Wear resistance of 3D-printed denture tooth resin opposing zirconia and metal antagonists

The Journal of Prosthetic Dentistry

Available online 27 November 2019
The Journal of Prosthetic Dentistry

Abstract

Statement of problem

Additive manufacturing technology can be used for denture bases and also denture teeth. Therefore, the mechanical properties of 3D-printed resin denture teeth should be evaluated.

Purpose

The purpose of this in vitro study was to compare the wear resistance of 3D-printed denture tooth resin with that of conventionally prefabricated denture teeth.

Material and methods

Eighty substrate specimens were prepared with 5 kinds of resin denture teeth: 3D-printed denture tooth resin (DENTCA denture tooth resin; DENTCA, Inc), Artic 6 (Kulzer GmbH), Preference (Candulor AG), Premium 6 (Kulzer GmbH), and Surpass (GC Corp). The 3D-printed denture tooth specimens were made of methacrylate-based photopolymerized resin by stereolithography 3D printing. Antagonistic surfaces were made from zirconia by milling and from cobalt-chromium (Co-Cr) alloy by 3D printing and casting. The specimens were loaded at 49 N for 30 000 cycles under thermocycling conditions in a mastication simulator. Wear resistance was measured by calculating the volume of substance lost. Wear surface characteristics were observed by using a scanning electron microscope (SEM). Two-way ANOVA was used to analyze the data (α=.05).

Results

The influence of the resin denture teeth and the type of antagonist were both statistically significant. The wear volume loss of the 3D-printed denture tooth resin was higher than that of Artic 6 and Preference when opposing the zirconia and the metal antagonists (P<.05). The 3D-printed denture tooth resin did not show a significant difference from Premium 6 with the zirconia and the metal antagonists or Surpass with the zirconia antagonist. From the SEM images, the specimens of the 3D-printed denture tooth resin showed a relatively smooth surface with the zirconia antagonist and exhibited cracks when opposed by the metal antagonist.

Conclusions

The results suggest that 3D-printing by using resin materials provides adequate wear resistance for denture tooth use.
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Behavioral sciences in the promotion of oral health

International & American Associations for Dental Research
Alexandria, VA, USA – 2019 marks the Centennial of the Journal of Dental Research (JDR). Over the last century the JDR has been dedicated to the dissemination of new knowledge and information on all sciences relevant to dentistry and to the oral cavity and associated structures in health and disease. To celebrate, the JDR is featuring a yearlong, commemorative article and podcast series that highlights topics that have transformed dental, oral and craniofacial research over the past 100 years.
The importance and value of behavioral sciences in dentistry has long been recognized and over time behavioral sciences have expanded our understanding of oral health beyond ‘disease’ to a broader biopsychosocial concept of oral health. In the JDR Centennial article "Behavioral Sciences in the Promotion of Oral Health," Colman McGrath, University of Hong Kong, SAR, China, discusses how this broadened view has led dentistry away from a focus of ‘treatment’ to oral health ‘care.’
"Over the past 100 years, key oral health behaviors have been identified including diet, oral hygiene and dental services, and the relationship between individual factors and the broader environmental factors have been increasingly emphasized, leading to a united call for action in addressing oral health inequalities," said McGrath.
"More recently behavioral therapies, such as cognitive behavioral therapy, are increasingly being employed in dental practice in the management of dental anxiety, pain and psychosomatic dental and oral problems with promising results," said McGrath. "There is a need to consider training for dental professionals, resources and tools for implementation and a systematic approach of what interventions to use, how to employ them, when and for how long, in addition to determining the cost effectiveness and benefits of such approaches."
Accompanying the article, the JDR Centennial podcast "Behavioral Sciences in the Promotion of Oral Health," features a conversation between McGrath and Lois Cohen, Consultant, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland, USA, moderated by JDR Associate Editor Falk Schwendicke of Charite University in Berlin, Germany.

