Digital Planning for a Maxillary All-on-X Surgery: Considerations for a High Smile Line

CASE REPORT A 68-year-old female presented upon referral from her physician to evaluate her dentition as a potential contributing factor to her elevated white blood cell counts. Her medical history included controlled Type II diabetes and thyroid removal following cancer. After many years since her last dental visit, she presented for a dental evaluation. The oral examination noted numerous abscesses, failing restorations, and missing teeth. The following treatment options were discussed for her maxillary arch: (1) endodontic treatment on multiple teeth, restoring caries, and replacing the missing teeth with long-span bridgework; (2) a full-arch extraction, followed by a locator implant overdenture; or (3) a full-arch, implant-supported, fixed option using a teeth-in-a-day protocol. Upon discussion of the risks and benefits of the 3 treatment options, the patient and her husband elected for the teeth-in-a-day approach for her maxillary arch. The patient’s mandibular teeth would be restored with fillings and crowns. Surgical Planning Upon acceptance of the treatment plan, a full diagnostic workup was completed. This included a full photographic series (Nikon [PhotoMed]), an intraoral scan for study models (CEREC [Dentsply Sirona]), and a CBCT scan (RayScan [Genicore]). Those records were imported into surgical planning software (Blue Sky Plan [Blue Sky Bio]) and were sent to the dental laboratory team for denture fabrication (Artifex Lab, Alexandria, Va). The patient’s upper lip was extremely mobile, ranging from no tooth display at rest to showing several millimeters of gingiva on full smile. This presented a serious challenge for our surgical planning because we needed to predictably plan the correct amount of bone reduction on the day of surgery, but we did not have a method to measure the height that her lip reached. This measurement needs to be extremely accurate because the height of the lip-line determines a significant portion of the prosthetic and surgical planning. The lip-line determines the final height of the patient’s gingiva, which determines the amount of bone reduction needed, which, in turn, impacts the final implant positions. Too little bone reduction would cause a visible transition between the patient’s gingiva and the prosthetic gingiva, but too much bone reduction would compromise the height of bone available to engage our implants; therefore, a more accurate measurement was needed of the patient’s lip-line. Following the recommendations of Dr. Elias Rivera (University of Maryland Prosthodontics) and Dr. Paul Bylis (Innovative Dental Design, Glen Burnie, Md), the patient was brought back to take one additional record. This new record would objectively determine her lip-line when she displayed the fullest smile. This would form an accurate and repeatable landmark of where the lip extends on full smile rather than have our full surgical plan relying on an estimate from a photo. The premise of this record was the following: create a putty matrix in the patient’s mouth that represents the exact level of her lip on full smile, and then transfer that lip-line record into the digital planning software. To accomplish this, we created a putty matrix (Panasil Putty Soft [Kettenbach LP]) on her study model in preparation for the appointment. At the appointment, we seated the matrix in her mouth, had her make her “biggest smile ever,” and then used a pen to mark her lip-line on the putty. The stent was cut along that line and placed back into her mouth, and then small modifications were made to the stent based on observing her talk and smile. Photos of the patient wearing this stent were then taken. After this appointment, the matrix was placed onto her study model, and a No. 8 round bur (Brasseler USA) was utilized to indent the flange of the matrix (representing the patient’s lip-line) onto her cast. This cast was digitally scanned, imported into the implant planning software, and then aligned with her other models/CT scans (Figure 3b). The digital plan now had a defined plane of the patient’s exact lip-line, aligned with her CT scans/other models, which represents the maximum height that her lip extends and, therefore, the coronal-most position of the gingiva. This was a critical piece of information, which allowed for the virtual design and planning of the other aspects of the case. The bone level was digitally cut to 3.0 mm apical to the height of the gingiva. Then the implants were placed to the height of the bone, and the prosthetic clearance was made to be 15.0 mm from the platform of the implants to the occlusal surface of the prosthetic. All implants and surgical guide stabilization pins were digitally placed based on the prosthetic plan and anatomical boundaries. The surgical plan called for the fabrication of 3 guides: a pin guide, a bone reduction guide, and an implant guide. All 3 guides’ placements were triangulated based on 3 stabilization pinholes. This is unlike a typical single-tooth implant, which uses a tooth-borne guide and seats on the adjacent teeth for orientation. The first guide is the pin guide, which is used to determine the 3 pinholes. The purpose of these pinholes is to orient the subsequent 2 guides, which are fixated and stabilized by 3 pins. For this case, the pin guide was made to be placed following extraction of the teeth and to be seated over the patient’s edentulated arch. Since there was not an actual model of how the patient’s bone would present after the teeth were extracted, a model was generated by modifying the segmented maxillary model to virtually extract the teeth (Meshmixer [Autodesk]). Next, this edentulous bone model was imported into the planning software, and a vacuum-formed guide was fabricated with 3 pinholes. Surgically, the pin guide is placed following the extractions, the 3 holes are drilled, and then the guide is set aside. The next guide is the bone reduction guide: a thin guide in which the coronal portion represents the new level of the bone; all bone coronal to the bone guide should be reduced to that level. The final guide is the implant guide, which also engages the 3 pinholes and was used with our fully guided implant kit (TAG Dental [Genicore]) to predictably place all 8 planned implants. All 3 guides were 3-D printed (Digi3DWorks) in preparation for the day of surgery. Surgery Day On the day of surgery, local anesthetic was administered, and a full-thickness mucoperiosteal flap was laid. Then the patient was atraumatically and fully edentulated on the maxillary arch, and all infected tissue was curetted until solid bone was reached. Due to the large amount of bone reduction required for this procedure, a large flap had to be laid to allow the guides to seat apically enough. Following edentulation, the pin guide was seated on the bone, and the 3 pinholes were created. Next, the bone reduction guide was placed, engaging the 3 pin holes and showing exactly how much bone needed to be reduced . A large bone-cutting bur (Global Dental Products) was used with copious irrigation to reduce the bone to the level of the bone reduction guide . The bone reduction guide was then removed, and the implant guide was placed, engaging the same 3 pinholes. Implants (TAG Dental implants [Genicore]) were placed using fully guided protocols, bone (MinerOss [BioHorizons]) and MIS Implants Technologies’ collagen membranes (Genicore) were placed, the flap was approximated using simple interrupted sutures, and a final CBCT scan was taken to confirm the placement of the implants. Upon confirmation of successful implant placement, multi-unit abutments and cylinders (TAG Dental products [Genicore]) were placed on the implants, the maxillary denture was seated over the cylinders and was picked up with acrylic (Lang Dental), the prosthetic was adjusted/polished, and the palate of the denture was removed. The finalized temporary was inserted, engaging 7 of the 8 implants, and occlusion was checked. The eighth implant was not engaged due to insufficient insertion torque and, instead, was buried with a bone healing cap. The screw access holes were sealed with light-body putty (Kettenbach LP). Photos at the one-day follow-up revealed that the patient was healing well.

