Pterygoid Anchorage of Subperiosteal Implants: An Overview and Case Report

Antoine Diss, Augustin Lerebours, Cyrille Grébonval, Laurine Birault

Full text link: https://pubmed.ncbi.nlm.nih.gov/40458381/

Pterygoid Anchorage of Subperiosteal Implants: An Overview and Case Report

1. Scientific reference

• Study title: Pterygoid Anchorage of Subperiosteal Implants: An Overview and Case Report
• Authors: Antoine Diss, Augustin Lerebours, Cyrille Grébonval, Laurine Birault
• Scientific journal: Cureus
• Publication year: 2025
• DOI: 10.7759/cureus.85175

Source analyzed: scientific article published in Cureus in 2025, available under the Creative Commons Attribution License CC-BY 4.0.

2. Scientific context

Severely resorbed maxillae remain one of the most challenging situations in implant dentistry, particularly when conventional implant placement is limited by insufficient residual bone volume. Advanced maxillary atrophy, classified as Cawood and Howell class V or VI, often requires complex reconstructive procedures when conventional implant-supported rehabilitation is considered.

Modern subperiosteal implants have regained interest through the development of digital workflows, three-dimensional imaging, CAD/CAM design, and additive manufacturing technologies. These innovations allow the fabrication of patient-specific titanium frameworks adapted to complex anatomical conditions.

The present study explores the integration of pterygoid anchorage into digitally designed subperiosteal implants. The authors investigate whether the pterygoid region can provide an additional posterior support zone in severely atrophic maxillae, complementing traditional anchorage areas such as the canine pillars and zygomatic buttresses.

3. Study objective

The primary objective of this report was to assess the clinical feasibility of incorporating pterygoid anchorage into custom-made subperiosteal implants for the rehabilitation of an extremely atrophic maxilla.

The authors aimed to demonstrate whether the pterygoid region could be used as an additional fixation area to enhance implant stability and mechanical support in a complex implant rehabilitation scenario.

4. Methodology

This publication is a technical report combined with a clinical case report.

The article describes the treatment of a 71-year-old fully edentulous female patient presenting with severe maxillary bone atrophy classified as Cawood and Howell class VI. Two patient-specific subperiosteal implants were digitally designed using a workflow based on cone-beam computed tomography (CBCT), digital smile design, and computer-assisted implant modeling.

The implants were manufactured from Ti-6Al-4V ELI grade 23 titanium using Direct Metal Laser Sintering (DMLS) additive manufacturing technology. The design incorporated fixation points in the canine, zygomatic, and pterygoid regions. Additional bicortical pterygoid screws were planned to pass through the pterygomaxillary suture to provide posterior anchorage.

5. Main results

The reported case demonstrated that the integration of pterygoid anchorage into a customized subperiosteal implant design was technically achievable.

Following digital planning, additive manufacturing, and surgical placement, the two implants were stabilized using osteosynthesis screws positioned in multiple anatomical regions. A provisional fixed bridge incorporating a titanium framework and PMMA material was delivered immediately after surgery.

The authors reported satisfactory initial implant stability and positive patient satisfaction following treatment. They also suggested that extending implant support toward the posterior region may contribute to improved mechanical behavior by helping counteract forces associated with anterior cantilever effects in severely resorbed maxillae.

However, the reported findings remain limited to the observations obtained from this single clinical case and do not establish comparative superiority over other treatment options.

6. Clinical analysis

This publication provides an interesting perspective on the evolution of subperiosteal implant therapy in cases of advanced maxillary bone loss. Historically associated with earlier generations of implant design, subperiosteal implants have been reconsidered through modern digital technologies that enable individualized adaptation to patient anatomy.

The potential clinical interest of pterygoid anchorage lies in the possibility of using a posterior anatomical support area that may remain available despite severe alveolar resorption. In the presented case, the authors suggest that posterior extension of the implant framework could increase support and improve resistance to unfavorable biomechanical forces.

