Hypoplasia of tooth enamel. congenital syphilis

Spots on the enamel or its darkening are not taken as seriously as we would like, and this deviation can lead to disastrous consequences if caused by a disease called enamel hypoplasia.

concept

Enamel hypoplasia is its defeat of a non-carious nature. The problem is that the formation of the matrix of the protective layer itself is disrupted, as a result of which it is damaged.

This disease can be found in people of all ages, including children. There is statistics that enamel hypoplasia occurs in 30% of people on earth.

Patients with permanent teeth are most often affected., the disease can be congenital or even acquired. The disease is inherited as a dominant trait linked to the X chromosome.

Hypoplasia affects both incisors and molars, depending on the severity of the course of the disease. It can be localized on one or two or spread to all teeth in a row.

This is due to the stage at which the disease arose.

For example, if the onset of the disease occurs before the age of 3-5 months, hypoplasia will affect the cutting edges of the tubercles of the third molars and central incisors. If the baby gets sick in the period of 8-9 months, pathological spots appear on the lateral incisors and on the cutting edges of the canines.

Provoking factors

Exists several reasons for the development of the disease:

during pregnancy there was a Rh conflict between mother and child;
if in the first 3 months of pregnancy the mother was ill with infectious diseases;
severe toxicosis during the bearing of the baby;
if the child was born prematurely;
in case of injury during childbirth;
with a lack of nutrients as a result of a lack of food (development of dystrophy);
with diseases of the gastrointestinal tract;
in violation of metabolic processes in the body, as a result of which the required amount of minerals does not enter the enamel;
with somatic diseases;
with violations of the activity of the brain, which occur during the period of development of the baby from six months to a year - just the period of teething;
with infectious diseases;
upon receiving a maxillofacial injury.

Classification

There are several classifications according to which types and forms of damage to tooth enamel are divided.

According to the picture of defeat

The state of the protective shell of the tooth is visually assessed, depending on its type of disease divided into these forms:

Erosive- deep lesions are visible on the enamel, they look like the shape of a bowl.
spotted- the outer layer is covered with spots of white or red color, which have a certain size and contour.
furrowed- this type of pathology manifests itself as linear grooves, which can be parallel to the upper edge of the tooth.

By hard tissue involvement

In this case, the division is carried out depending on the degree of spread of the pathology, hypoplasia is distinguished:

the whole tooth
only enamels.

By having a genetic predisposition

Hereditary. If family members had manifestations of this pathology, then the likelihood that a person will inherit problems with the outer protective layer of the tooth is very high.
Acquired hypoplasia occurs at the time of laying the teeth during fetal development, during childbirth, or up to six months after the baby is born.

Clinical manifestations

This pathological process can manifest itself in different forms, which need to be considered in more detail. Each of them has its own stages of development and characteristic features.

Systemic

Systemic hypoplasia is manifested by a change in the color of the enamel, its significant developmental delay or complete absence.

On the teeth, the symptoms appear as symmetrical spots that are white in color. With this type hard and soft tissues are affected.

Systemic hypoplasia is characterized by the fact that it affects the enamel of all teeth at the same time. At the same time, a person does not feel any pain or discomfort while chewing or biting.

Most often, this form of the disease can be visually determined when, during examination, the doctor sees point depressions on the teeth at different heights from the gums. With further growth of the teeth, the areas darken and become more noticeable.

Systemic hypoplasia has several options for external manifestations:

Pfluger's teeth over time, they acquire the shape of a cone due to underdeveloped tubercles on the molars, which is accompanied by an increase in the tooth from the side of the cheek and a decrease in the chewing surface.
Hutchinson's teeth have a barrel-shaped shape in the center of the dentition, their neck is thicker than the cutting surface. A characteristic of this particular type of hypoplasia is a recess in the form of a semicircle at the end of the tooth.
Fournier's teeth are similar in shape to the previous ones. This type is distinguished by the fact that there is no semicircular notch on the cutting edge.
tetracycline teeth are a consequence of taking drugs containing tetracycline. After they are taken by pregnant women or young women who have already given birth, the enamel darkens and it is no longer possible to whiten it.
The coloring of the surface can be heterogeneous, lay down in layers, darken. The incisors are most commonly affected.

Localized

This type of enamel damage appears on several teeth, due to the experienced inflammatory process or after any injury.

Photo: tooth enamel hypoplasia in a child

Visually, this form is diagnosed by white, yellow, brownish spots, dotted depressions over the entire area of the protective shell. Sometimes the disease progresses rapidly, leading to the complete destruction of the enamel. Premolars (fourth teeth) are often affected in children.

Since the protective sheath is damaged or completely absent, the tissues are actively attacked by microbes. Deep caries develops, dentin and pulp are affected.

