Showing how to be minimally invasive in treating dental caries

1. MINIMALLY INVASIVE
CARIES THERAPY
Minimal intervention in operative dentistry
Minimal intervention dentistry [MI]
Minimally invasive operative care
Minimally invasive dentistry
Microdentistry
Dr. Osama H. Alkhalifa

2. DEFINITION AND ADVANTAGES
Definition:
conservation of a greater part of the
original, healthy tooth structure by
ultraconservative procedures.
Advantages:
1- repaired tooth will last a lifetime
2- less discomfort
3- less need for local anaesthesia

3. PRINCIPLES OF MI [FDI, 2000]
Control the disease through reduction of
cariogenic flora
Remineralize early lesions
Perform minimal intervention surgical
procedures
Repair rather than replace, defective
restorations

4. DETECTION OF CARIES
Visual Examination
Tactile Examination
Radiographic Examination
Fiberoptic Transillumination [FOTI]
Caries Detecting Dyes [CDD]
Electronic Caries Detector
Laser Fluorescence [LF]
Digital Imaging Fibero-Optic Transillumination
[DIFOTI]
Quantitative Light-induced Fluorescence [QLF]

5. DETECTION OF CARIES
VISUAL
 Teeth should be clean, dry and well illuminated.
 A white spot lesion that becomes visible only
after thorough air drying indicate that
demineralization will be less than halfway
through enamel.
 A white spot lesion visible on wet surface
indicates that demineralization is over halfway
through enamel, possibly extending into dentin.

6. DETECTION OF CARIES
TACTILE
G.V. Black 1924;
[A sharp explorer should be used with
some pressure and if a very slight pull is
required to remove it, the pit should be
marked for restoration even if there are no
signs of decay]

7. DETECTION OF CARIE
TACTILE
Probe does
not stick
“No caries”

8. Enamel
decalcification
Probe will now
stick
DETECTION OF CARIES
TACTILE

9. DETECTION OF CARIES
TACTILE
Explorer has been advocated for many
decades as important method to detect
caries, but research has shown this is to
be unwise practice.
Summitt 1996

10. DETECTION OF CARIES
TACTILE
Penning 1992;
Explorer detected fissure caries accurately only in
24% of cases.
Al-Sehaibani 1996
The reliability of carious lesion diagnosis by
sharp explorer compared to diagnosis of carious
lesion by histological cross section was 25%.

11. Fissure walls are
in close
apposition
Decalcification
A probe will be
unable to detect
caries here
DETECTION OF CARIES
TACTILE

12. Defects in the
fissure walls can
lead to dentin
caries with
NO enamel
decalcification
Can’t
diagnose
this with a
probe or
Caries
Detection
Dye (CDD)
DETECTION OF CARIES
TACTILE

13. DETECTION OF CARIES
TACTILE
Lussi 1993
A sticking probe is not necessarily indication
of decay and may be entirely to local
anatomic feature.
Ekstrand 1987
the explorer can damage white spot lesion by
breaking the relatively intact surface zone.

14. DETECTION OF CARIES
TACTILE
Graham Mount 2000;
[It is recommended that a blunt
explorer be used, only if necessary.
The probe must be used very lightly
on the side rather than the point. To
test the firmness and texture of tooth
surface.]

15. DETECTION OF CARIES
RADIOGRAPHIC
 Augments sensitivity of visual
examination.
 Bite wing radiographs are used to
detect proximal, occlusal and
recurrent caries

16. DETECTION OF CARIES
RADIOGRAPHIC
 Enamel lesions will not be visible on
occlusal surface in a radiograph, but it
can be visible on proximal surface.
 False positive can occur with
radiographic examination

17. DETECTION OF CARIES
COMBINED VISUAL & RADIOGRAPHIC EX.
Sensitivity will be 75% [25% false negative]
and specificity 90% [10% false positive]

