TEETH HYPERSENSITIVITY · hypersensitivity remains for several weeks the root canal treatment is recommended. A direct pulp capping is considered successful if the tooth is a symptomatic

TEETH

HYPERSENSITIVITY

What is Teeth Hypersensitivity

Etiological factors

Diagnosis

Management

Definition

An exaggerated response to a sensory stimulus that usually causes no response in normal healthy teeth

That stimulus can be tactile, thermal, electrical or chemo-osmotic stimulation

• Prevalence:

- Between 60 and 98% in patients with periodontitis.

- Transient hypersensitivity may occur after

periodontal procedures as (deep scaling, root planning

or gingival surgery).

- May occur after teeth whitening or restorative

procedures.

- Peak age (20-40 y.) - females ˃ males

Mechanism of dentin hypersensitivity:

1- neural theory

2- odontoblastic trasduction theory

3- hydrodynamic theory

ETIOLOGICAL FACTORS

I) Preoperative etiological factors: a) Bacterial

b) Chemical - Osmotic

c) Mechanical

d) Thermal

e) Idiopathic

II) Post operative (Iatrogenic): a) Cavity preparation.

b) Restorative phase and restorations.

c) Vital teeth bleaching.

I) Preoperative etiological factors:

a) Bacterial b) Chemical - Osmotic

c) Mechanical

d) Thermal

e) Idiopathic




Dental caries

Produces different levels of teeth hypersensitivity that is mainly related to:

The depth of decay.

Dentin conductance.

Pain threshold of the patient himself.

1- Depth of decay:

Caries in enamel involve no or little hypersensitivity.

In dentin is characteristic to be short and sharp pain arising from exposed dentin in response to stimuli.

Dull ache pain: if pulpal changes occur which might involve an irreversible pulpitis.

2-Dentin conductance

Deeper in dentin and near the pulp:

no of D.Ts., diameter, length,

permeability and consequently the

degree of hypersensitivity.


b) Chemical - Osmotic c) Mechanical

d) Thermal

e) Idiopathic




Erosion:

The dissolution of teeth by acids which

are not of bacterial origin.

Acids or osmotic agents like sugar when

adhere to the margins of leaky

restoration or exposed dentin, it will

cause flow of dentinal fluid

hypersensitivity.

I- Extrinsic erosion

Citrus fruits.

Pickled food.

Fruit juice.

Carbonated drinks.

I- Extrinsic erosion

Wines.

Vitamin C.

Mouth rinses with

low PH.

Bleaching agents.

Results from gastric reflux as in Hiatus

hernia, alcoholism, eating disorders like

bulimia nervosa

In case of intrinsic erosion the palatal

aspect of the upper anterior teeth and the

occlusal and buccal surfaces of the lower

posterior teeth are primarily affected.

II- Intrinsic erosion

Intrinsic erosion as a result of gastric reflux and vomiting

Intrinsic erosion as a result of

eating disorder



c) Mechanical d) Thermal

e) Idiopathic




Mechanical factors

i) Attrition

ii) Bruxism

iii) Abrasion

iv) Abfraction

v) Gingival recession

vi) Cracked tooth syndrome

vii) Trauma

1-Attrition

Wear at sites of direct contact between teeth.

Attrition is associated with normal occlusal function

and can be aggravated by habits or parafunctional

activities which is known as bruxism

The bruxism results in hypersensitivity to

heat and cold, fractured teeth and fillings,

myofacial pain, headache, stiffness and

pain in the joints and earache.

2-Bruxism

3-Abrasion

The wear of teeth caused by objects other

than teeth (toothbrush, tooth paste, pipe

smoking…)

The wear of teeth at the cervical

portion as a result of occlusal loading

that leads to cuspal flexture

4- Abfraction

5-Gingival recession

Result from malbrushing, malocclusion, excessive brushing and flossing.

Results in exposure of cementum which will lead to exposure of dentin and hypersensitivity

6- Cracked tooth

syndrome:

• Incomplete fracture of the teeth

• Involving dentin only or extending to pulp

• Resulted in teeth hypersensitivity with

biting relieved with releasing.