Oral Medicine and Radiology Prosthodontics

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Block Bone Grafting – Full Arch Restoration

All types of bone grafting procedures from using guided bone regenerative techniques to block bone grafting (Chin or mandible) are carried out at the practice. When using these techniques the patient is usually sedated for a more comfortable procedure. Sinus grafting is also carried out where there is limited bone volume in the posterior maxilla to place implants. The augmentation can be done using either autogenous bone graft or using a substitute usually a xenograft material (Bio-Oss). Case Overview This patient was referred for implant therapy as she has completely failed upper dentition. The implants were placed 15 years earlier but were affected by peri-implantitis. The full mouth clearance and implant removal were followed by block bone grafting in the upper incisor region prior to any implant therapy. Sinus grafting is also carried out where there is limited bone volume in the posterior maxilla….. After maturation of the graft 6 implants were placed and restored with 12 unit fixed screw-retained bridgework. The final picture was taken after 4 years in function. Procedure STAGE 1 The upper arch is unrestorable with failed bridgework and dental implants. STAGE 2 After full clearance & bone augmentation, computer guided surgical guides were used for optimal positioning of the dental implants. STAGE 3 The upper jaw shows 6 dental implants placed & restored with 12 tooth bridge & lower left molars replaced with 2 dental implants. STAGE 4 The final smile shows the beautiful porcelain fixed bridge with an extremely happy patient. This picture was taken in 2006. Clinical Prognosis The long term prognosis is dependant on both the planning, execution and maintenance of the bridgework and dental implants. The planning stage was carried over a number of visits including CT scans and nothing was rushed. The actual treatment time was just over 9 months and the final bridge was fitted in 2006. This bridge has given over 11 years (as of 2018) of service with no complications with any of the implants. The patient is reviewed twice yearly for a complete dental examination and dental hygiene. The patient is extremely happy with the outcome as we are also .

