This document provides an overview of minimally invasive dentistry (MID), including: 1. MID aims to conserve healthy tooth structure using prevention, remineralization, and minimal intervention. It focuses on performing only necessary dentistry using long-lasting materials. 2. Key principles of MID include disease control, remineralization of early lesions, avoiding removal of excess tooth structure, and using strong, long-lasting materials. 3. Techniques discussed include caries diagnosis/risk assessment, various caries removal methods like air abrasion and lasers, fissure sealants, preventive resin restorations, ART, and chemo-mechanical caries removal.

1. 1

2. Dr. Nabeela Basha
Seminar - 15

3. Contents:
• Introduction
• History
• Principles
• The Minimal intervention approach
• Caries removal & restoration
• Recent advances in caries removal techniques
• Cavity designs for Minimal intervention
• Restorative materials used in MID
• Dental Public Health Significance
• Conclusion
• Previous year questions
• References
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4. 4

5. What is minimally invasive dentistry and
how is it different from regular dentistry?
• The goal of minimally invasive dentistry, or microdentistry, is to
conserve healthy tooth structure. It focuses on prevention,
remineralization, and minimal dentist intervention.
• Using scientific advances, minimally invasive dentistry allows
dentists to perform the least amount of dentistry needed while
never removing more of the tooth structure than is required to
restore teeth to their normal condition.
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6. • In addition, in minimally invasive dentistry, dentists use long-
lasting dental materials that conserve the maximum tooth
structure so the need for future repairs is reduced.
http://www.agd.org/public/OralHealthFacts/files/pdfgenerator.a
spx?pdf=FS_MinimallyInvasiveDentistry.
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7. Definition
• Minimum Invasion Dentistry (MID) is defined as a philosophy of
professional care, concerned with the occurrence, early detection
and earliest possible cure of disease on a micro level, followed by
minimally invasive treatment in order to repair irreversible
damages caused by such disease.
Tyas MJ, Anusavice KJ, Frencken JE, Mount GJ. Minimal
intervention dentistry-a review. FDI Commission Project 1-97. Int
Dent J. 2000;50:1–12.
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8. Golden Triangle of MID
• A thorough understanding and
appreciation of the interplay between
three critical factors is required to
achieve success clinically when
using a minimally invasive
operative caries management
strategy.
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9. Timeline of MID developments
1836-1915
• GV Black = all softened or discoloured tooth structure was
removed and all the walls had to extend out to ‘caries free’
areas.
• GV Black identified the fact that the presence of bacteria was a
necessary factor in caries and suggested that the profession
had an obligation to continue to research on
this problem.
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10. • In 1895, Wilson reported the placement of dental cement in
pits and fissures to prevent caries.
• In 1923, Hyatt advocated early insertion of small restorations
in deep pits and fissures before carious lesions had the
opportunity to develop. He termed this procedure
‘prophylactic odontotomy’. Disadvantage is that it requires the
cutting of tooth structure.
• In 1929, Bodecker suggested that deep fissures could be
broadened with a large round bur to make the occlusal areas
more self-cleansing, a procedure that is called enameloplasty.
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11. • 1940s- Restorative materials: silicate cement with fluoride
releasing ions
• Acid etch technique, introduced first by Buonocore in 1955,
started a new era in preventive dentistry. Etching the enamel
and bonding of the sealant material by a resin marked an
approach towards a more preventive mode in the caries
treatment.
• 1956 - Miller suggested copper cements, suppressing bacterial
activity
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12. • 1970- Graham Mount proposed MID technique.
• 1974- Dan Erikson presented the MID technique to the world.
• 1976- Glass ionomer cements were developed.
• 1978- Simonsen and Stallard, were the first to describe
preventive resin restorations and to report the results of a
clinical trial.
• ART was pioneered in Tanzania in the mid-1980s as part of a
community-based primary oral health program by the
University of Dar-us-Salaam.
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13. • 1980-84- Jo E Frencken used ART technique using
polycarboxylates.
• 1988-90- Revolutionary period- adhesives were used in ART.
• 1994- World Health Day - ART was proposed and accepted at
WHO.
• 1998- ART use started in clinics.
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14. PRINCIPLES
 Disease control by reduction in cariogenic bacteria.
 Remineralization of early lesions.
 Avoid removal any more tooth structure than is absolutely
required to restore teeth to their normal conditions.
 Use of dental materials that conserve the maximum of tooth
structure.
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15.  Use of only the strongest and longest lasting dental materials
to reduce, the need for future repairs and replacement.
 Repair, rather than replacing defective restorations.
 Use of dental procedures that keep the number of necessary
appointments to the minimum.
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16. The Minimal Intervention Approach
• Cariology has advanced over the past 30 years with scientific
advances in the knowledge of the caries process in terms of its
pathogenesis, its transmission, the demineralization and
remineralization continuum, the mode of action of fluoride, but
also with respect to the great technological developments in
biomaterials, equipment for the detection of caries lesions and
methods for cavity preparation.
• The MI approach includes:
Early detection of caries
Caries removal and restoration
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17. Caries diagnosis
• The fundamental purpose of using caries diagnostic methods is
to be able to identify, detect and classify the lesions to select
most appropriate intervention for the patient.
• It includes:
A. CARIES RISK ASSESSMENT
B. EARLY DETECTION OF CARIES
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18. CARIES RISK ASSESSMENT
• Risk is defined as “the probability of an individual developing
a given disease” and thus a risk factor is a factor associated
with an increased probability of an individual developing a
particular disease.
• Caries risk assessment is the determination of the probability
of person’s developing new caries lesions during specific
period and the probability of a change in the size or activity of
existing lesions over time.
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19. • Since caries is preventable, the diagnosis of caries as a lesion in
a tooth is not sufficient for a treatment plan. For this, a proper
‘medical’ diagnosis is required based on certain components.
• Firstly, caries must be recorded on each surface as either initial
lesions (reversible) or cavities (irreversible).
• Secondly, it should be assessed to estimate the severity of
caries.
• Thirdly it assesses the future caries activity.
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20. Factors Relevant to Caries Risk Assessment
20

