135
References:
1.
Алимова
,
Д
.
М
., and X.
П
.
Камилов
.
Повышение эффективности
лечения рецидивирующего афтозного стоматита с применением озона.
Diss, автореф. дне... д. ф. н.
–
Ташкент: ТГСИ, 2018.
–25–
41 с, 2018.
2.
Ибрагимова, М. X. "Поражения слизистой оболочки полости
рта и
пародонта при патолопш гепатобилиарной системы.” Монография.
Ташкент (2020).
3.
Алимова, Д., Абдуллаева, М., Юлдашева, Н., & Таджиева, К. (2021).
Оптимизированные подходы к комплексному лечению пациентов с
хроническим рецидивирующим афтозным стоматитом
. Stomatologiya, 1(1
(82)), 53–56.
4. Amrulloevich, gafforov Sunnatullo, Abdullaev Shokir Ruzievich, and
GAFFOROVA SEVARA SUNNATULLOEVNA. "Clinical and Laboratory Method for
Assessing the Effectiveness of Diagnosis and Treatment in Patients with Chronic
Recurrent Aphthous Stomatitis Against Infectious Pathologies of the
Genitourinary System.” JournalNX6.06 (2020): 117-127.
5. Khabbazi, Alireza, et al. "A comparative study of vitamin D serum levels
in patients with recurrent aphthous stomatitis.” The Egyptian Rheumatologist
37.3 (2015): 133-137.
6.
Житкова, JI. A., et al. "Современные аспекты этполопш, патогенеза,
клиники, диагностики и лечения хронического афтозного стоматита.”
Здравоохранение
Дальнего
Востока
1.75 (2018): 44-46.
THE CAVITYCONFIGURATION FACTOR
’
S (C
-
FACTOR) INFLUENCE ON THE
EFFICIENCY OF MARGINAL SEALING OF COMPOSITE MATERIALS IN DIRECT
DENTAL RESTORATIONS
Irisboeva F.F., Nematillaeva Z.Sh. group.
Supervisor: Kayumova V.R.
Tashkent state dental Institute, Uzbekistan
Relevance
. In modern dentistry Configuration Factor has just recently
gained popularity with worth in direct restoration’s initial polymerization stress
assessment. In cavities with high C-factor values, the impact of polymerization
stress and shrinkage are especially noticeable.
Purpose of the study.
To determine the role of the c-factor in the
polymerization shrinkage and stress.
1. To identify preventative methods for polymerization-related faults.
2. To consider approaches to lower the value of the configuration factor.
Polymerization, polymerization shrinkage, and polymerization stress were
all introduced with the advent of composite filler materials, which lowered the
quality and longevity of composite tooth restorations.
136
Materials and methods. The polymerization reaction causes the substance
to transition from a liquid to a solid state, resulting in the curing of polymeric
materials. As a result, polymerization shrinkage processes occur, which is the
primary cause of most difficulties, such as postoperative sensitivity, filling
leakage. Shrinkage during polymerization, which occurs during the material’s
curing, causes tensions in the cavity, known as polymerization stress.
When the material is still brittle and easily distorted, shrinkage is at its
maximum, but monomers are not crosslinked. The substance becomes stiff as the
monomers crosslink (form bonds). The rate of shrinkage is slower at this point,
but the stress level is significant. As a result, polymerization shrinkage is the
percentage reduction in the volume of the material during the polymerization
reaction compared to the original.
The following are some elements that lead to the incidence of these stresses:
1. The cavity’s geometry, which is primarily defined by the "configuration
factor.
2. The composite material’s constitution;
3. is related to the previous factor.
The C-factor index was calculated by a group of American scientists in 1987
for various types of cavities. The C-factor is the ratio of the number of composite
material surfaces attached to the cavity walls to the number of free surfaces,
which is one of the key stress metrics induced by polymerization. Given that the
less bonded surfaces and the more free walls, the less polymerization shrinkage
and polymerization stress, experts propose preparing the walls to minimize the
C-factor rather than using the "biological expediency" method. As a consequence,
the less contact the adhesive layer has with the hollow walls, the less
polymerization stress develops in the adhesive layer.
