Tooth-Supported Removable Dentures Quiz

Tooth-Supported Removable Dentures

• Tooth-supported removable dentures (overdentures) are a type of prosthetic device used for patients missing some or all natural teeth.
• Complete dentures (total overdentures) or partial dentures (removable partial overdentures) are supported by existing natural teeth, roots, or implants.
• Overdentures help maintain oral health and functionality, improving oral function and appearance.
• Patients with fewer natural teeth are often candidates for overdenture treatment.
• Overdentures can avoid the need for completely edentulous treatment and maintain alveolar bone, which is frequently lost with complete dentures.
• They may lessen the problems associated with conventional complete dentures including bone resorption and loss of oral function.

Types of Overdenture Prostheses

• Overlay Dentures
• Superposition appliances
• Telescopic Prosthesis
• Hybrid Prosthesis

Overdenture Prosthesis Treatment

• Overdenture treatment involves the placement of a denture over remaining teeth or implants.
• The supporting teeth are prepared or treated through endodontics prior to placement and fitting of a coping.
• Coping types include short, long, medium-short, and medium preparations that are tailored to the remaining teeth condition.
• Different types of attachments are employed to improve retention and stability.
• The final overdenture is fashioned and fixed to the specific patient.

Overdenture Advantages

• Increases support, retention, and stability
• Easier for patients to adapt to
• Decreases forces on the bone
• Provides psychological relief
• Easily convertible to traditional full dentures if supporting teeth are lost.

Overdenture Disadvantages

• Additional treatment and attachments may increase cost.
• Construction may take more time.
• Potential risk of falling, abrasion, loss, breakage or rupture of attachments.
• Potential for denture base thinning and breakage due to muscle strength and supporting tooth number.
• Difficult to care for due to complex structure potentially leading to oral hygiene problems.
• Requires regular patient checkups.
• This should be taken into account for physically handicapped patients.
• Overdentures may not be suitable for all cases due to patients' health concerns and costs, making appropriate case selection crucial.

Indications for Overdenture Treatment

• Patients with single complete dentures
• Cleft palate problems, surgical defect cases, and trauma patients
• Hypodontia cases
• Significant tooth wear (reducing vertical dimension of the mouth) situations
• Complex cases needing considerable adjustments
• Cases requiring support needed for removable partial dentures
• Patients committed to oral hygiene to preserve existing teeth

Contraindications for Overdenture Treatment

• Patients with difficulty maintaining oral hygiene (physical or mental complications) and who are at risk of swallowing the prosthesis.
• Patients with complications in root canal treatment.
• Excessively curved tooth roots.
• Insufficient interocclusal space.
• Cases with Class II or Class III bone configurations that prevent proper anterior esthetics.
• Patients who cannot afford additional costs.

Classification of Overdentures

• Classified by construction time (immediate, interim, permanent)
• Classified by support type (teeth- or implant-supported)
• Classified by coping use (no coping, coping, telescopic attachment)
• Classified by material type (acrylic or metal base)

Types of Overdenture Construction

• Immediate: A temporary overdenture made before modifications or procedures are completed.
• Temporary: A transitional or preparation-phase overdenture, substituting for a traditional partial denture while waiting for the permanent overdenture.
• Permanent: Final prosthesis fabricated after clinical and laboratory procedures.

Supporting Teeth Without Copings

• Selected abutments are shortened to a 2-3 mm coronal height.
• The surface is contoured to a convex or dome shape.
• Commonly require endodontic treatment and amalgam or composite restoration.

Supporting Teeth With Coping

• A cast metal coping, fitted for the tooth.
• Typically dome-shaped and finished at gingival margin.
• May be short (on short crowns) or long (requires larger crown/root).

Supporting Teeth With Attachments

• Precision devices improving denture base retention.
• Usually attached to abutments via a casting coping
• Components are male and female parts.

Rigid Vs Flexible Attachments

• Rigid: No base movement, ensures adequate retention, high torque risk.
• Flexible: Partial base control, less torque risk.

Examination and Diagnosis

• Anamnesis (medical and dental history)
• Clinical examination (periodontal condition, endodontic evaluation, caries activity, bone support, number and position of support structures, axial slope/root form, chewing forces, antagonist dentition and appropriate denture design)
• Radiography (Panoramic, periapical)

Treatment Plan and Course

• Correct diagnosis and patient expectations discussed.
• Necessary periodontal/endodontic treatment and surgical procedures completed.
• Immediate overdenture placed followed by permanent prosthesis.
• Selection, preparation of supporting structures, fabrication of copings, and complete denture construction process.

