by admin | Dec 22, 2008 | Dental Implants, GBR - Guided Bone Regeneration
This is a complex case of first-stage bone regeneration in order to set two implants in the next phase.
There is also an impacted 13 cuspid, at 45º angle, on the vestibular side, that needs to be extracted.
Sinus lift and Bone Split
More than ten years edentulism in this 28year old patient have left an atrophic ridge “V”shaped, with not enough height as to fix implants simultaneously to the sinus lift.
I open a large flap and drill a lateral window on the bone, setting its lower limit at the estimated height from the ridge I calculate from the X-ray.
I push the window into the sinus and press the sinus membrane up. I measure the crestal bone with from the inside with a probe or curettes to confirm weather the implants can be fixed at this stage or not, depending on factors (bone height, width, density).
I estimate that the with and height are not sufficient for now, and with will be narrow for the future, also. So I split the crestal bone with a disk saw and chisels .
I fill the sinus and the ridge crack I opened with 1gr. Bio-Oss and cover the whole graft with a resorbable Bio-Guide collagen membrane. Stitching this flap section back in place, as I will continue with the cuspid extraction. 6 months will be needed to approach the next phase, which is the placement of the implants. Further ridge augmentation may be needed, depending on the bone stabilization.
Impacted cuspid extraction
The cuspid lays at a 45º angle, on the vestibular side, as I have made sure by touch. With a round bur I open a window on the bone at the estimated position I calculate from the X-ray and finger relief touch.
I soon feel the different hardness of the enamel compared to the bone. I widen the window until I see there could be enough space for the crown to come out.
I cut the crown using the same bur and pull it out with pliers and leverage forces.
If the root is not hardly anchored, It can be pulled out by using a large endodontic round section file, #60 in this case.
The patient will have a bridge done in this section. So there is no need for bone graft to prevent resorption. Stitches are used to close the flap in place over the gum.
by admin | Dec 8, 2008 | Dental Implants, GBR - Guided Bone Regeneration, Oral Surgery
This case combines several advanced surgical techniques
- bone split and ridge expansion on both ends of lower jaw
- extraction and immediate implants with simultaneous vertical sinus lift
- wide lateral sinus lift for later implants
A) Bone split and ridge expansion on both ends of lower jaw
First day of surgery. I place implants on the left jaw.
Many years without teeth have left a collapsed, atrophic ridge, both in width and height.
The inverse “V” shaped ridge is not wide enough as to place the narrowest 3.25” implants.
So, I use a radial saw to slit the bone, working the expansion to the spongeus with chisels.
Then, I use a set of expanders, switching them in progressive widths
I place a short 11.5×3.75” at the back , a 13×3.25” and a 15×3.25” angled towards liguo-mesial in order to avoid the mentonian hole and allow for bigger implant length.
Then, it’s time to fill the gap between corticals and implants with Bio-Oss bone graft and cover it with a Bio-guide resorbable collagen membrane fixed by the healing screws.
On the right side there is even a shorter ridge. That means the leverage forces will be greater. I repeat the bone split process an drill carefully with an angle towards lingual, allowing the mentonian nerve to pass by vestibularly. A 3.75×13” implant at the back, and two 3.25×15” in the front.
B) Extraction and immediate implants with simultaneous vertical sinus lift
The second surgery is on the upper right jaw. There is a “one-and-a-half- tooth” space. Too narrow for two regular teeth. Too wide for just one.
Besides, there is a low sinus. The little bone support, even with sinus lift bone graft (less dense), could be a challenge for long term expectancy. So, my decision is to place two implants, with two small crowns in the end.
I first extract a decayed root with a periapical granuloma.
I open up the flap and start the vertical sinus lift with osteotoms, on both 15 and 14 places, starting by the narrowest one.
Note the damaged, thin cortical layer at 14.
Through the perforation, I apply small pieces of collagen sponges mixed with bone graft. Then, I place a 3.25×11.5 on 15, and a 3.75×13 on piece 14.
I cover the defect with Bio-Oss bone graft and a Bio-guide resorbable collagen membrane fixed by the healing screws.
C) Lateral sinus lift for later implants
The upper left jaw needs a wide sinus lift in order to lace implants at a later stage. There is a no residual bone left at all.
I extract the damaged root and open a wide flap.
I drill quite a wide lateral “window” carefully, not to perforate the membrane. At first touch one can appreciate the extreme thinness of the bone here.
While separating the membrane a perforation occurs. I keep separating, since we’ll need a big volume graft to allow the future implants to hold on to.