• Can happen in sound teeth especially

upper premolars (steepness), or most

commonly in teeth that is restored with big

restoration

7- Trauma

fracture of enamel Fracture of root Fracture of E. & D.



c) Mechanical

d) Thermal

e) Idiopathic




Reversible hypersensitivity

It subside by treating the exposed dentin

Irreversible hypersensitivity

It might require root canal treatment or

even extraction of the teeth in some severe

cases.



c) Mechanical

d) Thermal

e) Idiopathic

II) Post operative (Iatrogenic):

a) Cavity preparation. b) Restorative phase and restorations.


i. Cutting instruments

Rotary instruments produce more heat generation than the hand instruments.

Dull instruments require higher pressure and subsequently more heat generation

Heat can destruct pulpal tissue, coagulate protoplasm and even burn dentin and hence proper cooling is mandatory.

ii. Instrumentation pressure: Cause heat generation and might cause

actual aspiration of odontoblastic nuclei into the tubules

iii. Vibration: Cause a rebound response as a result of

using eccentric burs, which can result in necrotizing effects on dentin

iv. Dentin Desiccation: Can result from:

- Heating of dentin during cutting.

- Use of chemicals to sterile the cavity.

- Use of air as a coolant for final cavity toilet.

v. Actual cutting in dentin: Every square millimetre of dentin cut

exposes 30,000 to 45,000 dentinal tubules with resultant fluid movement in each one of them stimulating nerve damage.



c) Mechanical

d) Thermal

e) Idiopathic


b) Restorative phase and rest. c) Vital teeth bleaching.

*Polymerization shrinkage *Undercured resin

*Microleakage *Inadequate liner and/or base

*Fractured restoration *Cracked tooth

*Galvanism *Finishing Procedures

*Faulty occlusal and/or proximal relationship

*Gingival reaction to the rest. procedure and rest.

*Pulpal reaction to the rest procedure and rest.

*Local anesthesia *Barodontology

Restorative phase and restorations


1) Polymerization shrinkage Polymerization shrinkage

results in stresses at the

interface resulting in

microleakage, microcracks

and secondary caries.

C factor.

2) Undercured resin

Incompletely cured inner layer, results in

marginal fracture, open margin and chemical

toxicity.


3) Microleakage:

Ingress of fluids and microorganisms cause

dentinal hypersensitivity due to dentinal fluid

movements.

4) Inadequate protection: Metallic restoration cause

hypersensitivity specially in

first few days. Pain is elicited

with hot or cold application and

relieved with removal of the

stimulus.


5) Fractured restoration: Exposed dentin, recurrent

caries and dentin

hypersensitivity.

6) Cracked tooth: Sharp pain on biting and eating

citrus fruits, Large restorations

and restorations without cusp

protection .


7) Galvanism

Hypersensitivity is usually

felt in tooth containing the rest.

with the lower potential

i.e: Amalgam.

The degree of hypersensitivity depends on:

1- Difference in electrical potential.

2- Electrical resistance of dentin.

3- Presence and thickness of base.

4- Current intensity.

5- Pulpal condition and patient threshold.


8) Faulty occlusal and/or proximal relationship

Occlusal contact if high will affect the

periodontal ligament and lead to

sensitivity with bite and/ or mobility.

Proximal contact if tight will result in

excessive pressure that might result in

pain and interproximal bone resorption

and damage of the supporting structure.


9) Finishing Procedures Might lead to heat generation.

Cervical finishing might lead

to scratch or cementum loss.

Over carving leads to

exposure of dentin

10) Barodontology Expansion of air voids under or within a

restoration or gases in a non-vital teeth in

aeroplane.

Voids may be due to: inadequate

condensation.


11) Gingival reaction: Retraction cord and chemical

tissue packs.

Improperly contoured or

overhanging temporary

dressing.

Overcontoured permanent

restorations.

Undercontoured restorations

will contribute to mechanical

trauma of the free gingiva.

Excess cementing media.


12) Pulpal reaction:

Pulp exposure followed by a direct pulp capping might initiate hyperemia which can lead to RCT.

If hypersensitivity remains for several weeks the root canal treatment is recommended.

A direct pulp capping is considered successful if the tooth is a symptomatic and gives a positive vitality test from 3-6 months later.


13) Local anesthesia: Sometimes soreness occurs at the site of

injection as a result of haematoma and or

infection. Beside discoloration, the area is

usually tender.



c) Mechanical

d) Thermal

e) Idiopathic


b) Restorative phase and rest.