Aesthetic Dentistry Implants + 3 more

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Dental implant bridge supported by four or more implants

For many patients missing all their teeth can have a devastating impact on quality of life. For replacement of all teeth, we have 2 main options: A removable prosthetic denture secured on two or more implants using mechanical anchors or a bar. A fixed prosthesis consists of a dental implant bridge supported by four or more implants. Implant retained bridgework allow patients to function normally without restrictions, these are easily maintained by good home care. Case Overview This pleasant gentleman was referred in 2007 for the possibility of implant therapy as he did not wish to have a removable denture in the lower jaw. as he had suffered from severe gum disease, this is a high-risk factor for future implant complications…… A diagnosis of severe chronic periodontitis was made along with cosmetic concerns. Unfortunately, due to the severe bone loss present, the natural teeth could not be saved. The decision was made in conjunction with the patient to make a new complete upper removable denture and a fixed implant bridgework in the lower. Procedure STAGE 1 The radiograph shows extreme bone loss around all the remaining natural teeth. Unfortunately, none of these teeth had a good long-term prognosis. STAGE 2 The natural teeth were extracted and 6 dental implants were placed at the same time. The final fixed bridge was made from acrylic wrapped onto a cad/cam titanium frame. The upper jaw was restored with a removable complete denture. Clinical Prognosis Prior to starting the treatment, the patient was made well aware of his role during and post-treatment. As he had suffered from severe gum disease, this is a high-risk factor for future implant complications. He has been attending regular hygiene appointments on a twice-yearly basis and an annual review with the dentist. After 9 years in function there have been no complications and with his excellent home maintenance, we hope to get several more years without any issues. “The result has been I now have a full set of implanted teeth, which has helped me return to a normal life, I can eat, speak and drink normally.

Aesthetic Dentistry Dental Materials + 3 more

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Anterior Aesthetics Through Composite Artistry

