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Abstracts of Lectures
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| 1. Is osseointegration essential for implant orthodontics? |
| Dr. Shigeru Saito |
Since many types of implants have been commercially available
for orthodontic anchorage, each clinician have to pay attention
to the following factors such as implant materials, implant size,
implant site, expected loading term, magnitude of expected orthodontic
load, periodontal conditions and age of the patient.
On the other hand, many animal studies have been reported in the
areas of implant-anchored orthodontics. The osseointegration between
titanium implant and the surrounding bone are demonstrated to be
essential for skeletal anchorage in most studies. However, we sometimes
feel inconvenient for tight osseointegration at the time of implant
removal, when bone of the implant site are very compact or the
prolonged retention of the implant has occurred. On the contrary,
insufficient osseointegration often cause loosening or failure
of the implant.
According to my Beagle studies, the osseointegration between titanium
implant and surrounding bone could be changed due to implant size,
implant site, duration of the implantation, and even age of the
dog. Many clinicians understand that the osseointegration in the
maxilla is less than those in the mandible in general. The osseointegration
with large implant is greater than those with small implant. However,
most clinicians do not necessarily pay attention to the loading
timing after implantation.
This presentation will demonstrate the osseointegration with different
type, size and site of the titanium mini-screw and time-course
study of mini-screw for osseointegration using adolescent, adult
and aged Beagle dogs. |
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| 2. Biomechanical considerations to
the screw system |
| Dr. Kim, Tae-Kyung |
Recently the screw system has become an
essential part of daily orthodontic practice, especially
in Korea. We implant screws and apply force to the screws
in our clinic almost everyday, but we have little idea about
the force system. We have a tendency to think skeletal anchorage
as just strengthening the anchorage.
At the presentation I’ll explain the force system of
cases using screws. Actually my screw cases are classified
into 4 groups from the biomechanical viewpoint. The features
and examples of each group will be discussed.
The outline of each group is summarized as follows.
| ¡@ | 1. 1st group:
This group has a single tooth or some teeth involved
as an active unit and screw(s) as a reactive unit. |
| ¡@ | 2. 2nd group: This kind of approach
is most popular in using screws. This group has the whole
arch as an active unit and screw(s) as a reactive unit.
We can explain the force system, assuming the active
unit as a unique deformable body, not a rigid body. The
features of force system will be illustrated. |
| ¡@ | 3. 3rd group: Like the 2nd group,
this group has the whole arch as a deformable active
unit and screw(s) as a reactive unit. But there are internal
forces in the active unit. We might divide the group
into two sub-groups. If the resultant of internal force
and the forces to the screw(s) are absolutely consistent
to treatment goal, we call it absolute consistency. And
in case of relatively consistent to treatment goal, it
would be relative consistency |
4th group: All the above 3 groups are basically a statically
determinate system, but this group has the screws used in the
statically indeterminate way. Clinically I use the appliance
what is called “skeletal transpalatal arch”. The
specific features of skeletal TPA and
clinical experiences will be presented. |
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| 3. Verification of effectiveness of
implant anchorage in orthodontic treatment |
| Dr. Isao Koyama |
Success or failure of the traditional edgewise
treatment depends on careful consideration to anchorage for
tooth movement. Thus, patient compliance is essential and
greatly affects treatment outcomes. No matter how much knowledge
of orthodontic science we orthodontists have, we may not
achieve good treatment results, which also depend on our
technique to elicit patient cooperation.
Further more, the step of anchorage preparation that must be
incorporated into the traditional edgewise treatment increases
the time and complexity of treatment. Reactions from headgears
and elastics must also be considered and controlled, further
complicating the treatment.
The use of implant anchorage simplifies orthodontic treatment
by sparing us the need for patient compliance and the complexity
of treatment.
Case treated with the conventional technique and those treated
using implants will be compared to verify the effectiveness
of implant anchorage. If time permits, a new implants system
currently under development will be introduced. |
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| 4. Variable attachments on the screw
head |
| Dr. Sung-Hyun Kyung |
Recently, the screw implants are widely
used to enhance orthodontic anchorage. However the failure
rate is still high especially when the screw implants are
placed over thin alveolar bone or when the patient is a growing
child. The mini plates from Dr. Sugawara and Dr. Chung show
better stability because 2 to 3 screws are used for fixation.