Vital teeth bleaching

Bleaching might cause mild

tooth sensitivity to temperature

changes and local oral

mucosal irritation

Sensitivity depends mainly on

the peroxide concentration and

the patient threshold.

Peroxides pass throught E. &

D. to pulp causing reversible

pulpilits

Diagnosis

History

Clinical exam

Radiographic exam

Differential diagnosis

1- History

Describition of pain as: onset, duration, stimuli, spontaneity, intensity and factors that relief the pain

Subjective evaluation (symptoms):

* verbal rating scale, which is a 4 scale grading pain as slight, moderate, severe and agonizing

1- History

* Visual analogue scale is a line of 10cm in length the extremes of the line represent from no pain and till the most sever pain

* McGill word descriptors by answering a pre prepared questionnaire

2- Clinical examination

Mechanical stimulus: Prob, scaler

Chemical (osmotic) stimulus: Sodium chloride, sucrose,

glucose and calcium chloride

Electric stimulus: Electrical pulp tester

2- Clinical examination

Evaporative test: Air blast,

Thermal stimulus: Ethyl chloride, ice stick

It involves:

*percussion *probing *trans-illumination

*Magnification & others to detect the cause

of the problem.

3- Radiographic examination

*To examine the bone, root and surrounding structure to confirm the diagnosis to exclude any other causes.

4- Differential diagnosis:

Dentin hypersensitivity is diagnosed

by exclusion, so all the other factors

should be ruled out.

From the diagnosis we can point the

aetiological factor and treat the source

of the problem

MANAGEMENT

I) Natural dentin desensitization

II) Management of the etiological

factors

III) Home care

IV) In office treatment


It involves deposition of

minerals within tubules that

results in a thicker layer of

peritubular dentin, this

process eventually results in a

smaller tubule diameter, less

permeable and less able to

transmit stimuli.

A- Dentin sclerosis:


Secondary dentin

develops after the tooth

root is formed, it is

secreted slowly on the

floor and roof of the

pulp results in decrease

in the size of the pulp

chamber.

B- Secondary dentin:

D

P


C- Tertiary dentin:

D P

Tertiary dentin or the

reparative dentin is formed

after the exposed dentin

has been traumatized by a

stimulus, this natural

process decrease the

permeability of dentin.


D- Smear layer:

It plugs the dentinal

tubule orifices with

debris that consists of

dental shavings, tissue

debris, odontoblastic

processes and microbial

elements..

D

S


E- Calculus:

It provides a protective coating to cover dentin

from stimuli. Usually sensitivity occurs

immediately after removal of heavy calculus

which subside naturally within 2 weeks.

2- Management of etiological factors:

It is important to identify these factors so that

prevention can be included in the treatment plan

before starting the Active management of Dentin

hypersensitivity which usually involve a

combination of home care and in-office therapies

3- Home care

Desensitizing toothpastes / dentifrices.

Toothbrush and toothpaste application.

Mouthwashes and chewing gums.

Dietary Modifications.

Management of parafunctional habits.

Desensitizing

tooth pastes

It contains potassium nitrate, which calms the nerve endings inside the dentine, relieving the pain of sensitive teeth.

Sodium fluoride, which helps prevent tooth decay and protects against acid erosion

Toothbrush and

toothpaste application

Soft or ultrasoft manual toothbrush with soft end rounded bristles

Lowers the risk of gingival recession and abrasion of exposed cementum and dentin.

Toothbrush and

toothpaste application

With powered

toothbrush less

pressure is

required on the

teeth, they require

a light grasp to

remove plaque.

Mouthwashes and

chewing gums

Potassium nitrate

Sodium fluoride

Potassium citrate

Sodium fluoride

Reduce acidic food and drinks.

Avoiding brushing immediately after ingestion of acidic food.

Drinking milk or water after consuming an acidic diet.

Dietary

Modification

Management of

parafunctional habits

Parafunctional habits

can result in:

bruxism.

Teeth flexure.

Abfractions.

N.B.: Treating the cause

as malocclusion, occlusal

prematuraty or stress.

Fluoride: sodium fluoride

and stannous fluoride can

reduce dentin sensitivity.

Fluorides decrease the

permeability of dentin in

vitro, possibly by

precipitation of insoluble

calcium fluoride within the

tubules.

