The Medit i700 scanner, Medit Link software, exocad, and Roland DWX-52DCi 5-axis mill make a completely digital workflow possible.
A 64-year-old female patient presented to the practice with the chief complaint of needing a new denture in the shortest time possible. Due to being a caregiver to her older mother, she couldn’t spend too much time away.
Medit i700 Intraoral Scanner
i700 Intraoral Scanner
Featuring a remote-control button, this scanner makes accessibility and efficiency easy for clinicians, and a smart stitching feature can offer a full view of the arch. It is lightweight while still containing the full technological array of features.
The patient was happy with the esthetics of the old denture, and her main concern was the wear of teeth and loss of retention. The clinical objective was to provide the patient with a new maxillary prosthesis that will reestablish the vertical dimension of occlusion and preserve the esthetics with the minimum number of appointments required for delivery.
The Medit i700 intraoral scanner was used in conjunction with Medit Link software, exocad, and a Roland milling machine for a workflow able to provide the patient with a new denture in just 2 visits.
Initial Examination
The extraoral examination showed a collapse vertical dimension of occlusion. The intraoral examination showed that the patient was fully edentulous on the upper arch, with flabby tissue in the premaxilla area (Figure 1). The patient was missing third and second molars on the lower arch, but the remaining teeth were in good condition, with no caries noticed and no periodontal concerns (Figure 2). The current denture was 15 years old and had signs of wear, including a perforated acrylic area (Figure 3). The patient was not happy with the retention or stability of the upper denture.
Figure 1.
The fully edentulous maxillary arch.
Figure 2.
The mandibular arch.
Figure 3.
The patient’s 15-year-old denture.
Figure 4.
The patient’s old denture is relined and used to make a final impression.
Figure 5.
A digital scan of the patient’s old denture.
Figure 6.
A scan of the old denture and the mandibular arch.
Figure 7.
The brush tool Is utilized to “remove” the outside of the denture.
Figure 8.
The brush tool Is utilized to “remove” the outside of the denture.
Figure 9.
The outside of the denture Is deleted for an edentulous digital model.
Figure 10.
The denture image file Is imported into exocad Virtual Articulator to evaluate excursive movements.
Figure 11.
The denture image file Is imported into exocad Virtual Articulator to evaluate excursive movements.
Figure 12.
The digital model of the final denture Is ready to be milled.
Figure 13.
The final denture is milled as a monoblock and stained to match the patient’s natural teeth and tissue.
Figure 14.
The final denture is milled as a monoblock and stained to match the patient’s natural teeth and tissue.
Traditional analog denture workflows require typically 5 appointments: preliminary impression, final impression, jaw relation records, esthetic try-in, and final delivery. The technique utilized for this case demonstrates an efficient and predictable way of making a complete denture using digital technologies.
In this case, the patient’s current denture was used as a custom tray and relined with Coe-Comfort (GC Fuji) to make a final impression using a modified selective-pressure technique, in which the patient creates functional tissue pressure when occluding on the denture (Figure 4). Once a final impression is created, all excess material is removed. The following steps detail the technique using the Medit i700 scanner after the final impression is taken:
Set up a new case in Medit Link and choose the maxillary arch and denture replica functions.
Open Medit Scan for Clinics and begin scanning the denture in 360 degrees while following the recommended scan pattern suggested by Medit. The Medit Scan for Clinics software generates a digital scan that is a clone of the denture (Figure 5).
Proceed to scan the lower arch and the bite registration. The clinician should end up with a clone of the maxillary denture, a regular scan of the mandibular arch (opposing arch), and a bite record (Figure 6).
After the denture is scanned, select the TrimmingTool in the Medit Scan for Clinics software. Then use the Select Teeth tool in combination with the Brush Tool to select the outside of the denture (Figures 7 and 8).
The outside of the denture is then deleted, resulting in an edentulous model that will be used for the fabrication of the new denture (Figure 9). Note that once the clinician deletes the outside of the denture, the files are still in their original position and their relationship in space is preserved even in other CAD software.
Export the files to be used in combination with the CAD software for the design of the new denture.
The exported files can be imported into virtually any CAD software. In this case, the single denture was designed in exocad using the denture clone duplicate and the bite record scan as a “bite rim” for reference of the position of the new teeth for esthetic purposes. A similar shape of teeth can be selected, and the virtual articular can be used to open the vertical dimension and to evaluate excursive movements (Figures 10 and 11).
The denture was designed (Figure 12) as a monoblock and milled in polymethyl methacrylate (Harvest Dental) using the Roland DWX-52DCi 5-axis milling machine (Roland DGA Corporation). The facial was stained with GC Pink Composite and Kulzer red composite stains. The patient then returned to the office for the final delivery of her new denture (Figures 13 and 14). Upon delivery, the esthetics were evaluated, and the occlusion was checked. The patient was very happy with the fit, function, and esthetics of her new denture.
Conclusion
This case represents a 2-visit delivery of a complete denture using a cloning technique that allows clinicians and laboratory technicians to be more efficient by reducing the number of appointments and clinical time required to deliver a prosthesis. Clinicians can use a Medit i700 intraoral scanner as a reliable tool to scan not only teeth, but also soft tissues and a variety of dental materials including dental prostheses. Furthermore, the Medit Scan for Clinics algorithm has been optimized to allow clinicians to create reliable data, allowing for an exact copy denture replica in 360 degrees, which is still not possible with many other scanners on the market. Furthermore, the benefit for the clinical practice of achieving predictable results in less clinical time can only be achieved with current digital technologies. In this case, the patient benefited from having a denture that satisfied the esthetics and function and achieved her goal of being manufactured in a very short amount of time