Case courtesy of Frank J Tuminelli DMD FACP, Jay Neugarten DDS MD, Ralph Epstein DDS, Ben Brovnick CDT MDT, Steve Pigliacelli CDT MDT

The ability to help the edentulous patient is paramount. Our team strives to help as many patients as possible with expedited predictable treatment protocols. Both the Trefoil™ system and zygomatic implant treatment options lend themselves to this. We are able to provide fixed solutions immediately and not have patients limited by removable prostheses.

In the following case study, the patient desired fixed restorations and all options were explored. The patient desired an immediate fixed restoration, so the Trefoil™ system was chosen in the mandible for providing a fixed, definitive, full arch prosthesis on the day of surgery*. Trefoil™ system is placed using precise surgical guides and consists of 3 implants, which is sufficient for ideal support. In the maxilla, the hybrid All-on-4® treatment concept with posterior zygomatic and anterior NobelActive® implants was selected.

Treatment overview

Clinical situation and treatment planning

A fully edentulous 57-year-old male patient presented at my clinic in August 2017. He had a conventional removable denture in the maxilla, and no mandibular prosthesis while waiting for stage 2 surgery on a previously placed unknown implant system. These mini-implants could not be loaded with a full-arch prosthesis. The patient presented with adequate bone for placement of NobelActive implants in the anterior region in conjunction with zygomatic implants. This enabled the fabrication of a fixed provisional at the time of surgery and a stable occlusal scheme to build the mandibular prosthesis too.

OPG of edentulous patient

Fig 1 Orthopantomogram (OPG) before treatment shows moderate-to-severe ridge resorption in both jaws. Note the implants and healing abutments in the mandible.

Trefoil™ system in the mandible

The Trefoil™ system consists of 3 implants and a pre-manufactured bar which enables passive fit1. Trefoil™ is universally applicable for most mandibles2. A presurgical evaluation of residual bone height and morphology is done. Once this is accomplished, try-in of teeth and jaw records are completed.  The surgery is scheduled and the Trefoil™ acrylic restoration on the Trefoil™ Bar can be inserted on the same day* or within 24-48 hours3. With good patient hygiene, good soft and hard tissue response can be expected.

Fig. 2:  Cross-sectional CBCT of the mandible shows that the patient is highly suitable for Trefoil™ implant placement
Figs 3 and 4: Following removal of the patient’s prior mandibular implants, the three Trefoil™ Implants were placed in a predetermined position (between the mental foramina) with the aid of different standardized guides and templates

Fig. 5: The Trefoil™ Bar after adjustment of the fixation mechanism and applying opaquer and fixation material to the fixation mechanism components, Fig. 6 OPG of Trefoil™ acrylic prosthesis 3 months after surgery, Fig.7 Trefoil™ acrylic prosthesis in the mandible and conventional removable denture in the maxilla. Note the healthy soft tissue at 6-month follow-up.

All-on-4® treatment concept in the maxilla

The patient had been functioning with a complete maxillary denture but did not like the limitations of a removable prosthesis. The option of the All-on-4® treatment concept for the patient was presented, and he chose this option due to the ability to place without any grafting, an immediately loaded provisional, and the reduced treatment time.**

NobelZygoma™ implants in the posterior were inserted as part of a Zygoma training course that I host at my clinic.

Once the final prosthesis selection was made to zirconia for the maxilla due to its excellent function and esthetics, coupled with excellent tissue response, the decision to fabricate the mandibular prosthesis with the same material was also made. Consequently, the Trefoil™ acrylic prosthesis was replaced with a zirconia restoration. In the standard protocols, the acrylic restoration can also be the final prosthesis with Trefoil™ system.

Fig. 8: Healthy soft tissue around NobelZygoma implants in the posterior and NobelActive implants in the anterior Fig. 9: OPG showing maxillary arch with immediately loaded NobelZygoma implants in the posterior, NobelActive implants in the anterior and the Trefoil™ system in the mandible.

