Dentistry/Molar implant too narrow (3.3mm)?
QUESTION: Three weeks ago an endodontist placed a Straumann SLA bone level implant in the first molar location (tooth no. 14). I learned afterward that the implant is 3.3mm wide by 8.0mm high. The Straumann Implant Selection Guide says Caution: the narrow crossfit 3.3mm wide implant is not recommended in the molar region.
Six months before the implant placement the endodonist had extracted the molar. He attempted an implant placement at that time with I believe a standard-width implant but decided the site wasn't suitable for immediate implant placement. He added bone graft material and sutured the opening closed.
You can see from the x-ray there is a large space between teeth 13 and 15. The x-ray was taken the day of the implant placement.
In case this is relevant, I have two successful 4.1mm-wide implants in locations 4 and 5. I have had those for four years. I mention this in case they indicate that the width of my upper jaw bone should be wide enough to accommodate at least the standard 4.1mm wide implant.
The abutment and implant crown are scheduled to be put on 6 months from now.
ANSWER: Hi Michael,
Immediate implant placement in molars is very tricky because the implants tend to slip to one of the extracted roots, whereas the ideal position is in the middle. So in a way, it is good that your dentist did not succeed the first time. On the other side, this could have been successfully done with different implant system, with or without adding bone graft. Straumann implants are not suitable for immediate placement in molars due to their thread design and shape. I would suggest you advise the dentist to add another system for the purpose.
Ending up with 3.3mm implant for a molar is not optimal, because you are at higher risk of fracture of the thin implant wall at the implant-abutment connection level. The are a few reasons why the dentist have chosen narrow diameter implant, but the fact is that it could have been avoided. You still have good chances for success if smaller size crown is made, in order to reduce the occlusal load. This is my suggestion.
If you are aiming for ideal results, you can have the implant replaced. At 3 weeks, removal of the implant is still possible.
Another suggestion is in the future, if you need implants, to use the following guide for choosing a professional:
2) General dentist with interest in periodontics
3) Oral surgeon
4) General dentist with interest in oral surgery
7) Pediatric dentist
Dr Veselin Shumantov
Center for Advanced Dentistry
---------- FOLLOW-UP ----------
QUESTION: Thank you for your expert and detailed reply. I learned one possibly crucial new fact after I asked the original question. The interdental space between tooth 13 and tooth 15 is 6.5 mm, which I'm told is a lot less than the usual space in that region. Does the relatively narrow space justify using the narrow 3.3 mm implant, or would a standard 4.1 mm implant still have been the better choice? (In the perpendicular dimension, the ridge width is plenty wide enough to accommodate the 4.1 mm implant.)
The best choice is to create the optimal space for standard molar size implant and crown by orthodontic treatment. This way, symmetry with the right side molar can be achieved, as well as more security with the long-term stability of the implant restoration. Material fatigue should always be considered; it surely will occur later with standard diameter molar implant.
However, often patients are not willing to go through orthodontics due to cost or time factors. In this case, placing 3.3mm implant for molar tooth replacement is acceptable alternative, as long as the patient understands what the trade-off is.