1. South West Post Graduate Dental Deanery DCP Advisor Devon/Cornwall
Tooth Tissue Loss - Erosion, Abrasion, Attrition and Abfraction; we wonder why our teeth are sensitive!
Sonia Jones RDH CFET
South West Post Graduate Dental Deanery DCP Advisor Devon/Cornwall

2. Aims and Objectives
Aim: to ensure delegates understand how tooth tissue loss can be detrimental to dentine hypersensitivity
Objectives:
By the end of the session you should be able to:
Distinguish between erosion, abrasion, attrition and abfraction
Determine the causative factors of tooth tissue loss
Describe how to prevent further tooth tissue loss
Discuss sensitivity theories and explain the way they work
List topical medicaments available to relieve sensitivity

3. Tooth tissue loss Tooth surface loss can arise as the result of:
Erosion
Abrasion
Attrition
Abfraction

4. Erosion

5. Abrasion

6. Attrition

7. Abfraction

8. Tooth tissue loss Patients often seek treatment for pain
Function can be altered
Compromised aesthetics
All ages

9. Tooth tissue loss
The 4 types of tooth tissue loss all have their own characteristic appearance
However, the wear of a persons teeth is usually from a mixture of all 4, with one type of TTL predominating.
Sometimes difficulty in determining the dominant aetiology
The thickness of the pellicle and the pressure of the tongue contribute to the extent of the condition

10. Tooth Tissue Loss Relatively slow progression Study models Indices
Photographs
Can all be helpful
Restorative treatment
Difficult to control
Very different to dental caries in appearance and causation

11. Erosion Described as early as 1892 among Sicilian lemon pickers
Definition: ‘The loss of tooth tissue by a chemical process that does not involve bacteria, acids are most commonly involved in the dissolution process’
Non carious pathological loss of tooth tissue
Plaque not involved in the process

12. Clinical Presentation
Occurs most frequently on the palatal and labial surfaces of the incisor teeth
The effected surfaces appear smooth and highly polished with a scooped out depression
The lesion primarily occurs in the enamel
In more severe cases the dentine becomes exposed
As enamel loss progresses sensitivity to thermal changes are noticed
More persistent pain occurs in severe cases

13. Erosion

14. Erosion

15. Causes of erosion Extrinsic factors Intrinsic factors
Idiopathic factors

16. Extrinsic causes of erosion
Habitual consumption of highly acidic, low pH carbonated drinks, sports drinks or concentrated fruit juices
Alco pops, fruit flavoured alcoholic beverages and strong ciders
Causing a wide shallow lesion effecting the labial and palatal surfaces of the upper teeth

17. Extrinsic causes of erosion
Swishing or holding drinks in the mouth
Modern packaging has also been blamed, tetra pack, plastic bottles and cans – directional flow onto teeth
Can extend from the labial and palatal lesions of the upper teeth to all surfaces of all teeth

18. Chemicl pH

20. Acids involved
The principal ingredient linked with erosion is citric acid, found in most fruit juices and soft drinks
Other fruit acids have an effect
The erosive effect is due to its low chemical pH
Also by ‘chelation’, the acids demineralise the enamel by binding to the calcium and removing it from the enamel
Cola type drinks may also contain phosphoric acids
While the pH of a drink is an indicator of its erosive potential, a measure called ‘total titratable acidity’ is a better guide of how a liquid can dissolve a mineral

21. Total Titratable Acidity

22. Titratable acidity How long it takes for the saliva to compensate
How much saliva (flow)
Buffering capabilities of the saliva
Citric acid the biggest culprit
Thickness of the pellicle can protect to a degree
Higher temperatures increase titratable acidity

23. Extrinsic causes of erosion
Habitual sucking of citrus fruits
The lesion may occur in either the upper or lower anterior teeth
Depending on the way the fruit is eaten
(Remember fruit eaten as a whole unit does not generally cause a problem)
Acidic foods
Pickles, sauces, vinegars, yoghurts, roasted vegetables

24. Extrinsic causes of erosion
Industrial atmospheric pollution
Chemical workers, battery manufacturers, crystal glass workers
Less common now due to stricter working conditions and regulations (H&S at work act 1978)
Acidic fumes effect the labial surfaces of the upper and lower anterior teeth
When talking or the mouth is at rest

25. Extrinsic causes of erosion
Chlorine, from gas chlorinated swimming pools
Professional swimmers
If the chemicals are not properly regulated
Less common now due to regulations

26. Intrinsic causes of erosion
From within the body
Usually hydrochloric acid from the stomach (pH 2)
Reflux
Regurgitation
Vomiting
Rumination

27. Rumination
The term rumination is derived from the Latin word ruminare, which means to chew the cud. Rumination is characterized by the voluntary or involuntary regurgitation and rechewing of partially digested food that is either reswallowed or expelled. This regurgitation appears effortless, may be preceded by a belching sensation, and typically does not involve retching or nausea.