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The December 2019 issue of the JDR also includes and Historical Highlight 13 on Germfree Animals for the Study of Dental Caries by JDR Associate Editor, Nicholas Jakubovics, Newcastle University, England.
The legacy of the JDR was honored during a celebration at the 97th General Session of the IADR, held in conjunction with the 48th Annual Meeting of the AADR and the 43rdAnnual Meeting of the Canadian Association for Dental Research, in Vancouver, British Columbia, Canada on June 19-22, 2019. For more information on the JDR Centennial, please visit: http://www.iadr.org/JDRcentennial.
Click here to view a PDF of this press release.
About the Journal of Dental Research
The IADR/AADR Journal of Dental Research (JDR) is a multidisciplinary journal dedicated to the dissemination of new knowledge in all sciences relevant to dentistry and the oral cavity and associated structures in health and disease. The JDR continues to rank #1 of 90 journals in Eigenfactor with a score of 0.021290, ranks #2 in Impact Factor of 90 journals in the "Dentistry, Oral Surgery & Medicine" category at 5.125 and ranks #2 of 90 in Article Influence with a score of 1.643.The JDR‘s 5-year Impact Factor has remained above 5 for the fourth year at 5.722, ranking #2 of 91 journals. With over 20,000 citations, the JDR also boasts the most citations in the "Dentistry, Oral Surgery & Medicine" category — 4,500 citations above the second ranked journal in the field.
International Association for Dental Research The International Association for Dental Research (IADR) is a nonprofit organization with over 10,000 individual members worldwide, with a Mission to drive dental, oral and craniofacial research to advance health and well-being worldwide. To learn more, visit http://www.iadr.org. The American Association for Dental Research (AADR) is the largest Division of IADR with 3,100 members in the United States. To learn more, visit http://www.iadr.org/aadr.

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Average Dentist Salary by State

Mean annual wage for dentists in every U.S. state
Rank State 2018 Average Salary 2017 Average Salary 2016 Average Salary 2015 Average Salary 2014 Average Salary 2013 Average Salary 5-Year Change
32 Alabama $171,900 $181,240 $183,480 $174,870 $173,220 $186,430 -8
2 Alaska $259,350 $237,140 $234,240 $217,120 $205,880 $208,650 24
20 Arizona $186,870 $175,310 $168,710 $155,940 $141,890 $154,260 21
37 Arkansas $165,480 $170,440 $185,170 $171,450 $160,520 $152,200 9
44 California $151,490 $157,890 $164,330 $170,490 $155,270 $147,750 3
28 Colorado $174,930 $168,110 $175,210 $178,710 $158,050 $143,910 22
6 Connecticut $213,390 $212,840 $205,310 $188,580 $183,460 $192,870 11
1 Delaware $264,440 $257,290 $236,130 $227,160 $224,830 $226,910 17
36 Florida $167,270 $166,610 $166,180 $170,270 $163,570 $153,260 9
27 Georgia $176,600 $181,690 $173,850 $177,540 $190,620 $189,550 -7
16 Hawaii $196,690 $174,070 $179,920 $154,880 $167,470 $152,810 29
31 Idaho $172,020 $187,800 $191,250 $191,140 $169,360 $154,810 11
33 Illinois $171,590 $161,270 $156,150 $149,400 $141,980 $133,260 29
24 Indiana $183,800 $185,820 $162,390 $146,760 $143,780 $157,930 16
19 Iowa $187,570 $193,130 $184,910 $185,270 $174,480 $171,610 9
25 Kansas $179,100 $185,600 $177,380 $182,340 $173,720 $152,040 18
40 Kentucky $154,230 $163,390 $176,730 $168,460 $150,950 $157,290 -2
49 Louisiana $124,020 $115,050 $126,030 $139,080 $148,240 $144,460 -14
11 Maine $203,920 $179,920 $191,200 $185,290 $203,890 $194,990 5
43 Maryland $151,950 $154,010 $165,140 $158,310 $159,830 $151,640 0
26 Massachusetts $177,410 $175,580 $188,020 $179,390 $175,280 $170,290 4
14 Michigan $197,490 $187,430 $172,270 $169,080 $161,040 $166,070 19
4 Minnesota $227,280 $210,320 $205,810 $193,320 $193,690 $193,100 18
42 Mississippi $153,810 $182,520 $172,600 $178,610 $152,490 $164,110 -6
17 Missouri $191,240 $180,350 $172,720 $166,000 $168,650 $165,930 15
34 Montana $170,260 $161,060 $176,050 $147,250 $130,390 $131,120 30
47 Nebraska $135,080 $148,230 $158,770 $153,460 $151,130 $162,710 -17
10 Nevada $210,710 $209,360 $210,690 $195,360 $144,770 $128,920 63
5 New Hampshire $226,300 $219,920 $220,480 $217,790 $218,230 $229,040 -1
35 New Jersey $169,990 $164,310 $151,750 $166,700 $156,640 $153,690 11
29 New Mexico $173,610 $167,720 $167,650 $170,570 $187,920 $175,020 -1
38 New York $164,520 $168,120 $170,300 $173,980 $164,030 $160,950 2
9 North Carolina $212,160 $225,890 $236,020 $211,370 $205,820 $187,210 13
8 North Dakota $212,380 $238,170 $202,240 $214,450 $183,600 $208,960 2
15 Ohio $197,150 $187,770 $193,430 $191,270 $186,100 $188,800 4
39 Oklahoma $156,060 $161,010 $168,820 $155,250 $147,820 $143,910 8
18 Oregon $190,690 $202,030 $192,280 $193,960 $169,110 $178,170 7
41 Pennsylvania $153,950 $138,200 $140,340 $150,620 $166,690 $164,890 -7
3 Rhode Island $254,190 $206,520 $162,070 $180,220 $183,180 $168,290 51
30 South Carolina $172,780 $192,800 $191,520 $195,350 $183,150 $169,390 2
13 South Dakota $198,170 $179,960 $160,480 $153,880 $164,590 $171,850 15
21 Tennessee $186,670 $184,760 $187,500 $176,080 $172,850 $190,380 -2
22 Texas $185,680 $172,890 $171,850 $171,870 $185,760 $186,520 0
46 Utah $138,970 $128,770 $127,480 $121,340 $112,990 $113,630 22
N/A Vermont N/A $174,090 $185,560 $180,970 $204,760 $215,410 #N/A
12 Virginia $199,870 $185,890 $177,640 $156,040 $158,780 $165,400 21
23 Washington $184,780 $187,110 $184,190 $182,990 $177,890 $194,390 -5
45 West Virginia $139,170 $160,350 $162,690 $163,610 $169,590 $177,740 -22
7 Wisconsin $213,210 $217,800 $210,300 $203,570 $178,180 $177,430 20
48 Wyoming $125,120 $143,210 $175,350 $171,340 $183,490 $176,920 -29
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Dentsply Sirona launches redesigned education site in US