18. DETECTION OF CARIES
FIBEROPTIC TRANSILLUMINATION [FOTI]
Detects caries on proximal surfaces
A bright fine light is transmitted through
contact point. Lesions appear as dark
shadow

19. DETECTION OF CARIES
CARIES DETECTING DYES [CDD]
Non-specific protein dyes that
stain the organic matrix of less
mineralized dentin.
They can stain carious enamel
by filling voids created by acid
attack.
Used for:
1- detection of occlusal caries
2- detection of carious dentin
during cavity preparation

20. DETECTION OF CARIES
ELECTRONIC CARIES DETECTOR
ELECTRICAL CODUCTANCE MEASUREMENTS [ECM]
Measure the electrical resistance
behaviour of a suspected tooth
spot during controlled drying
procedure.
Measuring Electrode is placed at
the (suspected) spot, while the
patient holds the Reference
Electrode in the hand

21. DETECTION OF CARIES
LASER FLUORESCENCE [LF]
 Diode laser beam of 655 nm
wave length is directed to the
tooth then the reflected
fluorescent light is measured in
a numeric value [0-99 range]
 Two values are displayed
current and peak

22. DETECTION OF CARIES
DIGITAL IMAGING FIBERO-OPTIC
TRANSILLUMINATION [DIFOTI]
High intensity white light is directed
towards teeth through handpiece
and images are captured and stored
in computer system
Demineralized areas of enamel and
dentine scatter light more than
sound areas. Incipient caries appear
as darker areas in the resultant
images.

23. DETECTION OF CARIES
QUANTITATIVE LIGHT-INDUCED FLUORESCENCE
[QLF]
Teeth are illuminated with
high intensity blue light and
images are captured and
stored on the computer
caries lesions are shown
as dark lesion The
software can measure
lesion depth, size and
volume

24. CLASSIFICATION OF CARIOUS
LESIONS BY SITE AND SIZE
[GRAHAM J. MOUNT-2000]
Site 1 - the pits and fissures
Site 2 - the contact areas
Site 3 - the cervical areas

25. CLASSIFICATION OF CARIOUS
LESIONS BY SITE AND SIZE
Size 0 : The initial lesion at any Site that
can be identified but has not yet resulted
in surface cavitation – it may be possible
to heal it
Size 1: The smallest minimal lesion
requiring operative intervention.
The cavity is just beyond healing through
remineralization.

26. CLASSIFICATION OF CARIOUS
LESIONS BY SITE AND SIZE
Size 2 : A moderate sized cavity. There
is still sufficient sound tooth structure to
maintain the integrity of the remaining
crown and accept the occlusal load.

27. CLASSIFICATION OF CARIOUS
LESIONS BY SITE AND SIZE
Size 3 : The cavity needs to be modified
and enlarged to provide some protection
for the remaining crown from the occlusal
load.
There is already a split at the base of a
cusp or, if not protected, a split is likely to
develop

28. CLASSIFICATION OF CARIOUS
LESIONS BY SITE AND SIZE
Size 4 : The cavity is extensive following
loss of a cusp from a posterior tooth or an
incisal edge from an anterior.

29. CLASSIFICATION OF CARIOUS
LESIONS BY SITE AND SIZE
4
Extensive
cavity
3
Enlarged
cavity
2
Moderate
cavity
1
Minimal
cavity
0
No cavity
Size
Site
1.41.31.21.11.01
pit & fissure
2.42.32.22.12.02
Contact area
3.43.33.23.13.03
cervical

30. TREATMENT STRATEGY
Summitt 1996
Enamel caries can generally be managed
without operative intervention
The minimum stage at which surgical
intervention is indicated is carious dentin

31. TREATMENT STRATEGY
Ewoldsen, 2003;
Once the decision has been made to
surgically treat an initial lesion, minimally
invasive techniques should be used
Conservative instrumentation of caries,
adhesive restorations and remineralization
are the core concepts of an emerging
restorative attitude stressing minimally
invasive dentistry