But the plates need the help of oral surgeon for surgical
procedures of insertion and removal.
Another problem of screw implant is the limitation of force
application. Because the head is designed to apply elastomers
only it is difficult to generate a moment. Dr. Chung inserted
round wire in his C tube and Dr. Costa and Dr. Maino designed
a slot on the screw implant head so that the rectangular wire
can be engaged to overcome this limitation.
As the orthodontic procedure is so complicated the operator
needs various types of head designs for the individual situation.
However not so many screw designs are available on the market.
In this presentation, the splinting method to increase the
screw stability and the use |
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| 5. Distalization of Maxillary and
Mandibular Molars in Adults with the Application of Skeletal
Anchorage System (SAS) |
| Dr. Junji Sugawara |
| The Skeletal Anchorage System (SAS) consists
of titanium anchor plates and monocortical screws that are
temporarily placed in either the maxilla or the mandible,
or in both, as absolute orthodontic anchorages. Distalization
of the molars has been one of the most difficult biomechanical
problems in traditional orthodontics, particularly in adults.
However, it has now become possible to distalize the molars
using the SAS and to improve anterior crossbite, upper protrusion,
crowding, and asymmetric dentition through such distalization
of the molars without having to extract the bicuspids. In
this symposium, I will focus on our clinical studies about
distalization of the molars and present typical cases treated
with the application of SAS. As the results of our clinical
studies, the average amounts of distalization of the mandibular
and maxillary first molars were 3.5mm (range: 1.0mm-7.1mm)
and 3.5mm (range: 2.1mm–6.3mm) respectively at the
crown level. In addition, most of the molars were translated
distally in accordance with the established treatment goals.
Thus, nowadays, the SAS becomes an indispensable modality
in modern clinical orthodontics. |
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| 6. Easy and effective orthodontic
therapy with a brand new bone screw as anchorage |
| Dr. James Lin cheng-Yi |
Several temporary osseous anchor systems
have been introduced into the market as orthodontic anchorage
during recent years. Among these, the bone screws seemed
to be more popular and widely accepted by orthodontists.
Because bone screws offer several advantages over the other
systems: smaller fixture, easier surgical procedures and
less trauma, lower cost and risk, and more clinical indications
and implant sites. However, current commercial available
bone screw systems are unable to bear heavy orthodontic loading
and thus loosen and break easily. For the purposes of bearing
heavier orthodontic forces and reducing the loosening, break,
and failure rate of bone screws, we developed a new bone
screw system called “Orthodontic Mini Anchor System
(OMAS)” . The OMAS bone screw is made of pure titanium
alloy. It has three different diameters (1.5, 2.0 and 2.7
mm) and five different lengths (7, 10, 12, 14 and 17 mm).
The OMAS is designed for multi-purpose usages. One of its
major advantages is its stronger body design and deeper threads
for a better mechanical retention and the ability to bear
heavier forces. Also, It can be used in either a non-tooth
bearing site, such as the zygomatic buttress and the mandibular
buccal shelf, or at a tooth bearing area, such as the interseptal
bone between teeth.
The OMAS bone screw offers many advantages over other bone screw systems:
1. More bone screw sizes available for different purposes.
2. Specially designed for better cleaning and easier application of orthodontic
accessories during orthodontic treatments.
3. Stronger body design and deeper threads for a better mechanical retention
and bearing of heavier forces. |
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| 7. Bone screw based orthognathic orthodontics:
beyond the limits |
| Dr. Eric Liou Jein-Wein |
| The Newton’s 3rd Law, action equals
reaction, dominates most of the treatment results in orthodontics.
Orthodontists have been struggling badly against this Law.
By using teeth to move teeth, orthodontics confines itself
in orthodontic effects. In most circumstances, orthodontics
is nothing but the “orthodontic” orthodontics.
By using bone screws to move teeth, orthodontics is both “orthodontic” and “orthognathic”.