21. EARLY DETECTION OF CARIES
• Visual and tactile examination and dental radiographs are
commonly used methods for caries detection.
• In recent years, newer caries detection methods and devices
have been developed, as traditional caries detection procedures
do not detect caries until they have progressed through at least
the thickness of enamel. These include:
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22. 1. Laser fluorescence
2. Fiber-optic transillumination
3. Digital imaging fiber-optic transillumination
4. Ultraviolet illumination
5. Electronic caries detector
6. Dye penetration method
7. Quantitative light-induced fluorescence (QLF)
8. Ultrasound imaging
9. Endoscope / Videoscope
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23. CARIES REMOVALAND
RESTORATION
• Rotary instruments used for the treatment of carious lesions
have often resulted in a considerable removal of tooth
structure.
• Newer techniques for removal of carious dentin have been
developed to minimize this excessive tissue loss.
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24. PIT AND FISSURE SEALANTS
• The changes in caries epidemiology in the beginning of the
1990’s and the reporting of slower progression of caries
lesions, led to suggestions that sealant use should be targeted
to those teeth most prone to develop caries lesions.
• The development of sealants has progressed from the first
generation sealants which were activated with ultraviolet light,
through the second and third generations of autopolymerised
and visible-light activated sealants, to the fourth generation
containing fluoride. First generation sealants are no longer
marketed.
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25. Indications:
• Deep, narrow pits and fissures.
• Recently erupted teeth.
• Where there are no caries in the proximal surfaces.
• Patient with high caries risk though this increases the tendency
and need for reapplication.
Contraindications:
• Teeth with occluso-proximal lesions.
• Teeth with proximal lesions.
• Teeth that is caries free for 4years or more.
• Teeth with broad well coalesced pits and fissure.
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26. Retention rate of PFS
• Meta-analyses have shown that auto-polymerizing sealants were
found to have a five-year retention rate of 64.7%.
• Resin-based light-polymerizing sealants and fluoride-releasing
products showed five-year retention rates of 83.8% and 69.9%
respectively.
• However, poor retention rates of <19.3% were documented for
UV-light-polymerizing materials, compomers and GIC based
sealants.
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27. Preventive Resin Restoration (PRR)
• PRR is indicated in teeth with minimal teeth and fissures
decay.
• In this minimal cavity preparation is required to prevent
unnecessary removal of healthy tooth structures for retention.
• If the decay is limited to enamel then no local analgesia is
required. After etching, rinsing and drying the cavity is
condensed with a normal composite or GIC.
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28. • TYPES OF PRR Based on the extent and depth of the carious
lesions:
 Type A - Suspicious pits and fissures where caries removal is
limited to enamel.
 Type B - Incipient lesion in dentin that is small and confined.
 Type C - Characterized by the need for greater exploratory
preparation in dentin.
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29. Survival of PRRs
29

30. ART (Atraumatic Restorative
Technique)
• The Atraumatic restorative treatment is a procedure based on
removing carious tooth tissues using hand instruments alone
and restoring the cavity with an adhesive restorative material.
• Goals of ART are:
 Preserving the tooth structure
 Reducing infection
 Avoiding discomfort
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31. Procedure for ART:
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32. 32

