The document provides information on trauma from occlusion and coronoplasty. It defines trauma from occlusion as damage to the periodontium caused by excessive occlusal forces. Coronoplasty involves selective reduction of occlusal surfaces to influence mechanical contact conditions and sensory input, with the aim of reducing excessive tooth mobility and providing functional stimulation for periodontal health. The document discusses the diagnosis, classification, and clinical features of trauma from occlusion, as well as the objectives, methods, and techniques used in performing coronoplasty.

1. Good
morning

2. Presented by :
Shashwati Paul
II Yr PG Student
Dept. of Periodontology

3. 
Contents
 Introduction
 Trauma from occlusion
 Definition
 Classification
 Diagnosis of trauma from occlusion
 Dynamics of Equilibrium
 Coronoplasty
 Guidelines for occlusion in dental treatment
 Indications for coronoplasty in periodontal therapy
 Objectives of coronoplasty
 Occlusal adjustments
 Technique of coronoplasty
 Outcome of coronoplasty
 Treatment of increased tooth mobility
 Conclusion
 References

4. 
INTRODUCTION
 Occlusal force affect the condition and structure of the
periodontium. Periodontal health is not a static state.
 It depends upon a balance between an internal systemically
controlled milieu that governs periodontal metabolism and
external environment of the tooth, of which occlusion is an
important component.
 To remain structurally and metabolically sound, the
periodontal ligament and alveolar bone require the
mechanical stimulation of occlusal force

5. 
 An inherent “margin of safety” common to all tissue
permits some variation in occlusion without the
periodontium being adversely affected.
 The periodontium has a capacity to withstand slight
variations of masticatory forces.

6. 
 The ability of periodontium to accommodate some amount
of extra force is called the physiological adaptive capacity.
 If the force exceed the physiological adaptive capacity, injury
to the periodontal tissue results.
 Periodontal injury thus caused is known as “trauma from
occlusion”

7. 
DEFINITIONS
 Trauma from occlusion was defined by Stillman ( 1917) as "a
condition where injury results to the supporting structures
of the teeth by the act of bringing the jaws into a closed
position".
 WHO in 1978 defined trauma from occlusion as "damage in
the periodontium caused by stress on the teeth produced
directly or indirectly by teeth of the opposing jaw".

8. 
 “Glossary of Periodontic Terms" (American Academy of
Periodontology 1992), Occlusal Trauma was defined as "An
injury to the attachment apparatus as a result of excessive
occlusal force”
 Primary occlusal trauma is injury resulting from excessive
occlusal forces applied to a tooth or teeth with normal
support
 Secondary occlusal trauma is injury resulting from normal
occlusal forces applied to a tooth or teeth with inadequate
periodontal support.

9. 
 Combined occlusal trauma refers to injury resulting from
abnormal occlusal forces applied to a tooth or teeth with inadequate
(abnormal) periodontal support. (Bjorndahl O 1958)
 Traumatogenic occlusion refers to a cause and is defined as any
occlusion that produces forces that cause an injury to the
attachment apparatus

10. 
 Trauma from occlusion is only one of many terms that have
been used to describe such alterations in the periodontium.
 Other terms often used are;
 Traumatizing occlusion
 Occlusal trauma
 Traumatic occlusion
 Traumatogenic occlusion
 Periodontal traumatism
 Overload , etc.

11. 
CLASSIFICATION
 DEPENDING UPON THE DURATION OF OCCURANCE
 Acute TFO
 Chronic TFO
 DEPENDING ON THE ETIOLOGY
 Primary TFO
 Secondary TFO

12. Primary TFO Secondary TFO

13.  Three different situations on which excessive occlusal
forces can be superimposed, as follows :
a) Normal periodontium with normal height of bone
b) Normal periodontium with reduced height of bone
c) Marginal periodontitis with reduced height of bone

14. 
CLINICAL FEATURES
SYMPTOMS OF TRAUMA FROM OCCLUSION
1. Periodontal pain
 In severe trauma from occlusion, there is localized, sharp
pain or soreness to the tooth.
 In chronic long standing trauma from occlusion, there is
little or no pain.
 The symptoms, if present are those of vague regional
discomfort

15. 
2. Pulpal pain
 Sensitivity of the teeth, especially to cold, is commonly
found .
3. Food impaction
 The plunger cusp effect of occlusal interference may produce
a functional opening of contact between the teeth, leading to
food impaction.
4. TMJ pain
 This is always accompanied by an occlusal disharmony.

