Does a Novel Trioval Implant Connection Lead to Better Marginal Bone Levels Compared to Control at Three Months Post-Surgery?
Introduction
Peri-implant crestal bone remodeling can lead to an expected reduction in marginal bone levels in the first year of function. Several innovative approaches have been proposed to minimize the initial bone loss commonly observed during this period after osteotomy, with the goal of preventing long-term aesthetic and functional compromise.
This pilot study with 10 participants per group aimed to compare the radiographically assessed crestal remodeling of a novel trioval implant to a standard internal hex conical connection at 3 months post-surgery, which is the generally the accepted timeframe for the initial integration period, to derive sample size calculations for a definitive trial.
KEY RESULTS
- Baseline patient and implant characteristics, including mean implant size were comparable between the two groups.
- Mean bone loss observed in the test group was 0.16 ± 0.21 mm compared to 0.61 ± 0.19 mm in control group. Initial bone remodeling was, on average, reduced in the trioval group by 0.45 mm, but as expected for pilot trials, the results were not statistically significant.
- An excellent (ICC=0.983) inter-examiner agreement was attained using a standardized digital methodology, measuring bone change at 0.5 mm horizontally from the implant margin.
CITATION
Presented at the 31st Annual Scientific Meeting of the European Association for Osseointegration (IAO-EA-SIdP Joint Meeting), October 24 – 26, 2024.
Scott J, Jones O, Atkins S, Milner R, Elbarbary S, Oxley C, Bolt R. (October 2024) IAO-EAO-SIdP 2024-808/PO-SU-079 | Does a Novel Trioval Implant Connection Lead to Better Marginal Bone Levels Compared to Control at Three Months Post-Surgery? E-Poster. Clin Oral Impl Res; Volume 35, Issue S28; p292 https://onlinelibrary.wiley.com/doi/epdf/10.1111/clr.14366
REFERENCES
1. Renvert S, Persson GR, Pirih FQ, Camargo PM. Peri‐implant health, peri‐implant mucositis, and peri‐implantitis: Case definitions and diagnostic considerations. Journal of Clinical Periodontology. 2018 Jun;45:S278-85.
2. Velikov S, Susin C, Heuberger P, Irastorza-Landa A. A New Site Preparation Protocol That Supports Bone Quality Evaluation and Provides Predictable Implant Insertion Torque. J Clin Med. 2020;9(2).
3. Yin X, Li J, Hoffmann W, Gasser A, Brunski JB, Helms JA. Mechanical and Biological Advantages of a Tri-Oval Implant Design. J Clin Med. 2019;8(4):1-13.
Authors






Questions
Ask a questioninnovation for innovations sake
A tri-oval connection that can not accomodate attachment of a 1-piece healing collar makes absolutely no sense. The N1 implant has a smooth, anodized neck. If you positioned tht 1mm supra-crestal to provide an undisturbed zone of attached gingiva, following the On-1 principal, you would further reduce bone loss.
A tri-oval connection that can not accomodate attachment of a 1-piece healing collar makes absolutely no sense. The N1 implant has a smooth, anodized neck. If you positioned tht 1mm supra-crestal to provide an undisturbed zone of attached gingiva, following the On-1 principal, you would further reduce bone loss.

The trilobe connection is an old design. I believe that there was some problem with breakage of the implant connection part in the weakest (thinnest) part of the lobes. I do not whether misfit connections with the abutment connector, common to the screw-in installation system, was somewhat responsible for the premature failure of the implants. I suspect that misfit connections might have contributed to the observed breakage, as these and other connectors were not designed to be connected in a misfit way.
I must apologize - trioval connection is not the same as the tri-lobed connection. However, the comments are the same - were these abutment-crown complexes screwed-in or were the abutments screwed-in before the crowns were cemented? This was not clear. If screwed -in, then the dentist will have needed to somehow manage several paths of insertion determined by adjacent teeth, the implant screw channel and abutment connector ... all within the fit-tolerances of the connections (unknown), while adjusting contacts and displacing adjacent tissues. This is tough to impossible for even a single crown, unless the fitting parts are really sloppy.
We have not reviewed the On-1 principal and have provided fixture-level prostheses for both groups (N1 Vs Replace) without using On-1 abutments. All implant-supported prostheses were fitted with Universal abutments, which are fixture-level prostheses.
It is helpful to point out that an N1 implant is a para-crestal or early-subcrestal implant. To our knowledge, no manufacturer or clinician recommendation would suggest leaving the implant 1mm supracrestal. The On-1 concept utilises an abutment fitted at the time of implant surgery to contribute to the supracrestal/transmucosal componentry and is left undisturbed for mucointegration.
Further literature on how the On-1 concept is intended to work can be found here. https://pubmed.ncbi.nlm.nih.gov/33918898/
What are the specific features of the trioval implant connection that differentiate it from traditional designs?