33. Advantages of ART
 Easily available inexpensive hand instruments are used rather
than the expensive electrically driven dental equipment.
 As it is almost a painless procedure the need for local
anesthesia is eliminated or minimized.
 ART involves the removal of only decalcified tooth tissues,
which results in relatively small cavities and conserves sound
tooth tissues as much as possible.
 Sound tooth tissue need not be cut for retention of filling
material.
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34.  The leaching of fluoride from glass ionomer probably
remineralizes sterile demineralized dentin and prevents
development of secondary caries.
 The combined preventive and curative treatment can be done
in one appointment.
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35. Disadvantages of ART
• ART restorations are not long lasting. The average life is two
years depending upon the rate of caries activity of the
individual oral cavity.
• Because of the low wear resistance and low strength of the
existing glass ionomer materials their use is limited.
• The continuous use of hand instruments over long period of
time may result in hand fatigue.
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36. Survival of ART restorations
36

37. AIR ABRASION
• The instrument was first developed in the 1940’s by Dr. Robert
Black.
• It is a method of tooth structure removal that is considered to
be an effective alternative to the standard dental drill.
• It removes tooth structure using a stream of aluminium oxide
particles generated from compressed air or bottled carbon
dioxide or nitrogen gas.
• The abrasive particles strike the tooth with high
velocity and remove a small amount of tooth
structure.
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39. 39

40. Advantages
 It is painless.
 Local anesthesia is rarely needed.
 It works quickly.
 There is no vibration or pressure to cause microfractures that
weaken tooth.
 There is no production of heat to damage the dental pulp and
lesser sound tooth structure is removed.
40

41. Disadvantages
• Depth of preparation cannot be controlled easily.
• Must be used in caution when used adjacent to soft tissues as it
may lead to surface injuries.
• The preparation does not render a well-finished surface.
• Air abrasion can cause subcutaneous emphysema.
41

42. LASERS
(light amplification by stimulated emission of radiation)
• In 1997, the Food and Drug Administration approved the use
of Erbium: Yttrium Aluminium Garnet laser for caries removal
in the USA.
• It operates at a wavelength of 2.94 μm and is used for the
caries removal, cavity preparation in both enamel and dentine
and for the preparation of root canals.
• Laser treatment is appreciated by patients as they are more
comfortable than drilling.
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43. • CO2-laser = Caries inhibition up to 82.7%
• Er: YAG- laser = Reduction in surface lesion depth (root
surfaces 39%, enamel surfaces 56%)
• Nd: YAG-laser (with Duraphat) = Caries inhibition (pits and
fissures 43%, smooth surfaces 80%).
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44. MICRO-PREPARATION AND FISSUROTOMY
BURS
• Many manufacturers are now producing smaller burs for
cavity preparation using MI techniques. The burs are spherical,
tapered or elliptical. Examples include fissurotomy burs (SS
White, USA) and narrow diamond burs (Brassler, USA).
• The instruments are manufactured using a special high-tensile
steel to produce a thin neck.
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45. • Used with the aid of magnification, these allow very precise
preparation of teeth. Micro-preparation burs allow the dentist
to conservatively explore and modify the fissures even when
caries has spread laterally along the dentino-enamel junction.
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46. CARIES DETECTOR DYES
• In caries removal during cavity preparation, only the soft,
heavily infected outer dentin must be removed, whereas the
demineralized, uninfected inner dentin should be left.
• Caries-detecting dyes (e.g.1.0% acid red in propylene glycol)
have been developed in distinguishing between the two types
of caries.
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47. OZONE APPLICATION
• Ozone is part of a natural gas mix that surrounds the earth at
high altitude and protects world’s population from excessive
UV radiations.
• The O3 technology was developed by Prof. Dr. Edward Lynch.
• This technique utilizes O3 gas which is applied to the tooth
surface in a controlled manner with the use of heal ozone
delivery handpiece.
• This O3 gas eliminates decay causing bacteria. Once the
bacteria are eliminated the treated surface can be restored or
left to re-mineralize.
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48. Chemo-mechanical Caries Removal
• An alternative to the conventional mechanical removal of
caries.
• The idea of chemo-mechanical caries removal (CMCR) was
developed in 1970s by Goldman.
• The need for local anesthesia is reduced or eliminated as there
is little pain during the procedure.
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49. • It is an effective alternative for caries removal because it
brings together atraumatic characteristics and bactericide /
bacteriostatic action.
• The chemicals used can be in the form of liquid (caridex) or
gel (carisolv).
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50. Caridex
• It was developed by CM Habib from a formula made of N-
mono -chloroglycine and amino butyric acid and was called as
GK 101 E.
• It gained FDA approval in 1984.
• It was initially introduced on the US market in 1985.
• The system involved the intermittent application of preheated
N-monochloro-DL-2-aminobutyric acid (GK-101E) to the
carious lesion.
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51. • The solution was claimed to cause disruption of collagen in the
carious dentine, thus facilitating its removal.
• Disadvantages-
1. Expensive
2. Large quantity required
3. Solution has to be heated
4. Short shelf-life
51