In office treatment

Uses electricity to enhance diffusion of ions into the tissues. Dental iontophoresis is used most often in conjunction with fluoride pastes

Ionto-phoresis

Potassium nitrate

• Potassium nitrates gels at 5%

and 10% are effective in

reducing dentin hypersensitivity.

• Potassium nitrate does not

reduce dentin permeability but

do reduce the nerve excitability.

Oxalates

Super Seal®, a water-based potassium oxalate desensitizer

D/SENSE® CRYSTAL, a one step, dual action desensitizer and cavity liner.

Oxalate products reduce dentin permeability

and occlude tubules.

Calcium phosphates

Calcium phosphates occlude dentinal tubules and

decrease dentin permeability.

NovaMin: is bioactive glass

It consists of 45% SiO2, 24.5% Na2O,

24.5% CaO and 6% P2O5

it delivers an ionic form of calcium,

phosphorus, silica, and sodium which are

necessary for bone and tooth mineralization

The ions form hydroxyapatite crystals, a

form of hard and strong mineral in teeth and

blocks the open dentin tubules

NovaMin

http://en.wikipedia.org/wiki/Bioactive_glass

http://en.wikipedia.org/wiki/Silicon_dioxide


http://en.wikipedia.org/wiki/Sodium_oxide



http://en.wikipedia.org/wiki/Calcium_Oxide

http://en.wikipedia.org/wiki/Phosphorus_pentoxide




http://en.wikipedia.org/wiki/Ion

http://en.wikipedia.org/wiki/Calcium

http://en.wikipedia.org/wiki/Phosphorus

http://en.wikipedia.org/wiki/Silica

http://en.wikipedia.org/wiki/Sodium

http://en.wikipedia.org/wiki/Hydroxyapatite

Casein Phosphopeptides

It is a water based topical cream, sugar free

with bioavailable calcium and phosphate.

It provides extra teeth

protection and neutralize

acids from acidogenic

bacteria and from other

external and internal

acid sources.

Adhesives and resins

Including varnishes, bonding agents and restorative materials.

To occlude tubules in hypersensitive dentin.

Lasers ND(YAG) laser, ER:YAG laser

and WaterLase all reduce Dentin

hypersensitivity.

The effectiveness of lasers for

treating dentine hypersensitivity

varies from 5 to 100 percent,

depending on the type of laser

and the treatment parameters.

Extensive treatment

Crown and bridge

Root canal treatment

Or even extraction

Teeth Hypersensitivity 1

TEETH HYPERSENSITIVITY

Introduction:

Teeth hypersensitivity is an exaggerated response to a sensory

stimulus that usually causes no response in normal healthy teeth. As a

source of chronic irritation, teeth hypersensitivity affects eating, drinking,

and breathing. Hypersensitive teeth are characterized by transient pain in

response to evaporative, tactile, thermal, electrical or chemo-osmotic

stimulation of exposed dentin in teeth where no other defects or

pathology exist.

Aetiology of teeth hypersensitivity


a) Bacterial


c) Mechanical

d) Thermal

e) Idiopathic


a) Factors related to cavity preparation

b) Factors related to restorative phase and restorations

c) Factors related to vital teeth bleaching.


a) Bacterial:

Dental caries produces different levels of teeth hypersensitivity that is

mainly related to

1- The depth of decay

2- Dentin conductance

3- Pain threshold of the patient himself.


1- The depth of decay:

A- Caries in enamel involve no or little hypersensitivity,

B- In dentin is characteristic to be short and sharp pain arising from

exposed dentin in response to stimuli,

C- Dull ache pain if pulpal changes occur which might represent an

irreversible pulpitis .

2- Dentin conductance :

Greater degree of sensitivity happens when dental caries passes the

DEJ. as caries penetrates further into the tooth, sensitivity lessens until

pulp becomes involved .

Deeper in dentin and near the pulp, the number of dentinal tubules is

higher, the bigger the diameter of the dentinal tubules, the shorter their

length, the higher the permeability of the dentinal fluids and

consequently the higher the degree of hypersensitivity.

b) Chemical-Osmotic:

Erosion is defined as the dissolution of teeth by acids which are not of

bacterial origin. When an acid or an osmotic agent like sugar adhere to

the margins of leaky restoration or exposed dentin that will affect the

flow of dentinal fluid and result in hypersensitivity. Erosion can be of

Extrinsic or Intrinsic origin .


