Salivary Factors and Their Mechanisms

1. Buffering Factors

Buffering factors in saliva help maintain a neutral pH in the oral cavity, which is vital for preventing demineralization of tooth enamel.

• HCO3 (Bicarbonate)

  • Effects on Mineralization: Acts as a primary buffer in saliva, helping to neutralize acids produced by bacteria.
  • Role in Raising Saliva or Plaque pH: Increases pH by neutralizing acids, thus promoting a more favorable environment for remineralization.

• Urea

  • Effects on Mineralization: Releases ammonia (NH3) when metabolized, which can help raise pH and promote mineralization.
  • Role in Raising Saliva or Plaque pH: Contributes to pH elevation through ammonia production.

• Arginine-rich Proteins

  • Effects on Mineralization: Releases ammonia, which can help neutralize acids and promote remineralization.
  • Role in Raising Saliva or Plaque pH: Increases pH through ammonia release, creating a less acidic environment.

2. Antibacterial Factors

Saliva contains several antibacterial components that help control the growth of pathogenic bacteria associated with dental caries.

• Lactoferrin

  • Effects on Bacteria: Binds to iron, which is essential for bacterial growth, thereby inhibiting bacterial proliferation.
  • Effects on Bacterial Aggregation or Adherence: May promote clearance of bacteria through aggregation.

• Lysozyme

  • Effects on Bacteria: Hydrolyzes cell wall polysaccharides of bacteria, leading to cell lysis and death.
  • Effects on Bacterial Aggregation or Adherence: Can indirectly promote clearance by breaking down bacterial cell walls.

• Peroxidase

  • Effects on Bacteria: Produces hypothiocyanate (OSCN), which inhibits glycolysis in bacteria, reducing their energy supply.
  • Effects on Bacterial Aggregation or Adherence: May help in the aggregation of bacteria, facilitating their clearance.

• Secretory IgA

  • Effects on Bacteria: Neutralizes bacterial toxins and enzymes, reducing their pathogenicity.
  • Effects on Bacterial Aggregation or Adherence: Binds to bacterial surfaces, preventing adherence to oral tissues.

• Alpha Amylase

  • Effects on Bacteria: Produces glucose and maltose, which can serve as energy sources for some bacteria.
  • Effects on Bacterial Aggregation or Adherence: Indirectly promotes bacterial aggregation through the production of glucans.

3. Factors Affecting Mineralization

Certain salivary proteins play a role in the mineralization process and the maintenance of tooth enamel.

• Histatins

  • Effects on Mineralization: Bind to hydroxyapatite, aiding in the supersaturation of saliva, which is essential for remineralization.
  • Effects on Bacteria: Some inhibition of mutans streptococci, which are key contributors to caries.

• Proline-rich Proteins

  • Effects on Mineralization: Bind to hydroxyapatite, aiding in saliva supersaturation.
  • Effects on Bacteria: Promote adherence of some oral bacteria.

• Cystatins

  • Effects on Mineralization: Bind to hydroxyapatite, aiding in saliva supersaturation.
  • Effects on Bacteria: Promote adherence of some oral bacteria.

• Statherin

  • Effects on Mineralization: Bind to hydroxyapatite, aiding in saliva supersaturation.
  • Effects on Bacteria: Promote adherence of some oral bacteria.

• Mucins

  • Effects on Mineralization: Provide a physical and chemical barrier in the enamel pellicle, protecting against demineralization.
  • Effects on Bacteria: Facilitate aggregation and clearance of oral bacteria.

Growth Theories

Understanding the growth of craniofacial structures is crucial in pedodontics, as it directly influences dental development, occlusion, and treatment planning. Various growth theories have been proposed to explain the mechanisms behind craniofacial growth, each with its own assumptions and clinical implications.

Growth Theories Overview

1. Genetic Theory (Brodle, 1941)

• Assumption: Genes control all aspects of growth.
• Application: While genetic factors play a role, external factors significantly modify growth, reducing the sole impact of genetics. Inheritance is polygenic, influencing predispositions such as Class III malocclusion.