16. 
SIGNS OF TRAUMA FROM OCCLUSION
1. Increased tooth mobility
 This is a hallmark of trauma from occlusion
 It can be easily measured by blunt ends of two dental
instruments which are placed approximately at the buccal
and lingual heights of contour of the tooth, and force are
applied in the bucco-lingual direction.

17. 
MILLER’S MOBILITY INDEX (1950)
 Mobility 1 – First distinguishable sign of movement greater
than normal.
 Mobility 2 – Movement of 1 mm from normal position in
any direction.
 Mobility 3 – Greater than 1 mm and rotation, or depression.

18. 
Fleszar et al (1980) used a modification of Miller’s scale :
 Class 0 – Physiologic mobility
 Class I – Slightly increased mobility
 Class II – Definite to considerable increase in mobility, but no
impairment of function
 Class III – Extreme mobility faciolingually / mesiodistally
combined with vertical displacement

19. 2. Migration of teeth
 Loss of inter proximal contact and migration of teeth may be
seen in traumatic occlusal relation.
3. Atypical pattern of occlusal wear
 Tooth wear which appears to be greater than one might
expect in a patient of that age, and which cannot be
attributed to any special diet or deficiency in tooth
mineralization.

20. 4. Changes in percussion sound
 On percussion, the tooth affected by trauma from occlusion,
gives a dull sound whereas a normal teeth gives a sharp
sound.
 This difference could be due to altered width and
consistency of periodontal membrane, and partial resorption
of lamina dura.
5. Hypertonicity of masticatory muscles
 Bruxism and hypertonicity makes the periodontium
susceptible to trauma.

21. 6. Periodontal abscess
 If the tooth subjected to increased force, have pockets, the
bacteria may get pushed into the traumatized tissue and
cause abscess formation.
7. Fremitus test
8. Radiographic changes
 Widening of periodontal space at crest, giving funnel-shaped
appearance and angular bone loss.

22. 
RADIOGRAPHIC FEATURES OF
TRAUMA FROM OCCLUSION
 Trauma from occlusion produces radiographicaly detectable
changes in the lamina dura, periodontal ligament spaces,
morphology of alveolar crest, and density of surrounding
bone.
 These changes include :
 Increased width of periodontal space, often with thickening of
lamina dura along the lateral aspect of root, in the apical
region and in the bifurcation areas.
 A “vertical” rather than horizontal destruction of interdental
septum.

23.  Widening of periodontal ligament space at the crest, giving a
funnel-shaped appearance and angular defects during
adaptive remodeling stage.
 Root resorption is seen.

24. 
Diagnosis
1.HISTORY
 An adequate history is of basic importance of any clinical
diagnosis.
 H/O parafunctional habits must be recorded.
 Patients psychic status must also be recorded.

25. 
CLINICAL INDICATOR OF OCCLUSAL TRAUMA
• It may include one or more of the following :
1. Fremitus
2. Mobility (progressive)
3. Occlusal discrepancies
4. Wear facets in the presence of other indicators
5. Tooth migration
6. Sensitivity

26. Fremitus test
 Test to detect trauma from occlusion.
 Fremitus is a measurement of the vibratory pattern of the
teeth when the teeth are placed in contacting position and
movements.
 To measure fremitus ,a dampened index finger is placed
along the buccal and labial surface of the maxillary teeth. The
patient is asked to tap the teeth together in the maximum
intercuspal position and then grind systematically in the
lateral, protrusive, and lateral-protrusive contacting
movements and positions.
 The teeth that are displaced by the patient in these jaw
positions are then identified.

27.  The following classification system is used :
Class I fremitus – Mild vibration or movement detected
Class II fremitus – Easily palpable vibration but no visible
movement
Class III fremitus – Movement visible with naked eye
 Fremitus differs from mobility in that fremitus is tooth
displacement created by patient’s own occlusal force.
 Fremitus is a guide to the ability of the patient to displace
and traumatize the teeth.

28. 
 It is the first ever grid-based sensor technology specifically
designed for occlusal analysis.
 This diagnostic tool was created in response to the needs of
dentists seeking an accurate way to dynamically measure
occlusion.
 It offers instantaneous occlusal data, including timing and
force. The 3rd generation system features a consistent
sampling speed of 100 Hz and advanced software analysis
tools to provide better quality treatment.
T-Scan

29. 
 It raises the bar for occlusal analysis by employing
patented grid-based sensor technology.
 The ultra-thin, reusable sensor, shaped to fit the dental
arch, inserts into the sensor handle, which connects into
the USB port of PC.
 The software’s vivid graphics (2-D, 3-D, force vs. time
graph) display tooth contact data instantaneously and
accurately, highlighting each tooth and the force level
exerted on that tooth during occlusion.
 With this data, visualizing and achieving the balance of
the perfect bite is easy to accomplish.

