Implant Hybrid Esthetic Analysis

As with any complex prosthetic restoration, diagnostics are critical to exceeding esthetic and functional expectations. To understand expectations with these implant restorations there must be clinical and technical collaboration that includes diagnostic digital photos. The concepts and principles used in cosmetic dentistry originated in removable prosthetics from J.P. Frush and R.D. Fisher’s literature on esthetics or dentogenics. These prosthetic concepts of anterior tooth position are extremely relevant in the smile design analysis for hybrid implant prosthetics. Communicating with digital photos during the esthetic try-in will help the technologist visualize why and where teeth need to be repositioned according to facial landmarks. The facial, lateral or profile, rest, and smile photos are absolutely necessary to conduct a proper esthetic analysis of of the existing prosthesis and during the treatment of the provisional and definitive.

In this article we will present a small segment of the clinical and technical process that focuses on improving esthetic collaboration between the clinician and technician.

The patient had a maxillary All-on-Four (NobelProcera, Nobel Biocare, www.nobelbiocare.com) implant restoration, with four Bränemark implants (Figure 1). The midline was displaced and needed to be moved to patient’s right (Figure 2 through Figure 4). Note in Figure 4 the line drawn at the palatal midline according to anatomical landmarks median raphe. The smile was analyzed with a transitional prosthesis (Figure 5) then calibrated with the center of nose and ala-to-ala vertical lines determining placement of canines (Figure 6).

The transitional prosthesis was duplicated and used to scan with master fixture level cast for designing milled bar. The bar design was critical to achieving the desired esthetic and functional expectations, since tooth placement should determine bar position. The anterior section of bar was designed to support anterior placement of teeth (Figure 7) with lateral view as shown in Figure 8. Figure 9 shows the lingual view of the bar with beveled anterior abutments and raised posterior screw access channels, which will be adjusted during tooth arrangement. Figure 9 illustrates the space between the bar and the residual ridge. Understanding how to read these digital designs in relation to anatomy and prosthesis is critical to creating a properly designed milled bar. A facial view of digital designed prosthesis is shown in Figure 10, providing an analysis of space between the residual ridge and the bar.

The finished milled bar is shown in Figures 11 and 12 from an occlusal and side view to illustrate the restorative space perspective opposing the mandibular casts. Note a minimum of 12 mm is necessary to design a milled hybrid bar with 15 mm being the ideal. The teeth are now set and arranged on the milled bar with screw access channels reduced as necessary for buccal placement and occlusion (Figures 13 and 14).

Photos of the centric occlusion (Figure 15) and the protrusion (Figure 16) were taken to analyze esthetic anterior tooth placement and functional position. The anteriors seem to be in a good position relative to mandibular teeth and the lip line. An analysis of the lateral view is shown in Figures 17 and 18, depicting the incisal edge position during speaking and smiling. According to the photos, the anterior right and left sides seem to be placed in a good esthetic and functional position. A facial calibration (Figure 19) of the anterior incisal edge tooth position in relation to interpupillary horizontal line shows the patient’s right side is higher than the left. The vertical midline at the center of face determines that the midline needs to be re-positioned to patient’s left. Verifying function position is critical to proper tooth placement as shown with protrusive photo Figure 20. The esthetic try-in was reset according to instructions and analyzed (Figure 21). A palatal analysis is shown for esthetic placement of teeth Nos. 8 and 9 in relation to incisive papillae and palatal midline suture (Figure 22). The definitive implant supported prosthesis was then verified at delivery with palatal midline (Figure 23).

The definitive hybrid implant prosthesis is shown in Figure 24 with proper position of teeth in relation to facial calibration and analysis. The interpupillary line is parallel to the incisal edge smile line; center of face line on nose is at midline of teeth Nos. 8 and 9. The widest part of nose ala to ala measurement is at the long axis of the canines and the canines are rotated with the mesial aspect out facially. The distal aspect of the canines should not be visible and vertical lines are at the long axis point.

Digital photos during treatment of an edentulous patient should be the standard for clinical and technical communication. When the clinician and technician communicate at this level, they are truly collaborating to exceed esthetic and functional expectations. Digital photo analysis should be done at delivery as well to verify esthetic harmony with face and anatomical landmarks.

Robert Kreyer, CDT
Partner
Custom Dental Prosthetics Inc.
Los Gatos, California

William Perry, DDS
Owner
Private Practice
Los Gatos, California