Paper ID S004 : Patient Reported Outcome of immediate loaded mandibular 2-implant overdentures retained by magnetic attachments: 3 years follow-up

It is really interesting clinical study of mandibular 2-IOD. Please explain the manufacturer and size of implants and magnetic attachments used in this study. Also Many clinical study indicated that the retentive forces of magnetic attachments were lower than for the other ones. Did the patients express satisfaction to the retentive forces of magnetic attachments in the mandibular 2-IOD?

Dear Dr. Chikahiro Ohkubo
Thank you very much for your question.
The implants and the magnetic attachments that we used in this study is as below:
Implant: Nobel Speedy Groovy RP φ4 × 10–18 mm, Nobel Biocare, Gothenburg, Sweden
Magnetic attachment: Manufacturer: Magfit, Aichi Steel Co., Aichi, Japan
Height: 3.0, 4.0 or 5.5 mm(depend on patient’s thickness of the soft tissue)
Diameter: 4.7mm
We were using a torque of 25-30N, flapless surgical procedure.

As you said, many studies showed that the retentive force of magnetic attachments is lower than the other ones. However, almost all the patients had no complaints about the retentive force in this study, which indicates that even though magnetic attachment’s retentive force may be lower than the other ones, it is still good enough to retain a mandibular 2-IOD, and patient’s satisfaction can be significantly increased.

Thank you very much for good presentation. Please let me know about Fig 5, why is the OHIP score of IL group increasing, in 2y after implant placement?

Dear Dr.Yasunori Suzuki

Thank you for your question and deeply sorry for replying you this late.

Actually, some of the patients had complains about their upper jaw dentures, and some of them had the magnet detachment from the denture base at the time point of second year assessment.
Because OHIP only captures negative impacts and the sample size is quite limited in this study, very few complains can influence the result apparently.
The magnet detachment from the dentures base happened in the immediate loading group may caused by the difficulty of keeping the dry environment when piking up the attachment right after the surgery. The resin surface may be polluted by blood more easily than the conventional group.
By the above, the OHIP score increased in 2 years after implant placement in my opinion.

Thank you!