March 2013, Volume 9, Issue 3
Published by AEGIS Communications
Key Steps to Restorative Outcomes
Patient assessment, treatment planning, and plan execution checklists to help practitioners get it right the first time
Patient evaluation, treatment planning, and restoration design and fabrication have been greatly impacted by technology, such as digital impressions, chairside or off site CAD/CAM restorations, and “smile design.” However, human interaction—communication, visualization, planning, and reassessing—is at the core of patient care. Practitioners and patients still need to have a clear, mutual understanding of the objectives of treatment and how the components of the treatment plan will be created and accomplished to meet those goals. Most of all, the practitioner needs to execute these components to achieve a predictably successful outcome and ensure patient satisfaction. This means balancing factors such as sequence of treatment, dental occlusion, restoration design and materials, plus patient-driven requirements such as cost, convenience, and timetable. To accomplish their objectives, many practitioners find their personal checkpoints—either lengthy formal lists or an essential number of steps—indispensable.
Patient Examination Take Aways
“Treatment planning begins with determining what the patient wants. The exam process is important, but you really have to focus on their chief complaint,” says John Weston, DDS, a La Jolla, California, private practitioner who stresses the importance of building the patient’s trust and confidence to ultimate treatment plan acceptance. “If you don’t address the reason they came in, they’re not likely to follow through with anything.”
Some cases are simple, requiring little more than removal of decay and placement of a tooth-colored filling or a crown that can be milled chairside or sent out to a laboratory. Others are more extensive, either for esthetic or functional rehabilitation. Most of what a dentist needs to know can be determined by listening to the patient carefully and completing a thorough examination. Richard Rosenblatt, DMD, regards that first visit as an opportunity to size up the patient. “When a patient comes in, I’ll do a good thorough examination including x-rays and a full-mouth series of photos.” The first concern of the Lake Forest, Illinois, private practitioner is the health and condition of their teeth. Was past work done well? Is the shape/morphology adequate? What is the extent of decay? What about wear patterns? Are there signs of initial, moderate, or extreme bruxism, extreme wear? Then, he says, he and the patient view the pictures together, “co-diagnose” their concerns, and determine an approach to treatment.
During the examination, Joseph R. Greenberg, DMD, who is Clinical Professor, Department of Restorative Dentistry, Kornberg School of Dentistry, Temple University, and Clinical Professor, Department of Periodontics, University of Pennsylvania School of Dental Medicine, Philadelphia, Pennsylvania, pays special attention to signs that may indicate a patient is high risk due to functional issues such as apparent heavy bruxism or a history of broken dental work. “High-risk patients may require more abutment support in a given area for stability than a low-risk patient, and the occlusal design—for example, the width of the occlusal table—must be considered. We have to pay attention to this ‘patient type’ and design our restorations accordingly.”
Patrick Bever, an Advanced CAD/CAM dental technician at Apex Dental Milling, in Ann Arbor, Michigan, and Chris Brown, BSEE, who is a manager there, are on the lookout for the 10% to 20% of cases requiring special considerations in materials and design. Relying on their broad perspective (based on the sheer volume of cases they handle while working with some 100 laboratories each serving five to 10 dental practices), their trouble-shooting suggestions are usually appreciated by their clients, mainly laboratories, because, as Brown points out, “nobody wants to do a case twice.
“We’re always trying to look for clues that tell us we need to do something a little bit different, for example, when the case is presenting a dark stump shade or is in cross-bite.” Information, he says, is key. “Doctors who are aware of such exceptions know when to gather that extra information—eg, that cross-bite reference, stump shade, or open bite.”
Elements of Treatment Planning
Creating and executing a treatment plan hinges on practice specialties and resources, including equipment, staff, and access to services. For example, because Weston’s practice is multi-specialty, patients can quickly be seen by a periodontist, if there are gum issues, or an orthodontist, if treatment goals would be enhanced by tooth movement; and Rosenblatt, who offers CAD/CAM chairside restorations, can send patients home with well-fitting temporaries or even final restorations on the very day they present.
The Art and Science of Esthetic Assessment
Greenberg tries to instill in his students the importance of examination, diagnosis, and treatment planning for which, he says, dentists are “usually poorly compensated.” Because dentists are by necessity focused on making a living, he and Meredith C. Bogert, DMD, developed seven “check points” for dentofacial examination, diagnosis, and treatment planning for Advanced Education in General Dentistry residents.
These check points, which were featured in Compendium of Continuing Education in Dentistry,1 are as follows:
(DM=FM): Widely considered the most important diagnostic element, the highest priority is attempting to align the maxillary dental midline (DM) to the patient’s facial midline (FM). Students are shown how to find the facial midline (FM) with the patient watching, by placing a long piece of dental floss from chin to forehead, getting the patient involved in this important determination.