Transforming a life

The photos demonstrate the excellent healing in the mandible following the placement and wearing of the acrylic prosthesis, which is conventional for Trefoil™ system. Once we entered the final phase of treatment, the decision to use the most esthetic material for the maxilla and mandible was made. Using zirconia for maxilla prosthesis with the All-on-4® treatment concept is well documented and straightforward. However, the application of zirconia to the Trefoil™ Bar is a new approach.** Thus, the Trefoil™ Bar was scanned and then the prosthesis milled to fit over it. The intaglio was restored with gingival shade composite. The result for both arches is highly esthetic, durable, functional and biocompatible restorations.

Fig.10: Soft tissue health in the mandible 6 months post-surgery Fig. 11: Full-contour zirconia prostheses in place.

Edentulism treatment outcome with All-on-4® treatment concept and Trefoil

Fig 12  The patient’s final smile

Final remarks

The goals of prosthodontic rehabilitation are first to improve the oral quality of life, which then has a direct correlation to the improvement in systemic health. The ability to give the patient fixed restorations in one day begins the process of oral and emotional healing. The incorporation of Trefoil™ into private practice reduces the time factors inherent in care.3 It reduces chair time and with prefabricated components there is reduction in fees while maintaining the high quality of care we must provide for our patients. The use of zirconia with the Trefoil™ Bar is a first report and opens the spectrum of care for Trefoil™ to additional clinical scenarios.**

*Depending on clinician preference and close cooperation with the laboratory.
** The views, clinical opinions and scientific interpretations expressed in this article are the author’s own and do not necessarily represent the ones of Nobel Biocare.

About the authors

Dr Frank J Tuminelli

Dr. Frank J Tuminelli received his Dental Degree and specialty training in Prosthodontics from Fairleigh Dickenson University School of Dental Medicine. Dr. Tuminelli is a Diplomate of the American Board of Prosthodontics. He is currently the Program Director of Advanced Prosthodontics at the Manhattan Veterans Administration, New York campus, and was the Program Director for Graduate Prosthodontics for the New York Presbyterian Hospital at Queens (member of the Presbyterian Health System) from 2010 – 2016. He served as the Program Director of Advanced Prosthodontics and Implantology, for the NSHLIJ Health System. He is a past President of the American College of Prosthodontists, and past president of The Greater New York Academy of Prosthodontics. Dr Tuminelli is a clinical assistant professor in the Department of Dental Medicine at the Hofstra Northwell School of Medicine. He served as the Team Dentist for the New York Islanders for ten years. He lectures locally and nationally and has authored / coauthored multiple scientific papers. Dr Tuminelli is the recipient of the 2017 Educator of the year award from the American College of Prosthodontists. He maintains a private practice limited to Prosthodontics on Long Island and New York City.

Dr Jay Neugarten

Dr. Jay Neugarten is a graduate of the Columbia University School of Dental and Oral Surgery, where he was named class valedictorian. He completed his residency in Oral and Maxillofacial Surgery at North Shore University-Long Island Jewish Medical Center and earned a medical degree from the Stony Brook School of Medicine. He is a diplomate of the American Board of Oral and Maxillofacial Surgeons. Dr. Neugarten is a Diplomate of the American Board of Oral and Maxillofacial surgeons and a fellow of the American College of Surgeons. He also has lectured both nationally and internationally on a variety of implant-related topics ranging from the single tooth implant to zygoma therapy, the Trefoil™ system as well complex grafting and implant reconstruction of the jaws. He is an associate clinical professor at both New York Hospital Cornell-Weill Medical Center and North Shore University-Long Island Jewish Medical Center, where he is an acEve educator of oral and maxillofacial residents.


  1. Karl M, Carretta R, Higuchi KW. Passivity of Fit of a Novel Prefabricated Implant-Supported Mandibular Full-Arch Reconstruction: A Comparative In Vitro Study. Int J Prosthodont 2018;31(5):440-42.
  2. Aouini W, Lambert F, Vrielinck L, Vandenberghe B. Patient Eligibility for Standardized Treatment of the Edentulous Mandible: A Retrospective CBCT-Based Assessment of Mandibular Morphology. J Clin Med 2019;8(5).
  3. Higuchi K, Liddelow G. An Innovative Implant-Supported Treatment for the Edentulous Mandible: Case Report. Int J Oral Maxillofac Implants 2019;34(2):e13-e16.

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