As a result of various complications of the disease, children may develop malocclusion.

aplasia

This species is characterized by the fact that on some teeth no protective layer- enamel. Aplasia is quite rare, as it is considered a neglected state of hypoplasia.

Possible consequences

Enamel damage leads to complex diseases such as caries, inflammation of the inner layers, malocclusion in children.

It is much more difficult to treat them than hypoplasia spots, and bite pathologies have to be corrected with special orthodontic appliances in order to avoid functional disorders (chewing food, speech disorders, etc.).

In neglected conditions, children and adults experience constant pain, as microbes infect the deep shells of the tooth.

Treatment

Therapeutic measures for this disease are aimed at prevent further damage to the enamel.

It is impossible to completely eliminate the consequences of the lesion, especially at home. To do this, dental procedures must be carried out in the clinic.

Two main approaches to the treatment of enamel are used - cosmetic and orthopedic. Which one to apply, the doctor decides, depending on the degree and type of damage.

Cosmetic

The principles of cosmetic treatment are to visually hide the unaesthetic appearance of the enamel and stop the destructive effect of the disease.

To do this, doctors use several methods:

With a slight lesion, when only a few age spots are present, prescribe remineralization and other preventive measures.
For the procedure, pastes or gels are used, allowing the outer layer of the tooth to make up for the lack of minerals.
Grinding used in the case when the pigmentation of the protective layer is pronounced. This protects against the progression of the disease and reduces the intensity of its manifestation.

Orthopedic

Orthopedic therapy is used already in more advanced conditions.

For this two methods are used:

If hypoplasia is started, develops rapidly and erosive depressions have already appeared on the enamel, resort to their filling composite materials.
As an alternative, lumineers or veneers are used - special orthodontic overlays that hide their shortcomings.
If hypoplasia has affected extensive areas of enamel and it is impossible to save the tooth, prescribe prosthetics.

How is the process of treatment of enamel hypoplasia, look at the video:

Prevention measures

If there is a hereditary tendency to develop this disease, do not take it lightly. It is important to visit the dentist periodically to prevent the destruction of the protective layer.

To prevent the occurrence and development of enamel hypoplasia, it is important not to neglect preventive measures. They can be both systemic, to strengthen the body as a whole, and related directly to the oral cavity.

General

It is important even during the formation of the baby's organs during pregnancy to think about the health of his teeth. To do this, the mother should take care of a balanced diet so that the necessary trace elements enter the baby in utero.

It is necessary to prevent the possibility of domestic and traumatic injuries of the child's teeth. Timely treat infectious diseases and prevent complications after them.

It is important for both a child and an adult to increase immunity, which naturally prevents the development of this devastating disease.

Local

Local methods for the prevention of hypoplasia include the timely treatment of enamel diseases, caries, and inflammation of the gums. Sometimes preventive remineralization of teeth is prescribed.

In addition, you should carefully select care products for milk teeth, especially the first ones. On the Komarovsky website, it is recommended not to use pastes, even with a minimum fluoride content, for children under 3 years old.

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Hypoplasia of tooth enamel is a congenital disorder of the tooth structure, caused by severe metabolic disorders in the fetus and mother, as well as underdevelopment of hard tissues. In adults, the pathology may be acquired. The disease leads to early loss of their teeth, irreversible changes in bite.

According to statistics from European sources, up to 72% of cases are secondary and are caused by a number of negative processes, autoimmune and systemic pathologies of internal organs and systems.

What is tooth enamel hypoplasia

Enamel hypoplasia refers to non-carious dental diseases with a high tendency to irreversible tooth decay.

Hypoplasia provokes two types of morphological and structural changes:

Qualitative: pigmentation, turbidity, low content or complete absence of minerals, mottling.
Quantitative: the appearance of grooves, dimples, severe thinning of the tooth.

The main danger of pathology is the complete destruction of the tooth and its loss as a result of a widespread irreversible process.

Video: What is enamel hypoplasia?

Note!

Hypoplasia manifests itself to varying degrees in children of early and school age, especially during the period of change of milk teeth to permanent ones.

The difference between the children's form is the rapid defeat of two or more teeth. The primary appearance of signs of enamel hypoplasia is also found in absolutely healthy children.

All causes of tooth enamel hypoplasia in children and adults - who is at risk?

The outer protective layer of the tooth is designed to protect it from the negative effects of external factors.

Normally, the enamel layer is dense, thick, durable.

With congenital or secondary hypoplasia, the first symptoms are noticeable on the first teeth of the baby. Acquired forms are accompanied by gradual destruction of the enamel layer.

The result of the destruction of enamel is the thinning of the tooth of varying severity.