Extrinsic erosion results of exposure to extrinsic food, fluid or agents,

such as citrus fruits, pickled food, fruit juice, carbonated drinks,

wines, ciders, vitamin C, some mouth rinses with low PH and

bleaching agents especially those delivered in a vacuum formed trays

for In home applications .

Intrinsic erosion may result from gastric reflux as in Hiatus hernia,

alcoholism, eating disorders like bulimia nervosa (60)

. In case of

intrinsic erosion the palatal aspect of the upper anterior teeth and the

occlusal and buccal surfaces of the lower posterior teeth are primarily

affected.

c) Mechanical

i) Attrition:

Is defined as wear of teeth at sites of direct contact between teeth.

Attrition is associated with occlusal function and can be aggravated by

habits or parafunctional activities which is known as bruxism .

ii) Bruxism:

The aetiology of bruxism is unknown but it could be associated with:

Sleep disorders as obstructive sleep apnea and Snoring.

Malocclusion

High consumption of alcohol and heavy smoking

Stress, digestive problems.

Disorders as Huntington and parkinson’s diseases

Drugs as: MDMA, cocaine

The bruxism results in hypersensitivity to heat and cold, fractured

teeth and fillings, musculofacial pain and headache, stiffness and pain

in the joints and earache.


iii) Abrasion:

It is defined as the wear of teeth caused by objects other than other

teeth such as tooth brush/toothpaste abrasion, scaling and root

planning and pipe smoking .

iv) Abfraction:

It is defined as the wear of teeth at the cervical portion as a result of

occlusal loading that leads to cuspal flexure, this in turn results in

compressive and tensile stresses at the cervical fulcrum area of the

teeth with the resultant weakness and gradual loss of the cervical

portion.

v) Gingival recession:

It may result from tooth brush abrasion, malocclusion, excessive

brushing and flossing. Gingival recession results in exposure of

cementum which less resistant to abrasion and acids than enamel, that

consequently will lead to exposure of dentin and hypersensitivity .

vi) Cracked tooth syndrome:

It is defined as incomplete fracture of the vital teeth, can be involved

in dentin only or extending to the pulp. Cracked tooth syndrome

resulted in Teeth hypersensitivity with biting relieved with releasing

the bite. It might involve severe spontaneous pain in case of pulp

involvement, also can happen in sound teeth especially upper

premolars, or most commonly in teeth that is restored with big

restoration or direct gold .

vii) Trauma

Can involve fracture of enamel only with little or no sensitivity,

enamel and dentin with moderate to sharp pain with stimuli typically

evaporative, thermal, mechanical (tactile) or osmotic, pulp

involvement with dull ache spontaneous pain, or fracture of the root

which will result in tenderness to touch or percussion. The trauma


might result in no damage at all but tenderness to touch as a result of

trauma to the periodontal ligament that can subside later.

d) Thermal and idiopathic:

Which can result in reversible hypersensitivity that subside by treating

the exposed dentin and preventing the cause, and irreversible pulpal

damage.


a) Factors related to cavity preparation:

i) Type of cutting instruments:

Rotary instruments produce more heat generation than the hand

instruments. Dull instruments might require higher pressure for cutting

which will result in more heat generation. Heat can destruct pulpal

tissue, coagulate protoplasm and even burn dentin. Proper cooling is

mandatory with all rotary instruments.

ii) Instrumentation pressure:

Cause heat generation and might cause actual aspiration of

odontoblastic nuclei into the tubules.

iii) Vibration:

Cause a rebound response as a result of using eccentric burs, which

can result in necrotizing effects on dentin. Rebound response appears

microscopically as a limited area of necrosis at an area remote from

the cut dentinal tubules.

iv) Dentin Desiccation:

Can result from heating of dentin during cutting, use of chemicals to

sterile the cavity or use of air as a coolant for final cavity toilet.

v) Actual cutting in dentin:

Every square millimetre of dentin cut exposes 30,000 to 45,000

dentinal tubules with resultant fluid movement in each one of them

stimulating nerve damage.


b) Factors related to restorative phase and restorations

i) Polymerization shrinkage

The polymerization shrinkage results in stresses at the

composite/tooth interface resulting in microleakage, micro cracks

or deformation of tooth structure. Microleakage can result in

secondary caries formation and the consequent teeth

hypersensitivity. Stresses are greatest in cavities with high ratio of

C factor (ratio of bonded surfaces to unbonded surfaces),

decreasing C factor will result in decreasing stresses from

polymerization shrinkage.

