Lithium Disilicate: A Viable Replacement for Traditional PFM’sby John C. Cranham DDs

Layered Lithium DisilicateWhile some strength is sacrificed when utilizing lithiumdisilicate as a core and then layering porcelain onto the facialand occlusal surfaces, unbelievably beautiful esthetics can beachieved when doing so. Additionally, this material is nowbeing pressed and milled at less then .5 mm in thicknesswhen fabricating porcelain veneers. The bottom line is thatthis material can be used to fabricate beautiful restorationsin all sextants of the mouth. In the posterior segments,monolithic crowns can be fabricated for optimum strengthwith esthetics that greatly exceeds a traditional PFm. In theanterior segments, the cores can be cut back and porcelaincan be layered to create the ideal gradients of color.

Case ReportFigures 1-4 illustrate a 50 year old woman who had beenrestored unsuccessfully with porcelain fused to metalrestorations. she presented with a Class II malocclusion andan anterior open bite. Cone beam computerized tomographyin conjunction with joint vibration analysis and a traditionalTm joint examination revealed healthy, stable Tm joints. shehad moderate localized periodontitis (5-6 mm pocketing) inher ul, ll and lR sextants. she was also extremely unhappy

As a new dentist in 1988, choosing arestorative material was relatively simple.Direct restorations involved compositeresin for anterior teeth and amalgam forposterior teeth. Indirect restorativematerials involved gold and porcelainfused to metal. While these materials

have served the population for the better part of fifty years,many patients found these materials falling short esthetically.By the mid 1990’s, numerous manufacturers responded witha variety of all-ceramic options. These materials required theuse of fourth and fifth generation bonding agents with resincements. While they were unbelievable beautiful, they hadthe potential to be technique sensitive and many times theywould fall short functionally.

As time has gone by, the general population has continuedto put pressure on the profession to create lifelikerestorations that could have enough longevity to justify thefee. While several materials have hit the market in the last fewyears, recent studies suggest that lithium disilicate has thestrength, durability and esthetics that make it the logicalreplacement to the time tested porcelain fused tometal crown.

Monolithic Lithium Disilicatelithium disilicate can be fabricated by milling or pressing.While studies suggest that the pressed variety is slightlystronger, this material fabricated in a full contour form(monolithic) is extremely strong. A clinical trial by Dr. DennisFasbinder looked at the survival rate of 62 CAD/CAm crownsdelivered with three different cements. After three years offollow-up examinations, the crowns showed no chippingor fracture.

Additionally, researchers at New York university performedresearch utilizing mouth motion simulators. The machineallows the scientists to increase the loading and chewingcycles on the various materials tested. monolithic IPs e.maxsurvived over one million cycles at 1000 Newtons of force,very similar to porcelain fused to metal crowns. This researchbodes well for our ability to trust this form of lithium disilicateas the logical replacement for dentistry’s gold standard.

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Figure 3 Figure 4

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combining those elements with the utilization of acontemporary ceramic, predictability was ensured. Whilenumerous ceramic options are currently on the market, it is thisauthor’s opinion that lithium disilicate is a logical replacementfor traditional PFm’s.

special thanks to Albert Konikoff DDs (periodontist), Carl RoyDDs (orthodontist), the oral surgical Team at Portsmouth NavalHospital, and the team (Jeff stubblefield - Technical manager,mike Felgenhauer CDT - senior Ceramist) at DAl signatureRestorations laboratory, Peoria, Il.

References:Della Bona A, Kelly JR. The clinical success of all-ceramic restorations. JADA.2008;139:8s-13s.

Fabianelli A, Goracci C, Bertelli e, Davidson Cl, Ferrari m. A clinical trial of empressII porcelain inlays luted to vital teeth with a dual-curing adhesive system and a self-curing resin cement. J Adhes Dent. 2006;8(6):427-431.

Ritter RG, Rego NA. material considerations for using lithium disilicate as a thinveneer option. J Cosmet Dent. 2009;25(3):111-17.

Guess PC, Zavanelli R, silva NR, Thompson VP. Clinically relevant testing of dentalporcelains for fatigue and durability with an innovative mouth motion simulator.Presented at 39th Annual session of the American Academy of FixedProsthodontics, February 2009, Chicago, Il.

esquivel-upshaw J, Rose W, olivera eR, Anusavice KJ. In vivo analysis of enamel wearagainst ceramic materials. J Dent Res. 2009; 88(A): Abstract #1009.

Kheradmandan s, Koutayas so, Bernhard m, strub JR. Fracture strength of fourdifferent types of anterior 3-unit bridges after thermo-mechanical fatigue in thedual-axis chewing simulator. J oral Rehabil. 2001;28(4):361-369.

