Bob Cohen, CDT has been actively involved in dentistry for 40 years. Currently, Bob is the president of CAP & ADT (dental Lab). He founded ADT in 1983 and today ADT is best known for implant supported restorations and esthetic dentistry.In 2010, spun from the automation component of ADT, Bob launched Custom Automated Prosthetics (CAP). Initially CAP was set up  as an outsource milling facility for dental laboratories in North America. Since that time, CAP has grown to become a digital solutions provider to the dental industry. Today CAP provides advanced digital training and support, software solutions, automated implant solutions, CAD CAM equipment and custom dental parts and proprietary digital software solutions.

Bob Cohen, CDT

	Like many new technologies introduced into the dental market, guided implant surgery has been slow to catch on. The reasons are many: cost, learning curve of complex software and time to do the virtual plan, to name a few. More recently, placing implants using a surgical guide has become much more popular. We now have faster, more powerful computers, better software and an increased number of CBCT scanners in dental offices. As a result, guided implant placement is more viable and economically feasible than ever before.   

Recently, 3Shape launched a new software module called Implant Studio. This end-to-end solution is built for guided surgery, merging surface scans and CBCT (or CT) scans. Subsequent digital CAD design of the final restoration follows by planning implant placement. Utilizing the combination of the design of the final restoration, the CBCT and surface scans enable a best-in-class plan. This top-down digital workflow is both simple and precise and eliminates the need for manufacturing an appliance prior to and solely for use for the CBCT scan.  

Related reading: Smoothing out CAD/CAM with software

	Once the implant placement plan is accepted, there is a quick-and-easy digital guide design step that creates an STL file for milling or 3D printing surgical guides. This software can be purchased as a standalone planning solution or added to an existing 3Shape dongle. One of the really terrific things about Implant Studio is that it puts the planning in the hands of dental labs. This helps lab owners build new relationships and customers. An additional inclusion in the software is a sign-off process that puts the liability of the plan on the surgeon through a design approval process. 

	Click the next button to go step by step ... 

	01 To begin implant planning, one uploads a CBCT scan, as well as a surface scan, into the Implant Studio software. Next, the implant locations and other info are added to a Virtual Rx (

	When treating the posterior mandible, one of the initial steps includes identifying and marking the mandibular nerve canal and mental foramen (

	02 Once the Rx is complete, the final restoration is designed using an abbreviated set of tools and functions found in the existing 

 Dental System CAD software. Once the design of the restoration is complete (

), an outline of the final restoration appears in the CBCT views throughout the planning (

	03 Next, through a dropdown box, one selects the brand, type, diameter and length of implant to be used in each implant site (

	Intuitively, the software places the implants extremely close to the final desired location through smart placement using the restoration design previously completed. The software currently has a 2 mm safety zone around the implant (

	04 The planning stage offers tools that are very simple to use. The implant location can be adjusted or rotated, the implant can easily be lengthened or shortened and/or the implant type can be changed easily mid-design. Additional tools include the ability to group implants together to keep them exactly parallel to one another (

Fig. 8 Change in color of implant when too close to nerve

	This is very helpful for overdenture cases where direct-to-implant overdenture retention abutments are planned. Having these implants parallel to one another reduces frequency of clinical attachment maintenance. The software changes the color of the implant while planning from green to red if the placement is too close to an anatomic feature that should not be impinged upon (

) to help keep the plan and subsequent surgery safe and trouble-free. 

	05 Once the plan is finalized, we utilize a screen-sharing application called Teamviewer, which enables the dentist to see our plan screen live from any PC (or Mac). In fact, the dentists can also control the screen using their mouse. Once the dentist is satisfied with the plan, there is an approval screen (

) that eliminates the laboratory liability. Once the dentist agrees and checks the “Approved Plan” box, the plan is permanently locked and the implant locations can no longer be altered.

 procedure is designing the surgical guide. To do so, using the mouse, you simply draw a line on the surface scan outlining the periphery of the guide (

). Once you connect the end of the outline to the beginning, you can adjust any part of the design except the hole locations for the drill guides. Keep in mind the hole placements were locked at the end of the plan stage. With a click of the mouse, the guide appears on the virtual model. 

	07 There are a few more features one should include to finalize the guide (

). You can add a patient name or ID. As a last step, place a couple of square or rectangular holes through the occlusal surface of the guide. This serves as a view box for the dentist to check for complete seating of the guide prior to starting the placement procedure. 

	08 Another important benefit of working with Implant Studio is that it is fully integrated with the 3Shape Dental System CAD software. This enables you to take the planned implant positions from Implant Studio into Dental System and design and fabricate restorations prior to surgery. Basically, you are working with 100 percent consistent data across the 3Shape software platform. This is an ideal solution for “teeth-in-a-day” workflow. 3Shape has made it possible to fabricate and deliver provisionals and or final prosthetics at the time of stage one surgery.

	09 Implant Studio outputs an STL file for the surgical guide. For manufacturing, one can use a five-axis mill and clear PMMA disc or a 3D printer. We use both manufacturing technologies with no significant difference in the end product. For milling, we use the Roland DWX-50 and the new 

 with the clear bio-compatible MED610 print material. Once the guides are milled or printed, the final step is bonding in the titanium drill guides (

). This is achieved using Multilink Automix adhesive (Ivoclar Vivadent) and following manufacturers recommendations for technique. The Implant Studio software provides the part numbers for guide sleeves produced by Steco of Germany and sold in North America by CAP. 

	In conclusion, guided surgery eliminates questions and potential problems with regard to implant placement. It results in superior placement more routinely and often shortens the surgical procedure. This, in conjunction with making guided surgery an offer from your laboratory, will result in opening doors to new customers and help you grow your business. Lastly, becoming well-versed in Implant Studio is likely much easier than you may anticipate. Not to mention, if all implants were placed using a guided surgical protocol, the patient would receive restorations with fewer compromises.