ii) Undercured resin

Can result from a light source of inadequate intensity, or not close

enough to the resin, or a light which is attenuated by passage

through tooth structure or restoration. That results in a well cured

surface covering incompletely cured layer, which will result in

marginal fracture, open margin and chemical toxicity from the

monomers or the bonding agent.

iii) Microleakage

Any restoration though exhibits clinical satisfactory adaptation,

shows some leakage. The ingress of fluids and micro organisms

can be the cause of dentinal hypersensitivity in addition to the fluid

movements within the dentinal tubules.

iv) Inadequate liner and/or base

Any metallic restoration conducts thermal changes to the underlying dentin

and pulp which can cause hypersensitivity specially in the first few days

postoperatively. The pain is elicited after heat or cold application and


relieved with removal of the stimulus. The greater the temperature

gradient,the more painful and lasting the stimulus. The dentin

effectiveness as a thermal insulator depends on its thickness.

v) Fractured restoration

Exposes dentin, admits oral fluids and microbes which will cause

recurrent caries and dentin hypersensitivity.

vi) Cracked tooth

Pain on biting and eating citrus fruits, this sharp pain will disappear

when pressure is released. Commonly happens in teeth with large

restoration and cast restoration without proper consideration for cusp

protection .

vii) Galvanism

When two dissimilar metallic restorations brought into contact the

current will pass between them and a galvanic stimuli will be generated.

Hypersensitivity is usually felt in the tooth containing the restorative

with the lower potential, i.e: Amalgam .

The degree of hypersensitivity will depend on some factors as:

The difference in the electrical potential between the dissimilar metals,

the electrical resistance of dentin and soft tissues, presence of base and

its thickness, the current intensity, the pulpal condition and the patient

threshold.

viii) Faulty occlusal and/or proximal relationship

Occlusal contact if high will affect the periodontal ligament and lead to

sensitivity with bite and/ or mobility.

Proximal contact if tight will result in excessice pressure that might

result in pain and interproximal bone resorption and damage of the

supporting structure.


Proximal contact if light will result in food impaction interproximally and

gingival inflammation, which if neglected will result in damage of the

supporting structure.

ix) Finishing Procedures

Over finishing of restoration might result in heat generation which will

lead to hypersensitivity.

Finishing of the restoration cervically might lead to scratch or total loss

of the cemetum in this area.

Over carving of Amalgam restoration or uncovering the exposed dentin

by cement in case of indirect restoration will result in teeth

hypersensitivity.

x) Barodontology

It is the teeth hypersensitivity that occurs with reduced pressure, which

occur during Aviation (in aeroplane). This could be due to expansion of

air voids under a restoration, gases in a non-vital or due to expansion of

air voids incorporated into the restoration during its application. Voids

may be due to: inadequate condensation.

xi) Gingival reaction to the restorative procedure and restoration

Retraction cord and chemical tissue packs used before the elastic

impression taking, can result in soft tissue irritation.

Improperly contoured or overhanging temporary dressing can

result in gingival irritation.

Overcontoured permanent restorations will contribute to poor

gingival health by preventing through cleaning of the area.

Undercontoured restorations will contribute to lack of protection of

the gingival crevice and mechanical trauma of the free gingiva.


Cementing media left in the crevice may cause gingival irritation

that ranges from mild to severe inflammation..

xii) Pulpal reaction to the restorative procedure and restoration.

The pulpal reaction to a restorative procedure is difficult to determine,

sometimes even with a conservative cavity preparation, the pulp

experiences a degree of degeneration. Deep restoration may cause the

pulp to devitalize many years later.

A pulp exposure followed by a direct pulp capping might initiate an

immediate hyperemia which can lead to root canal treatment.

Generally if the hypersensitivity remains for several weeks the root

canal treatment is recommended. A direct pulp capping is considered

successful if the tooth is a symptomatic and gives a positive vitality

test from 3-6 months later.

xiii) Local anesthesia

Sometimes soreness occurs at the site of injection as a result of

haematoma and or infection. Beside discoloration the area is usually

tender.

c) Factors related to vital teeth bleaching.

Both office and home bleaching procedures may induce discomfort in

some patients. The principal complaints are mild tooth sensitivity to

temperature changes and local oral mucosal irritation.

