Preventive Procedures - Outcome 7

Question 1

Dentinal Hypersensitivity Defintion

Answer 1

dentinal hypersensitivity is transient pain that occurs from exposed dentin, typically triggered by stimuli such as cold or touch. This pain cannot be attributed to any other dental defect or pathology and usually subsides quickly once the stimulus is removed

Question 2

Conditions Required for Hypersensitivity

Answer 2

2 key factors are necessary for dentinal hypersensitivity:

1. exposed dentin - dentin must be exposed for hyper sensitivy to occur
2. open dentinal tubules - these tubules allow stimuli to reach the nerve endings within the dentin

Question 3

Visually identifying exposed dentin

Answer 3

it can be challenging to visually identify exosed dentin, so patient-reported symptoms should not be disregarded. However, not all exposed dentin is necessarily sensitive, as some dentinal tubules may be blocked microscopically, preventing stimuli fro reaching the nerve

Question 4

Dentinal hypersensitivity most commonly affects…

Answer 4

the facial surfaces of teeth near the cervial third, especially canines, premolars and molars

Question 5

Predisposing Factors

Answer 5

The most frequent cause of exposed dentinal tubules is gingival recession. Other factors contributing to gingal recession include..

-Chronic bacterial plaque
-Toothbrush abrasion
-Gingival laceration from oral habits like toothpick use
-Excessive flossing
-Crown preparation
-Inadequate attached gingiva
-Gingival loss due to disease or surgery

Additionally, loss of enamel and cementum can also expose dentin and lead to hypersensitivity.

Question 6

Assessing Hypersensitivity

Answer 6

Accurate diagnosis is crucial for effective management of dentinal hypersensitivity. It can resemble other conditions such as dental caries, fractured enamel/dentin, reversible pulpitis, or post-whitening sensitivity

Diagnosis involves a thorough clinical history and examination by a dentist or dental hygienist. Other potential causes of dental pain must be ruled out before confirming dentinal hypersensitivity.

Question 7

Techniques to aid in diagnosis may include..

Answer 7

1. Using an explorer along areas of exposed dentin and the cement-enamel junction
2. Applying a cold solution or air to suspect areas
3. Observing pain response to tapping teeth (to indicate pulpitis/peridontal involvement) or pain on biting (suggestive of fracture)

Question 8

Stimuli can be classified into five main types: thermal, mechanical, chemical, evaporative, and osmotic

Answer 8

1. Thermal
2. Mechanical
3. Chemical
4. Evaporative
5. Osmotic

Question 9

Thermal Stimuli

Answer 9

Includes hot or cold foods and beverages, cold air entering the mouth, and rapid drying of a tooth surface, which lowers tooth temperature

Question 10

Mechanical Stimuli

Answer 10

Involves toothbrush bristles, metal utensils, dental hygiene tools, friction from denture clasps, or other removable prosthetic or orthodontic appliances

Question 11

Chemical Stimuli

Answer 11

Consists of acidic or sugary foods (like citrus fruits, sweet, sour, or highly acidic foods), bacterial plaque by-products, and some topical agents or sweeteners in toothpaste. Individuals with bulimia may experience hypersensitivity due to repeated exposure to highly acidic gastric juices

Question 12

Evaporative Stimuli

Answer 12

Refers to the dehydration of oral fluids caused by a short blast of air or high-volume suction

Question 13

Osmotic Stimuli

Answer 13

Involves changes in osmotic pressure within the dentinal tubules due to isotonic solutions like sugar and salt

Question 14

Not all stimuli will cause pain in every individual. This variation occurs because each person has unique sensitivities to different stimuli. Consequently:

Answer 14

-A desensitizing product may work for one person but not another.
-A product might be effective for one tooth but not for others in the same mouth.
-Some treatments may address specific types of stimuli but not others.

