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Page Index
Dental Implants Overview
Endosseous Implants
External and Internal hex implants
How and why implants work?
Classical 2 step implant surgery
Stage 2 Uncovering the implant
Immediate implant placement
Sugical implant placement- case presentation
1 step dental imlant procedure
Immediate Load Implants
Indications and risks
Little
bit of history
Many years ago,
my wife was an assistant in an oral surgery office (now she is the excellent dentist working our practice), she would
come home and tell me about an implant placement surgery. This
dental implant surgery would be the talk of the town that day; at least a half of the entire day was blocked off for
a single implant and the implant dentist and staff would get ready the day before.
Nowadays, dentistry implant surgery is as routine as getting a tooth pulled or a filling placed. With some general preliminary diagnostics and evaluation, the patient is ready for
his dental implants.
In many cases an extraction of a rotten or
broken tooth and the dental implant placement occurs in the same visit and leads to excellent integration and prognosis. (The things is, that the bone socket naturally fills with bone after the tooth is
removed, and having the implant already there, just speeds up the process and eliminates unnecessary surgery.) A lot of times,
when patient comes as an emergency and tooth has to be extracted, we would do
the emergency extraction with immediate placement of implant (love doing that and so do the patients).
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Dental Implants Overview
Dental implants
are rapidly becoming a routine procedure in today’s dentistry. In many clinical situations, implants are the number
one choice of restoration for missing teeth. The most commonly used implants are The Endosseous
implants. There are also other kinds of implants in dentistry, but they are used rarely today.
I will try to describe here procedures and use of endosseous dental implants.
Implants in dentistry
is a very fast developing field. That is why there are many different manufacturers producing endosseous implants. The will
differ in shape and form; their available sizes can slightly differ. The most accepted material for dental implants is either
high grade Titanium (Commercial Pure) or Titanium alloy. The titanium alloy implants tend to be stronger than the CP titanium
implants. The bone integration shows no difference to the two different types of titanium.
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Renova Implant
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Endosseous Implants
If you look at the implant
from the side, it resembles a screw. The outer surface of the implant may have different coatings stimulating bone growth,
or it may just have smooth or roughened surface.
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Bicon Implants
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External and Internal Hex Implants
The top part of the dental implant is called Hex. It has a locking mechanism, which may be inside
the body of the implant- internal hex implants, or stick as a platform above the body of the implant-external
hex implants. Also, if you look at the implant from the top you will see the threaded ‘canal’ in the
middle of the hex going down the body of the implant. The future restoration will be seated on the hex and screw tightened
to the implant. It is doctor's preference which type of implants to use. I prefer internal hex implants for
these reasons: they give a better retention for the future restoration, and they can be placed slightly deeper allowing for
more cosmetic restorations.
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Dental implants come in various thicknesses and length. Your anatomy and
bone levels dictate the size of the implant that can be placed. The longer, thicker
implants usually last the longest.
It is each doctor’s preferences to decide which type of implant
to use. However, their basic principle is the same. Endosseous implants or Root-formed implants are the anchors,
which are placed inside the bone of the jaw and substitute the root part of the tooth. You must remember
that implant is just a support for future restoration. Endosseous implants can be used:
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To support single crown for one missing tooth,
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Two or more implants can be used as a support for fixed
bridge restoration and one of best alternatives in restoring missing teeth
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Implants can be used as a retainer of removable dentures
Integration of live tissue with the implant
How and why implants work?
After dental implant
is placed inside the bone, it usually takes about 2 to 6 month for the implant “to heal”. Actually, we are waiting
for the implant to bond with the surrounding tissue – a process known as osseointegration. Osseointegration was a term
coined by a Swedish Professor Per-Ingvar Brånemark in 1952 when he discovered the ability of living tissue
to integrate with titanium. Osseointegration has been described as a direct structural and functional connection
between living bone and the surface of a load carrying implant. During his original research, Prof. Brånemark found a way
of using pure titanium as an anchoring unit and support for a variety of prosthetic reconstructions. The long-term predictability
and success of Dental implants is based on the fact that an active bond between bone and implant is created at the molecular
level. The fixture is not only accepted but also incorporated within the bone.
The
implant procedures
There
are different techniques that can be used for the surgical placement of the dental implant. It depends on
the particular conditions of the case, doctor’s preferences, and dental implant system used. First let's take a
look on a classical 2 step implant surgery, which is the most common technique used for dental implant placement.
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Classical
2 step implant surgery
1. When you come for the surgery, you will be given a surgical
consent form, describing the procedure and possible complications. It is a good time to address any questions
and concerns. After you sign the consent form, you will be anesthetized and surgery will soon begin.
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Edentulous area to be restored by implants
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2. Doctor will make a cut in you gum along the crest of the bone and push it to the sides to access the bone.
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3. Using different sizes of special drills, doctor will drill inside the bone to make a path for an
implant. Doctor will start with thin drills, gradually moving to thicker ones. The diameter of last drill will be slight smaller
than the diameter of the selected implant. Surgical drills have a canal inside its body to allow constant
water irrigation, which is necessary to cool down the bone, preventing it from overheating.
4. Implant is screwed inside the bone. Necessary x-rays can
be taken during the procedure
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X-ray showing surgically placed dental implants
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5. A surgical cover screw is inserted into the top if the implant to prevent bone and tissue to grow
inside the implant.
6. Gum is placed back and sutures are used.
Doctor will give you all necessary prescriptions and instructions. In 7-10 days, you come back for suture removal and follow up. There will be several other follow-up
visits to monitor the healing process until such time that the implant is ready to be restored with
a prosthetic.