2. Scott’s Hypothesis (1953)

• Assumption: Cartilage has innate growth potential, which is later replaced by bone.
• Application:
  • Mandibular growth is likened to long bone growth, with the condyles acting as diaphysis.
  • Recent studies suggest that condylar growth is primarily reactive rather than innate.
  • Maxillary growth is attributed to the translation of the nasomaxillary complex.

3. Sutural Dominance Theory (Sicher, 1955)

• Assumption: Sutural connective tissue proliferation leads to appositional growth.
• Application:
  • Maxillary growth is explained by pressure from sutural growth.
  • Limitations include inability to explain:
    • Lack of growth in suture transplantation.
    • Growth in cleft palate cases.
    • Sutural responses to external influences.

4. Moss’s Functional Theory (1962)

• Assumption: Functional matrices (capsular and periosteal) control craniofacial growth, with bone responding passively.
• Application:
  • Examples include excessive cranial vault growth in hydrocephalus cases, illustrating the influence of functional matrices on bone growth.

5. Van Limborgh’s Theory (1970)

• Assumption: Skeletal morphogenesis is influenced by:
  1. Intrinsic genetic factors
  2. Local epigenetic factors
  3. General epigenetic factors
  4. Local environmental factors
  5. General environmental factors
• Application:
  • Highlights the interaction between genetic and environmental factors, emphasizing that muscle and soft tissue growth also has a genetic component.
  • Predicting facial dimensions based on parental studies is limited due to the polygenic and multifactorial nature of growth.

6. Petrovic’s Hypothesis (1974, Cybernetics)

• Assumption: Primary cartilage growth is influenced by differentiation of chondroblasts, while secondary cartilage has both direct and indirect effects on growth.
• Application:
  • Explains the action of functional appliances on the condyle.
  • The upper arch serves as a mold for the lower arch, facilitating optimal occlusion.

7. Neurotropism (Behrents, 1976)

• Assumption: Nerve impulses, through axoplasmic transport, have direct growth potential and influence soft tissue growth indirectly.
• Application:
  • The effect of neurotropism on growth is reported to be negligible, suggesting limited clinical implications.

Clinical Implications

Understanding these growth theories is essential for pediatric dentists in several ways:

• Diagnosis and Treatment Planning: Knowledge of growth patterns aids in diagnosing malocclusions and planning orthodontic interventions.
• Timing of Interventions: Recognizing the stages of growth can help in timing treatments such as extractions, space maintainers, and orthodontic appliances.
• Predicting Growth Outcomes: Awareness of genetic and environmental influences can assist in predicting treatment outcomes and managing patient expectations.

Polycarbonate Crowns in Pedodontics

Polycarbonate crowns are commonly used in pediatric dentistry, particularly for managing anterior teeth affected by nursing bottle caries. These crowns serve as temporary fixed prostheses for primary teeth, providing a functional and aesthetic solution until the natural teeth exfoliate. This lecture will discuss the indications, contraindications, and advantages of polycarbonate crowns in pedodontic practice.

Nursing Bottle Caries

• Definition: Nursing bottle caries, also known as early childhood caries, is a condition characterized by the rapid demineralization of the anterior teeth, primarily affecting the labial surfaces.
• Progression: The lesions begin on the labial face of the anterior teeth and can lead to extensive demineralization, affecting the entire surface of the teeth.
• Management Goal: The primary objective is to stabilize the lesions without attempting a complete reconstruction of the coronal anatomy.

Treatment Approach

1. Preparation of the Lesion:

   • The first step involves creating a clean periphery around the carious lesion using a small round bur.
   • Care should be taken to leave the central portion of the affected dentin intact to avoid pulp exposure.
   • This preparation allows for effective ion exchange with glass ionomer materials, facilitating a good seal.

2. Use of Polycarbonate Crowns:

   • Polycarbonate crowns are indicated as temporary crowns for deciduous anterior teeth that will eventually exfoliate.
   • They provide a protective covering for the tooth while maintaining aesthetics and function.