(DV=FV): Once the dental and facial midline are aligned, the next goal is to have the dental vertical axis (DV) parallel the facial vertical axis (FV).
(DH=FH): The dental horizontal (DH) should align with the facial horizontal (FH). It should be perpendicular to FV. The incisal edge line (incisal plane) of the maxillary anterior dental composition and the buccal cusp tips of any posterior teeth on display in wide smile, should parallel the facial horizontal plane.
At this point, clinicians should verify that both maxillary central incisors are equal in position, symmetry, color/shade, and are located at the facial midline/facial vertical axis/facial horizontal. They should make sure that the relative tooth proportions and specifications follow the rules of biometrics.2
Now clinicians should check to see if the incisal edge line of the maxillary anterior teeth follows the superior contour edge of the lower lip, if the latter is symmetrical to FH.
The clinician should ascertain whether the incisal edge line forms an “attractive” (convex, “gull-wing,” or straight) edge pattern—never concave! This is also the time to evaluate for “high” (greater than 4 mm of gingival display), “normal” (0 to 4 mm gingival display), or “low” (no gingival display) lipline character of the patient’s smile.
The final item deals with evaluating the patient’s profile as well as speech/phonetics. The “F” and “V” sounds can be used to determine correct maxillary incisal edge position. The “S” sound has been described to test for adequate freeway space when an alteration in occlusal vertical dimension is being considered.
The purpose of these items, maintain Greenberg and Bogert, is “to use an organized sequence of physical parameters to recognize major elements of dental composition and function, and place these elements in a symmetrical relationship within the facial complex, to create a harmonious integration of displayed dental components with facial structures that patients and dentists will recognize as pleasing and attractive.”1 As Greenberg and Bogert emphasize, this checklist is a preliminary approach that prompts the clinician to broaden his or her vision from purely a dental/periodontal focus to one that encompasses lip, cheek, and tongue configurations; smile; facial features; and related planes of symmetry.1
While Weston uses a formal checklist to methodically execute the many components of his finalized treatment plan, the plan he creates for patients with healthy gums is based largely on what he calls a “smile design workup” that enables patients to understand exactly what changes will be made and how they will look in their own mouths. This starts with a digital smile design (DSD), which basically shows an outline of the teeth, “a kind of stick drawing,” and basic measurements, including width-to-length ratios and how the patient’s midline, length of teeth, and angulation relate to the face. He then creates an in-the-mouth “trial smile” or prototype to show the improvements planned, length changes, etc. This design is transferred to the patient’s mouth—either directly by creating a freehand mockup of composite material or using an impression of a laboratory-fabricated wax-up. He credits Brazilian dentist Christian Coachman for introducing this concept to his treatment planning.
After patients see the mockup in their mouth and approve it, Weston broaches the topic of steps that need to be taken to achieve the desired end result. “If it’s tissue movement, you have to decide if you’re going to use a laser to do that or see a periodontist. If there is severe rotation, crowding, or spaces it’s always more conservative to align the teeth before restoring to save more tooth structure,” he says. This is also the time to consider the patient’s budget and timetable. For some patients, cost is a major issue. Whether it involves a single tooth or full-mouth smile transformation, Weston emphasizes the importance of developing an acceptable treatment plan that will maximize esthetics and function. When cost is an issue, he says, direct materials such as composite can be more convenient and less expensive than porcelain. “A direct restoration might not last as long as porcelain, but it will last well and look good at half the price.”
For patients who can’t afford to restore more than one or two teeth, despite overall signs of wear on teeth and restorations, Rosenblatt may offer an interim solution. “For them, I can treat the decay problem for the short term and use my CAD/CAM to re-create a restoration that will conform to their existing dentition.”
Material Selection and Occlusion
Weston emphasizes the importance of occlusion— especially in larger cases—and relies upon a centric relation occlusion scheme. “No matter what kind of restorations or crown, we can always go back to a repeatable bite record that is guided by skeletal anatomy, not teeth.”
While Greenberg’s mentor, Leonard Abrams, used the phrase “the occlusal material is immaterial” if designed according to sound principles, Greenberg hastens to add that most important among those principles is patient selection—that is, choosing a material based on functional needs of the patient. “The fact of the matter is, not every material can stand up to the abuse imposed by functional considerations such as bruxism, cross-bites, and large muscular jaws.”
