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Zinc Phosphate Cement 2019 Self-Study Course #2 Course Course Instructions: . Read and review the course materials. Complete the 8 question test. A total of 6 questions must be answered correctly for credit. Submit your answers online at: http://dentistry.osu.edu/sms- Frequently Asked Contact Us: continuing-education Questions: . Check your email for your CE Q: Who can earn FREE CE credits? Phone certification of completion (please check your junk/spam 614-292-6737 A: EVERYONE - All dental professionals folder as well). in your office may earn free CE credits. Each person must read the course Toll Free materials and submit an online answer 1-888-476-7678 About SMS CE courses: form independently. TWO CREDIT HOURS are issued Q: Where can I find my SMS number? Fax for successful completion of this self-study course for the OSDB A: Your SMS number can be found in the 614-292-8752 2019-2021 biennium totals. upper right hand corner of your monthly reports, or, imprinted on the back of . CERTIFICATE of COMPLETION E-mail is used to document your CE your test envelopes. The SMS number is the account number for your office only, [email protected] credit and is emailed to each course participant. and is the same for everyone in the office. ALLOW 2 WEEKS for processing Web of your certificate. Q: How often are these courses dentistry.osu.edu/sms available? A: Four times per year (8 CE credits). The Ohio State University College of Dentistry is a recognized provider for ADA CERP credit. ADA CERP is a service of the American Dental Association to assist dental professionals in identifying quality providers of continuing dental education. ADA CERP does not approve or endorse individual courses or instructors, nor does it imply acceptance of credit hours by boards of dentistry. Concerns or complaints The Ohio State University about a CE provider may be directed to the provider or to the Commission for Continuing Education Provider Recognition at www.ada.org/cerp. College of Dentistry The Ohio State University College of Dentistry is approved by the Ohio State Dental Board as a 305 W. 12th Avenue permanent sponsor of continuing dental education. Columbus, OH 43210 This continuing education activity has been planned and implemented in accordance with the standards of the ADA Continuing Education Recognition Program (ADA CERP) through joint efforts between The Ohio State University College of Dentistry Office of Continuing Dental Education and the Sterilization Monitoring Service (SMS). 2019 General Review of Course Luting Agents This is an OSDB Category B: Supervised self-instruction course #2 About the Author Francisco X. Azpiazu Flores, DMD Dr. Azpiazu’s education includes Dental surgery degree from the Autonomous University of Nicaragua, a 2 –year Advanced Education in General Dentistry Program from the University of Connecticut. Currently he is enrolled in the Advanced Prosthodontics Programs of The Ohio State University where he is finishing his first year of residency. Before coming to the United States to continue his dental education he practiced general dentistry for 2 years in Nicaragua in addition to work as an assistant professor in his Alma mater in the class of Operative Dentistry and Dental Anatomy. Dr. Azpiazu can be reached at [email protected] Written by: Neither I nor my immediate family have any financial interests that Francisco X. Azpiazu, DMD would create a conflict of interest or restrict my judgement with regard to the content of this course. Edited by: Introduction Sydney Fisher, MPH Nick Kotlar, BS Dental cements have been used in dentistry since the early days of this profession. Although ‘‘no available product satisfies the requirements for an ideal luting agent,” there are some cements that have a long history of service, with proven efficiency and Release Date: reliability. Dental cements such as zinc phosphate cement, for May 13, 2019 example, have been used to cement indirect restorations for more 8:30am EST than a century with excellent results and have a well-documented clinical behavior. With the advent of newer cements with innovative formulations and “universal” indications of use, less Last Day to Take Course and less attention has been given to the more traditional types of Free of Charge: cements. Hill (2007) stated that “comprehensive patient care requires several materials” and the “choice is not always easy,” June 13, 2019 implying that the selection of the luting agent to be used must be 4:30pm EST an intelligent and practical process. A deep understanding of the different physical properties of the different types of cement available is necessary, and while a one-type-fits-all type of cement could be used for every situation, it may not be the best choice every time. In the upcoming pages of this course, a brief review of the different physical and chemical properties of the luting agents will be provided, in addition to a review of their2 use and clinical indications. Definition & Applications of Dental Cements