Bleaching sensitivity is commonly associated with Carbamide peroxide

vital teeth bleaching (32)

due to the by products of 10% carbamide

peroxide readily pass through the enamel and dentin into the pulp in a

matter of minutes. Sensitivity takes the form of reversible pulpitis caused

from the dentin fluid flow and pulpal contact of the material. Sensitivity


can happen in any form of the bleaching agents, it depends mainly on the

peroxide concentration and the patient threshold.

Natural dentin desensitization (22)

Some natural processes can improve hypersensitivity overtime, even

without treatment intervention. These include sclerosis of dentin,

deposition of secondary and tertiary dentin, creation of a smear layer and

calculus formation on the surface of the dentin.

Sclerosis of dentin involves deposition of minerals within tubules that

results in a thicker layer of peritubular dentin, this process eventually

results in the tubule becoming smaller in diameter, making it less

permeable and less able to transmit stimuli.

Secondary dentin develops after the tooth root is formed, it is secreted

slowly on the floor and roof of the pulp results in decrease in the size of the

pulp chamber.

Tertiary dentin or the reparative dentin is formed after the exposed dentin

has been traumatized by a stimulus, this natural process decrease the

permeability of dentin.


The smear layer is described as a combination of organic and inorganic

debris, the smear layer plugs the dentinal tubule orifices with debris that

consists of dental shavings, tissue debris, odontoblastic processes and

microbial elements.

Calculus formation provides a protective coating to cover dentin from stimuli.

Usually sensitivity ocurrs immediately after removal of heavy calculus which

subside naturally within 2 weeks.

Management of postoperative dentin Hypersensitivity

Diagnosis:Which includes:

History taking, clinical examination and differential diagnosis, assessment of

the etiological factors and management of the etiological factor after

accurate diagnosis

a) History:

The patient is asked to describe the characteristics of pain as: onset, duration,

stimuli, spontaneity, intensity and factors that relief the pain.

After careful listening to the pt, the dentist need to gather the information

related to Subjective information (symptoms) and the objective information

(Signs) through clinical examination.

Subjective evaluation could be carried out by a verbal rating scale, which is

a 4 scale grading pain as slight, moderate, severe and agonizing, by Visual

analogue scale is a line of 10cm in length the extremes of the line represent

the limits of pain experienced by the patient from no pain and till the most

sever pain and the McGill word descriptors by answering a pre prepared

questionnaire.

b) Clinical and Radiographic examination:

it is the objective evaluation of clinical signs using:)


- Mechanical stimulus: Probe, scaler, constant pressure probe and Yeaple

pressure stimulators.

- Chemical (osmotic) stimulus: Sodium chloride, sucrose, glucose and

calcium chloride.

- Electric stimulus: Electrical pulp tester and dental pulp stethoscope.

- Evaporative test: air blast, Air jet stimulator

- Thermal stimulus: Ethyl chloride, ice stick and heat thermoelectric

devices.

It involves clinical examination of teeth by percussion, probing, trans-

illumination and other methods to detect the cause of the problem as

caries, fractured restoration, cracked tooth or others.

c) Radiographic examination to examine the bone, root and surrounding

structure to confirm the diagnosis.

d) Differential diagnosis:

Dentin hypersensitivity is diagnosed by exclusion (33)

, so all the other

factors should be ruled out. From the diagnosis we can point the

aetiological factor and treat the source of the problem.

Techniques to Reduce Preoperative Hypersensitivity

Minimize preparation trauma

Maximize dentin seal using dentin bonding agents

Avoid :

– inadequate isolation

– overetching, dessicating demineralized dentin

– inadequate priming, primer solvent not evaporated

– inadequate adhesive placement, adhesive not photopolymerized

Ensure temporary crown is well-fitting

Ensure correct occlusal contacts


Techniques to Reduce Preoperative Hypersensitivity

I) Home care:

Desensitizing toothpastes / dentifrices

Potassium salts

Toothbrush and toothpaste application: Practitioners should educate

patients on how to use dentifrices and monitor their toothbrushing

techniques. Use of a soft or ultrasoft manual toothbrush with soft end

rounded bristles lowers the risk of gingival recession and abrasion of

exposed cementum and dentin. With powered toothbrush less pressure is

required on the teeth, they require a light grasp to remove plaque.

