Dentine Hypersensitivity

Dentine Hypersensitivity

• Dentine hypersensitivity is a painful response to stimuli, characterized by short, sharp pain, rapid onset, and quick resolution, in the absence of other symptoms.
• This pain is triggered by exposed dentine, a tooth's inner layer, in response to stimuli like temperature changes (hot/cold), chemicals (acid, whitening agents), or mechanical pressure (brushing, chewing).
• The pain mechanism involves stimuli activating the nerve endings in the pulp through exposed dentinal tubules.

GDC Learning Outcomes for Oral and Dental Science

• Understanding oral diseases including their aetiology (causes) and pathogenesis (development) is crucial for preventative and treatment strategies.
• Comprehensive and contemporaneous patient histories are essential for accurate diagnosis.
• Recognizing changes in patient's oral health status and addressing them appropriately are key aspects of effective care.
• Roles and responsibilities of dental therapists and other dental team members within the treatment plan should be understood.

Pre-reading for Histology of Enamel and Dentine

• This area of study focuses on the microscopic structure of enamel and dentine, which are crucial to understanding tooth structure and function.

Learning Objectives for Dentine Hypersensitivity

• Understand the typical presentation of dentine hypersensitivity.
• Identify and describe the factors that contribute to its development.
• Recognize the role of the dental professional in patient management and advice, including preventive treatments.
• Understand the mechanism of dentine hypersensitivity.

What is Dentine Hypersensitivity?

• Dentine hypersensitivity is the response to external stimuli by exposed dentine.
• It's characterized by an overreaction, having too much sensitivity to normally non-painful stimuli.

Tooth Anatomy and Dentine Hypersensitivity

• The structure of a tooth is relevant in understanding dentine hypersensitivity.
• Anatomically, exposed dentinal tubules with no enamel protection are crucial in the development of pain.

How Pain is Registered - Theories

• A,B, and C pain theories describe how the nerves respond to pain stimuli.
  • Theory A directly involves pain sensation.
  • Theory B describes how the exposed tooth surface can transmit the pain from the dentinal tubules.
  • Theory C describes the movement of fluid within the dentinal tubules as a cause of pain.

Hydrodynamic Theory

• The hydrodynamic theory proposes that fluid flow within dentinal tubules in response to stimuli carries signalling molecules to the nerve endings, inducing pain.
• This theory has implications for understanding pain mechanisms in dentine hypersensitivity.

Osmosis in Dentine Hypersensitivity

• Osmosis plays a role in dentine hypersensitivity by transporting fluid between areas of differing concentration.
• Understanding osmosis within the dentinal tubules helps to understand the fluid movement and pain perception in exposed parts of the tooth.

Stimuli for Dentine Hypersensitivity

• Thermal stimuli (temperature changes, hot or cold)
• Chemical stimuli (acids in foods, whitening gels)
• Mechanical stimuli (tooth brushing, chewing, eating)

Aetiology of Dentine Hypersensitivity

• Exposed dentine is the primary cause of the painful response.

Causes of Exposed Dentine (and therefore dentine hypersensitivity)

• Receding gums
• Tooth brushing habits/abrasion
• Periodontal disease
• High frenum
• Eating habits
• Nail biting
• Dental treatments (filling work, root canal procedures)
• Orthodontic treatment
• Opening items (e.g. jewellery)
• Piercings

Clinical Examination for Dentine Hypersensitivity

• Carefully asses the morphology of teeth to identify areas at risk (exposed).
• Identify the source of the pain in the suspected area.
• Applying pain stimuli to affected areas (3 in 1 trigger).

Diagnosis of Dentine Hypersensitivity

• Based on patient history (symptoms, triggers) and clinical examination.

Dental Hygiene and Therapists Role

• Identify if the pain is from hypersensitivity.
• Determine potential causes; diet history, oral health, etc.
• Educate patients on the issue and its management.
• Provide preventative care and advice.

Patient Management of Dentine Hypersensitivity

• Provide patients with recommendations for at-home care and management, such as using specific dental products (e.g., toothpastes, mouthwashes).

Mechanisms of Action for Dentine Desensitizing Agents

• Removal of the stimulus causing hypersensitive response
• Desensitize the nerves
• Occlude the tubules to prevent damage
• Prevent tubules from exposing to the stimulus

How Agents Work

• Calcium Phosphosilicate
• Calcium triphosphate
• Bioactive glass
• Strontium Chloride/Acetate
• Fluoride

Occluding Dentinal Tubules

• Agents that create a barrier within the tubules and reduce fluid flow, decreasing the pain response are effective in sealing off the exposed areas.

Challenge and Solutions

• Chemical ions dissolving away readily.
• Implementing solutions that cause the chemicals to stick the tooth surface:
  • Using proteins
  • Applying chemicals which precipitate in acidic environments.
  • Higher concentration of fluoride use
  • Daily use for long-term effects
  • Spitting (holding chemicals on the tooth surface).

Agents for Use at Home

• Colgate (arginine)
• Sensodyne (stannous fluoride)
• Fluoride

Potassium Nitrate in Dentine Hypersensitivity

• Maintaining a potassium concentration equilibrium in the oral environment is essential for reducing pain responses.

Professional Treatment

• Specific dental materials/products, procedures
• Desensitizing agents
• Treatment of the underlying cause

Summary

• Identify the pain
• Identify the cause (aetiology)
• Educate the patient
• Refer to a GDP if needed
• Provide advice on self-care

Recommended Reading

• Review of terminology, epidemiology, and management of conditions related to Dentine Hypersensitivity
• Current guidelines in General Dental Practice for the management of hypersensitivity.