Contraindications for Polycarbonate Crowns

Polycarbonate crowns may not be suitable in certain situations, including:

• Severe Bruxism: Excessive grinding can lead to premature failure of the crown.
• Deep Bite: A deep bite may cause undue stress on the crown, leading to potential fracture or dislodgment.
• Excessive Abrasion: High levels of wear can compromise the integrity of the crown.

Advantages of Polycarbonate Crowns

Polycarbonate crowns offer several benefits in pediatric dentistry:

• Time-Saving: The application of polycarbonate crowns is relatively quick, making them efficient for both the clinician and the patient.
• Ease of Trimming: These crowns can be easily trimmed to achieve the desired fit and contour.
• Adjustability: They can be adjusted with pliers, allowing for modifications to ensure proper seating and comfort for the patient.

Hypnosis in Pediatric Dentistry

Hypnosis: An altered state of consciousness characterized by heightened suggestibility, focused attention, and increased responsiveness to suggestions. It is often used to facilitate behavioral and physiological changes that are beneficial for therapeutic purposes.

• Use in Pediatrics: According to Romanson (1981), hypnosis is recognized as one of the most effective nonpharmacologic therapies for children, particularly in managing anxiety and enhancing cooperation during medical and dental procedures.
• Dental Application: In the field of dentistry, hypnosis is referred to as "hypnodontics" (Richardson, 1980) and is also known as psychosomatic therapy or suggestion therapy.

Benefits of Hypnosis in Dentistry

1. Anxiety Reduction:

   • Hypnosis can significantly alleviate anxiety in children, making dental visits less stressful. This is particularly important for children who may have dental phobias or anxiety about procedures.

2. Pain Management:

   • One of the primary advantages of hypnosis is its ability to reduce the perception of pain. By using focused attention and positive suggestions, dental professionals can help minimize discomfort during procedures.

3. Behavioral Modification:

   • Hypnosis can encourage positive behaviors in children, such as cooperation during treatment, which can reduce the need for sedation or physical restraint.

4. Enhanced Relaxation:

   • The hypnotic state promotes deep relaxation, helping children feel more at ease in the dental environment.

Mechanism of Action

• Suggestibility: During hypnosis, children become more open to suggestions, allowing the dentist to guide their thoughts and feelings about the dental procedure.
• Focused Attention: The child’s attention is directed away from the dental procedure and towards calming imagery or positive thoughts, which helps reduce anxiety and discomfort.

Implementation in Pediatric Dentistry

1. Preparation:

   • Prior to the procedure, the dentist should explain the process of hypnosis to both the child and their parents, addressing any concerns and ensuring understanding.

2. Induction:

   • The dentist may use various techniques to induce a hypnotic state, such as guided imagery, progressive relaxation, or verbal suggestions.

3. Suggestion Phase:

   • Once the child is in a relaxed state, the dentist can provide positive suggestions related to the procedure, such as feeling calm, relaxed, and pain-free.

4. Post-Hypnosis:

   • After the procedure, the dentist should gradually bring the child out of the hypnotic state, reinforcing positive feelings and experiences.

Self-Mutilation in Children: Causes and Management

Overview of Self-Mutilation

Self-mutilation through biting and other forms of self-injury can be a significant concern in children, particularly those with severe emotional disturbances or specific syndromes. Understanding the underlying causes and appropriate management strategies is essential for healthcare providers.

Associated Conditions

1. Lesch-Nyhan Syndrome (LNS):

   • A genetic disorder characterized by hyperuricemia, neurological impairment, and self-mutilating behaviors, including biting and head banging.
   • Children with LNS often exhibit severe emotional disturbances and may engage in self-injurious behaviors.

2. Congenital Insensitivity to Pain:

   • A rare condition where individuals cannot feel physical pain, leading to a higher risk of self-injury due to the inability to recognize harmful stimuli.
   • Children with this condition may bite or injure themselves without understanding the consequences.