Dentifrices should be applied by toothbrushing. There is no evidence to

suggest that finger application of the paste increases effectiveness. Many

patients habitually rinse their mouths with water after toothbrushing.

Rinsing with water may cause the active agent to be diluted and cleared

from the mouth and, thus, reduce the efficacy of the caries-reducing

effect of fluoride toothpastes.

Mouthwashes and chewing gums: Studies have found that mouthwashes

containing potassium nitrate and sodium fluoride, potassium citrate or

sodium fluoride or a mixture of fluorides) can reduce Dentine

hypersensitivity.

Dietary Modifications: Controlling the consumption of acidic food and

drinks such as citrus fruits, wine, pickled foods and carbonated

beverages. Avoiding brushing immediately after ingestion of acidic food,

as it may accelerate the combined effect of abrasion and erosion, rinsing

with water is recommended before brushing. Additional

recommendations includes drinking something neutral or alkaline such as

milk or water after consuming an acidic diet, Sipping acidic drinks

through a straw and reducing the quality and frequency of acid intake.


Management of parafunctional habits:

Parafunctional habits can result in bruxism, teeth flexure or abfractions

that lead to hypersensitivity, treating the cause as malocclusion, occlusal

prematuraty or stress is recommended first, then preventing further tooth

structure damage by conservative measures as night guard and fluoride.

If home care fails to reduce Dentine hypersensitivity compared with

baseline levels, the next level of treatment, an in-office method, should be

started.

ii) In office treatment:

Fluoride: Fluorides such as sodium fluoride and stannous fluoride can

reduce dentin sensitivity.) Fluorides decrease the permeability of dentin in

vitro,) possibly by precipitation of insoluble calcium fluoride within the

tubules.

Ionto-phoresis: This procedure uses electricity to enhance diffusion of

ions into the tissues. Dental iontophoresis is used most often in

conjunction with fluoride pastes or solutions ) and reportedly reduces

Dentin hypersensitivity.

Potassium nitrate: Potassium nitrate, which usually is applied via a

desensitizing toothpaste, also can reduce dentin sensitivity when applied

topically in an aqueous solution or an adhesive gel. Potassium ions do

reduce nerve excitability in animal models.

Oxalates: Oxalate products reduce dentin permeability and occlude

tubules more consistently in laboratory studies than they do in clinical

trials.

Calcium phosphates: Calcium phosphates may reduce dentin sensitivity

effectively. Calcium phosphates occlude dentinal tubules and decrease

dentin permeability.


Orajel Tooth Desensitizer : treats pain from sensitive teeth by blocking

dentinal tubules preventing excitation of the tooth nerve.

NovaMin: is the brand name of a particulate bioactive glass that is used

in dental care products. It consists of 45% SiO2, 24.5% Na2O, 24.5%

CaO and 6% P2O5. it delivers an ionic form of calcium, phosphorus,

silica, and sodium which are necessary for bone and tooth mineralization.

NovaMin can be used an effective, non-toxic alternative to fluoride.

Casein Phosphopeptides: It is a water based topical cream, sugar free

with bioavailable calcium and phosphate, in the form of CPP-ACP

(casein phosphopeptides- amorphous calcium phosphates. Recent studies

reported that it provides extra teeth protection and neutralize acids from

acidogenic bacteria and from other external and internal acid sources.

Adhesives and resins: Because many topical desensitizing agents do not

adhere to the dentin surface, their effects are temporary. Stronger and

more adhesive materials offer improved and longer-lasting

desensitization. In the 1970s,

Lasers:The effectiveness of lasers for treating dentine hypersensitivity

varies from 5 to 100 percent, depending on the type of laser and the

treatment parameters.

http://en.wikipedia.org/wiki/Bioactive_glass



http://en.wikipedia.org/wiki/Calcium_Oxide


http://en.wikipedia.org/wiki/Ion

http://en.wikipedia.org/wiki/Calcium

http://en.wikipedia.org/wiki/Phosphorus

http://en.wikipedia.org/wiki/Silica

http://en.wikipedia.org/wiki/Sodium

http://en.wikipedia.org/wiki/Fluoride

Documents

TEETH HYPERSENSITIVITY · hypersensitivity remains for several weeks the root canal treatment is recommended. A direct pulp capping is considered successful if the tooth is a symptomatic