November 20, 2019
Dentsply Sirona has launched its redesigned website for the US market, the company said in a press release today.
 
The company, which offers a large catalog of continuing education programs, expanded and improved its digital education offerings with one-stop access to digital training programs. Additionally, customers can purchase the products they want.
 
The Dentsply Sirona Academy provides the clinical and technical knowledge, skills, and inspiration that dental professionals need to develop themselves and their practices, the company’s statement said. This education includes more than 11,000 courses, meetings, and events, as well as 42 Education Centers. Now, they’ve expanded their online presence.
 
The new “learn” section of the new platform for the US market features a customer-focused site design with easy navigation, and easier registration process, and better search options, Dentsply Sirona said. Most importantly, clinicians will benefit from a broader selection of courses and videos.
 
Already including courses on endodontics, implants, preventative, and restorative topics, Dentsply Sirona has added courses on local anesthesia, digital dentistry, oral surgery, and practice management. The DS Academy offers more than 800 free demonstration video clips for specific procedures. It’s also a convenient way to access field experts like Drs. Sergio Kuttler, Natanya Padachey, and David Wong, who present evidence-based insights.
 
“The new site was rolled out in phases over the last few months,” said Chidam Chidambaram, senior vice president and chief digital/marketing officer at Dentsply Sirona. “We expect to continually improve the website based on ongoing testing and customer feedback. In fact, we have already made changes based on input. Our online dental courses are unrivaled in breadth and depth and, with our brand-new website, very convenient to use.”
 
The “Shop” feature allows customers to buy products using search, quick order, reorder, or they can purchase by procedure. In addition, the site offers comprehensive product information to help customers with buying decisions. 
 
“With our digital transformation initiatives, we will completely change how we approach our customers,” said CEO Don Casey. “This is all about our customers and how we can make it easy for them to serve their patients and improve their practices.”
 
For more information, visit, academy.dentsplysirona.com/en-us.
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What’s New at ALD 2020? The First “Laser 101” Full-Day Session

Coral Springs, FL – November 25, 2019 – The Academy of Laser Dentistry (ALD), recently announced its first “Lasers 101” full day educational track at the upcoming 27th annual conference and exhibition, April 2-4 at the Paradise Point Resort in San Diego.

Specifically, the “Lasers 101” track is a day pass program entitled “So You Got a Laser. Now What?” This program will take place on Saturday, April 4th from 8:00 AM to 3:00 PM. According to ALD executive director, Gail Siminovsky, CAE, “This learning track is designed to excite clinicians interested in exploring laser dentistry or those who may be on the fence about it. By taking this course, clinicians put themselves in the driver’s seat with confidence when it comes to evaluating lasers clinically and using them. It’s another example of ALD’s innovative approach to laser education”.

Here’s the “So You Got a Laser. Now What?” program at a glance:
3 expert speakers:
Michael Cataldo, CEO of Convergent Lasers. “Return on Your Laser Investment”
Dr. Juliana Barros, “Let the Light Shine: A Brighter Day at the Office”
Dr.  Shalizah Patel, “Laser Protocols: Let the Evidence Guide You”

Unbiased, scientifically relevant practical information
6 CE credits
Full access to exhibit hall
Breakfast and Lunch included
Panel discussion
Only $695 per attendee**
This program is FREE when you register for the entire ALD 2020 Meeting**

Click http://bit.ly/2pWYBl3 to register for this one-day only program. Seating is limited!