About the author: Dr. John C. Cranham has a contemporary dental practice inChesapeake, Virginia, focusing on cosmetic, restorative and implant services. In1999, Dr. Cranham founded Cranham Dental seminars which, in February of 2008,merged with the Dawson Academy. He is a partner and the acting clinical directorof the Dawson Academy where he is involved with many of the lecture and hands-on courses within the curriculum. As an active educator, he has provided over 750days of continuing education for dental professionals throughout the world.

Dr. Cranham works closely with our DAl signature Restorations laboratory. DAlsignature Restorations laboratory is a division of DAl dedicated to providing highperformance, highly esthetic restorative services to meet even the most demandingpatient’s esthetic requirements. our commitment to extensive training withinstitutions such as the Dawson Academy and the spear Institute provides thenecessary technical disciplines to ensure restorations that are perfect in everyaspect – color, shape and design.

with the esthetics of the existing restorations. she felt theywere too big and bulky, and desired a brighter more naturallooking smile. she especially did not like the metalappearance at the gingival margin of several of herrestorations. she also expressed interest in improving herfacial appearance.

The goal of this treatment plan was to create a maintainablehealthy periodontal environment, improve her facialappearance, create optimum occlusal stability and restorethe teeth back to a “normal size. ” This was achieved throughan interdisciplinary process that involved the periodontist,the orthodontist, the orthognathic surgeon, and therestorative dentist. The following is the treatment plan thattranspired over a 24 month period.

Phase One: splint therapy was utilized to achieve condylarseating and to create occlusal stability. Additionally,periodontal therapy included scaling and root planing. Asurgical procedure was performed to remove thepigmentation above the free gingival margin of teeth #8-9,and pocket elimination surgery was done in the ul, ll andlR sextants.

Phase Two: A diagnostic wax-up was completed to createideal tooth size and morphology of every tooth in thedentition. The upper and lower arches were then preparedand single tooth provisional restorations were placed withpermanent cement. This then allowed the orthodontist toproperly place his brackets so the ideal arch form could becreated. After approximately six months of orthodontictreatment, the patient was prepared for a two jaworthognathic surgical procedure. The upper and lower jawswere brought forward to create balanced facial esthetics andan ideal Class 1 occlusion. orthodontics were then utilizedpost-surgically to fine tune the position of the teeth prior tothe restorative phase.

Phase Three: After ortho-orthognathic surgery, a finalocclusal analysis and wax-up was completed. monolithiclithium disilicate restorations with 2 mm of occlusal coveragewere used on the molars. From second bicuspid to secondbicuspid, microlayering was utilized on the facial surfaces toimprove the esthetics. All of the restorations were bonded toplace using a self-etching resin cement. Figures 5-8 illustratethe final result.

ConclusionWe are fortunate to be practicing dentistry in such anamazing time. We have more information about esthetics,solutions to complex functional problems, andcontemporary restorative materials then ever before. Byfollowing the treatment planning protocols espoused by theDawson Academy philosophy, working with a greatinterdisciplinary team (a periodontist, an orthodontist, anorthognathic surgeon and a first class dental laboratory), and

Figure 6

Figure 7 Figure 8

Figure 5

IPS e.max® Monolithic Lithium DisilicateThe Premium Alternative to Gold PFm’s

1000 N*

350 N*

IPS e.maxlithium

disilicate(monolithic)

zirconia(veneered)

3 IPS e.max Restorations to Choose From

IPS e.max CADIPs e.max CAD is milled usingenhanced software with the e4Dlabworks system from D4DTechnologies and the sirona inlabmCXl milling machines at DAl. usingCAD design with CAm milling

technology, we are able to improve the precision andconsistency of contacts, occlusion and morphology whilereducing labor time and costs to our customers. With aflexural strength of 360 mPa’s, IPs e.max CAD is indicatedfor single unit anterior/posterior crowns andinlays/onlays...$99/unit

IPS e.max CAD MicroLayeredIPs e.max CAD microlayered is aCAD/CAm monolithic IPs e.maxcrown with a minimum amount ofmicrolayering to enhance the vitalityand lifelike appearance in theanterior...$139/unit

IPS e.max PressIPs e.max Press is thesame lithium disilicatematerial in a glass-ceramic ingot format.using press technology,IPs e.max Press offers aflexural strength of 400

mPa’s presenting greater strength for 3-unit anteriorbridges, ultra-thin veneers and restorations with minimumpreparation dimensions...$175/unit

Preparation RequirementsFull coverage crowns require a chamfer or a roundedshoulder margin with a width of approximately 1 mm.Facial reduction is 1.5 - 2 mm; 1 - 1.5 mm lingual contactclearance, incisal reduction is 1.5 – 2.0 mm with roundedinternal line angles.