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Stage 2 –Uncovering the implant
What happens after dental implant is osseointegrated?
After the doctor has concluded
that implant integration is complete, the dental implant has to be uncovered:
- Local anesthesia is administered.
- A small incision is done in the gum, allowing doctor to unscrew the surgical cover screw.
- Healing cover placed instead of the surgical screw, projects above the gum preventing it from closing over the implant.
Sutures are placed to hold the gum back in place.
- One week later doctor will remove stitches, and after few more days of healing implant is ready for restoration.
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Left dental implant with healing collar
Implants with restoration abutments (posts)
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Immediate Placement Of implant
(Implant Placement into fresh extracted site)
When the tooth has to be extracted, and the implant is a choice
of treatment for substitution of removed tooth, immediate placement of implant into extracted site could be done. There are
a lot of advantages to this technique. In aslassical 2 stage technique described above, after the extraction is done, we would
wait for about 6 month for the bone to build up, and then proceed with the implant surgery. The immediate
placement of implants eliminates this 6 month waitng period, no second surgery required,
healing process of implant (osseointegration) runs as natural process(your body buids up the new bone in the extracted site
where the implant placed. There are some limitations though, when this procedure can be done (severe infection, cortical bone
lose). Your doctor will advise you if the immediate placement of implant is the right procedure for you.
The next implant case presentation describes surgical placement
of two implants, one of them is classical two stage technique, another is the extraction and immediate placement of implant.
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Implants case presentation
53 years old female
presented in the office for exam. Intaraoral and X-ray examination revealed severe decay under the crown
supporting the bridge. The decay was so extensive, that the tooth was unable to be saved. Since the other teeth under the
bridge did not require any urgent treatment, it was decided to cut the bridge, leaving anterior crowns intact (teeth # 20,21),
extract back tooth (#18), and place teeth implants in the area of missing #19 and extracted # 18. Patient accepted treatment
plan and scheduled appointment for surgery. 4.7 mm diameter and 13 mm length internal hex Zimmer implants
were planned to be placed. Patient was explained the nature of the surgery and possible complications. All her questions were
answered.
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X-ray showing Decay under the crown # 18 Intraoral picture of existing bridge |
Patient was anesthetized, and the bridge was cut between crown # 20 and pontic 19. Back part of the bridge was
removed.
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Bridge was cut
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Demolished # 18 ( after bridge removal)
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Incision was made along the crest of the bone between demolished # 18 and tooth #20. Periosteal flap reflected
using periosteal elevators. The remaining roots of the # 18 carefully extracted with luxators to preserve integrity of the
bone.
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Periosteal Flap opened
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Tooth # 18 is removed
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Osteotomy
was performed in the area of planned implant sites. Drills of increasing sizes were used. The widest drill 4.4 mm was used
to make a 13 mm path for the implant.
Each tooth implants is placed in corresponding sites. Hand ratchet is used to screw the implant (with implant
driver) into the place. Control X-ray is taken.
Implant with implant driver placed in the bone |
Same picture from a different angle |
X-ray showing implants in place 
Implant
drivers removed and position of each tooth implant was verified.
Surgical cover screw placed into the tooth implant
Gum placed
in its place and silk sutures placed to hold the gum. Patient is given instructions and due back in the office in one week
for removal of sutures.
One week later sutures were removed and patient is scheduled in
two weeks for the follow up visit.
One Step Implant Placement Procedure
Depending on the particular situation 1
step surgical implant placement technique may be used. Instead of making a line incision and opening
the flap doctor will use the special round knife("tissue puncher") to cut off a round piece of the
gum in the area of projected implant(punch technique). Ostoetomy performed thru this opening, and the implant
screwed directly in. Instead of puting the surgical cover, doctor will place righty away the implant healing color,
having it exposed above the gum line and preventing the gum from closure. Implant remain exposed
and there is no need for the second surgical stage -openning of the implant. This technique is used more and more.
Besides the fact that there is no need for second surgery, the postsurgical discomfort and pain much less than in a 2 stage
technique procedure.
Immediate Load implants
Please come back soon for revolutionary Immediate Load implant restorations
Indications and Contraindications
Generally, any edentulous (toothless) area, having enough bone
support can be an indication for restoring missing tooth with implant. A decision has to be made whether it is a
good idea based on the patient’s requirements and expectations, and on case-by-case bases. The doctor will consider
many things before advising you on one or another treatment options. Even though there is practically no absolute contraindications
for placement of implants, there are few factors that can put it in a high risk situation.
The risk factors are
· Endocrine disorders, such as uncontrolled Diabetes Mellitus, Pituitary and Adrenal insufficiency
and Hypothyroidism can cause considerable healing problems.
· Uncontrolled granulomatous diseases, such as Tuberculosis and Sarcoidosis may also lead to a poor
healing response to surgical procedures.
· Patients with cardiovascular diseases, taking blood thinning drugs and patients
with uncontrolled hematological disorders such as Generalized Anemia, Hemophilia (Factor VIII deficiency), Factor IX, X and
XII deficiencies and any other acquired coagulation disorders are contraindicated to surgical procedures due to poor hemorrhage
control. (In most cases medicine can be stopped for a few days with permission of your medical doctor)
· Patients with bone diseases, such as Histiocytosis X, Paget's
Disease and Fibrous Dysplasia may not be good candidates for implants, because there is a higher chance for the implant to
fail due to poor osseointegration
· Cigarette smoking
· Patients receiving radio and chemotherapy should not do implants within 6 month period of therapy
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