32. Difference between conventional
and minimally invasive cavity
preparation
Conventional:
Extension of cavity for retention and
prevention
Minimally invasive:
Prevention of extension

33. TREATMENT OF EARLY LESION
SIZE 0 [NO CAVITY]
1- Remineralization
 Fluoride therapy
 Casein phosphopeptide-amorphous calcium
phosphate (CPP-ACP)
 Ozone therapy
2- Fissure sealing

34. OZONE THERAPY
What is ozone?
• Energized form of Oxygen (O3)
• Ozone gas is naturally formed in the
atmosphere
• Ozone gas may also be produced by
commercially available ozone
generators

35. OZONE THERAPY
Introduced in dentistry by Dr. Edward Lynch
2002
Ozone eliminates caries flora, acid production
stops, PH rises, demineralization stops and
remineralization starts
12-months data on 1918 lesions showed clinical
reversal of 99% of the lesions. [Holmes 2003]

36. STEPS OF OZONE THERAPY
1- Cleaning
to remove plaque and
organic debris

37. STEPS OF OZONE THERAPY
2- Measurement
to determine degree of
demineralization and
accordingly time of
treatment

38. STEPS OF OZONE THERAPY
3- Treatment
application of ozone for
10 – 40 sec. using
disposable silicone cup
of suitable size for
proper seal

39. STEPS OF OZONE THERAPY
4- Reductant fluid
neutralizes the residual acids
and supplies minerals and
fluorides. Promotes the
immediate remineralization of
the tooth and also eliminates
any ozone residues present.

40. Casein phosphopeptide-amorphous calcium
phosphate (CPP-ACP)
These casein phosphopeptides stabilize calcium
phosphate in nano-complexes in solution as amorphous
calcium phosphate.
The casein phosphopeptides-amorphous calcium
phosphate nano-complexes (CPP-ACP) have been
shown to localize at the tooth surface and prevent
demineralisation.
They also react with fluoride ions to produce an
amorphous calcium fluoride phosphate which will provide
soluble calcium, phosphate and fluoride ions at the tooth
surface and these will allow remineralisation at depth
within the early caries lesion.

41. TREATMENT OF EARLY LESION
Occlusal fissures- size 0
FISSURE SEALING
Mertz-Fairhurtz [1998] found that the progress of the
caries will be arrested as long as the seal remains.
[10 yrs follow up]

42. TREATMENT OF EARLY LESION
Occlusal fissures- size 0
A high strength auto cure GIC
was syringed along the fissures
and positively placed using
finger pressure.
MOUNT 2000

43. TREATMENT OF EARLY LESION
Occlusal fissures- sizes 1and 2
Open only that sections of the fissure
under which the dentin is involved and
remove the infected surface dentine. The
cavity can then be restored and, at the
same time, the remaining fissure can be
sealed.
MOUNT 2000

44. TREATMENT OF EARLY LESION
Occlusal fissures- sizes 1and 2
Surgical intervention can be
undertaken with either;
• Traditional bur [ diamond with a
very fine tapered point]
• Fissurotomy bur
• Air abrasion

45. TREATMENT OF EARLY LESION
Occlusal fissures- sizes 1and 2
Restoration of the cavity with;
• Glass ionomer
• Composite
• Combination
Ngo [1998] {Glass ionomer has the ability
to assist in remineralization of any
remaining demineralized [affected] dentin}.
Lamination with resin composite if occlusal
load is heavy

46. TREATMENT OF EARLY LESION
Occlusal fissures- size 1
Fissure was prepared with
fine tapered diamond bur and
conditioned for 10 sec.
Auto-cured glass ionomer
has been syringed into the
fissure and placed with
positive finger pressure
MOUNT-2000

47. TREATMENT OF EARLY LESION
Occlusal fissures- size 1
Same restoration
after one year
and after eight years

48. TREATMENT OF EARLY LESION
Occlusal fissures- size 2
• Following the original opening there
proved to be an extensive lesion under
the lingual fissure so the cavity outline
was modified and extended in the
region of the lesion only.
• The remaining fissures were explored
conservatively to make sure there was
no other large extension.
• Fissures on the second molar were
similarly explored but that proved to be
a #1.1 lesion only.
MOUNT 2000

49. TREATMENT OF EARLY LESION
Occlusal fissures- size 2
• The walls of the extensive
lesion were cleaned but the
floor was left with softened
demineralized dentine to avoid
a possible pulp exposure.
• Both the cavities are now
being conditioned with 10%
PAA for 10 seconds only.