CASE REPORT Diagnosis and Treatment Planning A patient presented to our office for a consult regarding treatment options to correct the shapes and positions of his front teeth. He was concerned with cost and worried about “grinding down” his teeth if he were to choose porcelain veneers. His previous dentist proposed Invisalign clear aligners (Align Technology), followed by a reshaping of his central incisors (teeth Nos. 8 and 9). My standard protocol for treatment planning a case following full diagnostic workup (radiographs, full periodontal charting, etc) is to take a full series of photographs and diagnostic models. A PowerPoint digital slide series is then created. Borrowing from Dr. Frank Spear, repose photos are used to assess the proper amount of display for the central incisors. Smile photos help to create a smile that is in harmony with the patient’s lower lip. In this case, based upon the information gathered, it was clear that reshaping the central incisors would make for an unattractive smile, as tooth position at rest would not offer age-appropriate display. Reshaping would also bring the incisal edges of the centrals even with the laterals, causing the corridors to display a longer incisal length than the anterior segment; this would create a reverse smile line. The treatment plan proposed was to use Invisalign clear aligners to treat the crowding of the anterior segment. In this way, a healthier occlusal scheme would be achieved, and then a mockup of the case would be done. The patient would then decide if he wanted to proceed with our recommendations for direct composite additions to add incisal length to teeth Nos. 7 to 10 or simply have teeth Nos. 8 and 9 reshaped. Post Invisalign Workup Once the anterior teeth were aligned, new photos and models were taken. The patient was planning to attend a reunion and wanted the front teeth treated prior to Invisalign refinement, which would gain some arch width in the maxillary corridors. It was decided that we could proceed with final anterior aesthetics and then create new records for Invisalign to complete the final expansion of the maxillary bicuspids. I waxed up the anterior teeth and transferred it using a lab putty matrix (Panasil [Kettenbach LP]) and a bis-acryl provisional material (Integrity [Dentsply Sirona]). The patient was thrilled with the look and decided to proceed with treatment. Preparations To prepare a putty matrix, a Bard-Parker 20 blade was used to remove the facial and buccal portions of the matrix, preserving the incisal edges. This establishes the incisal “footprint” of the teeth being treated, allowing the clinician to form an incisal halo, or “French tip,” on the restoration. The basic principles to creating an invisible restoration were taught to me by Dr. Buddy Mopper. They are as follows: (1) you need to create a long, infinite bevel ; (2) opacity must be controlled; (3) a microfill should be applied as the final surface material; (4) the microfill should end on etched, unprepped enamel; and (5) use discs, not rubber points, to finish margins and flat surfaces. The preparations involved form an “infinite bevel,” heavier at the incisal and feathering toward the middle third. Addition of Composite The technique I have developed involves 3 shades: White Opaque (WO) (Esthet•X HD [Dentsply Sirona]), White Enamel (WE) (Esthet• X-HD), and a corresponding body shade (Renamel Microfill [Cosmedent]). To begin, with the guide in place, WO is placed in the putty guide and contoured to form a “frame” of the shape along with the most labial position of the incisal edge. This addition blocks out shadowing from the back of the mouth and creates a halo effect. The next composite addition is to use shade WE, placed within the WO frame. The WE composite allows for light refraction through the incisal third, thus creating a very natural appearance. Care must be taken to not add material facial to the WO composite placement. This addition should be striated in a vertical fashion using the clinician’s preferred instrument. A white opaquer (Creative Color [Cosmedent]) can be conservatively placed with a composite brush (Cosmedent) . This step mimics the dentin-enamel junction and forms minor milky white craze lines. The final addition of composite is done using the body shade. For this step, Renamel Microfill is used. This is an inherently weaker composite due to its low filler content and .04-µm particle size. It should never be placed in a load-bearing situation. It is best used as a thin, final layer, because it has unparalleled polishability and color stability. This layer is added in a generous amount at the incisal portion of the restoration. This is done using a wetting agent (DeTak [TAUB Products]) that helps break down surface tension of the material before it is manipulated toward the cervical region. These steps are repeated to the distal and mesial areas being restored. Finishing First, turn off the water! The composite finishing steps should be done dry, because (in my experience) dry polishing, in combination with good lighting, will produce much better results. First, a composite finishing bur (ET6 [Brasseler USA]) with a light touch is used to refine any areas that were not sculpted ideally during the addition phase and to remove any excess composite at the CEJ. Make sure to remove any scratches or other imperfections in the resin. These areas can clearly be seen because any scars or voids will fill with composite dust. Your assistant should blow air onto the surface to allow for visualization of these dust-filled sites. Next, use discs, such as FlexiDisc (Cosmedent), to continue polishing the restorations (Figure 7a). Begin with the coarse grit disc and then progress through the entire series to superfine. Using polishing discs in a dry setting with good lighting allows the clinician to perfect the proximal line angles. One will see light refract back from the middle third of the tooth. This recipe permits the operator to maintain the flat surfaces of incisors in 3 planes while achieving a mirror-like enamel finish. Adding Developmental Anatomy and Final Polishing I have developed an easy way to cultivate realistic surface topography on a composite restoration. It involves using a polishing point, such as Super Fine CeraMiste points (Shofu Dental). (CeraMiste points were originally developed to polish porcelain.) While I prefer an electric handpiece, either an electric or an air-driven handpiece can be used. When using an electric handpiece, run it at a slow speed between approximately 18,000 and 20,000 rpm. Using no water, decide where to place the anatomy. This can be done using a pencil to outline the sites. Now, using a vertical sweeping motion, use the pointed third of the point to develop a depression in the surface of the resin. Once this is established, begin to lay the belly of the CeraMiste point into the depression, with the pointed end toward the cervical and the wide end at the incisal. Using the same vertical sweeping motion from cervical to incisal, with good lighting and no water (dry), the clinician can create lifelike surface texture. Repeat this sequence to create the appearance of 3 distinct lobes. Lastly, with a light vertical stroke, sweep the surface between the 2 developmental recesses to create perfect surface texture. Once this is done, the final step is to place a composite polishing paste, such as Enamelize (Cosmedent), on a mini felt pad (FlexiBuff [Cosmedent]) and, using a light touch at a slow speed (4,000 rpm electric) and working dry, buff the restorations and watch the artwork pop! Occlusion My occlusal schemes are based on the teachings of Dr. Ross Nash. He is an invaluable teacher/mentor for any astute clinician who may be looking for straightforward approaches to full-mouth rehabilitation. Anterior guidance should allow for the coupling of teeth Nos. 8 and 9 against teeth Nos. 24 and 25. An excursive right and left movement should gain canine rise, while all movements should attempt to clear the laterals of any contact. In this case, tooth No. 6 was not performing this function. As a courtesy to the patient, and to protect the rest of the case from traumatic forces, we performed a complementary augmentation of the incisal edge of tooth No. 6 to create proper guidance.

