Crestal Sinus Lift with Osteotomes: Minimum Height?
This case involves a 75 year old male patient. The question is related to the implant in #16 region. The CBCT showed 5.8 mm bone height from the sinus floor to the bone crest and 8.4 mm bone width bucco-palatally. I placed an ADIN 4.2x10mm implant in the #16 region. An immediate post-operative intraoral periapical radiograph has also been posted.
Initially I used the drills to prepare the osteotomy to the depth of 5mm followed by osteotomes to perform a crestal sinus lift without using any bone graft.
The sinus is not perforated as I confirmed by Valsalva maneuver. Patient was prescribed analgesics and antibiotics for 5 days and is asymptomatic after 1 week of implant placement.
I have the following questions:
1. How much bone height is the minimum required for a crestal sinus lift ? (Literature that I have read states 5mm. Would like to have clinical opinion of colleagues.)
2. How many millimeters can we lift the sinus using crestal sinus lift technique with osteotomes ?
11 Comments on Crestal Sinus Lift with Osteotomes: Minimum Height?
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Jarrett Darrah
2/23/2017
I've read you need 5-6mm and can lift predictably 3-4mm but some people say they can get 5mm. Perfs start to happen when you push 5mm though (from what threads I've read on this blog).
DR MILIND DESAI
2/24/2017
i have done implants with 3 mm bone with 5 mm implant in the sinus,,they are successful after 7 yrs...achieving good primary stablity and following drilling protocol.widening the osteotomy by osteotomes slowly is important
Dr Ashish Bisane
2/26/2017
Nice experience shared sir. Kindly elaborate as to what density bone would you recommend in such cases where in 3 mm bone height exists and a sinus lift is to be done using osteotomes ? Do u prefer preparing the osteotomy to a lesser diameter in such cases so as to achieve better primary stability ?
Thanks for the info.
Richard Hughes, DDS, FAAI
2/28/2017
Why did you place an implant in the # 16 area? This is a third molar area. This ares is difficult to access for both surgery and prosthetics and is of little use.
The minimum vertical bone height needed for an uplift is 4 mm.
The rule of thumb I use to determine the ammount the sinus membrane can be raised is: 2x what you see minus 2 mm.
However, I do raise more than this due to graft shrinkage.
Dr. Ashish Bisane
2/28/2017
The implant was placed in maxillary right first molar region.
#16 is mentioned as FDI system of tooth numbering.
Ernesto Bruschi
3/1/2017
The point is that it all depends on the PNR angle (much like lateral windows sinus lift) and how much bone is on the inner vault. The amount of bone between the crest and the lower part of the sinus is not really important, as long as you have at least 4mm and a good PNR angle with bone on the palatal vault. If the osteotomes are initially directed towards the PNR and the palatal vault, a great amount of stable intracortical space can be created and you can insert a 10-13mm implant. If the osteotomes are directed straight you'll get 3mm easily; but the same amount of lift can be obtained directly with the tip of the implant by underpreparing in lenght, or with piezosurgery.
Reg O'Neill
3/1/2017
This technique we are familiar with is dependent on herniating a volume of bone into the antrum, as such it is reliant on preparing an osteotomy short of the floor of the antrum and making a greenstick fracture upwards carrying the unprepared bone at the end of an osteotome. Tatum would have been the first to do this and he and Misch taught the technique, written up by others in the literature. Your CT image shows a sizable septa with height, I guess this allowed you to drill to 5mm. If the bone is only 5.8mm in height you would not drill to 5mm and then use osteotomes - more risk of lining perforation and inadequate volume of bone at the end of the osteotome. I am doubtful of the valsalva test of lining integrity. When the technique herniates bone, the floor of the site can be probed. Of course if the ostium is not patent for any reason the valsalva would not be expected to move the lining. All in this looks like a very competent placement and should be successful long term for a first molar. Heights lower than 5mm are much more challenging for implant stability and the extra height developed is not contributing to this initial situation.
Dr. Ashish Bisane
3/1/2017
I agree 5.8 mm bone height was a good situation in this case to begin with. And it did help in achieving a good primary stability while placing a 10 mm long implant.
In any other situation where the bone height is lesser than 5 mm, how short of the sinus floor would you suggest to drill ?
I assume drilling upto 2 mm short of sinus floor and then using osteotomes to lift the sinus would be a safer idea.
Any suggestions and opinions are welcome and appreciated.
Reg O'Neill
3/1/2017
I would not drill the posterior maxilla, period. Create an osteotomy condensing and expanding, then flat ended osteotome to gain additional height. Less than 5mm of floor height is the tipping point towards a graft (lateral wall approach) and of course you can consider implant placement and simultanious graft at less than 5mm of bone height. How far and how much like most implantology is dependent on experience and judgement but we all should start using these techniques when you have plenty of height and don't need too many miracles at once!
Dr. Ashish Bisane
3/1/2017
Apparently the discussion was started for the same reason.
So as to know what all experiences people can share.
We have experiences from where people have done osteotome sinus lift with 3 mm bone height to those who advocate 4 or 5 mm bone height to work safely.
Also 4-5 mm sinus lift using osteotome was agreeable to many of the members participating in the discussion.
Ernesto Bruschi
3/1/2017
In my opinion is that it all depends on the PNR angle (much like lateral windows sinus lift) and how much bone is on the inner vault. The amount of bone between the crest and the lower part of the sinus is not really important, as long as you have at least 4mm and a good PNR angle with bone on the palatal vault. If the osteotomes are initially directed towards the PNR and the palatal vault, a great amount of stable intracortical space can be created and you can insert a 10-13mm implant. If the osteotomes are directed straight you'll get 3mm easily; but the same amount of lift can be obtained directly with the tip of the implant by underpreparing in lenght, or with piezosurgery. Alternatively, a shorter implant (4-6mm in lenght could be used).