50. TREATMENT OF EARLY LESION
Occlusal fissures- size 2
• The entire cavities in both teeth
were restored with auto cure
glass-ionomer, immediately
sealed and allowed to mature.

51. TREATMENT OF EARLY LESION
Occlusal fissures- size 2
It was decided that the
occlusal load was too great for
GIC so subsequently it was
laminated for strength. The
glass-ionomer was cut back to
a depth of about 2mm., the
GIC and the surrounding tooth
structure was etched, washed
and dried. Note that the
fissures remain sealed with
glass-ionomer alone.

52. TREATMENT OF EARLY LESION
Occlusal fissures- size 2
The cavity was now restored
incrementally with composite
resin. Note that the second
molar was restored with the
glass-ionomer alone.

53. Sealant Restorations
Sealant alone
Composite + sealant
Glass ionomer + sealant
Glass ionomer + composite + sealant
Hassall and Mellor 2001

54. Sealant Alone
Decalcified fissure. No radiographic sign of
dentine involvement.
Less than two other carious lesions in
mouth.

55. Composite plus Sealant
Decalcified fissure. Enamel cavity with no
dentine involvement
More than two other carious lesions in
mouth.

56. Glass ionomer cement
plus Sealant
Cavity in dentine with minimal lateral
spread.
Margins not in colossal contact.

57. Laminate Restoration
Lesion in dentine with lateral spread along
EDJ.
Cavity margins in occlusal contact.

58. TREATMENT OF EARLY LESION
proximal lesions size 0
Two option are available
1- To promote remineralization.
2- To prepare tunnel cavity and the enamel
of the proximal surface can be left intact
on assumption that it will remineralize.
MOUNT 2000

59. TREATMENT OF EARLY LESION
proximal lesions size 1
Treatment for these lesions will be dependant
upon its position in relation to the crest of the
marginal ridge and ease of access. There are
three variations;
• Tunnel cavity
• Slot cavity [occlusal]
• Proximal approach
A fourth technique was described by Nels
Ewoldsen, 2003;
• Facial slot

60. TREATMENT OF EARLY LESION
proximal lesions size 1
TUNNEL CAVITY
[occlusal fossa or tunnel approach]
The lesion is >2.5 mm below the marginal
ridge so it is possible to retain the basic
strength of the proximal surface of the
crown of the tooth.

61. TREATMENT OF EARLY LESION
proximal lesions size 1
TUNNEL CAVITY
The cavity is opened through a
limited access from the occlusal
fossa just medial to the marginal
ridge with a small cylindrical
diamond bur until the lesion is
identified. The access cavity is
then carefully enlarged to a
triangular form, particularly
buccally and lingually, to improve
visibility.

62. TREATMENT OF EARLY LESION
proximal lesions size 1
• A short strip of a metal matrix band should
be placed interproximally and wedged in
place, to protect the adjacent tooth and to
serve as matrix during restoration.
• The area of enamel breakdown can now
be carefully debrided until demineralized
but firm enamel is left surrounding the
cavitation.

63. TREATMENT OF EARLY LESION
proximal lesions size 1
At this point, any infected surface dentin
will have been removed, and the
remaining affected dentin on the axial wall
can be left in place in the expectation that
it will be remineralized in the presence of a
biologically active restorative material.
There is no need to place a sublining,
such as calcium hydroxide, on the axial
wall. In fact this would more likely interfere
with the desired ion exchange adhesion.

