Transillumination helps. uses light to transilluminate each tooth and to instantly create a digital images of the tooth on a computer monitor . Dyes are of limited use. Diagnodent : Tooth structure will fluoresce when irradiated by a laser light of a specific wavelength. The presence of dental caries alters the fluorescence of the tooth structure. These fluorescence changes are measured by this instrument and are used as an indicator of the extent of caries .

27. 2. Tactile- use of explorer?  

28. 3. X-rays help especially for proximal lesions.  Use digital x-rays.

29. STRATEGIES TO FOLLOW FOR CARIES CONTROL:

30. Identify the individuals at risk.      Do a risk assessment. Control the  MS  infection.  At the initial office visits provide 1.2% Acidulated- Phospo - Fluoride (APF) treatment. Have the patient use 1/2 oz. Chlorhexidine mouth rinse for 30 seconds at bedtime for 2-3 weeks. Apply   fluoride varnish. In high risk individuals also have patient use 1.1% NaF ( Prevident 5000) paste. Have patient use Xylitol gum, 2 pieces, 5 times per day, for 5 minutes. Stress control of sugar intake. Monitor oral hygiene. Pit and fissure sealants may be used in the high risk patient to eliminate sites that could harbor  MS  in large numbers. Use hard cheese in diet. Casein presence aids in remineralization.         -Also suggested for the control of  MS  infection is the use of an ozone producing device to eliminate bacteria and the use Povidone Iodine as a topical agent on teeth.

31. These procedures initiate measures to shift the patient at high or moderate risk to low-risk category.  It will also aid in treating the non- cavitated lesions to remineralize.    Cavitated lesions are treated in the traditional fashion. Monitor caries risk status of patient at recalls   to maintain-low risk category.

32. Summary: Dental caries is an infectious disease caused by specific acid producing bacteria found in the biofilm.    Dental caries is a reversible, multifactorial process of tooth demineralization and remineralization.   Cavitation is the terminal,  non-reversible end of the disease process.   The cavitated lesion can only be treated by restorative means.   The disease process begins with the concentration of  MS  and other acid producing bacteria in the biofilm at specified tooth surfaces and may  lead to white spot formation or even cavitation.   The disease progression may be sporadic and can terminate at any point in the process.    The white spot is treatable by non-invasive means, can be maintained in an inactive form or even  heal, if the lesion is non- cavitated and the cariogenic bacteria, diet factors and host factors are maintained at a low level.