CementationThe high strength of IPs e.max offersdentists a choice to adhesively bondor conventionally cement theirrestorations. Crowns and bridgescan be cemented with yourpreferred cement. Inlays, onlays andveneers should be bonded.

With metal prices continually on the rise, many of our customershave been inquiring about viable alternatives to metal basedrestorations that can offer comparable strength, reliability andpredictable flat-rate pricing. DAl offers several gold-free optionsthat are worthy of consideration, including our DAl eZ estheticZirconia at $139/unit, BruxZir solid Zirconia at $99/unit and ourcomplete line of IPs e.max restorations.

We highly recommend you consider IPs e.max from Ivoclar as it is aversatile system that provides you with a complete range ofrestorations to meet all of your patient demands for minimallyinvasive dentistry.

IndicationsIPs e.max lithium disilicate is a glass ceramic that has optimizedtranslucency, durability and strength for full anatomicalrestorations. Available both as a pressed ceramic (IPs e.max Press)and as a CAD/CAm milled restoration (IPs e.max CAD), IPs e.max isindicated for anterior/posterior single crowns, 3-unit anteriorbridgework (bicuspid forward), ultra-thin veneers and inlays/onlays.

Outstanding Esthetics with Maximum StrengthIPs e.max lithium disilicate is a high strength ceramic with 360-400mPa’s of flexural strength. When fabricated to a full-contour or in amonolithic state, lithium disilicate is an extremely durable material.Failures (fractures/chipping) in zirconia or PFm restorations areoftentime the result of a very weak 90 mPa layered porcelain surfacematerial having chewing forces exerted upon it. With monolithic(lithium disilicate homogenous throughout the entire restoration),the work of the mastication is being done on a 360-400 mPamaterial…making this restoration the most robust ceramic systemtested to date.*

Material Survival with Cyclic Fatigue Testing

*mouth motion Fatigue and Durability study: Petra C Guess, Ricardo Zavanelli, Nelson silva and Van P Thompson, NYu, June 2009

4-Year Clinical Performance, The Dental Advisor, June 2010 Volume 27, No. 05reported only 2.5 % of the 236 restorations tracked over four years exhibitedchipping and only 0.5% had fractured or needed replacement. 94% of theIPs e.max restorations received a five or excellent rating, demonstratingsuperior esthetic quality. IPs e.max Press is highly recommended by TheDental Advisor.

Axel Kufner, MDTCeramics, Crown & Bridge Manager

Product Profile - Fixed Restorations

Veneered Zirconia Systems• 90% Failure Rate at 350N and 100,000 cycles

IPS e.max CAD Lithium Disilicate• 0% Failure 1,000 N and 1,000,000 cylces• No chips, cracks or fractures!

New! Vericore® CAD/CAM Abutments with Implant Prosthetic Package Pricing

Noble PFM with Vericore AbutmentTitanium Abutment.....$499*

Vericore Zirconia Crown with Vericore Titanium orZirconia Abutment

Titanium Abutment.....$519*

Zirconia Abutment......$549*

IPS e.max CAD or BruxZir Crown with Vericore Titanium or Zirconia Abutment

Titanium Abutment.....$459*

Zirconia Abutment......$489*

DAl is proud to represent theDawson Academy as anAccredited Dawson laboratory.This designation represents thehighest level of comprehensive,full service laboratory supportavailable to dentistry. TheDawson Academy has alignedwith us at DAl to offer you ascholarship that will reimburse

you for the cost of one of their Core Curriculum lecturecourses or offset the cost of one of the hands-on courses. Byprescribing $16,500 in new or incremental casework withDAl, you will qualify for a laboratory credit of $1,695 to applytowards your tuition. Call Ambur Garza at 1-800-227-4142 orvisit www.dentalartslab.com for more details or to get theDawson Academy education schedule for 2011.

Earn a Dawson Academy Scholarship from DAL!

Core Curriculum: Lecture Courses• Functional occlusion - From TmJ to smile Designmay 12-14, 2011

• Achieving Predictable esthetic ResultsJune 23-25, 2011

Core Curriculum: Hands-On for Dentists• Comprehensive examination and Recordsmay 12-14, 2011 • september 22-24, 2011

• Treatment Planning Functional esthetic excellenceoctober 27-29, 2011

save $200 on any Dawson Academy lecture or Hands-on Course being held in Chicago in 2011! To register for a Dawson Academy course, visit www.TheDawsonAcademy.com or call the Dawson Academy at 1-800-952-2178. simply mention DAl when you register to receive your discount!