We may obtain the following numbers using the formula above, depending
on the type of restoration: class IV cavities C=0.5, class III=1, , class II=2, class I=5.
Results and discussion. Several clinical trials of Class V restorations have
found that composite materials that generate a lot of stress increase the risk of
marginal gaps
[1]. Several approa
ches to minimize the c-factor value have been
identified to reduce the risk of gap formation in cavities when it is unable to shift
the resulting stresses by the surrounding tissues.
Modern methods for lowering the configuration factor and stress levels.
1. Small amounts of restorative material. Clearly, the smaller the material
part, the lower the stress force during polymerization. As a result, the first
amounts put on the restoration’s bottom should be minimal.
2. Small thickness of the composite material layer. Creation of a shock-
absorbing layer from a low-modulus flowable composite as a liner lining with a
thickness of not more than 1-2 mm
[2]
3. “Soft start”. For the first 10 seconds, low-intensity light is provided,
followed by full strength for 20 seconds. The gel phase has been lengthened a
little.
137
4. Technique of delayed cure. The initial layer, say 1 mm, is polymerized for
3-5 seconds using this process. Then, over the next 20 seconds, a second layer is
added and polymerized.
5. Use of materials that do not cause polymerization stress during curing –
SDR, bulk fill
[2]
6. During preparation, change the shape of the cavity into a plate-like shape
rather than a cup-shaped one.
Conclusion. Standard preparation (according to G.V. Black) produces a
cavity with a C value of 5 in cavities of classes V and I, and a C value of less than 1
in cavities of class IV. Polymerization shrinkage and polymerization stress are
maximum in cavities of classes V and I, and vice versa in class IV, according to the
C-factor principle.
References:
1.
Шукурова
У
.
А
.,
С
.
С
.
Гаффорова
, and
С
.
А
.
Гаффоров
.
«Пломба
ашёларпнпнг
он
13
бушлиги
ту
1
ц
1
маларпга
,
сулак
таркпбпдагп
биокимёвийва
пммуно
-
мпкробполоппс
омплларга
таъспрп»
. Stomatologiya
1 (2020): 60-65.
2. Melkumyan, Timur V., Kamola D. Makhamadaminova, and Erkin Kh.
"Clinical and Experimental Evaluation of the Effectiveness of Softstart
Polymerization in Dental composite Restoration.” International journal of
Biomedicine 2.3 (2012): 242-5.
3. Sunnatulloevna, Gafforova Sevara, et al. "Comparative Evaluation of
Adhesive Microbial Colonization of the Oral Cavity to Various Filling Materials."
Group 100: 40.
4.
Эргашев, Б., Курбанова, 3., & Наврузова, Ф. (2022). Современные
подходы к дентальной имплантации и реставрационной стоматолопш.
Актуальные проблемы стоматолопш и челюстно
-
лицевой хирургии, (1),
825-
827.извлечено от
https://inlibrary.uz/index.php/actual-dentistry/article/
view/14471
5. Melkumyan, Timur V.; Anjela D. Dadamova, and Khaidar P. Kamilov. "The
influence of a hemostatic agent on adhesion strength and microleakage of
composite resin restorations." IJBM (2018): 355.
6.
Мелькумян, Т., Каххарова, Д., Камилов, Н., & Дадамова, А. (2016).
Время экспозиции адгезива как фактор срока службы композитной
реставрации. Stomatologiya, 1(1 (62)), 27
-31.
7.
Мелькумян, Т., et al. "Экспериментальное обоснование
эффективности предварительного нагрева композитного материала при
реставрации зубов." Stomatologiya 1.3 (72) (2018): 10
-12.
8.
Семенов
В.M., and T. II. Дмитраченко. "Самостоятельная работа
студентов медицинских университетов как неотъемлемый принцип
подготовки высококвалифицированного специалиста." Главный редактор:
проф. АТ Щастный Редакционная коллегия: проф. НЮ Коневалова, О
.
А
.
Сыродоева, проф.
(2017): 122.