28. Reflux, Regurgitation and Vomiting of gastric contents
Anorexia
Bulimia
Hiatus Hernia
Pregnancy/Hormones
Motion sickness
Obesity
Eating too much
Drinking too much
Alcoholism

29. Anorexia

30. Bulimia

31. Saturday Night?

32. Habitual regurgitation of gastric contents
Heavily acidic diet increases gastric erosion
The palatal surfaces of the upper anteriors and premolars are eroded
Produces wide shallow lesions
Enamel may be completely lost
Tackle the problem with care!
Patient might not admit to unattractive aspect of psychological illness

33. Idiopathic causes of erosion
Unknown cause
Patient will not admit to or be aware of intrinsic or extrinsic causes
Vigorous tooth brushing can contribute to an over polished appearance - shiny

34. Abrasion
Definition: ‘The abnormal wearing away of tooth tissue by a mechanical process’
The location and pattern of abrasion is directly dependent upon its course
It usually occurs on the exposed root surfaces when gingival recession has exposed the cementum
It may be seen on the incisal or inteproximal surfaces of the teeth

35. Causes of Abrasion Incorrect or destructive use of a toothbrush
Use of an abrasive detrifice
The enamel and dentine is worn away to produce a ‘V’ shaped notch at the neck of the tooth
Areas most affected are the labial and buccal surfaces of the canines and premolars
Powerful back hand, RHS of right handed person
LHS of Left handed person
Para functions, habits, occupations
Mainly affects the incisal edges of the anterior teeth

36. Clinical appearance of Abrasion
Worn, shiny often yellow/brown areas at the cervical margin
Worn ‘notches’ on the incisal surfaces of the anterior teeth

37. Abrasion

38. Abrasion

39. Causes of Abrasion
Seamstresses – pins, Carpenters – nails, Hairdressers – hairgrips
Pipe smokers, nail biters, causing ‘notching’

40. Attrition
Definition: ‘The physiological wearing away of the tooth surface as a result of tooth to tooth contact’ as in mastication
Occlusal and incisal surfaces of the teeth most commonly affected
May also affect the proximal surfaces of the teeth due to slight movement of the teeth in their sockets during mastication
Age related process
Varies from person to person

41. Attrition Causes: Bruxism Abrasive (gritty) diet
Constant chewing – tobacco/ betel nut
Marked malalignment or malocclusion
Loss of posterior teeth
Occupational, dust/grit mixed with saliva

42. Clinical appearance of Attrition
Polished facets on enamel surfaces
Cupping – dentine is exposed
Occasional full loss of enamel, dentine is exposed and stains heavily

43. Attrition

44. Attrition
Ranges from part of the enamel being worn away in the early stages to the full thickness of the enamel wearing away in advanced attrition
The dentine may be exposed and stained
In extreme cases the teeth may be worn down to the gingivae

45. Attrition

46. Attrition Process of attrition is slow
Secondary dentine is laid down to protect the pulp chamber and the pulp chamber narrows
Pain is rarely associated with attrition
Men usually show a greater degree of attrition than women
Severe attrition is seldom seen in deciduous teeth, (not retained for long)
However if a child suffers from dentinogenesis imperfecta (an hereditary disorder of the dentine) pronounced attrition may result from mastication

47. Abfraction
Definition: ‘The pathological loss of enamel and dentine due to occlusal stresses’
Recently interest has grown in the development of cervical abrasive lesions
The term abfraction has been used to describe these cervical lesions
Some Clinicians do not believe that this is the reason and that erosion and abrasion cause the wear facets, research continues

48. Abfraction

49. Causes of Abfraction
Occlusal forces which cause the tooth to flex, cause small enamel flecks to break off, inducing the abrasive lesions
Usually wedge shaped lesions with sharp angles found at the cervical margins
However can be found on the occlusal surfaces, presenting as circular areas
These lesions can occur with occlusion alone or as with most TTL cases which are multi factorial, can be associated with toothbrush abrasion
These lesions are often diagnosed as toothbrush abrasion, but they differ as their angles are sharper

