📚 - tooth surface loss and GIT

erosion and aetiology

* The loss of enamel and dentine primarily from chemical attack other than those chemicals produced intra orally by bacteria


* direct acid contact of the teeth
* aetiology is exposure to acids through diet and GIT

submargination

* surrounding tooth is much lower than current restoration placed as acid has eroded the surrounding tooth

dentine hypersensitivity

* dentine underneath is exposed
* dentine is tubular structure so hot or cold liquid causes movement in the dentinal tubules which is picked up by the pulp nerve causing sensitivity

corrosive process

* gradual destruction of material, usually metal, by chemical reaction with its environment

chemistry of erosion

* acid enters the mouth (H+) it must–
* Diffuse through plaque and pellicle
* Penetrate the protein/lipid coating of individual hydroxyapatite crystals that make up the enamel
* imperfect apatite (Ca10-xNax(PO4)6-y(CO3)z(OH)2-uFu) is more acid soluble than pure Hydroxyapatite (Ca10(PO4)6(OH)2) as a result more susceptable to acid erosion

Crystals in dentine

**once acid reaches the dentine it speeds up erosion process as**

* crystals in dentine smaller than enamel


* Surface area per g of dentine is much higher than in enamel
* Enamel carbonate content approx 3 % cf. dentine 5-6%
* As a result dentine more acid soluble

acid (H+) mode of attack

* Dissolve by combining with carbonate/phosphate ion (direct surfaceetching)
* Complex with calcium to remove from lattice (surface softening)
* Subsurface softening gives opportunity to repair and reverse process by remineralisation

Aetiological Factors

* Extrinsic
* Intrinsic

Intrinsic Aetiological Factors

Gastric contents reach oral cavity by

* Vomiting
* Regurgitation
* Gastroesophageal reflux
* Rumination

Erosion Risk when vomiting - 1937 by Bargen and Austin theory

* increase risk x4 if weekly regurgitation
* increase risk x16 with chronic vomiting

Vomiting

* The forceful expulsion of gastric contents through the mouth
* Common manifestation of many organicand psychosomatic disorders

Organic and psychosomatic disorders associated with vomiting

* Disorders of GIT
* CNS disorders with raised intracranialpressure
* Neurological disorders
* Metabolic and endocrine disorders - undiagnosed diabetes (excessive thirst and drinking a lot of fizzy drinks for sugar)
* Psychosomatic disorders
* Drug side effects

how does Regurgitation & Reflux differ from vomiting

* Lack of diaphragmatic muscularcontraction
* Relatively small quantity of materialejected
* Generally associated with increased gastric volume and pressure (^^with age spinchters may not work efficiently therefore more susceptable to regurgitation)^^

Rumination

* Special form of regurgitation
* gastric contents regurgitated, chewed and re-swallowed

Biological factors modifying the erosion process

* Saliva
* Tooth composition and structure
* Dental anatomy and occlusion
* Soft tissue anatomy and physiologicalfunction

Saliva

* Dilution and carries out clearance
* Neutralisation and buffering
* Maintenance of supersaturated state next to the tooth surface of calcium and phosphate
* assists in Acquired pellicle formation - layer that acid has to penetrate, this layer is protected against erosion
* Provision of Ca, Phosphate and Fluoride for remineralisation

Dental anatomy and occlusion

* Tooth prominence - in relation to drinking/swallowing patterns


* Dental occlusion may influence abfraction (the chipping of enamel at the gingival margin)- cervical area then more susceptible to erosion

Soft tissue anatomy and function

* Influence areas that acid contacts
* Influence clearance pattern
* Most severe erosion generally found on the palatal surfaces of teeth that touched by the tongue - if softened by acid tongue will have rasping action, over time will remove a degree of tooth surface

Importance of erosion

* Eating disorder (AN,BN, EDNOS, BED)
* Psychological wellbeing
* Medical risk
* Suicide risk

Eating disorders

* Denial and shame strongly associated
* Attempt to conceal condition
* Look out for unexplained weight loss, abdominal and gynaecological problems, sleeping lethargy and fatigue
* Sore throat from recurrent vomiting

Anorexia nervosa (AN)

* Significant mortality 4-20%
* Prevalence 0.1 to 1% of young females
* Average age of presentation 16 years old
* Incidence (no. new cases/year) 7 per 100,000
* Duration up to 6 years
* Medical complications and predispositionto suicide
* Disturbed perceptions of body shape and size
* Obsession with self image
* Restricting/binge or purge types

Bulimia nervosa (BN)

* Recurrent episodes of binge eating followed by inappropriate behaviours to avoid weight gain
* Average age 25 years old
* Prevalence 1 to 2 % adolescent girls & 0.1% young men
* Incidence 8 to 14 cases per 100,000
* Purging – self vomiting
* Non purging – permutations of excessive exercise and fasting
* Uni/multi impulsive bulimia – in addition drug abuse, shop lifting and aberrant sexual practices
* Suicide risk greater than AN
* Better recovery than AN – 80%
* Death in 0.3% of cases

Eating disorders not other wise specified (EDNOS)

Misfit classification

Binge eating disorder (BED)

* Prevalence 1% affecting M & F equally
* Within 10% of normal weight
* Outwardly obese/overweight
* More prone to acid reflux as a result

GORD - gastro oesophgeal reflux disease

* Oesophagitis– inflammation of the oesophagus
* Barretts epithelium - can transform into cancer
* Oesophageal adenocarcinoma –
* Aspirational pneumonitis - acid can enter lungs as cause damage

Spechler questionnaire

7 day diary

* Times of heartburn
* Severity ofoesophageal discomfort
* Difficulty swallowing
* Coughing/wheezing– Weighted and scored to yield severity

this detects

* Those with reduced medical control of reflux that were once controlled well
* Those who thought reflux was normal
* Those who did not know they had a reflux problem

The CAGE Questionnaire - for alcoholism

* Have you ever felt you ought to Cut down on your dinking?
* Have people Annoyed you by criticising your drinking?
* Have you ever felt bad or Guilty about your drinking?
* Have you ever had a drink first thing in the morning to steady your nerves or get rid of a hangover (Eyeopener)?

The SCOFF questionnaire

* Do you make yourself feel Sick because you feeluncomfortably full?
* Do you worry you have lost Control over how much youeat?
* Have you recently lost more than One stone in a threemonth period?
* Do you believe yourself to be Fat when others say youare too thin?
* Would you say that Food dominates your life?
* One point for every YES score. A score of > 2 indicatesa likely case of anorexia/bulimia.