From a clinical interpretation standpoint, the study demonstrates feasibility rather than definitive treatment effectiveness. The reported outcome cannot be generalized because it is based on a single patient, without a control group or direct comparison with other approaches such as zygomatic implants or graft-based reconstruction protocols.

The findings should therefore be considered as an exploratory contribution to implant rehabilitation strategies rather than as evidence supporting routine clinical adoption. Further biomechanical investigations and long-term clinical evaluations are required to determine the actual role of pterygoid anchorage in subperiosteal implant therapy.

7. Clinical applications

The approach described in this article is mainly relevant for patients presenting with extreme maxillary atrophy, particularly when conventional implant placement is compromised by insufficient bone availability.

The technique may be considered within complex full-arch implant rehabilitation strategies involving digital planning, CAD/CAM workflows, guided surgical concepts, and additive manufacturing of customized titanium implants.

The reported case also illustrates a possible application in edentulous patients requiring fixed prosthetic rehabilitation without extensive bone augmentation procedures. Nevertheless, the precise indications, patient selection criteria, and long-term predictability of this approach remain to be established through additional clinical evidence.

8. Level of evidence, limitations, and transparency

The study represents a case report with a technical description, corresponding to a limited level of clinical evidence. Such publications are useful for documenting feasibility and introducing innovative approaches but cannot establish treatment superiority or provide definitive clinical recommendations.

The main methodological limitations are related to the single-case design, absence of a control group, lack of comparative evaluation, and absence of long-term outcome data in the information provided.

The authors disclosed professional relationships: Augustin Lerebours reported employment with Biotech Dental, and Cyrille Grébonval reported employment with Glad Medical. The article also states that a patent application was submitted in March 2025. These elements should be considered as part of transparent interpretation of the publication.

9. Key points of the study

• Study type: Technical report and clinical case report
• Level of evidence: Low level of evidence (single clinical case)
• Population: One 71-year-old fully edentulous female patient with severe maxillary atrophy
• Number of implants: Two customized subperiosteal implants
• Follow-up duration: Not specified in the provided information
• Primary outcome evaluated: Clinical feasibility of adding pterygoid anchorage to subperiosteal implant design
• Main finding: Pterygoid anchorage was technically achievable and provided additional posterior fixation in the reported case
• Scientific conclusion: Pterygoid anchorage may represent an additional design option for severely atrophic maxillae treated with customized subperiosteal implants
• Main limitations: Single case, absence of comparative data, lack of long-term validation

10. Scientific impact

This study contributes to the renewed interest in modern subperiosteal implants by illustrating how digital dentistry and additive manufacturing can expand treatment concepts for patients with severe maxillary atrophy.

Its main contribution is the description of pterygoid anchorage as an additional fixation component integrated into a patient-specific subperiosteal implant design. The publication extends previous concepts of anatomical anchorage by combining traditional support areas with posterior fixation through the pterygoid region.

From a scientific perspective, the article represents an early clinical exploration of an emerging technique rather than definitive evidence of clinical superiority. It provides a basis for further investigation into biomechanical behavior, implant design optimization, and long-term clinical outcomes.

Future research should clarify whether this approach offers measurable advantages regarding implant stability, prosthetic performance, complication rates, or patient-centered outcomes compared with existing solutions for severe maxillary atrophy.

11. Editorial conclusion

This study presents an innovative approach to complex implant rehabilitation by combining customized subperiosteal implants with pterygoid anchorage in a severely atrophic maxilla. The reported case demonstrates that this design modification can be technically performed using modern digital workflows and additive manufacturing.

Nevertheless, the available evidence remains preliminary. The findings should be interpreted as a feasibility demonstration rather than definitive proof of clinical effectiveness. Additional clinical studies, biomechanical analyses, and longer follow-up periods are required to determine the long-term relevance of pterygoid anchorage in contemporary implant dentistry.