* Hotel not included
** Additional workshops and hotel not included.

The over-arching theme of ALD 2020 is “The Future is NOW: Integrating Technology into Your Practice”. The ALD 2020 experience is designed to transform careers by providing unbiased lectures and hands-on workshops on all types of lasers. Digital imaging, CAD/CAM, 3-D cone beam radiography, are all part of the curriculum, as well.

“ALD’s openly friendly and genuine approach will impress you. ALD’s discussions are lively and supportive.”  says Siminovsky.”

What else is new and exciting in the laser world?  ALD 2020 includes a  strong educational track on one of the most exciting developments in laser dentistry; photobiomodulation or PBM, a form of low-level laser therapy which has been clinically proven to heal tissue and reduce pain. The complete schedule includes the highest caliber of informative and relevant sessions that make this conference “dentistry’s laser meeting.”

Lectures: Endodontics, Periodontics, Pediatrics/TOTs, Esthetics, Medically Compromised Patients, Sleep Apnea, Pain Management, Hygiene, Financial Planning, Wealth Management, Legal Protection

Workshops: Diode Laser Basics, Advanced Diode Lasers, Endodontics, Photography, Whitening, Hygiene, Laser Certification

New Trends: 3-D Imaging, Green Dentistry. Smile Design, Caries Prevention, Periodontal Endoscopy, Adjunctive Modalities for Laser Dentistry

Early Bird Discount:

For full conference program details and registration information, visit http://bit.ly/2NOgmcK.
An early bird registration discount of $150.00 is in effect until December 31, 2019. What’s more, during the Greater New York Dental Meeting, $200.00 tuition discount coupons will be distributed during the laser courses presented by Dr. Sam Low, Dr. Mel Burchman, Dr. Gerry Ross and Dr. Laura Braswell. Each of these coupons can be combined with the early bird discount for a total savings of $350.00 for total tuition of only $895.00.

About the Academy of Laser Dentistry: 

The Academy of Laser Dentistry (ALD) is the only independent and unbiased non-profit association devoted to laser dentistry and includes clinicians, academicians and researchers in all laser wavelengths.  The Academy is devoted to clinical education, research, and the development of standards and guidelines for the safe and effective use of dental laser technology.  ALD was founded in 1993, with the merging of the International Academy of Laser Dentistry, the North American Academy of Laser Dentistry and the American Academy of Laser Dentistry.  For more information, visit www.LaserDentistry.org.

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Research and Education Evaluation of esthetic parameters related to a single implant restoration by laypeople and dentists

The Journal of Prosthetic Dentistry

Available online 19 November 2019

The Journal of Prosthetic Dentistry

Abstract

Statement of problem

Currently available assessment tools for evaluating the esthetic outcome of implant restorations consist of objective indices created for dentists. The investigation of esthetic parameters according to the patient’s perspective is lacking.

Purpose

The purpose of this observational study was to evaluate and compare the importance of different soft-tissue and restoration-related esthetic parameters for patients and clinicians.

Material and methods

A photoediting software program (Photoshop CC; Adobe Corp) was used to produce 10 photographs with modified smiles from the original photograph by altering 1 parameter of the pink esthetic score and white esthetic score (PES/WES) at a time. A total of 120 participants were recruited in the study, including 40 laypeople, 40 prosthodontists, and 40 periodontists. A total of 440 visual analog scale (VAS) values were obtained for each group to record participants’ subjective esthetic assessments of all photographs (10 modified and 1 original photograph). Repeated-measures ANOVA and post hoc mean comparison (t grouping) were used to identify whether the individual alteration on the PES and WES indices was significant for each group.

Results

For the laypeople, color (hue and value) appeared to be the most important parameter. After color, the order of importance was as follows: root convexity along with soft-tissue color and texture, level of facial mucosa, distal papilla, mesial papilla, translucency or characterization, surface texture, and tooth form. For the periodontists, color (hue and value) was also the most important parameter, but it was not separable from a cluster of other parameters: level of facial mucosa, root convexity along with soft-tissue color and texture, mesial papilla, and distal papilla. For the prosthodontists, color (hue and value) and level of facial mucosa were the most important parameters affecting esthetic assessment, followed by root convexity along with soft-tissue color and texture, mesial papilla, and distal papilla.

Conclusions

All groups graded color (hue and value) as the most important parameter affecting the esthetic outcome and the original unaltered photograph as the most esthetically pleasing image. All participants (laypeople and dental specialists) appeared to be able to perceive the same 5 parameters including color (hue and value), level of facial mucosa, mesial papilla, distal papilla, and root convexity along with soft-tissue color and texture that are negatively affecting esthetic outcomes. Except for color (hue and value), restoration-related esthetic parameters had a lesser effect on the overall esthetic assessments for all groups.
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