30. 

31. 
Primary requirements for successful occlusal therapy
 Comfortable and stable tmjs
 Anterior teeth in harmony with the envelope of
function
 Non-interfering posterior teeth
Even the slightest disharmony causes severe
hyperactivity and incoordination of masticatory muscle
function. So it is the fourth factor that is affected
positively or negatively by how the other three factors
work together.
Dynamics of Equilibrium

32. 

33. 
Coronoplasty
 Coronoplasty is the selective reduction of occlusal areas with the
primary purpose of influencing the mechanical contact conditions
and the neural pattern of sensory input ( Krough – Poulsen 1968)
 It is a direct and irreversible change of the occlusal scheme.
 There is a tendency to think of occlusal adjustment solely as
eliminating injurious occlusal forces.
 But an equally important purpose is to provide the functional
stimulation necessary for the preservation of periodontal health.

34. 
Guidelines for occlusion in
dental treatment
 These guidelines are for
(1) pretreatment evaluation of dental occlusion,
(2) planning occlusal changes or fabricating dental occlusion in
treatment
(3) post-treatment evaluation of the dental occlusion.
 Based on
 Occlusal stability in ICP
 Maxillomandibutar Relationships and Tooth Contact
Movement
 Subjective Response to Occlusion

35. 
Guidelines for occlusion in dental
treatment
 Occlusal stability in ICP
1. Jaw closes to a repeatable, single end point.
2. Simultaneous masseter muscle contraction after
forceful clenching in the intercuspal position.
3. Simultaneous, widely distributed posterior tooth contacts.
4. Forces of tooth contact directed along the long axis of the
teeth

36. 
 Maxillomandibutar Relationships and Tooth Contact
Movement
6. Contact movement from RCP to ICP (mandibular shift) is
less than 1 mm (no shift is acceptable).
7. Laterotrusive side guidance primarily on the ipsilateral
canine-premolar teeth.
8. Protrusive guidance is symmetric.

37. 
 Subjective Response to Occlusion
10. Lack of unpleasantness towards the dental occlusion.
11. Acceptable free way space.
12. Acceptable speech articulation.
13. Acceptable chewing ability.
14. Acceptable mandibular position.

38. 
Indications for coronoplasty
 Existing occlusion and maxillomandibular relationship is
altered when it is anticipated that the resulting changes will
 (I) normalize the trauma from occlusion
 (2) result in occlusal stabilization for future restorative or
prosthetic procedures

39. 
Objectives of coronoplasty
• Change in pattern and degree of afferent impulses
• Reducing the excessive tooth mobility
• Multiple simultaneous tooth contact spread over the occlusal
scheme to effect occlusal stabilization
• Beneficial change in the pattern of chewing or swallowing
• Multidirectional mandibular movement patterns
• Verticalization of occlusal forces on tooth

40. 
Sequencing coronoplasty in
treatment planning
 Elimination of gingival inflammation and pocket depth
 Occlusal analysis
 Informed consent

41. 
Occlusal analysis
 Diagnostic models should be made.
 Mounting of casts on an articulator using facebow transfer
 Trial adjustment of occlusion on casts

42. 
Material used for occlusal analysis
• Occlusal registration strips
• Occlusal indicator wax
• Marking ribbon
• Articulating paper

43. 
Informed consent
 Patients are often concerned about whether coronoplasty will
change their appearance, cause tooth decay, or increase tooth
sensitivity.
 The clinician should explain that the teeth are not going to be
ground down, but reshaped so that they will function better.
 The reshaping is done in areas where tooth decay rarely
occurs. The patient should understand that the teeth and the
occlusion change with time and that minor adjustments will
be made on subsequent recall, if necessary.

44. 
Methods
I) Determing the end point of coronoplasty
 Selection of an intraborder position is logical, as there is little
doubt that the ICP (Intercuspal position) is the functional
point of the occlusion.
 RCP (Retruded cuspal position) adjustment is practical in
more complex cases, because RCP adjustment provides an
objective method by which to align the mandible.
 Ultimately, stability of the occlusion is more important than
whether RCP, ICP or the habitual closure position is selected
for the occlusal end point

45. 
II) Selecting occlusal guidance scheme.
1) Balanced occlusion
 Refers to the simultaneous contact between the right and
left posterior segments of the arch in lateral excursion of the
mandible and between the posterior and anterior segments
of the arch in protrusive excursion.
 The probable benefits include decreased dental loading
forces with bilaterally similar cuspal inclines.