The bone screws based “orthognathic orthodontics” is
a new territory of orthodontics. The orthognathic orthodontics
uses bone screws not only for preventing loss of anchorage
but also for creating anchorage in the anterior-posterior
direction, which allows a maximal or even better correction
of dentoalveolar protrusion than orthognathic surgery. The
orthognathic orthodontics uses bone screws not only for intruding
molars but also for intruding the entire dentition, which
allows a “slow” LeFort I impaction/ en masse
maxillary intrusion and forward and upward rotation of mandible.
The orthognathic orthodontics uses bone screws for orthopedic
protraction of maxilla. The orthognathic orthodontics uses
bone screws for vertical distraction osteogenesis of alveolar
process. The bone screws based orthognathic orthodontics
has gone beyond the limits of conventional orthodontics. |
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| 8. The distalization of lower molars
used the implant anchorage |
| Dr. Hideharu Yamaguchi |
| In adult patients, it is very difficult
to move the lower molars distally for establishment of Class
? molar relationship in Class ? case. In the edgewise method,
we sometimes use the intraoral Class ? elastics for the distalization
of lower molars. Unfortunately, this method is unable to
establish steadily and certainly without patients’ cooperation.
Implants placed at the buccal cortical bone of mandibular
third molars were used as an anchor for the distal movement
of the second molars, first molars and lateral teeth in the
mandible respectively. About 100gr of force was applied unilaterally
with 3mm light nickel-titanium closed coil spring (sentalloy,
Tomy International) between the implant and each molar. During
molar distalization, implants were remained stationary at
the same position, and during lateral teeth and incisor retraction,
the implant-supported molar position was stable. This method
are useful for stationary anchorage and are useful for maximum
anchorage in the edgewise treatment. Implants provide the
ability to establish stable anchor, or absolute anchorage
without patient cooperation. Such implants would be great
benefits for orthodontists in the near future. |
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| 9. The Design of Force System for
the Microimplant and Miniscrew in Clinical Orthodontics |
| Dr. Frank Chang Hsin-Fu |
The main goal of orthodontic treatment is
to establish a good and stable occlusion for the patients
and also to improve their facial esthetics. A correct diagnosis
and a complete treatment plan are very important for achieving
the goal.
A complete treatment plan should include the mechanical plan,
especially the design of force system for every individual
case. To analyze the force system for the straight wire system
is quite difficult and complex and this is why very few orthodontists
pay attention to it. However, this neglect will sometimes cause
the treatment become complex and will take longer treatment
duration when the cases are difficult.
In recent years, the development of microimplant and miniscrew has made the analysis
of force system for orthodontic treatment much easier and simpler and have enormously
shortened the treatment duration. Ten cases treated with microimplant, miniscrew,
and miniplate will be presented to demonstrate their huge influence in the development
of future orthodontics. |
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| 10. Anchorage control using Miniscrew
implants |
| Dr. Young-Chel Park |
Controlling Anchorage is one of the critical
aspects of orthodontic treatment. On account of the limited
anchorage potential and acceptance problems of conventional
intraoral and extra oral aids, bone anchorage system has
been introduced to provide absolute orthodontic anchorage.
Miniscrews has many advantages and wide range of clinical applications
compare to other skeletal anchorage system and the possibility
of orthodontic treatment is increased without performing extraction
of teeth and orthognathic surgery. Furthermore, treatment time
is also significantly shortened.
Clinical cases that were treated by using miniscrews as an
orthodontic anchorage will be presented and the use of miniscrew
implants will be described. In addition, new orthodontic mini-implants
and biomechanical considerations will also be discussed. |
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| 11.
Has the use of intraosseous anchorage changed the possibilities
in orthodontics? |
| Dr. Birte Melsen |
| An increasing number of intraoral extra
dental anchorage systems have been introduced over the past
decade starting with the palatal implant. Some of these are
loaded immediately some are left for osseo integration. The
various modules are used as anchorage for a large variation
of tooth movements. Some of the anchorage modules are used
instead of extraoral anchorage, some in patients where no
other possibilities were available. The lecture will survey
the use of a new type of anchorage, going into details with
advantages and disadvantages of the different types as well
as discussing the tissue reaction to various modes of loading.
Finally the question regarding immediate or delayed loading
will be elucidated. |
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| Copyright© 3rd
Asian implant orthodontic conference All Rights Reserved. |
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