64. TREATMENT OF EARLY LESION
proximal lesions size 1
• The material of choice for
restoration of such a limited cavity
is glass ionomer cement. It can be
light activated or autocured.
• If the occlusion is too heavy, 2mm
of glass ionomer can be removed
from the surface, after it has set,
and a resin composite can be
bonded to both the enamel and the
cement.

65. TREATMENT OF EARLY LESION
proximal lesions size 1
SLOT CAVITY
The lesion is <2.5mm below the crest of
the marginal ridge which is likely to fail if a
tunnel is prepared.

66. TREATMENT OF EARLY LESION
proximal lesions size 1
slot cavity
Enter the lesion through the outer slope of
the marginal ridge thus forming a small
slot or box-like cavity.
A short metal strip should be placed and
wedged.
Only completely degraded enamel need to
be removed
Demineralized affected dentin on the axial
wall can be left in place.

67. TREATMENT OF EARLY LESION
proximal lesions size 1
slot cavity
The marginal ridge is retained as much as
possible and opened laterally, only enough to
identify the extent of the lesion.
The occlusal fissure is not included unless it is
frankly carious.
The fissure can, however, be sealed with the
final restoration.
A contact with the adjacent tooth to the buccal or
lingual of the slot is retained wherever possible.

68. TREATMENT OF EARLY LESION
proximal lesions size 1
slot cavity
Depending upon the occlusion it is
possible to restore this cavity with
glass-ionomer only or else it can
be based with GIC and laminated
with composite resin.

69. TREATMENT OF EARLY LESION
proximal lesions size 1
Proximal approach
Possible when a larger lesion in the
adjacent tooth is being restored.
A very conservative design can be
undertaken. The marginal ridge can
be maintained, and only those
areas of enamel that are completely
degraded should be removed.
The infected dentin can be debrided
with a small, round bur.
Cavity is restored with GIC

70. TREATMENT OF EARLY LESION
proximal lesions size 1
FACIAL SLOT
Roggenkamp first described the facial slot
class 11 cavity for use with amalgam in
1982, then it was modified by Croll in 1995
for use with GIC [resin-modified and silver-
cement GI]. Ewoldsen in 2003 described a
a technique for use with highly viscous,
rapid setting, capsulated GIC

71. TREATMENT OF EARLY LESION
proximal lesions size 1
FACIAL SLOT
Indication:
Early class 11 lesion with surface cavitation and
2mm of intact enamel exists beneath the intact
marginal ridge.
Instrumentation:
• Using a slow-speed handpiece and the
smallest round bur available, access the lesion
in the most direct manner possible
• Use tactile skills to follow dento-enamel
junction occlusally, gingivally and lingually.

72. TREATMENT OF EARLY LESION
proximal lesions size 1
FACIAL SLOT
• If caries remain pulpally switch to a
no. 329 bur and remove softened
dentin until sufficient space exists to
insert a small spoon excavator, then
excavate the lesion until the spoon
rings against affected dentin. At this
point all infected dentin will have
been removed.
• Use the spoon to excavate around
the cavosurface margin to ensure
extension into sound enamel

73. TREATMENT OF EARLY LESION
proximal lesions size 1
FACIAL SLOT
Restoration:
• Position but do not tighten a
toffelmire-type matrix system
• Conditioner may be applied
before or after placement of
matrix for 15 sec.
• Blot away excess moisture with
a cotton pellet

74. TREATMENT OF EARLY LESION
proximal lesions size 1
FACIAL SLOT
• With the matrix band still loose
place the cement capsule nozzle
as close to the access site as
possible
• Deliver cement until overflow is
evident then immediately tighten
the matrix band and allow it to
remain in place for 3 minutes
• Remove the matrix, eliminate the
excess material and apply a
protective coating

75. TREATMENT OF EARLY LESION
proximal lesions size 1
FACIAL SLOT
Facial slot restoration after 2 years

76. Thank you
Discussion