- 116 -
группы
выявила
необходимость
и
оправданность функциональной разгрузки
системы
имплантат-протез
путём
избирательного
пришлифовывания
окклюзионных
поверхностей
зубных
протезов, а также зубов-антагонистов.
Кроме того, наблюдаемое нами
рентгенологически достоверное отставание
процессов
остеинтеграции
дентальных
имплантатов подтверждает известное мнение
ряда исследователей о тесной взаимосвязи
процессов
приживления
дентальных
имплантатов и стояния окклюзионных
взаимоотношений зубных рядов. Вследствие
функциональной перегрузки зоны имплантат-
протез-кость начинается дезорганизация и
рассасывание структурных единиц костной
ткани, в первую очередь трабекул, с
образованием
полостей,
которые
заполняются волокнистой соединительной
тканью
[8].
Вследствие
последующей
резорбции
костной
ткани,
а
также
дегенерации
её
до
уровня
остеоида,
лишённого
минерального
компонента,
возможны микропереломы трабекул и
остеонов [9].
Таким образом, своевременное и
целенаправленное
проведение
избирательного пришлифовывания позволяет
предупредить
развитие
метаболических,
функциональных и структурных изменений в
альвеолярной кости в перимплантотном
участке, что значительно улучшает прогноз
ортопедического
лечения
больных
с
применением дентальных имплантатов.
ЛИТЕРАТУРА
1.
Грудянов А.И. Пародонтология. – М.:
ОАО Стоматология, 1997.
2.
Грудянов А.И. и др. Заболевания
пародонта и вопросы травматической
окклюзии в клинике ортопедической
стоматологии// Новое в стоматологии. -
1999; №4. – С. 3-218.
3.
Дженкельсон Д. Окклюзионные
выравнивания. - М., 1972.
4.
Иванов В.С. Заболевания пародонта. –
М.: МИА, 1998.
5.
Кауфман С., Мусин М. Принципы
формирования окклюзии при реабилитации
функции
жевания
после
оральной
имплантации//
Клин.
имплантол.
и
стоматол. – 1997. – №2. – С. 38-42.
6.
Хватова В.А. Диагностика и лечение
нарушений функциональной окклюзии. – Н.
Новгород, 1996.
Казахский национальный медицинский
университет им. С.Д.Асфендиярова
7. Оноприенко Г.А. Васкуляризация
костей при переломах и дефектах. -
M.:Медицина, 1995.- 216 с.
8. Параскевич В.Л. Диагностика
регионарного остеопороза челюстей при
планировании имплантации// Рос.
стоматол. журнал. - 2000. – N 2. - С. 33.
9. Риггз Б.Л., Мелтон Л.Д. Остеопороз.
Этиология, диагностика, лечение.- M.; СПб.:
ЗАО «Бином», 2000.- 560 с.
Clinical Application of Flexible RPD using Valplast System.
Emeritus Professor.
Dr. Kay, Kee-Sung.
School of Dentistry, Chosun University, South Korea.
Flexible partial is a removable denture
made from thermoplastic resin consisted
of nylon components by the injection
molding system, which is remarkable in
biocompatibility and flexibility.
Valplast resin is a superpolyamide,
invented for making esthetic RPD by
Arpad T, Nagy and Tibor F. Nagy in
1950`s.
When heat the Valplast capsule to
285°C, it becomes flowable easily to
inject.
The flexibility of the resin achieves the
effect of a stress- breaker without
complicated attachments.
- 117 -
The strength of the material and
resistance to chemical breakdown
provides a long-lasting, unbreakable
partial.
By distributing the stress more naturally
in the mouth compared to conventional
partials, the remaining teeth and gum
typically stay healthier longer than with a
conventional partial.
The gum tissue is gently stimulated
under materials and unnatural stresses on
the remaining natural teeth are
substantially reduced.
Advantages of Valplast flexible partials
1.
esthetic point of view
2.
can be made in very thin shape
3.
good flexibility and resistance of
stress
4.
good biocompatibility
5.
less harmful stresses on abutment
teeth
6.
good physiological stimulation
Characteristics of flexible partials.
1.
Usually there are no needs of oral
preparation, such as cutting out the
remaining teeth, except a rest seat in case
of tooth- borne short- span RPD
2.
sometimes enameloplasty can be needed
3.
proper intermaxillary distance of 5 mm
for tooth arrangement is needed.