50. Abfraction Common in patients with poor tooth alignment
Can be associated with:
Anterior open bite
Occlusal restorations that change the cuspal movements
Abnormal tongue movement

51. Treatment of Tooth Tissue Loss
Relieve sensitivity and pain – fluoride, desensitising agents/toothpastes
Identify aetiological factors – modify diet/habits, eliminate acidic foods/drinks, stop habitual practices, gentle tooth brushing techniques
Protect the remaining tooth tissue – reconstruct the effected teeth, restorations, inlays/onlays, crowns, check occlusion
Bite raising devices/splints
Referral to TTL Expert
Prevention of further episodes

52. Treatment Plan Take a detailed history from the patient Examination
Radiographs
Vitality testing
Patients wishes/needs
Study models
Photographs
Indices

53. Indices BEWE Basic Erosive Wear Examination 0 No Erosive Wear
1 Initial loss of Surface texture
2 Distinct defect, hard tissue <50% of the surface area
3 Hard tissue loss >50% of the surface area
* (2,3) dentine involved

54. Tooth wear index according to Smith and Knight
Score Surface Criteria
0 B/L/O/I No loss of enamel surface characteristics
C No loss of contour
1 B/L/O/I Loss of enamel surface characteristics
C Minimal loss of contour
2 B/L/O Loss of enamel exposing dentine for less than one-third of
the surface
I Loss of enamel just exposing dentine
C Defect less than 1mm deep
3 B/L/O Loss of enamel exposing dentine for more than one-third
of the surface
I Loss of enamel and substantial loss of dentine
C Defect less than 1-2mm deep
4 B/L/O Complete loss of enamel, or pulp exposure, or exposure of
secondary dentine
I Pulp exposure or exposure of secondary dentine
C Defect more than 2mm deep, or pulp exposure, or exposure
of secondary dentine

55. Sensitivity
Dentine Hypersensitivity – Dentine is the highly sensitive part of the tooth Patients suffering from dentine hypersensitivity often think that they have developed a cavity or lost a filling On examination there is often no obvious reason for their pain, gingival recession is sometimes evident The amount of recession does not seem to correlate with the amount of pain they are experiencing c/o short sharp episodes of pain caused by temperature, touch by metal, sweet foods/drinks Patients can be very distressed by the pain of dentine hypersensitivity and often avoid the causative stimuli as much as possible

56. Sensitivity Women more pre disposed than men Age 20-40
Ranges from 15-70

57. Dentine Made up of dentinal tubules
Looks like honeycomb under the microscope
Similar in composition to bone
Can remodel itself and lay down reparative and secondary dentine
When exposed to the oral environment can be sensitive

58. Dentine
Larger tubules = more pain
More open tubules = more sesitivity

59. Dentinal tubules

60. Dentine Hypersensitivity Theories
3 theories as to how we feel the pain of dentine hypersensitivity
Dentine Innervation Theory
Odontoblast receptor theory
Hydrodynamic theory

61. Dentine Innervation Theory
Nerve fibres from the Nerve Plexus of Raschkow (next to the dentine /pulp boundary, along side the Odontoblast activity) penetrate the dentinal tubules and cause impulses Not the most likely theory: whilst the nerve fibres do penetrate the tubules, there are not enough of them and they do not penetrate deeply enough into the tubules to pass on impulses

62. Odontoblast Receptor Theory
Proposes that Odontoblasts receive and pass on impulses and that when they are touched cause the sensation of pain Not the most likely theory: as there are no synapses between the Odontoblasts and the Nerve Plexus of Raschkow (Synapses – junctions between neurones where chemicals transmit the impulse)

63. Hydrodynamic Theory Most likely theory: Answers more questions
Lymph like fluid inside the dentinal tubules is stimulated by temperature, touch and sweet sensations, causing it to flow backwards and forwards within the tubules, this gives the sensation of pain
Hot/cold causes expansion/contraction causing the fluid to flow
Salt/sweet causes osmotic pressure, flows towards the concentrate
Tactile/Electrical (Touch) ?! – contraction of the fluid?
Research continues, what they do know is how to treat it

64. Dentine Hypersensitivity Treatments
Most commonly treated by:
Mechanical Barriers
Stimulation of Peritubular or Reactive Dentine
Increasing potassium concentrations

65. Mechanical Barriers Applied over the open ends of the Dentine Tubules
Restorations – Glass ionomers, Composites, Inlays/Onlays, Dentine bonding agents that form a chemical bond with the dentine locking into the tubules, Resins/Adhesives
Tubule occluding toothpastes – need to be replaced daily