46. 
2) Canine protected occlusion
 Where the maxillary canines act to guide the mandible so
that the posterior teeth come into closure will minimal
horizontal forces.
 In lateral and protrusive excursions, the mandibular canines
and first premolars engage the lingual surface of the
maxillary canines so as to disclude the incisors, premolars
and molars and protect them from undesirable horizontal
forces.

47. 
3) Group function
 It is the simultaneous gliding contact of teeth on the
laterotrusive side during laterotrusion.
 In group function, both functional and parafunctional
occlusal forces exceed those in canine function, so it is not
indicated for periodontally compromised dentitions.

48. 
Occlusal adjustments
Clinical goals
 To reduce the supra contacts so as to create unobstructed
closure of cusps into fossae and marginal ridges, while at the
same time conserving original crown structure
 The correction of occlusal supracontacts consists of
 Grooving
 spheroiding
 pointing

49.  Grooving:
• Done with a tapered cutting tool.
• Entails restoring the depth of developmental grooves.
 Spheroiding:
• Restores the original tooth contour while reducing the supra
contact.
• Done with a light paint brush stroke.
 Pointing:
• Consists of restoring cusp point contours.

50. 
Grooving

51. 
Spheroiding

52. 
Pointing

53. 
Sequence for coronoplasty
 STEP 1 Remove retrusive prematurities and eliminate the deflective shift
from RCP to ICP
 STEP 2 Adjust ICP to achieve stable ,simultaneous multipointed widely
distributed contacts
 STEP 3 Test for excessive contact (fremitus ) on anterior teeth
 STEP 4 remove posterior protrusive supra contacts and establish contacts
that are bilaterally distributed on the anterior teeth
 STEP 5 Remove or lessen mediotrusive interference
 STEP 6 Reduce excessive cusp steepness on laterotrusive contacts
 STEP 7 Eliminate gross occlusal disharmonies
 STEP 8 Recheck tooth contact relationship
 STEP 9 Polish all rough tooth surfaces

54. 
Remove retrusive prematurities and
eliminate the deflective shift from RCP to
ICP
 The purpose of this step is to reduce supracontacts that interfere
with posterior border closure of the mandible to a stable bilateral
RCP
 When contact is located on the retruded path of closure,
supracontacts may cause the mandible to deflect forward and
sometimes laterally into the ICP.
 This contact movement is termed the shift or slide from RCP to ICP
 Retrusive adjustment results in the elimination of the RCP-to-ICP shift

55. 

56. 

57. 
 Remove the inclines between RCP and ICP that cause
supracontacts when the mandible moves from RCP to ICP,
without removing the vertical stop or supporting cusp tip
 These inclines, called retrusive prematurties, are usually
found on mesial facing inclines of the maxillary teeth and
distal facing inclines of the mandibular teeth (MUDL rule)
 Preserve marginal ridges, adjust cusp tip as last resort.

58. 

59. 
 The retrusive range adjustment is complete when the
following conditions are achieved:
1. The contact pattern is bilateral with multi-pointed
contacts;
2. The deflective shift from RCP to ICP has been eliminated
3. Both RCP and ICP approach the same vertical dimension
of occlusion.
4. The pathway from RCP to ICP, if present, is smooth and
gliding.
5. Repeated closure of the teeth together in the hinge
position produces a sharp resonant sound.

60. 
Adjustment of the ICP
 The purpose of this step is to achieve a stable ICP and to refine
occlusal anatomic relationships
 The main feature of this step is that supracontacts are identified
without guidance by the operator's hand
 The alteration that commonly are made in conjunction with this
step are
 reduction of cuspal size
 alteration of occlusal table width,
 lessening of plunger cusp height

61. 

62. 

63. 
 The incisor tooth should be slightly out of contact or
in light contact over the maximum number of teeth.
 The mylar strip should just slip through the incisor
teeth in ICP.
 No fremitus should be detectable.
Test for excessive contact on the
incisor teeth in ICP

64. 
 The ICP adjustment is complete when
1. The contact pattern is bilateral, stable and many pointed
2. Each posterior vertical step holds a Mylar occlusal strip with
equal resistance
3. Sharp, resonant sounds are heard when the patient taps his
or her teeth together in ICP (with a stethoscope placed over
the infraorbital skin area
4. The patient responds negatively to the following question:
'Tap on your back teeth, slow and hard—do you feel any
difference between the two sides?"
5. No fremitus is detected in the anterior teeth.