Indication and contraindication of flexible
partials.
1.
most of the partial edentulous
patients
2.
patients who have allergy to the
denture acrylic monomer
3.
patients who hate to be seen a metal
clasp arm
4.
patients who don’t want a tooth
preparation
5.
patients who break the denture
frequently
6.
old patients
7.
young patients in growing
8.
patients who have periodontal
problems
9.
splinting effect for natural teeth
having a little mobility
Kinds of clasps for flexible partials
1.
wrap around clasp
usually used in bucco-
lingual surface.
positioned in the adjacent
abutment teeth to
edentulous area.
Most commonly used in
free end edentulous cases.
2.
spur
usually triangle shape to
look like a interdental
papilla and placed near
the cervical line.
3.
high spur
in case of having
difficulties in using
normal spur or wrap
around clasp due to the
severe underent on the
abutment teeth in
posterior area.
4.
anchor clasp
it should be extended to
the width of the two teeth
at the anchoring portion.
5.
split clasp
it is used in the abutment
teeth which have a
excessive lateral
inclination that makes
retentive arm to cross the
severe maximum contour
before entering the
undercut.
Major connector of the flexible partials
Maxilla: if there are few remaining teeth,
whole palatine or ¾ of partial area should be
covered.
Mandible: linguoplate in every case
should be made.
Considerations during the delivery of the
flexible partials
1.
the occlusion should be checked
2.
premature contact should be removed
3.
over- pressured tissue should be
checked
4.
over- extended flange should be cut
5.
tightening or loosening of the clasp
should be adjusted
6.
education to the patient is necessary
Comparison of physical characteristics between
methyl metacrylate and Valplast.
Physical characteristics
Methylmetacrylate
Valplast
Specific gravity
1.16- 1.20
1.04%
- 118 -
Water absorption
0.4 %
0.4%
Saturation by immersion
14%
2.2%
Tensile strength (Kg/ mm²)
5-7
8
Compressive strength (Kg/
mm²)
8.6
10.5
Bending strength (Kg/ mm²)
8.5
8-10
Impact strength (Kg/ mm²)
10.5
120- 150
Polymerization (in 6 hrs)
160° F
460° F (injection)
Combustion
Burns
Non- inflammable
Resistance to acids, bases
Weak
Very strong
Decoloration
Possible in time
None
Considerations about the relief.
1.
it is very important to design an
accurate denture and relief according
to the gingiva, abutment teeth and
oral condition.
2.
at clasp region the relief thickness
according to the amount of undercuts
has to be adjusted as little as
possible.
3.
hamular notch or retromolar pad is
relieved slightly if possible.
4.
torus is designed to avoid, but if it is
covered with denture, it should be
fully relieved.
Retento- grip technique.
1.
flexible denture uses both tooth undercut
and tissue undercut to obtain retention in
design.
2.
in most cases, denture retention is
obtained by small parts of abutment teeth
and mucosal tissue.
Repair of flexible denture
1.
in case of missed artificial teeth or
exfoliated natural teeth during using
of flexible denture, extension or
repair of remaining denture is
possible.
2.
relining is possible with only the
same material at process of rebasing
is more simple and results in a better
denture.
Home care
To keep the denture surface clean and
safe from coloration, it must be put in the Val-
clean denture cleaner, denture cleaning solution,
for 15 to 30 minutes every day.
Insertion of the flexible partials
It must be put in a hot water 80° C for 2-
3 minutes and cool it until patients can bear, then
be placed in the oral cavity and be stayed closing
the mouth for a while.
This process releases the molecular
structure of resin and makes the early placement
soft and comfortable so it results in a well
fitting to the oral tissue conditions.
Case presentation
1.
class I
2.
class II
3.
class III
4.
class IV
In conclusion, Valplast flexible partials
offer a premium product with far more benefits
in esthetics, function, comfort, and reduced
chairtime.
ОПТИМИЗАЦИЯ ОРТОДОНТИЧЕСКОГО
ПЕРЕМЕЩЕНИЯ ЗУБОВ С ИСПОЛЬЗОВАНИЕМ
МАТЕРИАЛА КОЛЛАПАН-Л
