Results:
The patient presented for the surgical phase of treatment, consent forms were reviewed and signed by the patient. Local anesthetic was applied to the maxillary arch using 4% Articaine + 1/200,000 epinephrine. The surgical guide was inserted to verify seating on the arch. A 2 mm wide screw was placed through the surgical guide at sites 5, 8 and 12 to stabilize the guide and prevent motion during osteotomy preparation. (Figure 16) Utilizing Guide Right 3 mm depth stop drills (Figure 15), sites #4, 6, 10 and 13 osteotomies were prepared through the 3 mm guide sleeves in the surgical guide. The implants were placed 4-5 mm below the alveolar crest as was planned to provide adequate room for the Conus abutments. The fixation screws were removed, and the surgical guide was removed intraorally. An incision was made at the center of the ridge and soft tissue flapped to expose the crestal bone with some buccal and palatal ridge exposure. A surgical carbide was then utilized to reduce the crestal bone across the arch to 1mm from the platform of the implants at the four sites. Alveolar crestal reduction was performed after implant placement to prevent loss of stability of the surgical guide. Cover screws were placed and soft tissue reapproximated and fixated with 4 0 nylon sutures in an interrupted pattern. The current maxillary denture was relined with Karlin, Easy Soft Liner to accommodate the reduction in crestal height performed with implant placement. A panoramic radiograph was taken to document implant placement. (Figure 17) The patient was dismissed.
The patient was allowed to heal for 4 months during which periodic post-operative visits were performed. The implants were uncovered, and healing abutments placed. Following a 2-week healing of the soft tissue, the healing abutments were removed intraorally, and impression abutments placed. (Figure 18) A full arch impression was taken with Permadyne (3M, St Paul, MN) heavy & light bodied polyether impression material in a custom tray to start the restorative phase of treatment.
A master cast was poured in ResinRock (Whip Mix, Louisville, KY) with implant analogs and GI-Mask (Coltene/Whaledent, Cuyahoga Falls, OH) to replicate the soft tissue architecture. Inter-fixture spacing was verified with a verification jig fabricated from GC Pattern Resin (GC America, Alsip, IL).  An impression of the mandibular arch was taken with alginate. The master cast was mounted with a Hanau facebow on a modular, semi-adjustable articulator.  A jaw relation record was made with a custom Triad (Dentsply Sirona, York, PA) resin baseplate with a wax rim and Blue-Mousse (Parkell, Brentwood, NY) VPS bite material.  The wax rim was marked to show the desired midline and tooth position, then a protrusive check bite was made to set the occlusal parameters on the articulator. The patient chose shade Vita B1.
A try-in of the full arch with denture teeth (Ivoclar Vivadent, Amherst, NY) to confirm esthetics and function. The teeth were positioned to optimize esthetics and phonetics, but were repositioned, per the patient’s request until a satisfactory result was achieved and patient approval was acknowledged. A buccal matrix was made on the master cast with Express VPS putty (3M) to preserve the tooth position. The dental laboratory fabricated 4 custom Atlantis Conus abutments (Dentsply Sirona) and a cobalt-chrome denture framework/baseplate that incorporated the SynCone caps (Dentsply Sirona) that would retain to the Conus abutments. (Figure 18) The denture teeth were placed on the master cast with the Conus abutments and denture framework present. Utilizing the buccal matrix a new full arch wax try-in was fabricated with a spacer over each Conus abutment.
The patient returned to the office and the Conus abutments were placed intraorally using the insertion guide and verified clinically and radiographically for fit and orientation.  A new jaw relation was made and verified. The wax try-in was inserted intraorally over the Conus abutments to verify fit, occlusion and get patient approval on the esthetics. The wax try-in was returned to the lab for processing.
The maxillary overdenture was processed without the incorporation of the Syncone caps, which would be picked up clinically using Chairside resin (Zest Dental Solutions, Calsbad, CA). The finished maxillary overdenture was returned to the office for insertion.
The finished overdenture was tried in with the Syncone caps seated on the Conus abutments and passive fit was confirmed as well as the occlusion and esthetics. Chairside resin was placed into the sites in the intaglio of the denture where the abutment spaces were present. The overdenture was then seated intraorally, and the patient instructed to occlude. Upon set of the resin the overdenture was removed with the Syncone caps embedded within. Any resin flash was removed around the Syncones and the areas polished. The overdenture was reinserted intraorally and retention was confirmed as well as occlusion. (Figure 19) The patient was appointed for a follow up appointment the following week to check fit and function.