2011 Dawson Academy Courses in Chicago

All DAL Products Are Made in the USA!DAl is proud to provide you with 100% American made products and services. We do not outsource any of our products to foreign laboratories. We manufacture all of our products using only premium

FDA approved materials. Identalloy stickers are available.

DAL and Vericore, a division of Whip Mix Corporation, have teamed up to bring you the latest in high quality, high strength zirconia and titanium implant custom milled abutments and premium implant prosthetic package pricing.

Vericore Titanium Abutments are available forten major implant systems.• 3i Certain• 3i Hexed• Astra Tech Implant System• Branemark System• Endopore External Hex• NobelReplace• Southern Hexed• Southern Tri-Lobe• Straumann• Zimmer

Vericore Zirconia Abutments available in 7 natural shades.* Price includes soft tissue model, analog, labor, abutment screw and final CAD/CAM titanium

or zirconia abutment with crown. $15 round-trip overnight shipping is additional.

locations in Peoria, Il • lincolnshire, Il • st. louis, mo • springfield, Il • Galesburg, Il • Aurora, Il1.800.227.4142

Valplast®

The ultimate Partial solution

Patients with metal clasp partial dentures often express that theyfeel self-conscious about smiling, conversing and even enjoyinga meal. Not anymore with the Valplast Flexible Partial Denturefrom DAl.

With Valplast, you can now create metal-free, lightweight flexiblepartial dentures that provide a natural tissue blend effect withtranslucency that picks up the patient’s natural tissue tone. Thetranslucency is combined with a simulation of natural bloodvessels that readily adapts to a variety of natural tissue shades.Additionally, each Valplast partial is designed to follow thepattern of natural tissue formations with thin clasp designs,making the restoration virtually unnoticeable when worn.

Material PropertiesValplast is a pressure-injected, flexible denture base resin, abiocompatible nylon thermoplastic that is available in three basicshades - medium pink, light pink and meharry ethnic.

Valplast Benefits• Patient Comfort - very thin and lightweight for more sensation• esthetic and Biocompatible• No tooth or tissue preparation required• Durability - Valplast provides exceptional comprehensive,

impact and bending strength• Will not stain or absorb odor

Valplast IndicationsValplast can be used whenever a partial denture is indicated.There are three basic design options:

*Includes articulation, framework, setup, Kenson teeth and process/finish. Portrait IPN/Blueline teeth and shipping are additional.

Valplast Bilateral

Partial Denture...$257*

Valplast Permanent Flipper...$216*

Combination Valplast with

Vitallium 2000 Plus...$423*

What to Send to the Laboratory• Full models - master with opposing Arch• Bite Registration• Tooth shade/Valplast shade

Insertion TechniqueImmediately prior to insertion in the patient’smouth, immerse the Valplast restoration in veryhot tap water. leave the partial in the water forabout one minute. Remove the partial from thewater and allow to cool just to the point where itcan be tolerated by the patient. The hot watertreatment allows for a final adaptation with thenatural tissues in the mouth.

Adjustments/Polishing/Patient Careeach Valplast partial comes with a DAlAdjustment/Polishing/Patient Care Kit free ofcharge. This kit contains detailed instructions aswell as the necessary green silicone carbideabrasive, a brown rubber wheel and a Val-Cleandenture cleaner packet for the patient.

Add To/Reline ProcedureYes, you can add to a Valplast partial. However, itmust be sent to us for add-ons. simply pull theValplast in a pickup impression and include theshade. For relines, provide the laboratory with anew impression and opposing model with a biteregistration.

Sheryl WardFlexible Partial Denture Manager

Product Profile - Removable Prosthetics

Dental Arts Laboratories, Inc.241 NE Perry Avenue, Peoria, IL 61603-3625www.dentalartslab.com • 1.800.227.4142

presorted

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U.s. postAGe pAId

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perMIt No. 999DeNTAL ArTS LABorATorIeS, INC.241 NE Perry Avenue, Peoria, IL 61603-3625

PLUS:

IPS e.max® Monolithic Lithium Disilicate

The Premium Alternative to Gold

Valplast®

The ultimate Partial solution

Building Your Practicewith Vericore® Implant

Prosthetic Packages

3Great Reasons toPrescribe monolithic Restorations from DAL!

$99/unit

BruxZir™ Solid ZirconiaCrowns & Bridgework

IPS e.max® CADCrowns

$99/unit

IPS e.max® PressCrowns & Bridgework$175/unit

see inside for more details!