Wear 1 Flashcards
What are the types of tooth surface loss
Caries
Non-carious- wear, developmental disorders, trauma
What is physiological tooth wear?
Normal wear that occurs due to normal function (increases with age- may not require treatment)
-> 20-38 um per annum
What is pathological tooth wear?
Remaining tooth structure or pulpal health is compromised OR the rate of tooth wear is in excess of what would be expected for that age
->It can also be considered pathological if the patient experiences a masticatory or aesthetic deficit
What are the causes of tooth wear?
Attrition
Abrasion
Erosion
Abfraction
What is attrition?
The physiological wearing away of tooth structure as a result of tooth to tooth contact
What are the features of attritive wear?
Found on occlusal and incisal surfaces
Appears as polished facets on cusps or flattening of tips
Gradually begins to cause shortened cusp/crown length and flattened occlusal planes
What is the main cause of attritive wear?
Parafunctional habits- bruxism
In attritive wear how do restorations wear in comparison to tooth tissue?
The same amount
What is abrasion?
The physical wear of tooth substance through an abnormal mechanical process independent of occlusion (It involves a foreign object or substance repeatedly contacting the tooth)
What is the site/pattern of abrasive tooth wear related to?
Where the abrasive object is used or applied
-> most common areas are labial and buccal regions (cervical on canines and premolars)
How do abrasive lesions appear?
V-shaped or rounded
-> sharp line where enamel and dentine meet (scalloped appearance)
Notching on incised edges
What are the causes of abrasive lesions?
Toothbrushing (most common)
Habits- biting pins, nails, electrical wire stripping, fishing line, thread, pipe smoking, ecigs
Why may ecigs cause abrasive wear?
They are heavy and getting heavier
The liquid they use is acidic
What is erosion?
The loss of tooth surface by a chemical process that does not involve bacterial action
-> most common wear and increasing in prevalance
What typically causes erosion?
Exposure of teeth to acidic substance (can be intrinsic or extrinsic)
What occurs in the early stages of erosion?
There is loss of surface detail, surfaces become flat and smooth
-> lesions appear concave and are usually bilateral
How can erosion be differentiated from bacterial acid decalcification?
Lesions do not have chalky white appearance around margins
What occurs in the later stages of erosion?
Dentine becomes exposed
Preferential wear of dentine leads to ‘cupping’ of the occlusal surfaces of the molars and incisal edges of the anteriors
What is severity of erosion based on?
Source, type and frequency of exposure to the acid.
How does erosion appear?
Cupping of teeth (deepest part does not contact opposing tooth)
Increased translucency of incisal edges (darkening)
No tooth staining (washed away by acid)
Rings of enamel around dentine
Restorations sitting proud of tooth
What is abfraction?
The loss of hard tissue from eccentric occlusal forces leading to compressive and tensile stresses at the cervical fulcrum areas of the tooth
-> Typically appears as loss of tooth substance at cervical margin
What causes abfraction? (theory)
Caused by biomechanical loading forces:
->Forces result in flexure and failure of the enamel and dentine at a location away from the loading
-> Disruption of the ordered crystalline structure of the enamel and dentine by cyclic fatigue (causing cracks and ‘chipping out’ of tooth substance)
How does abfraction appear?
V shaped tooth loss (sharp) where the tooth is under tension
-> classically buccally at ACJ in premolars and molars
What are the causes of cervical wear?
Multifactorial:
Overzealous toothbrushing
Combination of erosion, abrasion and abfraction
What are the epidemiological issues with tooth wear?
Overall the incidence is increasing
Difficult and Demanding to treat
Expensive for the patient
Expensive for the NHS
What should be done when assessing tooth wear?
Recognise the problem is present
Grade severity
Diagnose the likely cause or causes
Monitor the progression of the disease- is it active or historic?
What do patients tend to complain about when they present with tooth wear?
Poor aesthetics
Functional issues- poor masticatory efficiency, biting tongue/lips
Pain- if rapidly progressing/pulpal involvement
Why does wear tend not to cause pain?
In normal slowly progressing wear- secondary dentine is laid down and causes pulp to retreat further into tooth
What aspects of a patients medical history could be related to or causing tooth wear?
Medications with low pH
Medications which dry the mouth
Eating Disorders
Alcoholism
Heartburn
GORD (patient not always aware)
Hiatus Hernia
Rumination
Pregnancy (reflux/morning sickness- transient)
-> consider referral to GMP for treatment
What aspects of a patients social history may be contributing to tooth wear?
Lifestyle stresses/occupation- Bruxism
Alcohol consumption
Diet
Habits
Sports- gels in endurance athletes
What should be checked for in an EO examination when assessing the patient for tooth wear?
TMJ - restriction of movement, clicking, crepitus
Examine musculature for hypertrophy
Examine mouth opening for restriction (<4cm) and deviation during movement
Parotid hypertrophy- bullimia
Overclosure
Lip Line
Smile line
What should be checked when examining the occlusion of a patient in a wear assessment?
Freeway space
Record the OVD and resting face height
-> Has their been dento-alveolar compensation
Record overbite and overjet
Stable contacts in centric relation/excursive movements
Why may freeway space remain normal even in patient with excessive wear?
As wear is such a slow process:
Dentoalveolar compensation- bone grows down as teeth wears (takes teeth with it), incisal level stays similar
What can dentoalveolar compensation due to wear result in?
Can result in different orthodontic relationships- can become more class III
What can be done to treat wear in patients which is caused by excursive movement?
Give them canine guidance back (wear down composite rather than patient’s teeth)
What other IO checks should be done in a wear assessment?
Soft Tissues- dryness, buccal keratosis or lingual scalloping
Oral Hygiene
Perio assessment BPE +/- pocket chart
Dental charting
What condition causes wear in the anterior and palatal regions?
Bullimia
What does BEWE stand for?
Basic Erosive Wear Examination
BEWE classification:
0= No erosive wear
1= Initial loss of surface texture
2= Distinct defect-hard tissue loss <50% of surface
3= Hard tissue loss >50% of the surface area
What special tests may be useful when assessing tooth wear?
Sensibility testing- if wear may cause pulpal issues
Radiographs
Articulated study models
Intra-oral photographs
Salivary analysis
Diagnostic Wax-up- show potential results of tx
Dietary analysis