Question 15

How Dentin Responds to Stimuli

Answer 15

Dentin is a highly sensitive tissue that differs from other body tissues in how it perceives stimuli. Unlike the skin, which can detect cold, heat, touch, and pain separately, dentin and pulp perceive all stimuli as pain. This is because the pulp contains only free pain receptor nerve endings, making it difficult to pinpoint the exact area of sensitivity.

Question 16

Dentin Anatomy

Answer 16

Dentin is protected by hard tissues like enamel or cementum. The dentin itself is a vital tissue with dentinal tubules, which contribute to its sensitivity. These tubules are filled with odontoblastic processes that extend from the pulp to the dentino-enamel junction Odontoblasts, the primary cells in the pulp, have extensions known as odontoblastic processes that are surrounded by dentinal fluid within the tubules

Question 17

3 Theories of Tooth Surface Hypersensitvity

Answer 17

Three major theories have been proposed to explain dentinal sensitivity:

1. Direct Innervation Theory
2. Odontoblast Receptor Theory
3. Hydrodynamic Theory

The Hydrodynamic Theory is the most widely accepted and will be discussed in detail below.

Question 18

Hydrodynamic Theory

Answer 18

Brännstrom (1964) proposed that dentinal pain arises from a hydrodynamic mechanism, or “fluid force.”

According to this theory, when a stimulus is applied to the opening of exposed dentinal tubules, it causes the movement of tubular fluid within the tubules. This fluid movement stimulates nerve fibers

The tubules are narrow and contain most of the fluid in dentin. Nerve fibers from the pulp extend into these tubules. The movement of fluid creates pressure changes that affect the underlying pulp, stimulating sensory nerve endings and resulting in pain.

In essence, pressure changes excite sensory nerve endings near the pulp within the tubules, which are interpreted as pain

Dentinal hypersensitivity depends on the presence of open dentinal tubules and viable pulpal innervation.

Question 19

Natural defence mechanisms that gradually alleviate sensitivity

Answer 19

1. Sclerosis of Dentin
2. Secondary Dentin
3. Smear Layer
4. Calculus

Question 20

Oral hygiene care and desensitizing agents address dentinal hypersensitivity in two main ways:

Answer 20

1. Preventing Nerve Depolarization: This interrupts neural transmission to the pulp
2. Occluding Tubule Openings: By blocking the ends of dentinal tubules or reducing their diameter, the movement of tubule fluid is minimized

Question 21

Treatment Goals of Desensitizing Agents:

Answer 21

1. Relief of Pain
2. Modification or Elimination of Contributing Factors

Question 22

Self Care Measures VS. Professional Interventions - for Sensitivity

Answer 22

Combining self-care measures with professional interventions usually yields the best results for managing hypersensitivity`

Question 23

Fluoride as a Desensitizing Agent

Answer 23

Research shows that fluoride toothpaste and concentrated fluoride solutions are effective in managing dentinal hypersensitivity. This efficacy is attributed to fluoride’s ability to enhance dentin’s resistance to acid decay and form calcium fluoride crystals within the exposed dentinal tubules

Question 24

Dentinal Hypersensitivity summary

Answer 24

Sensitivity from exposed dentin is common among adults. Open dentinal tubules allow stimuli in the mouth to reach the pulp through nerve fibers within the tubules. Desensitizing products work by either blocking these open tubules or by reducing the nerve fibers’ responsiveness to stimuli.

Effective plaque control is essential for managing slight to moderate sensitivity. This includes proper brushing techniques, using low-abrasive desensitizing toothpastes, and reducing acidic foods and beverages in the diet. For severe sensitivity, professional treatment is often necessary.

Question 25

Conditions That May Modify or Contraindicate the Use of Desensitizing Agents:

Answer 25

1. Patient Allergies: Review the patient’s medical history for any reported allergies.
2. Oral Lesions: Examine the oral cavity for any lesions or ulcerated areas where desensitization is planned.
3. Dental Diseases: Avoid desensitizing agents if the sensitivity is caused by pulpitis or other dental conditions.