52. Carisolv
• Carisolv (MediTeam Dental, Göteborgsvägen, Sweden) is a
chemo-mechanical method of removing dental caries that is
minimally invasive.
• It constitutes amino acids and 0.5% sodium hypochlorite and
is applied to the dentin.
52

53. • The new system is marketed in two syringes:
Red Gel: Glutamic acid, leucine, lysine, sodium chloride,
erthrosine , water and sodium hydroxide.
Transparent Gel: 0.5% Sodium hypochlorite
• The average time required for complete caries removal is
about 9-12 minutes and the volume of gel utilized for this
purpose is only 0.2-1.0 ml.
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54. Procedure
• The 2 gels are mixed in equal amounts at room temperature.
• The mixture is applied using hand instruments onto the
decayed dentin.
• Wait for 30 seconds to allow dissolution of carious dentin.
• Special instruments are then used to remove softened caries.
• The instruments designed to scrape in two or in several
directions, reduce the friction during caries removal.
• When caries is excavated, remove all the gel, wipe with a
cotton pellet and rinse with lukewarm water. Check with an
explorer to ensure that no more soft dentin is remaining. 54

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56. Advantages:
• Very effective method of caries removal.
• Unlike the caridex system, carisolv dissolves only the carious
dentin and keeps the healthy dentin intact.
Disadvantages:
Despite its effectiveness, carisolv was not a blockbuster mainly
because it required-
• Extensive training of professionals.
• Customized instruments which are costly.
56

57. Papain Gel
• To overcome the disadvantages of carisolv system, in 2003, a
research project in Brazil led to the development of a new
formula to universalize the use of chemo-mechanical method
for caries removal and promote its use in public health.
57

58. • The new formula was commercially known as Papacarie.
• It is available in syringe form which contains blue-colored gel.
58

59. • It is basically composed of Papain, chloramines, toluidine
blue, salts, thickening vehicle, which together are responsible
for the papacarie’s bactericidal, bacteriostatic and anti-
inflammatory characteristics.
• Papain comes from the latex of the leaves and fruits of the
green adult papaya.
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60. • Papain promotes:
 Chemical debridement
 Granulation and epithelialization, which hastens the phases of
cicatrization
 Stimulation of the tensile strength of the scars.
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61. Procedure
1. Apply Papacarie in the carious dentin.
2. Wait for the gel to act for 40-60 seconds.
3. Scrape the softened dentin using old/blunt curettes as
specified by the manufacturer.
4. The gel can be reapplied as many times till the colour of the
gel remains unchanged.
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62. RESTORATIVE MATERIALS USED IN
MID
• Newer generation of materials known as SMART materials are
used in MI procedure.
• The new composite resins are showing great success because
they visually reflect, refract, & absorb light in similar manner
as natural dentition.
• When esthetic materials (eg, composite resin, RMGIC, etc) are
able to mimic the physical properties of the human dentition,
biomimetic results can ultimately be attained
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63. • It implies that the material will be biocompatible, that is-
biologically acceptable to and not rejected by adjacent vital
tissues.
• It has also been shown recently that it is safe to leave the
softened, demineralized, affected, but sterile, dentin on the
floor of the cavity. If the cavity is then sealed with a
biomimetic restoration that releases calcium, phosphate, and
fluoride ions the result will be remineralization and healing of
the underlying dentin.
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65. 65

66. CAVITY DESIGNS FOR MINIMAL
INTERVENTION
• Tunnel Preparation
• Slot Cavity Preparation
• “Minibox” Approximal Cavity Preparations
• “Full Box” Approximal Cavity Preparation
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67. Tunnel Preparation
• It could be used when the lesion is more than 2.5 mm below
the crest of the marginal ridge and the contact area may remain
sound and the marginal ridge may be quite strong. (Wilson and
Mc Lean, 1988).
• Access to the lesion through the occlusal surfaces should be
limited to the extent required to achieve visibility and should
be undertaken from an area that is not under direct occlusal
load (Knight, 1984).
67