Aesthetic Dentistry Smile Designing + 4 more

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The Use Of Extreme Magnification In Dentistry

The application of the operating microscope in clinical dentistry can be traced to Apotheker in 1981.9 He converted a medical operating microscope for use in endodontics. Use of the operating microscope has been shown to improve visual acuity, providing increased precision in surgical care as well as in certain other types of treatment. In addition, the operating microscope provides important ergonomic benefits. The clinician sits in a comfortable upright position, relying upon directed patient movements or movements of a mirror to visualize the surgical site. The balanced position of the clinician when using the microscope may help reduce musculoskeletal injuries that are common among members of the dental profession. In addition to the ergonomic benefits, dentists using the operating microscope have discovered that the video camera attached to the microscope can be useful by providing both patients and the auxiliary staff with the ability to observe treatment in real time. The microscope, like intraoral cameras, allows for co-observation. In addition, this feature makes it possible for patients to observe treatment. Mehrabian has shown that as much as 55% of the understanding that occurs in verbal communication is through visual cues, and that only 7% of the comprehension in communication comes from the words we use.Stated differently, patients remember more of what they see than what they hear. Clinicians have found that the images from the operating microscope are a benefit in educating patients about their treatment needs. The ability to easily document a procedure using digital microphotography and microvideography with cameras attached to the operating microscope opens up new possibilities for patient education, documentation for professional presentations, and medical/legal documentation. In addition to the ergonomic benefits and documentation provided by the operating microscope, general dentists have found that it allows for significant enhancement in the precision of restorative and prosthodontic care. Martignoni, in his textbook on prosthodontics published in 1990, was among the first to discuss how the microscope might be useful in operative dentistry.26 Since that time, several clinicians have suggested that this device can be used to improve tooth preparation and the final restoration in fixed prosthodontics. RESOLUTION OF THE HUMAN EYE AND MAGNIFICATION IN CLINICAL DENTISTRY Carr37 reported that the human eye, when unaided by magnification, has the ability to resolve or distinguish 2 discrete lines or objects separated by a space of 200 µm (0.2 mm). If the lines are closer together than 0.2 mm, the eye will see them as a single line. Magnification improves the ability of the eye to resolve these objects, and allows the clinician to see greater detail than is possible with the eye alone. For example, 2x magnifiers such as telescopic loupes improve resolution to 100 µm, and 4x loupes improve the resolution of the human eye to 50 µm, or 0.05 mm. Amsted or single-lens loupes are simple clip-on lenses that helped magnify the operating field. These single-lens systems have been replaced by multiple-lens telescopic loupes that are commonly used today. These magnifiers are available in either a flip-up variety or are directly mounted on the lenses of the glasses. Their magnification range is from 2x to 8x. Typically, loupes with magnification greater than 3.5x require some form of illumination from an accessory headlamp for adequate visualization of the operating field. Typically, dentists will initially use loupes with a magnification of 2.5x, and employ them for difficult procedures requiring enhanced vision such as endodontic therapy or veneer cementation. After an initial adjustment period, the dentist will begin to use the loupes for all procedures. In British Columbia the routine use of surgical telescopes by dentists has increased from approximately 20% in 1986 to 75% in 2000.38,39 Dentists may then change to higher-powered loupes used with illumination. Dentists have realized that many details that are potentially important in the provision of care are beyond the resolution of the human eye. Incipient carious lesions, tooth fractures, preparation of crown margins, and crown margin evaluation during insertion are often determined by tactile means. At magnifications above 4x to 6x, visual enhancement provided by the microscope may lessen the reliance on tactile sense. One study has shown that an experienced clinician with a sharp, new explorer can determine marginal gaps in the range of 35 to 50 µm.40 Microscopes, in contrast to telescopic loupes, allow multiple steps of magnification between 2x to 40x. The microscope provides true stereoscopic vision through the binoculars, and the coaxial illumination from halogen, metal halide, or xenon bulbs creates shadow-free lighting. THE ROLE OF THE OPERATING MICROSCOPE IN THE PREPARATION STAGE OF FIXED PROSTHETICS The preparation phase of fixed prosthodontic care is technically demanding. Many factors determine the final design of the preparation, including the required reduction of tooth structure, detection of marginal caries, fractures, furcations, and the need for the margins of the restoration to be placed on solid tooth structure. In addition, the clinician must consider the aesthetic, functional, and biologic principles regarding placement of the margins of the restoration (supragingival, gingival, or subgingival), and the type of margin best suited for the tooth (shoulder, bevel, or chamfer). While the successful provision of inlay, onlay, and crown restorations depends upon a solid understanding of the above, successful treatment is predicated on the ability of the clinician to clearly and distinctly view the operating field . Leiknius and Geissberger have shown that magnification (low-magnification telescopic loupes), when used by dental students, helped reduce errors in preparation design and laboratory processing by half when compared to a control group not using magnification. To read from the source, click on the link below :

Dental Ergonomics Digital Dentistry + 1 more

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