Articles

Bob Cohen, CDT, writes a step-by-step technique showing how 3Shape's Implant Module for Dental System can be used to plan implants and create surgical guides.

Step-by-step: How to digitally plan implants and design surgical guides

	Through the accelerated advancement of CAD/CAM technology and material science, dentists have several new, high strength all-ceramic materials in the indirect portfolio to choose from. The recent dramatic increase in the cost of gold in combination with current economic conditions is accelerating demand for these new products. Dentists are prescribing these new metal-free all-ceramic restorations at a rapidly accelerating pace. As a result, dental technicians are faced with the need to develop new skills for manufacturing as well as finishing processes for these new advanced, high strength all-ceramic materials. In this article, I share recent developments in rotary instruments that facilitate trimming sintered zirconia as well as lithium disilicate.

	Historically, technicians have been trimming, cutting or grinding feldspathic ceramic materials. These materials have a victor hardness of about 6.4 GPa. The newer, higher strength lithium disilicate and post sintered zirconia materials have a victor hardness of about 12.75 GPa. As a result, it is necessary to develop new protocols and rotary instruments that cut these harder materials efficiently while simultaneously keeping heat transfer as low as possible. We have been working with Wagner Precision Rotary Instruments to develop a new line of rotary products that meet the challenges of today’s harder all-ceramic materials.

	Sintered zirconia is not a good conductor of heat. When friction from grinding occurs the heat does not transfer through the material. When trimming the material the area that is in contact with the rotary instrument becomes hot, while the ceramic adjacent to the trimmed area remains comparatively cool. Post sintered zirconia, like most materials, expands under heat. This localized temperature differentiation can cause failure or cracking. Finishing post sintered zirconia, both full contour and frameworks, should be performed using irrigation and selecting rotaries that minimize heat transfer.

 We first check for fit. If internal adjustments are necessary we will use Red Quickcheck Indicator Spray fit check spray. Observation of areas of interference can be adjusted with either a FG1C or an FG2E 

 Zirconia margins can be thinned nicely using a friction grip fine diamond at low highspeed with irrigation and a light touch. For thinning post sintered margins on zirconia frameworks we use a fine football-shaped FG5C tool. This will aid in thinning out chamfer or shoulder areas while simultaneously thinning out the margins. For full-contour zirconia, using a straight or slightly tapered diamond FG5C will result in a beautiful knife edge margin and aid in providing a proper emergence profile 

 Use a FG4A to adjust occlusal contacts. Refine proximal contacts with an FG1C.

 Adding anatomical detail to post sintered zirconia is perhaps the most difficult rotary problem in the finishing process. Great care should be taken in the CAD stage to ensure proper occlusal contacts and morphology. This can be achieved with most CAD programs and a good anatomic library. If there are small morphological alterations needed, use an FG3A 

. Microscopic marginal integrity can be evaluated in 

 Studies show the surface wear of zirconia to opposing natural dentition is less than feldspathic porcelain. Tests were performed with polished occlusal zirconia surfaces as well as unpolished occlusal surfaces. The conclusion of these studies was favorable only on the polished zirconia surface. Before stain and glaze it is imperative to polish zirconia with the RedBerry™ and BlueBerry™ wheels 

 Last is a light sandblast to the outer surface with 50 micron aluminum oxide at 30 lbs., before stain and glaze. Wagner Rotary Instruments also has developed an adjustment kit for chairside adjustment and intraoral polishing.

	In accordance with protocol developed by Ivoclar Vivadent grinding on lithium disilicate (e.max™) should be performed with irrigation. A step by step protocol for finishing lithium disilicate press includes different rotaries.

 Check the fit. Generally, the restoration will drop on. If there is interference in seating, an FG1D highspeed diamond tool is used internally to remove any interfering material. If the interference is within .75 mm of the margin I recommend using a small knife edge BlueBerry™ at a very slow speed. Unlike zirconia, lithium disilicate margins are far more delicate and can possibly chip.

 Once fit, remove the sprue with a Large DiaCool wheel 

. DiaCool is specifically designed to provide bulk reduction with minimal heat transfer.

 Thin or finalize the crown margin with a diamond impregnated coarse BlueBerry™ 

. It is critical to use an instrument that smooths as it cuts through the ceramic. Again, grinding with a diamond or cutting with a carbide likely will result in chipping and/or fracturing the margin. The RedBerry™ and BlueBerry™ combination reduces tool chatter, vibration and chipping.

 Final interproximal contact adjustments should be performed on a solid cast. Using articulating paper we can check for premature surface contacts.

 Once you transfer markings to the restoration, remove any excess material with an FG4A diamond tool. The addition of posterior occlusal anatomical features can be accomplished using a FG169L. When redefining anatomical morphology, work from the outer perimeter of the occlusal surface to the fossa. This reduces the risk of fracturing the lithium disilicate. Hold the tool at a 45° angle and perpendicular to the anatomical feature being cut. Use a combination of tools for labial surface anatomy. For anterior restorations, develop vertical surface anatomy with a FG1C followed by a FG3A.

 Before stain and glaze, smooth remaining surface imperfections and scratches with a BlueBerry™.

 Final High Shine polishing is accomplished with Wagner’s 26 mm knife edge Golden eagle #641.

	For videos on finishing these materials visit 

 Through the accelerated advancement of CAD/CAM technology and material science, dentists have several new, high strength all-ceramic materials in the indirect portfolio to choose from. The recent dramatic increase in the cost of gold in combination with current economic conditions is accelerating demand for these new products. Dentists are prescribing these new metal-free all-ceramic restorations at a rapidly accelerating pace.