3. Autism:

   • Children with autism may engage in self-injurious behaviors, including biting, as a response to sensory overload, frustration, or communication difficulties.
   • Friedlander and colleagues noted that facial bruising, abrasions, and intraoral traumatic ulcerations in autistic children are often the result of self-injurious behaviors rather than abuse.

Management Strategies

Management of self-mutilation in children requires careful consideration of the underlying condition and the child's developmental stage. Two primary approaches are often discussed:

1. Protective Appliances:

   • Mouthguards:
     • Littlewood and Mitchell reported that mouthguards can be beneficial for children with congenital insensitivity to pain. These devices help protect the oral cavity from self-inflicted injuries.
     • Mouthguards can serve as a temporary measure until the child matures enough to understand and avoid self-mutilating behaviors, which is typically learned through painful experiences.

2. Surgical Procedures:

   • In some cases, surgical intervention may be necessary to address severe self-injurious behaviors or to repair damage caused by biting.
   • The decision to pursue surgical options should be made on a case-by-case basis, considering the child's overall health, the severity of the behaviors, and the potential for improvement.

3. Pharmacological Interventions:

   • Carbamazepine:
     • Cusumano and colleagues reported that carbamazepine may be beneficial for children with Lesch-Nyhan syndrome. This medication can help manage behavioral symptoms and reduce self-injurious behaviors.

Indications for Stainless Steel Crowns in Pediatric Dentistry

• Extensive Tooth Decay:
  Stainless steel crowns (SSCs) are primarily indicated for teeth with significant decay that cannot be effectively treated with fillings. They provide full coverage, preventing further decay and preserving the tooth's structure.

• Developmental Defects:
  SSCs are beneficial for teeth affected by developmental conditions such as enamel dysplasia or dentinogenesis imperfecta, which make them more susceptible to decay.

• Post-Pulp Therapy:
  After procedures like pulpotomy or pulpectomy, SSCs are often used to protect the treated tooth, ensuring its functionality and longevity.

• High Caries Risk:
  For patients who are highly susceptible to caries, SSCs serve as preventive restorations, helping to protect at-risk tooth surfaces from future decay.

• Uncooperative Patients:
  In cases where children may be uncooperative during dental procedures, SSCs offer a quicker and less invasive solution compared to more complex treatments.

• Fractured Teeth:
  SSCs are also indicated for restoring fractured primary molars, which are crucial for a child's chewing ability and overall nutrition.

• Special Needs Patients:
  Children with special needs who may struggle with maintaining oral hygiene can benefit significantly from the durability and protection offered by SSCs.

Contraindications for Stainless Steel Crowns

1. Allergy to Nickel:

   • Some patients may have an allergy or sensitivity to nickel, which is a component of stainless steel. In such cases, alternative materials should be considered.

2. Severe Tooth Mobility:

   • If the tooth is severely mobile due to periodontal disease or other factors, placing a stainless steel crown may not be appropriate, as it may not provide adequate retention.

3. Inadequate Tooth Structure:

   • If there is insufficient tooth structure remaining to support the crown, it may not be feasible to place an SSC. This is particularly relevant in cases of extensive decay or fracture.

4. Active Dental Infection:

   • If there is an active infection or abscess associated with the tooth, it is generally advisable to treat the infection before placing a crown.

5. Patient Non-Compliance:

   • In cases where the patient is unlikely to cooperate with the treatment or follow-up care, the use of SSCs may not be ideal.

6. Aesthetic Concerns:

   • In anterior teeth, where aesthetics are a primary concern, parents or patients may prefer more esthetic options (e.g., composite crowns or porcelain crowns) over stainless steel crowns.

7. Severe Malocclusion:

   • In cases of significant malocclusion, the placement of SSCs may not be appropriate if they could interfere with the occlusion or lead to further dental issues.

8. Presence of Extensive Caries in Adjacent Teeth:

   • If adjacent teeth are also severely decayed, it may be more beneficial to address those issues first rather than placing a crown on a single tooth.