Weston selects a material based on what needs to be done to the tooth. “For me, material selection is dictated by the clinical situation and based on tooth removal parameters, esthetic parameters, and how much you’re changing the tooth physically.” Some materials, he says, require preparation that may not make sense for the patient or scenario. “For example, you don’t want to choose a material that requires you to remove a substantial amount of healthy tooth structure just to make a small color change or minor shape repositioning.”
As Brown points out, “There’s a certain assumption that everyone is aware of what materials are indicated for what, but choices should be based on function as well as esthetics.” Because, as Bever explains, there are now more choices and more ways to do things than ever before, they make an effort to educate their laboratory customers, who in turn, can then educate their clients as to why something might be a better choice. Bever also tries to make clients aware of other considerations—both esthetic and functional—that should take the patient’s age and future treatment into account. “With young patients, they shouldn’t be too aggressive with how they are restoring something in the short term; also to be factored in is translucency.”
First Things First—Importance of Sequence
The fundamental aspects of correct sequencing include starting treatment with corrected tooth position, completed periodontal treatment, and a healthy plaque/biofilm. As Greenberg warns, untreated gum infection can undo an otherwise carefully planned crown or implant, potentially causing gum recession, instability, and difficulty in impression making.
When the treatment day comes, Weston depends on his trusty checklist (see sidebar) to prevent problems from improper sequence during the preparation phase, including missed opportunities. “For example, when you’re done preparing teeth, you can’t say, ‘Oh, I need a pre-op impression or a pre-op photograph.’ If you haven’t done those things in the right order, it may be too late. There’s so much data you need to record on the preparation visit day, that when you’re actually shaping the teeth and doing all the steps, it’s easy to miss something, only to realize after the patient is sent home.”
Executing the Plan
On “Prep Day” Weston follows a clearly delineated checklist while executing the various aspects of the accepted treatment plan. It includes Pre-Op Information, Mockup and Smile Design, Preparations—including tissue contouring, and Provisionals. Weston considers his didactical list to be like an airline pilot’s checklist in the cockpit to make sure everything is done before takeoff. “While I’m in the moment treating this patient, the checklist allows me to focus on the task at hand at that moment and not have to keep an entire list of things and steps in my mind. We have fine-tuned the list so that over the years, we have continued to update as technology changes, etc. The checklist just helps us to get everything we need in the order we need it.”
Weston compares the execution of “prep day” to be like a dance. “It’s important to me to be organized, efficient, accurate, and productive to satisfy my patients.” This approach, he says, helps him bring things together in a timely matter. “I want to make sure this makes sense for me and my patients. I would encourage every dentist to think about the steps they need to be successful and make their own list and not be afraid to have it in the room on prep day so everyone is focused and on the same page.”
The Digital Future
What future checklists may contain in these changing times is anyone’s guess. But one thing seems certain—as the profession becomes increasingly digitized, more dentists will be relying on technology to do more of the work.
“Digital information has made our lives more efficient, accurate, and predictable,” says Brian Schroder, DDS, of San Antonio, Texas. Right now, the aspect of digital technology that has become indispensable to him is digital impressioning, which, he believes, creates a more consistent, predictably accurate result than conventional impression materials.
“Now we can make restorations based on a more accurate replication of what exists in the oral cavity,” he explains. Consequently, the restorations fabricated consistently fit better, mainly because there are fewer errors. “I have encountered few errors other than when human beings enter into the system,” he says. “Computers do exactly the same thing each and every time that you use them. The same cannot be said for people!”
Schroder also uses CBCT for implant planning, another area, he says, where computers have revolutionized the predictability of outcome. “The avoidance of surprises at the surgical event has been dramatically reduced using CBCT,” he says, recalling the early days of implant dentistry. “It was a surgically driven discipline, which resulted in implants being placed exactly where the bone was, but the bone wasn’t always where the bridge, crown, or denture needed to be.” Now using CBCT for implant diagnosis is a whole new world. “Using scanning appliances and surgical guides helps the surgeon accurately place the implant where the restorative dentist wants it.”
Believing that the future of dentistry is in all things digital, Schroder suggests his colleagues get onboard. “People can enter the digital workflow at many different points in the process. Some are involved in the laboratory component, some are involved in scanning and designing and seating restorations, and some, like me, scan restorations and fabricate provisionals conventionally, send those models to a lab, and have restorations fabricated on the models.”
While Schroder doesn’t yet fabricate his own restorations, he expects to in the future. “What is happening in digital restoration fabrication is no different than what’s happening in other parts of life. Computers are revolutionizing our world and they are a welcome addition to restorative dentistry,” he concludes.
1. Greenberg JR, Bogert MC. A dental esthetic checklist for treatment planning in esthetic dentistry. Compend Contin Educ Dent. 2010 Oct;31(8):630-4, 636, 638.