66. Stimulation of Peritubular or Reactive Dentine
The dentine lays down a protective layer
High concentration fluoride – Duraphat Varnish, Gel Kam (Fluorigard gel)
Siloxane Esters – Tresiolan, Sensitrol etc
Both will wear off so need to be reapplied

67. Fluoride Fluoride irritates the dentine
It irritates the dentine sufficiently for it to lay down a secondary layer and therefore protect the tooth from further stimuli
It does this by occluding the tubules
Mouthwashes daily 0.05% and weekly 0.2% solutions
High fluoride toothpastes - Duraphat 2800, 5000
Varnishes – Duraphat 2.26% 22,000ppm
Gels – 0.4% stannous fluoride

68. Increase Potassium Concentrations
Nerve Depolarising
Potassium chloride, Potassium Nitrate, Potassium Citrate found in desensitising toothpastes increase the potassium concentrations around the nerve plexus
This prevents action potentials being transmitted (nerve impulses)
By keeping the sodium outside the cell wall

69. Nerve Impulses Sodium is attracted to Potassium
By increasing the Potassium levels outside the nerve cell walls, the Sodium stays outside and doesn’t diffuse in
This stops the nerve impulse
Depolarisation

70. Action Potentials – Nerve Impulses

71. Sodium Potassium Exchange

72. Toothpaste Claims Nerve Depolarising Toothpastes
Tubule Occluding Toothpastes
Each manufacturer claims that their toothpaste has the best technology
Do they work?

73. Sensodyne Traditionally Nerve depolarising toothpastes
Active ingredients :
- Potassium Nitrate + Sodium Fluoride
- Potassium Chloride + Sodium fluoride
Potassium keeps the sodium outside the cell wall
By adding the fluoride to the newer types of Sensodyne you get the tubule occlusion phenomenon caused by dentine irritation and laying down of a secondary layer

74. Sensodyne Pronamel Claims to – reharden softened enamel
- be low in abrasives to prevent further tooth tissue loss
Active ingredient – Potassium Nitrate + Sodium Fluoride ?

75. Sensodyne new Occluding toothpaste
Sensodyne Rapid Relief
Active Ingredient Strontium Acetate + Sodium Mono-fluorophosphate
Published studies support the mode of action and tubular occlusion occurs
but:
Strontium Chloride – Sensodyne Original, occludes tubules! However as it reacts with fluoride became less popular

76. Colgate Sensitive Pro Relief

77. Pro –Argin Technology
Active Ingredients: Arginine, Calcium Carbonate, Hydroxyapatite, Sodium Mono-fluorophosphate
The Arginine complex binds to the tooth surface, it is positively charged this is attracted to the negatively charged dentine
It encourages a calcium rich mineral layer into the open (exposed) dentine tubules
This acts as an effective plug (tubular occlude)
Resistant to acid attacks
Needs to be reapplied twice daily

78. Other Brands
Enamel Care toothpaste - Amorphous Calcium Phosphate ACP (soluble salts of Calcium and Phosphate): highly soluble and there is limited data in the treatment of Dentine Hypersensitivity Recaldent (Toothmoose) – CCP-ACP Casein Phosphates, derived from milk proteins mixed with the calcium and phosphate salts: no apparent published clinical data on its effects of reducing Dentine Hypersensitivity Blanx, Biorepair- Hydroxyapatite + Sodium Mono-fluorophosphate: tubular occlusion but limited published data

79. Monitoring Treatment of active tooth tissue loss
Fluoride toothpastes/ mouthwashes/gels
De sensitising toothpastes
Study models
Photographs
Indices
Identify causative factors

80. Prevention Limit acidic food and drink to meal times
Eliminate from diet
Cut down on carbonated beverages
Eat citrus fruits whole not sucked in 1/4s
Do not hold/swish drinks
Use a straw
Refer to specialist
Refer to councillor for eating disorders/alcohol addiction
Refer to GP – gastric problems
Milk or cheese after meals to neutralise acids
Avoid toothbrushing after an acid attack

81. Aims and Objectives
Aim: to ensure delegates understand how tooth tissue loss can be detrimental to dentine hypersensitivity
Objectives:
By the end of the session you should be able to:
Distinguish between erosion, abrasion, attrition and abfraction
Determine the causative factors of tooth tissue loss
Describe how to prevent further tooth tissue loss
Discuss sensitivity theories and explain the way they work
List topical medicaments available to relieve sensitivity

82. Thank you