Podcast Beta
Questions and Answers
What is the ideal taper angle for tooth preparation to ensure proper retention?
Which factor contributes to the dislodgement of crowns in tooth preparation?
What type of force is primarily associated with the rotation or tipping of a crown during placement?
How can circumferential irregularities affect crown placement?
Signup and view all the answers
What implication does a shorter axial wall height have in tooth preparation?
Signup and view all the answers
Which of the following statements is true regarding the path of insertion for crown preparation?
Signup and view all the answers
Which condition increases the risk of rotational dislodgement in a crown?
Signup and view all the answers
What role does the axis of rotation play in crown retention for tooth preparations?
Signup and view all the answers
Which finish line type is characterized by a very thin profile and is typically used for mandibular incisors?
Signup and view all the answers
What is the primary purpose of the finish line in dental preparations?
Signup and view all the answers
Which type of finish line is described as having a right angle gingival termination and is used in porcelain crowns?
Signup and view all the answers
Which occlusal irregularity is important to follow during crown preparation?
Signup and view all the answers
Which finish line type is rounded and has an obtuse angle gingival termination, commonly used for metal restorations?
Signup and view all the answers
What can a poor marginal seal potentially lead to?
Signup and view all the answers
Which type of finish line would likely cause injury to tissues if not designed properly?
Signup and view all the answers
What should be checked by looking at the occlusal during a dental preparation?
Signup and view all the answers
What is a key reason for using coolants during tooth preparation?
Signup and view all the answers
Which finish line is placed specifically within the sulcus?
Signup and view all the answers
How can the preservation of tooth structure be maximized during preparation?
Signup and view all the answers
What is the effect of under-reduction in tooth preparation?
Signup and view all the answers
Which factor does NOT contribute to heat generation during tooth preparation?
Signup and view all the answers
In terms of circumferential irregularities, which preparation taper is preferred?
Signup and view all the answers
Which type of finish line is located above the marginal gingiva?
Signup and view all the answers
What is a consequence of using excessive pressure during the tooth preparation process?
Signup and view all the answers
Study Notes
Occlusal Irregularity
- Beveled shoulder finish line aids in maintaining structural integrity of the crown.
- Marginal ridges can be modified for optimal crown fit.
- Follow normal anatomical occlusal irregularities for precision.
Structural Durability
- Finish line marks the transition between prepared and unprepared tooth surfaces.
- A good marginal seal prevents food debris, fluids, and bacteria from entering the crown.
- Poor seal leads to halitosis and tooth demineralization.
Finish Line Requirements
- Knife Edge: Thin finish line, ideal for small mandibular incisors.
- Chamfer Finish Line: Rounded, with obtuse angle termination; suitable for metal restorations.
- Shoulder Finish Line: Right angle termination with ledge; used for porcelain crowns.
Biologic Principles
- Preparations must maintain compatibility with oral tissues to avoid injury.
- Structural preparation should consider tooth preservation and impact on surrounding tissues.
Taper of Preparation
- Excessive taper can lead to crown dislodgement.
- Ideal axial wall taper is 3-5 degrees; over-tapering decreases retention.
- Single unit restorations, such as crowns, are particularly susceptible to rotational dislodgement.
Circumferential Irregularity
- Vertical irregularities are crucial for retention.
- Apically directed irregularities help counteract forces from hard food.
- Irregular crown shapes must be retained to prevent twisting or rotation.
Beveled Shoulder Finish Line
- Combines features of a shoulder line with a small bevel to enhance fit.
- Preservation of tooth structure is vital to prevent pulp irritation; avoid exceeding 2mm reduction.
- Use intermittent reduction techniques to manage heat generation during preparation.
Esthetic Principles
- Crowns and bridges should mimic natural teeth in color, form, size, and shape.
- Under-reduction can result in bulky restorations.
Other Considerations
- Techniques must avoid damaging gingival tissues; understand finish line positions:
- Supra-gingival: Above the gingiva
- Equal gingival: At marginal gingiva level
- Sub-gingival: Within the gingival sulcus.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
Explore the concepts of occlusal irregularity, including beveled shoulders and chamfer techniques in dental anatomy. This quiz covers the significance of marginal ridges and how they relate to normal occlusal features. Test your understanding of these essential dental practices.