As moderator of comments, perhaps one of the authors would like to respond to the comments.
This is a really good question. In essence, the reduced radius in certain areas can remove pressure on key local anatomical structures such as the buccal plate post-placement. For more detailed information, please see the attached link for literature regarding the trial-oval design. https://pubmed.ncbi.nlm.nih.gov/37855174/
Why not measure bone loss without attached crown andwhy only 3 months?
There are 3 roots causes of implant-abutment misfits related prosthesis (crown) installation that can make the comparison of connection types difficult to interpret. In this experiment researchers may have hve erroneously assumed that they have optimized the fit of their connectors. As well, what were the fit torances of the connectors? If they were different, the possible “more bone loss” may have been due to a sloppier fit of parts rathere than onnector design. Is it not time for manufacturers to disclose the fit tolerances of their parts??https://reversemargin.com/making-the-screw-in-prosthesis-installation-s…
There are 3 roots causes of implant-abutment misfits related prosthesis (crown) installation that can make the comparison of connection types difficult to interpret. In this experiment researchers may have hve erroneously assumed that they have optimized the fit of their connectors.
As well, what were the fit torances of the connectors? If they were different, the possible “more bone loss” may have been due to a sloppier fit of parts rathere than onnector design. Is it not time for manufacturers to disclose the fit tolerances of their parts??
https://reversemargin.com/making-the-screw-in-prosthesis-installation-system-safer/
In reply to Why not measure bone loss without attached crown andwhy only 3 months? by Emil Svoboda
Hi Emil, thank you for taking an interest in our research. The answer to your initial question is threefold: ethics, intended benefit measured, and internal validity.
A radiograph without an attached crown would require additional potentially harmful exposure with no clinical benefit. This study has routinely used radiographs as part of a standardised care pathway, always within IRMER guidance and as per ALARA. This is essential for adhering to the Declaration of Helsinki and is key to gaining Ethical Approval for research in the UK.
In this case, our null is that there is no difference in the radiographic appearance of osseointegration over two implant systems. Three months is consistent with what is generally accepted as the completion of the initial osseointegration period. This corresponds with a clinically driven radiograph that we take as part of standard care.
We do agree that further research at more extended follow-up periods would be interesting and insightful for ongoing crestal bone stability but this was not what our research was designed to assess. More extended follow-up periods are relevant to crestal bone stability but not initial crestal remodelling over the osseointegration period.
As a side note, more extended review periods tend to generate incomplete data due to losses to follow-up and variable periods to subsequent radiographs/clinicians forgetting to take review X-rays. Longer healing periods do, however, give a more global perspective of overall performance over the lifetime of an implant, which warrants the trade-off of completeness of data for certain parameters of interest - parameters of interest in our research were not related to long-term outcomes. In our research, we have presented 100% complete data with zero losses to follow up - this is not the reason for looking at the three-month period, but it illustrates the robustness of what has been presented.
In this case, we feel that we have not made an erroneous assumption. The bone levels cannot be influenced by incorrect connector fit as the study period does not include that with crowns in place. The research does not refer to, or provide any attempt to review the optimisation of prosthetic fit. The radiographs were taken post-surgery and at the impression coping stage.
‘’Also, what were the fit tolerances of the connectors? If they were different, the possible “more bone loss” may have been due to a sloppier fit of parts rather than the connector design. Is it not time for manufacturers to disclose the fit tolerances of their parts??https://reversemargin.com/making-the-screw-in-prosthesis-installation-s…’’
There seems to be confusion around the nature of the research we have presented. There is no potential for bone loss relating to inaccurate connector fit, as the crown was only fitted after the final outcome radiograph for this study.
The radiographs, therefore, represent early healing with the use of healing abutments, with crown-fit radiographs being a method of assessing this over the early healing period to osseointegration.
However, it may be reassuring that original components perform better than nonoriginal ones, as they are developed and tested for optimal fit. Please see the following: https://pubmed.ncbi.nlm.nih.gov/30427953/