The Peri-Implantitis We Designed In
A Spanish Society of Periodontology (SEPA) expert consensus consolidates surgical and prosthetic design factors — emergence angle, abutment height, retention choice, splinting, and material cleansability — into an integrated upstream ruleset, finding that roughly 78% of peri-implantitis cases involve inadequate hygiene access driven by prosthetic design.
Design determines cleansability
Source Paper
Influence of Surgical and Prosthetic Factors on Peri-Implant Health or Disease. Clinical Recommendations From a Spanish Society of Periodontology (SEPA) Expert Consensus
When a patient comes back with peri-implantitis, the first thing many clinicians do is ask about the brushing. How often. With what. Whether the interdental brushes were the right size. It is a perfectly reasonable question. It is also, if we are being honest, sometimes a way of not looking too carefully at the emergence profile we prescribed.
The paper that makes this discomfort productive is “Influence of Surgical and Prosthetic Factors on Peri-Implant Health or Disease. Clinical Recommendations From a Spanish Society of Periodontology (SEPA) Expert Consensus,” published in 2026 in the Journal of Esthetic and Restorative Dentistry. SEPA convened fourteen periodontists, prosthodontists, and laboratory technicians in Madrid in 2024, examining how surgical positioning, abutment design, retention choice, and superstructure cleansability affect peri-implant tissue stability. The result is a consolidated ruleset for decisions made before disease appears.
The Data Anchor
The number anchoring the whole document: approximately 78% of peri-implantitis cases lacked adequate hygiene access. In one cited study, 48% of implants with peri-implantitis had no meaningful hygiene accessibility, versus 4% of implants without disease; the positive predictive value for disease in restricted restorations was 65%, the negative predictive value for accessible ones was 82%. The prosthesis frequently determines whether the patient has a fighting chance against their own biofilm.
The recommendations span three domains. On positioning: the implant shoulder belongs 3–4 mm apical to the planned gingival margin; inter-implant spacing below 3 mm significantly impedes hygiene; three-unit splinted prostheses on three implants are roughly twice as likely to develop peri-implantitis as non-splinted designs, with interproximal access as the probable governing variable.
On abutments: heights above 2 mm reduce marginal bone loss (MBL); in patients with thin mucosa a 3 mm subcrestal abutment produced MBL of 0.12 ± 0.33 mm at one year versus 0.95 ± 0.88 mm for a 1 mm epi-crestal abutment; repeated disconnections added 0.3–0.5 mm of bone loss. On retention: screw-retained restorations are preferred; methacrylate cements leave debris in 62% of cases; restorative margins ≤1.5 mm from crestal bone carry an odds ratio of 2.3 for peri-implantitis.
The document notes that disease resolution is more efficient when the prosthesis is modified to improve hygiene access. Some of what we call treatment is, in part, belated design correction.
Key Findings
- Hygiene access is the central variable. Approximately 78% of peri-implantitis cases involved inadequate access; prosthetic design is therefore a modifiable upstream risk.
- Emergence angle above 30° with a convex profile is significantly associated with peri-implantitis in bone-level implants; concave or straight profiles are preferred, particularly in the most apical 2 mm.
- Abutment height above 2 mm is protective, especially in thin mucosal phenotypes where the bone-loss differential at one year approaches eightfold.
- Screw retention removes an established risk factor. Methacrylate cement remnants are difficult to control clinically once subgingival.
- Platform switching and conical internal connections are recommended; the weighted mean marginal bone difference versus non-switched implants was −0.21 mm (95% confidence interval −0.42 to 0.00).
- The limitations deserve equal billing. This is a narrative expert consensus; certainty is mostly low to moderate, MBL is a surrogate endpoint, and design choices reduce risk without conferring immunity.
💡 The Clinical Bottom Line
The practical shift this consensus asks for is attitudinal rather than technical: treating prosthetic design as a biological intervention, not an aesthetic and mechanical decision that happens to precede the biology.
The useful Monday morning habit is three questions at prosthetic delivery: Can this patient clean every unit with an interdental brush? Is the emergence profile concave in the most apical 2 mm? Is there a reason not to use screw retention? None of these adds clinical time. The answers determine whether a future peri-implantitis workup starts with the patient’s brushing or with our treatment records.
Dr Samuel Rosehill is a general dentist with a prosthodontic focus, practising at Ethical Dental in Coffs Harbour, NSW. He holds a BDSc (Hons) from the University of Queensland, an MBA, an MMktg, and an MClinDent in Fixed & Removable Prosthodontics (Distinction) from King’s College London.
Clinical Relevance
Roughly 78% of peri-implantitis cases in the reviewed literature involved inadequate hygiene access, making prosthetic design a modifiable upstream risk factor. Clinicians should specify emergence angles below 30°, abutment heights above 2 mm, inter-implant spacing of at least 3 mm, and prefer screw-retained restorations. The evidence is mostly low-to-moderate certainty and largely associative, but the design decisions that constrain a patient's ability to clean are made at the chair before disease ever appears.
Disclosure: The author has no financial conflicts of interest related to the products or topics discussed in this review. This is an independent summary prepared for educational purposes.
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