Then, I cover the perforation with a resorbable Bio-Guide collagen membrane, fill the sinus with almost two grams of Bio-Oss bone graft
and cover the graft laterally with another Bio-Guide membrane, closing the flap on top.
Again, the before and after panorex. Now we need to wait at least six months to place the implants on the left sinus graft.
by admin | Dec 6, 2008 | Dental Implants, GBR - Guided Bone Regeneration, Oral Surgery
Sinus lift surgery is done when there is not enough bone height to fix one or several implants in the upper rear sections of the mouth.
Placement of the implants can be done:
- simultaneously: remaining bone height over 4-6mm, good primary stability of the implants
- six months after the sinus lift surgery: the remaining bone height doesn’t stabilize the implants well enough (under 4-6mm, depending on bone density and with)
This case shows the placement of two implants on the upper left side, immediately after the extraction of two damaged roots that helped supporting an old bridge.
Simultaneously, I proceed to lift the sinus. Six months will be needed for the second stage implant on the graft, 26 area.
I remove the bridge and prepare to extract two bicuspid roots.
I open a flap, place the first implant on 24, carefully drill a lateral window on 26 and break it open into the sinus, pushing the membrane as far up as possible.
I place the bio-oss bone graft inside the sinus, cover it with a lateral collagen resorbable bio-guide membrane .
Then, I insert the second implant on the groove of 25, now that the sinus membrane has been lifted and I can reach maximum height with the implant.
To end with, I fill the small hollow spaces around the implants with more bone graft. I cover them with another piece of membrane and apply stitches to close the flap back in place.
This is the result after the surgery. Implant 24 and the cuspid overlap on the X-ray, but it’s just an effect of the panorex. The healing screws are not completely screwed in place because they have been used to fix the second membrane and cannot fit further in, but it s sufficient.
After a few weeks’ resorption, the screws can be adapted more deeply.
Six months later, the graft will have enough density as to place the third implant.
by admin | Dec 1, 2008 | Dental Implants, Oral Surgery
Sinus lift surgery is done when there is not enough bone height to fix one or several implants in the upper rear sections of the mouth.
Placement of the implants can be done:
- simultaneously: remaining bone height over 4-6mm, good primary stability of the implants
- six months after the sinus lift surgery: the remaining bone height doesn’t stabilize the implants well enough (under 4-6mm, depending on bone density and with)
This case shows the placement of four implants on the left side, upper and lower, simultaneous to the sinus lift. the placement of the lower implants is reviewed in another article.
Several years without teeth on this side has completely altered the occlusal plane compared to the other side .
I open a flap on the gums big enough to approach the bone I want to treat.
The first approach is to drill and expand the crestal bone. Ostetoms are pushed carefully in to prevent the thin membrane that covers the inner side of the from breaking. This gives to signals. One is the bone density. The other is the bone height to the maxillary sinus.
If height, width and density are estimated to be enough as to stabilize the implants, as well as the bone graft, the graft can be introduced through these drillings and no further surgery is needed other than placing the bone graft and the implants.
In this case I estimated:
- Stability was good enough to place 4mm implants
- the leverage forces the implants would receive after load would be high, since the implants were to placed high up compared to the occlusal plane
- the amount and extension of the graft should be big enough as to provide support to these implants
So, I decided to lift the sinus membrane also laterally and insert the maximum bone graft material. A lateral window is open by drilling extremely carefully, not to break the membrane. The implants are placed and their stability is checked. 
Thanks to the window I opened on the bone, the thread of the implants can be seen laterally.
I place the graft around the screws inside what used to be just air a few minutes before. The graft is made of lyophilized animal bone and some minerals. The body uses these graft material to crate self bone progressively. It takes about six months for this new generated bone to have enough strength to support load.
The lateral wall of the sinus is now folded up and above the implant threads, becoming the “ceiling” of the graft. Now we need another “wall” to close the “window” I opened and avoid the graft falling out and being reabsorbed without creating new bone. This is done by placing a resorbable collagen membrane over the lateral side. 
Then, the flap is put back in place and stitches are used to close. They will be removed after 10-14 days, but the longer, the better, since the flap won’t stick to the membrane as it will stick to the bone.
The lower left implants are easily placed a little under the bone margin, to let space for the crown placement, since the occlusal plane is so damaged.
This case will need orthodontic treatment to lift the left teeth back in place, using the implants for anchorage. Once the occlusal plane is aligned, the crowns over the implants will be built.
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