Extracted from Proper Selection of Contemporary Dental Cements, Yu et al. (2014) Based on the 9th edition of The Glossary of Prosthodontics Terms, dental cement can be defined as a “binding element or agent used as a substance to make objects adhere to each other, something serving to firmly unite, or a material that, on hardening, will fill a space or bind adjacent objects.” According to O’Brien (2002) and McCabe & Walls (2009), the dental cements can be used as: 1. Luting agents to bond preformed restorations and orthodontic attachments in or on the tooth 2. Cavity liners and bases to protect the pulp, and foundations and anchors for restorations 3. Restorative materials 4. Root canal sealers Although there are many indications for the use of dental cements, this short course will emphasize the “luting” property of dental cements. What does luting mean? The word ‘luting’ implies the use of a moldable substance to seal a space or to cement two components together (Anusavice, Shen, & Rawls 2003). A dental luting agent can also be defined as both: 1. A viscous material placed between tooth structure and a prosthesis that hardens through chemical reactions to firmly attach the prosthesis to the tooth structure (Anusavice et al., 2003), 2. Any material used to attach or cement indirect restorations to prepared teeth (Ferro, 2017). Anusavice et al. (2003) and McCabe & Walls (2009) state that in order to guarantee an adequate clinical functionality, the luting materials must fulfill the following requirements: 1. Should be esthetic in nature. 2. Must be biocompatible without harming the tooth or its surrounding tissues. 3. Must have adequate film thickness. When compressed, the material should be able to flow between the surfaces being cemented to a thickness that allows the seating of the restoration. According to the ANSI/ADA Specification No. 96, freshly mixed cement is placed between two optically flat surfaces and a 150 Newton (N) vertical load is applied. The film should be continuous, and no voids should exist through the entire body of the film. For luting applications, the maximum allowable film thickness according to the ANSI/ADA specification No. 96 is 25µm. 4. Should allow sufficient time for mixing the material, applying to the restoration and/or tooth preparation and for seating the restoration in place in the mouth. 5. Should, ideally, give thermal and electrical insulation since many of the restoration commonly cemented to teeth are based on alloys (e.g. gold crowns). 6. Must provide retention to dental restorations on setting. The cement should provide mechanical resistance to the displacement of the restoration, and must be strong enough to resist fracture when loads are applied to the restoration. 7. Must have low solubility when exposed to the oral environment. 8. Must have adequate manipulation properties. The manipulation, including dispensation of the ingredients, should allow for some margin of error in practice and should allow easy removal when removing the excess of cement. Although some dental cements have very good physical properties and can fulfill the majority of the properties mentioned above, “no available product satisfies all the requirements for an ideal luting agent” (Hill, 2007). One of the most important functions of a luting agent is to fill the minute void between the tooth preparation (or implant abutment) and restoration interface in order to mechanically lock the restoration in place to prevent dislodgement during function (Hill, 2009; Lott, 2011). Excerpted from Phillips’ Science of Dental Materials (2003) When the prepared surface is seen in a microscope, the surfaces exhibits peaks and valleys. When two surfaces are placed against each other, there are only point contacts along the peaks leaving areas without contact between these. One of the principal objectives of dental cements is to fill and seal this spaces, for this purpose the material used should be fluid enough to flow into a continuous film without fragmentation, and should be compatible with both of the surfaces being cemented in order to prevent void development around the deep and narrow valleys of the preparation. Types of Dental Cements The American Dental Association (ADA) assesses the measurement of the clinically significant physical and chemical properties of dental materials and the development of new materials, instruments, and test methods. In 1966, the ADA Council on Dental Materials and Devices, now known as the Council on Scientific Affairs, assumed responsibility for standards development and initiated the certification of products that meet the requirements of these specifications. Such specifications are standards by which the quality and properties of particular dental materials can be gauged. These standards identify the requirements for the physical and chemical properties of a material that ensure satisfactory performance if the material is properly manipulated and used by the dentist and the dental laboratory technician.
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