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.

Caries Detection Method Comparison

 EXAM NOTES:

1. Bitewing radiographs - Most accepted overall
2. Visual-tactile - Most commonly used
3. DIAGNOdent - Best for occlusal surfaces
4. FOTI - Good for anterior approximal

Must Remember Points:

• HBSS maintains PDL cell viability for 24 hours
• Milk is the most practical storage medium
• Water causes osmotic lysis of PDL cells
• Primary teeth are NOT replanted
• Flexible splinting for 1-2 weeks only
• Pulp necrosis occurs in 85-96% of cases

Mnemonics:

• Storage media (Best to Worst): "Very Happy Medical Students Study Well" (Viaspan, HBSS, Milk, Saliva, Saline, Water)
• Avulsion management: "Time, Temperature, Transport, Treatment" (4 T's)

12 Primary + 12 Permanent Teeth Seen at: 8.5 Years

Detailed Mixed Dentition Timeline:

• 6-7 years: First permanent molars erupt + central incisors exchange
• 7-8 years: Lateral incisors exchange
• 8-8.5 years: Peak mixed dentition (12 primary + 12 permanent)
• 9-10 years: Canines and premolars exchange
• 11-12 years: Second molars erupt

Teeth Present at 8.5 Years:

Primary Teeth (12):

• Canines: 4 (C, C̄, C̄, C)
• First molars: 4 (D, D̄, D̄, D)
• Second molars: 4 (E, Ē, Ē, E)

Permanent Teeth (12):

• Central incisors: 4 (1, 1̄, 1̄, 1)
• Lateral incisors: 4 (2, 2̄, 2̄, 2)
• First molars: 4 (6, 6̄, 6̄, 6)

Space Maintainers: A fixed or removable appliance designed to maintain the space left by a prematurely lost tooth, ensuring proper alignment and positioning of the permanent dentition.

Importance of Primary Teeth

• Primary teeth serve as the best space maintainers for the permanent dentition. Their presence is crucial for guiding the eruption of permanent teeth and maintaining arch integrity.

Consequences of Space Loss

When a tooth is lost prematurely, the space can change significantly within a six-month period, leading to several complications:

• Loss of Arch Length: This can result in crowding of the permanent dentition.
• Impaction of Permanent Teeth: Teeth may become impacted if there is insufficient space for their eruption.
• Esthetic Problems: Loss of space can lead to visible gaps or misalignment, affecting a child's smile.
• Malocclusion: Improper alignment of teeth can lead to functional issues and bite problems.

Indications for Space Maintainers

Space maintainers are indicated in the following situations:

1. If the space shows signs of closing.
2. If using a space maintainer will simplify future orthodontic treatment.
3. If treatment for malocclusion is not indicated at a later date.
4. When the space needs to be maintained for two years or more.
5. To prevent supra-eruption of opposing teeth.
6. To improve the masticatory system and restore dental health.

Contraindications for Space Maintainers

Space maintainers should not be used in the following situations:

1. If radiographs show that the succedaneous tooth will erupt soon.
2. If one-third of the root of the succedaneous tooth is already calcified.
3. When the space left is greater than what is needed for the permanent tooth, as indicated radiographically.
4. If the space shows no signs of closing.
5. When the succedaneous tooth is absent.

Classification of Space Maintainers

Space maintainers can be classified into two main categories:

1. Fixed Space Maintainers

•  These are permanently attached to the teeth and cannot be removed by the patient. Examples include band and loop space maintainers.

  Common types include:

  • Band and Loop Space Maintainer:

    • A metal band is placed around an adjacent tooth, and a wire loop extends into the space of the missing tooth. This is commonly used for maintaining space after the loss of a primary molar.

  • Crown and Loop Space Maintainer:

    • Similar to the band and loop, but a crown is placed on the adjacent tooth instead of a band. This is used when the adjacent tooth requires a crown.

  • Distal Shoe Space Maintainer:

    • This is used when a primary second molar is lost before the eruption of the permanent first molar. It consists of a metal band on the first molar with a metal extension (shoe) that guides the eruption of the permanent molar.

  • Transpalatal Arch:

    • A fixed appliance that connects the maxillary molars across the palate. It is used to maintain space and prevent molar movement.

  • Nance Appliance:

    • Similar to the transpalatal arch, but it has a small acrylic button that rests against the anterior palate. It is used to maintain space in the upper arch.

2. Removable Space Maintainers

• These can be taken out by the patient and are typically used when more than one tooth is lost. They can also serve to replace occlusal function and improve esthetics.

  Common types include:

  • Removable Partial Denture:

    • A prosthetic device that replaces one or more missing teeth and can be removed by the patient. It can help maintain space and restore function and esthetics.

  • Acrylic Space Maintainer:

    • A simple acrylic appliance that can be used to maintain space. It is often used in cases where esthetics are a concern.

  • Functional Space Maintainers:

    • These are designed to provide occlusal function while maintaining space. They may include components that allow for chewing and speaking.

Types of Removable Space Maintainers

• Non-functional: Typically used when more than one tooth is lost.
• Functional: Designed to provide occlusal function.

Advantages of Removable Space Maintainers

1. Easy to clean and maintain proper oral hygiene.
2. Maintains vertical dimension.
3. Can be worn part-time, allowing circulation of blood to soft tissues.
4. Creates room for permanent teeth.
5. Helps prevent the development of tongue thrust habits into the extraction space.

Disadvantages of Removable Space Maintainers

1. May be lost or broken by the patient.
2. Uncooperative patients may not wear the appliance.
3. Lateral jaw growth may be restricted if clasps are incorporated.
4. May cause irritation of the underlying soft tissues.

Salivary Flow Rate Assessment

Normal Values:

• Stimulated whole saliva: 1-3 ml/min
• Unstimulated whole saliva: 0.3-0.4 ml/min
• Hyposalivation: <0.1 ml/min unstimulated

Collection Methods:

1. Spitting method: Most common
2. Suction method: For compromised patients
3. Paraffin wax stimulation: Standardized approach

Salivary Buffer Capacity

Testing Methods:

• Dentobuff system: Commercial kit
• pH measurement: Before and after acid challenge
• Clinical significance: Caries resistance indicator

Bacterial Counts

Streptococcus mutans:

• Low risk: <10⁵ CFU/ml
• High risk: >10⁶ CFU/ml
• Testing: Saliva-Check Mutans

Lactobacillus:

• Low risk: <10⁴ CFU/ml
• High risk: >10⁵ CFU/ml
• Significance: Caries progression indicator