40 Questions
What is an advantage of intra oral scanning over traditional impressions?
Less patient discomfort
What is necessary for taking digital impressions?
Moisture control and soft tissue retraction
What is the purpose of CAD in intra oral scanning?
To design the prosthesis
What is the difference between contact and non-contact digitizing?
Contact digitizing uses a probe, while non-contact digitizing uses laser light
What is the advantage of non-contact digitizing over contact digitizing?
It is relatively quick in gathering data
What is the purpose of CT scan and MRI in CAD-CAM?
To acquire data for CAD-CAM
What is a limitation of digital impression technique?
It requires careful moisture control and soft tissue retraction
What is the role of the CAD system in intra oral scanning?
To design the prosthesis
What is the fourth component in the CAD/CAM dental chain?
NCMT (Numerical Control Machine Tools)
What type of manufacturing process involves removing materials?
Subtractive manufacturing
What is the name of the process that involves adding materials?
Additive manufacturing
What are the main additive processes for formatting?
SLA, FDM, LM, and SLS
What type of CAD/CAM method enables the practitioner to construct a prosthesis in one single session?
Direct CAD/CAM
What type of CAD/CAM method requires at least one visit to a dental surgery?
Semi-direct CAD/CAM
What type of CAD/CAM method involves sending a standard manual chemical impression to the prosthetist or machining centre?
Indirect CAD/CAM
What type of impression is processed on site in Direct CAD/CAM?
Intra-oral optical impression
What factor determines the materials used in CAD/CAM?
Manufacturing process adopted
What types of ceramics are used in CAD/CAM?
All of the above
What is the purpose of CAM production in dentistry?
To compensate for shrinkage
What is the result of milling a partially sintered zirconia block?
Final dimensions and density are achieved
What is a feature of modern CAD/CAM materials?
Multi-chromatic and translucent
What was the result of the study on marginal adaptation of Y-TZP bridges?
The marginal adaptation was not affected by milling time
What has CAD/CAM enabled in restorative dentistry?
The development of ceramic-based restorations
What is an application of CAD/CAM in orthodontics?
Developing invisible alignment trays
What is the primary difference between additive and subtractive techniques in CAD/CAM manufacturing?
The application of material versus cutting from a solid block
What is the purpose of the presintered stage in ceramic processing?
To prepare the material for milling or grinding
What is a benefit of CAD/CAM in dentistry?
Improved efficiency in manufacturing
What is a type of prosthesis that can be created with CAD/CAM?
Removable prostheses on implants
What type of ceramics are commonly used in CAD/CAM restorations?
Glass ceramics
What is a benefit of using CAD/CAM restorations?
They offer excellent esthetics, biocompatibility, and wear resistance
What is a software solution developed by CAD/CAM for orthodontics?
Invisalign
What is the final step in the processing of ceramic materials in CAD/CAM manufacturing?
Sintering
What is one of the advantages of digital technology in medical devices?
Ensuring consistency and optimising traceability
What is necessary for practitioners to master the digital technique?
A training phase learning to handle new materials and tools
What is one of the benefits of CAD/CAM technology for patients?
Enjoying restorations that are more aesthetically pleasing and biocompatible
What is dematerialising in the context of the prosthetic chain?
Avoiding the accumulation of inaccuracies inherent in traditional techniques
What is one of the advantages of using CAD/CAM technology for practitioners?
Developing their professional skills on a daily basis
What is a benefit of eliminating the physical impression stage in CAD/CAM?
Reducing patient discomfort
What is a result of the development of new, innovative materials in CAD/CAM?
Increasing the need for safety and quality standards
What is one of the ways practitioners can set themselves apart from the competition using CAD/CAM?
By enhancing their work and their surgery's technical platform
Study Notes
CAD/CAM Systems for Dentistry
- CAD/CAM systems produce a framework that compensates for shrinkage by creating an enlarged framework.
- A partially sintered zirconia block is selected for milling, and then undergoes sintering to attain final dimensions, density, and strength.
Marginal Adaptation
- Studies have shown that the marginal adaptation of Y-TZP bridges processed with the Lava system for 2 milling times (75 mins vs 56 mins) did not affect the marginal adaptation (61±25 μm vs 59±21 μm).
CAD/CAM Manufacturing Systems
- CAD/CAM systems use additive or subtractive techniques to manufacture restorations.
- Additive techniques include:
- Stereolithography
- 3D printing
- Resin
- Selective laser sintering
- Subtractive techniques include:
- Milling
- Cutting from a solid block
- Pressing/milling
Restorative Materials for CAD/CAM
- CAD/CAM systems can be used with various ceramic materials, including:
- Presintered alumina or zirconia blocks
- Veneer ceramics
- Glass ceramics (e.g., Dicor, Vita Mark II)
- These materials offer excellent esthetics, biocompatibility, color stability, low thermal conductivity, and wear resistance.
Advantages and Disadvantages of CAD/CAM
- Advantages:
- Less patient discomfort
- Takes less time
- No need for model pouring
- No extra space required to keep models
- Disadvantages:
- More patient discomfort (traditional method)
- Takes more time (traditional method)
- Model pouring is needed (traditional method)
- Shelves are required to keep models (traditional method)
Intra Oral Scanning
- Intra oral scanning systems available in the market include:
- CEREC by Sirona Dental System GMBH (DE)
- Lava C.O.S. by 3M ESPE (US)
- iTero by CADENT LTD (IL) and TECHNOLOGIES, LLC (US)
- These systems take 3-D virtual pictures of the prepared tooth/teeth and adjacent structures directly into the patient's mouth.
Digital Impression Techniques
- Digital impression techniques include:
- Intra oral scanning
- Contact and non-contact digitizing
- CT scan/MRI
- These techniques require consideration of factors such as moisture control, soft tissue retraction, and hemostasis.
CAD/CAM Technologies
- CAD/CAM technologies include:
- Direct CAD/CAM: enables the practitioner to construct a prosthesis in one single session
- Semi-direct CAD/CAM: requires at least one visit to a dental surgery; the data can be processed in the surgery or transmitted to an online laboratory or machining center
- Indirect CAD/CAM: the practitioner produces a standard manual chemical impression that is sent to the prosthetist or machining center
Applications of CAD/CAM
- CAD/CAM technology has led to the improvement of existing therapeutic solutions and paved the way for new solutions
- Applications include:
- Restorative dentistry
- Prosthetics
- Implantology
- Oral surgery
- Orthodontics
- CAD/CAM can be used for indirect restorations, single and multiple fixed prostheses, inlay cores, dental veneers, supra-implantary prostheses, and even temporary prostheses.
This quiz covers the processing of zirconia blocks using CAD/CAM technology in dentistry. It explores the effects of milling and sintering on the framework's dimensions, density, and strength.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