65. 
Remove Posterior Protrusive Supracontacts;
Obtain Bilateral Protrusive Contact Movement
on the Anterior Teeth

66. 
Remove or lessen mediotrusive
(Balancing) supracontacts

67. 
Reduce supracontacts on the laterotrusive
(working) side

68. 
Eliminate undesirable gross
occlusal features

69. 

70. 
Recheck the tooth contact
relationship
 Tooth contact relationships in all positions and movements
are rechecked.
 Polish all rough tooth surfaces.

71. 
CRITERIA FOR JUDGING THE
OUTCOME OF CORONOPLASTY
There is no asymmetric shift from RCP to ICP. If a shift is present, it is smooth,
symmetric, and less than 1 mm in magnitude.
The completed adjustments have light contact or no contact between the incisor teeth
and firm contact between as many posterior teeth as possible.
The patient perceives "even" (bilateral) contact when closing the teeth to ICP.
Sharp occlusal sounds are produced when the patient taps slowly and firmly into
ICP.
Molar excursive supracontacts are neutralized or significantly reduced so that
unrestricted glide paths are available for the posterior cusps
Tooth guidance under lateral and protrusive excursion is smooth and without effort.
The displacement of mobile teeth is minimized under closure and gliding
movements.

72. 
Treatment of increased
tooth mobility
Situation I
 Increased mobility of a tooth with increased width of the
periodontal ligament but normal height of the alveolar
bone

73. 
Situation II
 Increased mobility of a tooth with increased width of the
periodontal ligament and reduced height of the alveolar
bone
 If the excessive forces are reduced or eliminated by occlusal
adjustment, bone apposition to the “pretrauma” level will
occur, the periodontal ligament will regain its normal width
and the tooth will become stabilized

74. 
Conclusion: situations I and II
 Occlusal adjustment is an effective therapy against increased
tooth mobility when such mobility is caused by an increased
width of the periodontal ligament.

75. 
Situation III
 Increased mobility of a tooth with reduced height of the
alveolar bone and normal width of the periodontal
ligament
 The increased tooth mobility which is the result of a
reduction in height of the alveolar bone without a
concomitant increase in width of the periodontal membrane
cannot be reduced or eliminated by occlusal adjustment.
 In teeth with normal width of the periodontal ligament, no
further bone apposition on the walls of the alveoli can occur.

76. 
 If such an increased tooth mobility does not interfere with
the patient’s chewing function or comfort, no treatment is
required.
 If the patient experiences the tooth mobility as disturbing,
however, the mobility can only be reduced in this situation
by splinting, i.e. by joining the mobile tooth/teeth together
with other teeth in the jaw into a fixed unit – a splint.

77. 
Situation IV
 Progressive (increasing) mobility of a tooth (teeth) as a
result of gradually increasing width of the reduced
periodontal ligament
 It will only be possible to maintain such teeth by means of a
splint. In such cases a fixed splint has two objectives:
(1) to stabilize hypermobile teeth and
(2) to replace missing teeth

78. 
 Splinting is indicated when the periodontal support
is so reduced that the mobility of the teeth is
progressively increasing, i.e. when a tooth or a group
of teeth are exposed to forces during function.

79. 
Situation V
 Increased bridge mobility despite splinting
 An increased mobility of a cross-arch bridge/splint can be
accepted provided the mobility does not disturb chewing
ability or comfort and the mobility of the splint is not
progressively increasing.

80. 

81. 

82. 

83. 
Conclusion
 Measurement of the outcomes from occlusal therapy usually
cannot be readily achieved.
 In cases where patient is experiencing discomfort from
occlusal contact, patient will experience relief from pain
when they are relieved from occlusal forces.
 In most cases , however, the changes can only be measured
in terms of decreased mobility and long term results to
periodontal therapy.

84. 
References
 Clinical Periodontology- Carranza 10thh Edition.
 Clinical Periodontology- Carranza 8th Edition
 Clinical Periodontology & Implant Dentistry – Jan Lindhe 4th
edition
 Management of Temporomandibular Disorders and
Occlusion- Jeffrey P. Okeson (4th edition)
 Functional occlusion – Peter E. Dawson 5th edition
 Walter . B . Hall – Critical Decisions In Periodontology
 Occlusal factors as a risk factor for periodontal disease Perio
2000, 2003; vol 32
 Occlusal analysis, diagnosis and management in the practice
of periodontal disease Perio 2000, 2004; vol 34

85. 
THANK YOU !!!