Periodontal Condition of Supporting Teeth

• Amount of alveolar bone (especially important)
• Proper crown/root ratio for incoming force resistance
• Manageable periodontal pocket depth
• Adequate attached gingiva

Position of Supporting Teeth

• Teeth enduring significant occlusal forces should be prioritized.
• Anterior portion of both dental arches is resorption-prone.
• Canines or premolars are favored for supporting structures to aid in overdenture function.
• The maxillary canines protect the maxillary from excessive stress during mandibular function.
• Mandible teeth (especially canines) are crucial for stabilizing the lower denture and are typically last remaining teeth.
• Isolated teeth can also serve as advantageous abutments.
• Preservation of teeth in both dental arches helps optimize occlusal vertical dimension.
• Strategic positions in the arch support and stabilize an overdenture.

Path of Insertion

• If necessary, undercut areas on remaining teeth (especially labial contours and lingual undercuts) may necessitate modifications to prevent denture tissue damage.

Endodontic Evaluation

• Root canal treatment may be necessary to shorten the clinical crown length of a tooth to fit under the prosthesis.
• Single canal teeth present fewer problems.
• Vital molars are exceptions to shortening, as thin, low-level copings can be used without treatment for retention advantages.

Preparation of Supporting Teeth

• Four main types of preparation techniques for using primary copings include short, medium-short, and medium (for vital and non-vital teeth) and long preparation techniques, each serving a specific purpose related to patient needs and the nature of the remaining teeth.

Coping Types

• Primary – fits on prepared supports.
• Long (6-8mm)
• Medium (4-6mm)
• Medium-Short (2-4mm)
• Short (1-2mm)
• Secondary - sits upon the primary coping.

Preparation of Prostheses

• Impressions are taken after the supporting structures are completed.
• Elastomeric material and acrylic trays are used.
• Model obtained.

Temporary Base Plates and Jaw Relations

• Alignment and jaw relationships established.
• Any problems with tooth placement addressed (teeth reductions).
• Prosthesis completed after modeling and acrylic fabrication.
• Final patient mouth adaptation performed via pressure pastes.

Assessment Criteria for Overdenture Success

• Adequate support, retention, and stability.
• Patient comfort and satisfaction.
• Aesthetic, phonetic, and functional aspects of the prosthesis.
• Occlusal contacts compatible with mandible movements.

Periapical Tissue of Support Teeth

• Periapical tissue evaluated similarly to natural teeth.
• Supporting teeth should exhibit radiographically healthy lamina dura.

Clinical Crowns

• Caries detection is critical.
• Teeth are prepared, contoured, and polished to allow easy denture removal.

Cast Gold Copings

• Use constrained by tooth structure. Not appropriate for all cases; may not provide acceptable contours for amalgam restoration.

Long-Term Overdenture Treatment Use

• Treatment success depends on patient protection of supporting structures.
• Post prosthetic application, natural stimulation/cleaning of supporting tissues is reduced.
• Oral and prosthetic hygiene training is essential.

Functional Reduction Impact

• Reduces keratinization in adjacent tissues and potentially increases injury/trauma risks.
• Comprehensive oral hygiene education required.

Oral Hygiene for Overdenture Care

• Patients advised to brush around supporting structures.
• Use appropriate tooth brushing, interproximal brushing usage, and dental floss.
• Soft brushes used for soft tissues.
• Fluoride or chlorhexidine mouthwashes are potentially useful.
• Prostheses removed daily for brushing and soaking in a cleaning solution.

Example Cases

• Overdenture types illustrated (ball attachments, custom abutments, telescopic crowns).
• Images shown of different stages of overdenture treatment on patients with variable tooth conditions.
• Relevant treatment protocols for examples provided by clinicians are included.

References

• Provided are references by relevant researchers or experts in overdenture treatment.

Test your knowledge on tooth-supported removable dentures and their associated benefits, risks, and preparation techniques. This quiz covers critical concepts such as overdentures, patient adaptation, and criteria for success. Challenge yourself and enhance your understanding of this crucial aspect of dental prosthetics.