68. • Access may be gained through the occlusal surface with No. 2
bur about 2.0 mm from the marginal ridge.
• Resin-modified glass ionomer cement is the current material of
choice for this restoration. They are radiopaque and have been
shown to prevent microleakage.
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69. 69

70. “SLOT CAVITY PREPARATIONS”
• It could be used when the lesion is less than 2.5 mm below the
crest of the marginal ridge.
• The basic principles of cavity design remain the same, with the
objective of removing only that tooth structure that has broken
beyond the possibility of remineralization.
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71. “Minibox” Approximal Cavity
Preparations
• In this preparation, the excavation of the dentin lesion is same
as for the previous preparations.
• The design differs only in the handling of the enamel.
• Initially, the integrity of enamel wall needs to be preserved by
extending the margins where it can be considered stable and
durable.
• A full box need not to be developed.
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72. • It is preferable to retain and reinforce this enamel even if it is
unsupported by dentin by placing glass ionomer cement base.
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73. “Full Box” Approximal Cavity
Preparation
• It is a very common procedure, where the enamel is in
hopelessly poor condition and needs refining after eradicating
the dentin lesion.
• The final refinement will depend on the type of restoration to
be placed.
• For example, the preparation design for an amalgam or
composite restoration differs from the design for a porcelain or
gold inlay
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75. Dental Public Health Significance of
MID
 Implementation of the MID approach in community dental
clinics would enable the management of dental caries as a
disease process through identification of its aetiologies and
addressing these through clinical and health promotion
mechanisms.
 A change in culture, through education and practice, is required
to instill the paradigm shift from surgical management of the
disease to one of prevention
75

76.  Extensive demand for emergency services and long wait lists for
adults in the public sector make it difficult to see adult patients
regularly to enable early identification of oral disease and
implementation of early intervention protocols to prevent
progression to irreversible oral disease.
 There is also a requirement for education and information to
assist patients in understanding the implications of the MID
approach to treatment
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77.  There is also a major need to analyze the cost-benefit ratio of MI
techniques, so that the effectiveness can be more convincingly
demonstrated to the many providers.
 In order to implement an MID approach there needs to be
significant investment and resourcing by government.
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78. CONCLUSION
⸙ It is time for changes in the principles of operative dentistry. The
disease should be treated first; the surgical approach should be
undertaken only as a last resort and efforts should be made to
preserve a maximum amount of sound tooth structure.
⸙ Although further research is needed, it can so far be concluded
that minimum intervention has the potential to apply a more
conservative approach to caries treatment and health orientated
treatment option.
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79. PREVIOUS YEAR QUESTIONS
• Principles of MID. [7 marks, RGUHS Oct 2010]
• Minimal invasive dentistry. [7 marks, RGUHS July 2017]
• Chemo-mechanical methods of caries removal. [7 marks,
RGUHS Nov 2017]
• Minimal Invasive treatment [10 marks Sumandeep Vidyapeeth
Dec 2009]
79

80. REFERENCES
• Hiremath SS. Textbook of Public Health Dentistry. 3rd edition.
Elsevier Publishers, New Delhi; 2016.
• Mickenautsch S. An introduction to minimum intervention
dentistry. Singapore Dent J.2005 Dec;27(1)1-6.
• Deise Cruz Oliveira. Minimally invasive dentistry approach in
dental public health. University of Iowa Iowa Research Online
2011
• Carol A, Mary E. Minimally Invasive Dentistry. JADA, January
2003 ;134:87-95.
80

81. • Banerjee A. Minimal intervention dentistry: part 7. Minimally
invasive operative caries management: rationale and techniques.
British Dental Journal 2013; 214(3): 107-111.
• Tyas MJ, Anusavice KJ, Frencken JE, Mount GJ. Minimal
intervention dentistry — a review FDI Commission Project 1–97.
International Dental Journal February 2000; 50(1):1-12.
• Mount GJ. Minimal intervention dentistry: Cavity classification
and preparation. J Minim Interv Dent 2009;2(3).
• Alonso et al. Minimal Invasive Dentistry: Bond Strength of
different sealant and filling material to enamel. Oral Health Prev
Dent 2005;3(2):87-95.
81

82. • Anuradha P, Yadav R. Minimal Invasive Dentistry: Benefits and
Challenges. Arch of Dent and Med Res 2016;2(2):25-26.
• Garg et al. Minimal Invasive Dentistry- A Comprehensive
Review; BJMMR 2016, 17(5): 1-9; Article no.BJMMR.27526.
• Gujjar KR & Sumra N. Minimally Invasive Dentistry - A Review.
International Journal of Clinical Preventive Dentistry, Vol. 9, No.
2, June 2013: 109-120.
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