2. Chu SJ. A biometric approach to predictable treatment of clinical crown discrepancies. Pract Proced Aesthet Dent. 2007;19(7):401-409; quiz. 410.
A Leg Up from the Lab
The perspective and experience of Chris Brown and Patrick Bever are as digital as it gets in the laboratory world. They see what is possible with specific and complex cases, and can often put it together for those who can’t make the same connections. CAD technology enables them to create more reliable, esthetic, longer lasting restorations. “We can make those home run restorations doing it right the first time, every time,” says Brown, explaining that CAD provides information like never before. It enables them to see material thicknesses, with warnings about thin spots that could compromise the restoration or to enforce minimum cross-sectional areas on bridge frameworks with custom-contoured connectors.
One advantage is being able to convey this information quickly and conveniently to the dental team. “One of the greatest benefits of working digitally is the ability to communicate much faster, much more directly, and more specifically about certain cases and case requirements,” says Bever. “When we have a design on a computer screen and there’s a question, issue, or concern—whether it’s the clinic’s concern, the lab’s concern, or our concern—through screen sharing, everyone can be on the phone together while looking at the same screen at the same time in 3D. We can move things around and everyone can review it together comprehensively and conveniently.” This, says Brown, is in sharp contrast to how it used to be. “In the past, the lab would have to take the model to the doctor personally and discuss it when it was convenient for everyone.”
What’s So Great about CAD/CAM?
A huge proponent of digital dentistry, including CAD/CAM and CBCT, as well as digital photography, Rosenblatt takes care to assess the pre-existing condition of the teeth prior to treatment. “If the condition is good, and the morphology/shape looks adequate but there’s just some subgingival or interproximal decay, I will actually utilize the existing shape of the teeth and have my software capture images of the teeth before I cut them down,” he says. However, when issues such as poor anatomy or broken cusps hinder his ability to build on the existing structure, he uses the technology either to design a new structure or uses the software to replicate those existing wear facets to design a restoration that will feel similar, from a comfort standpoint.
Rosenblatt makes every effort to be accommodating, and in some cases can wow his patients with same-day dentistry, thanks to his CAD/CAM equipment. “Being able to treatment plan and treat in the same day and finish it is a big deal for patients,” he says, noting that students home from college and patients who need to quickly replace an anterior tooth are especially appreciative.
He says CAD/CAM excels especially in the creation of temporary restorations. “I don’t do a lot of big cosmetic makeovers, but when I’m sending a large case out to a lab, I love to mill out temps.” The marginal fit, he explains, enables him to create temporaries with the same marginal integrity of the final restoration. “They fit like a glove, so even when removed after 2 weeks or more, they fit so perfectly to margins and against the tissue, it’s a dream to do the final restorations because there’s not much bleeding.”
Prep Day Checklist
• Pre-medication, if prescribed
• Radiographs – if not done already
• Digital photos—including American Academy of Cosmetic Dentistry’s recommended 12 “before” images, including a shade reference, lips shown in repose and facial views
• Pre-operative impression for the lab—if not already done, maxillary only at this time, due to possible adjustments on opposing
• Bite records—using centric relation and face bow
Digital Smile Design and Mock Up - if not done at an earlier visit
• Measure pre-op incisor length
• Using lab guide or direct mock up, establish incisal edge position 8 and 9
• Place Trial Smile in the mouth based on design
• Contouring and final shaping of remaining teeth to follow smile design
• Digital photos of mock up—1:2 smile, retracted and facial views
• Patient approval compared to original—note in chart
• Local anesthesia administration
• Fabricate preparation guides—lingual and facial if not using lab guides
• Impression for provisional – if not using lab guide
• Laser tissue contouring
• Prepare upper anterior 6 teeth (lower anterior 6 also for full mouth rehab [FMR])
• Anterior bite jig (new vertical if planned for FMR)
• Prepare remaining upper premolars (lower posterior premolars if needed)
• Posterior bite record with anterior jig in place to complete the record
• Standing stick bite placed on lower anterior
• Digital photo 1:2 retracted of wet dentin with shade reference
• Digital final impressions upper and lower with digital bite record
• Lubricate teeth if indirect technique
• Clean and disinfect teeth and spot etch for direct
• Fabricate provisionals using lab guide or impression
• Seat upper provisional if indirect technique
• Bite record to lower preparations or natural teeth
• Seat lower provisional (FMR)
• Adjust occlusion
• Check all excursions
• Bite records provisional to provisional (FMR)
• Digital photos of provisionals: 1:2 smile; 1:2 retracted; and full-face smile
• Digital impression—maxillary provisionals
• Impression—opposing arch after occlusion finalized