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NEW OPPORTUNITIES OF DIRECT RESTORATIONS FROM
THE POSITION OF BIOMIMETICS
Khakimova Sh.Kh.
group 308A. Facultyof Dentistry,
Tashkent state dental Institute
Supevisor:
Alimova S.Kh.,
Assistant of the Department of Therapeutic Dentistry, Tashkent state dental
Institute, Uzbekistan
Relevance of the study:
Advance in the modern adhesive restorative
materials, understanding of biomaterial-tissue interaction at the nano and
microscale further enhanced the restorative materials’ properties (such as color,
morphology, and strength) to mimic natural teeth. In addition, the tissue-
engineering approaches resulted in regeneration of lost or damaged dental
tissues mimicking their natural counterpart.
The aim of the present study is to review various biomimetic approaches
used to replace lost or damaged dental tissues using restorative biomaterials.
Materials and methods:
systematic review of articles.
Discussion
. The phrase “biomimetic” was coined by biophysicist /
biomedical engineer Otto Schmitt in the 1950s and refers to the study of multi-
disciplinary mechanisms and biologically produced materials to design novel
products to mimic nature. Biomimetic is derived from Latin word “bio” meaning
life, and “mimetic” is related to the imitation or mimicking biochemical process
with inspiration from nature. While restoring the damaged part of teeth, factors
such as hues, shades, intra-coronal anatomy, mechanics, and position of teeth in
the arch should be considered to respect the biomimetic principles. Dental
composites are presently the direct restorative materials that best accomplish the
requirements of tooth conservation, outstanding aesthetics, and durability.
Strength. Elastic modulus (EM) is considered to be an intrinsic
characteristic of materials and it gives a clear picture about the stiffness of
materials. Ideally, the EM intrinsic characteristic of dental restorative materials
should be harmonized with tooth hard tissues to facilitate uniform sharing of
stresses in the region of tooth-restoration interface during the functional
masticatory load. The gross discrepancy of EM across the tooth-restoration
interface may enhance the probability of fracture of remaining tooth structure. In
addition, tooth-restoration bonding may fail leading to microleakage and
secondary caries. The EM of dentin and enamel has been reported as 14-38 GPa
and 72-125 GPa respectively. Therefore, an ideal dental restoration can be
produced using a combination of two different dental restorative materials with
the EM closely matching to the EM of enamel and dentin.
Surface hardness (SH) of the restorative materials is determined so as to
find their resistance to permanent surface indentation, which indirectly predicts
the abrasion resistance and polishing ability of materials during their service in
the oral environment. Ideally, the SH of restorative materials should closely match
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to the hardness of enamel since surfaces of restorations are directly exposed to
masticatory forces and moist atmosphere such as the tooth enamel. Therefore,
restorative materials with lower SH are more susceptible to abrasion resulting in
surface wear, porosity and eventual failure. The tooth enamel is an extremely
hard tissue. The SH of tooth enamel ranges from 2.23 to 7.18 GPa and dentin
ranges from 0.71 to 0.92 GPa.
Color. Color has no material existence. To observe it, we need three
elements: light as a physical stimulus, the eye asa receiver, and perception as an
individual factor. Albert Henry Munsell divided color into three main aspects:
Hue, Chroma, and Luminosity (Value).
Hue: The degree of mixture of the three primary colors; in simple language,
the name of the color, for example, red, yellow, or blue. Chroma: The degree of
color saturation; pure colors have a high chromaticity and weak colors have a low
chromaticity. Value: The degree of color brightness; the whiter the color is, the
more Value it has, and the darker the color is, the less Value it has.
Just as the natural tooth has two optically distinct layers, while reproducing
teeth we use several layers as well. While layering esthetic materials, we
recognize three layers: the inner layer (In), the external layer (Out), and the
intermediate layer (Mid).
There are five color shades that form a natural tooth; the combination of
these colors enables production of an incredibly extensive chromatic range.
Yellow/Orange: Dentin, White: Enamel and internal enamel characteristics Blue:
Free enamel opalescence Amber: Opalescence, counter opalescence, and various
enamel and dentin characteristics. Modern RDCs kits comprise several shades and
opacities for the corresponding translucency and shades of enamel and dentin
that facilitate the clinician to provide highly aesthetic restorations to patients.
Conclusions
: Thus, the biomimetic approach in direct composite
restorations makes it possible to obtain a predictable high-quality result. At the
same time, a smaller number of shades of the composite is used to recreate the
appearance of the teeth, which greatly simplifies the process of constructing a
restoration structure. The implementation of artistic restoration requires a
significant investment of time, and depends on the qualifications of the dentist,
scrupulous adherence to technology and the basic principles of restoration, as
well as on the technological and artistic complexity of modern restoration
systems. Training the ability of imaginary stereometric modeling and color
stratification of the future restoration, based on knowledge of the morphology
and features of the topographic structure of the crowns of the teeth, allows the
predicted result to be turned into reality.
References:
1.
Семенов
,
В
.
М
., and
Т
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Дмитраченко. «Самостоятельная работа
студентов медицинских университетов как неотъемлемый принцип
подготовки высококвалифицированного специалиста»
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Главный редактор:
проф. АТ Щастный Редакционная коллегия: проф. НЮ Коновалова, О А
Сыродоева, проф. (2017): 122.
140
2.
Бекжанова, О. Е., and Н. А. Юльбарсова. «Показатели функциональной
активности эндотелия у пациентов с хронической рецидивирующей
трещиной губ»
.
Клиническая стоматология 4 (2019): 24
-26.
3.
Иминижанова, Гулмиракхон, Тимур Мелкумян. and Анжела
Дадамова. «Современные подходы в диагностике и лечении
периимплантитов»
.
Журнал
стоматологии
и
краниофациальных
исследований
2.2 (2021): 53-57.
DIFFERENCE BETWEEN CARIES AND HYPOPLASIA
Kuzieva M. G.
students of 101
А
group Pediatric Dentistry
Scientific advisor: Ismailova M.B.
Tashkent state dental Institute, Uzbekistan
The research purpose:
А
longitudinal cohort study (from birth) regarding
the relationship between fluoride exposure, biological and environmental factors,
and oral health. Using data collected on dental caries and enamel hypoplasia in
deciduous teeth, this article reports on the relationship and differences between
enamel hypoplasia and caries.
Materials and methods:
Materials and Methods: for the medical research,
I’ve given a brief overview of caries and hypoplasia. With visual factors of their
discovery and a route to our purpose, namely, to capture some differences
between them.
Results and discussions:
hypoplasia Underdevelopment of hard tissues of
the tooth during their growth and formation Distinguish between systemic and
local hypoplasia Systemic hypoplasia is the result of various pathological
processes in the div, in which the function of ameloblasts, and often
odontoblasts, is impaired or inhibited, which leads to a violation of the
mineralization of enamel and dentin. Systemic hypoplasia of temporary teeth is
formed in the prenatal period and is associated with disorders in the div of a
pregnant woman. Systemic hypoplasia of permanent teeth is associated with
severe infectious diseases, rickets, digestive tract disorders, insufficiency of the
endocrine glands (especially parathyroid glands), metabolic disorders
Local hypoplasia is associated with a metabolic disorder in a localized area
near therudiments of permanent teeth, which occurs as a result of an
inflammatory process in theregion of the apex of the temporary tooth root or with
trauma to the developing follicle. It is more often observed on premolars, the
rudiments of which are located between the roots of temporary molars.
Hypoplasia develops as a result of the action of various factors: Endogenous
(abnormalities of embryonic cell priming) Exogenous (factors that adversely
affect the cells of the fetus or organ)