Causes of tooth enamel hypoplasia in children

Thinning or complete absence of enamel in milk teeth develops for a number of the following reasons:

Negative factors of the prenatal period (exposure to toxins, medications).
Difficult neonatal period (deep prematurity, birth trauma, asphyxia, hypoxic syndrome).
Maternal diseases of any nature (hormonal and metabolic disorders, alcoholism, toxoplasmosis, convulsions and epilepsy, rubella, measles).
Deficiency of vitamins, nutrients.
Irradiation, chemotherapy.

Often, hypoplastic changes are combined with pathologies in the development of internal organs. So, with nephrotic syndrome in a child, enamel underdevelopment occurs due to persistent electrolyte disturbances, which is secondary.

Causes of enamel hypoplasia on permanent teeth

The destruction of tooth enamel in adults and children over 12-14 years of age is associated with the following provoking factors:

Neurological disorders, diseases of the central nervous system, impaired calcium-phosphorus metabolism.
Endocrine pathologies: hypothyroidism, hyperparathyroidism, impaired mineral metabolism, persistent electrolyte disturbances.
Diseases of the digestive tract, toxic dyspepsia.
Severe hypovitaminosis, in particular lack of vitamin D, E, C.
Burdened dental and allergic anamnesis.

On a note!

Poor nutrition, unfavorable environmental conditions, harmful working and living conditions - all this can provoke the development of diseases with dental complications. In the risk group of persons with a lack of vitamin D, with burdened dental heredity.

Symptoms of tooth enamel hypoplasia are the first signs when you need to see a dentist!

The underdevelopment of tooth enamel is accompanied by two main symptoms: a change in the enamel pigment and thinning of the tooth.

Symptoms of the disease develop in accordance with the stage of the disease:

I stage - initial. The color of the tooth gradually changes, the enamel becomes cloudy. With hypomineralization, white-yellow spots appear on the frontal surface of the teeth. First, the canines and incisors are affected. The early stage is accompanied only by external changes. The main diagnostic feature is that the chalky spot has a glossy surface and does not change color when exposed to dyes.
II stage - aggravated. The disease progresses markedly. Patients note not only external manifestations, but also some tangible symptoms: pain, tooth sensitivity, a strong reaction to irritability, dark pigmentation, symmetry of points, depressions and grooves.

If the first changes differ in superficial changes, then the later ones cover the entire depth of the enamel layer and become irreversible.

Attention!

You should consult a dentist already at the stage of formation of a chalky spot. Then there is still a chance to save the tooth.

Types and forms of dental hypoplasia, aplasia

The classification of hypoplasia does not differ in numerous criteria. For clinicians, the type and form of the development of the disease is sufficient for the final diagnosis.

By type of prevalence

The pathological process can be widespread (systemic) and focal (local). Systemic enamel hypoplasia is manifested by the defeat of two or more teeth with a characteristic change in their color.

The disease has a high tendency to rapidly spread to all teeth.

Focal pathological process covers 1-2 teeth. The cause of local hypoplasia is often trauma, inflammatory processes (for example, hematogenous osteomyelitis).

The quality of enamel on permanent teeth depends on the condition of the protective layer of milk teeth. Mechanical damage to the enamel, apical periodontitis, periodontal disease can lead to the development of local hypoplasia.

By shape

Various forms of hypoplasia are characteristic of the aggravated course of the pathology.

There are several main structural changes:

Spotted - the structure of the tooth enamel is normal, white-yellow spots are visible on the surface.
Erosive - crater-shaped spots are formed on the surface of the enamel, different in depth and diameter (at the depth of the yellow tissue).
Wavy - multiple grooves merge with each other, form waves, completely changing the structure of the enamel surface.
Furrowed - grooves are formed on the surface, parallel to the cutting edge, with different depths and shades.
Combined - enamel damage has several different signs and defects.

The patchy form is a popular type of pathology that occurs in 53% of all clinical cases of hypoplasia.

aplasia

Of particular clinical importance is another form - aplasia. Pathology is usually distinguished as a separate disease.

Aplasia is the complete absence of enamel. It is extremely rare, it is characterized by a special severity of the course. The symptomatic complex is always intense, bright: high tooth sensitivity, abnormal structure, rapid and severe carious lesions.

Note!

The prognosis for aplasia in relation to the preservation of one's own teeth is doubtful.

In childhood, the teeth are covered with a protective coating, demineralized. Already by the age of 18-20 exists.

Why is the partial or complete absence of enamel on the teeth dangerous?

The danger of enamel hypoplasia and aplasia lies in the absence of a full-fledged protective layer. Infections quickly penetrate deep into the tooth, destroying the dentin and pulp.

Firstly, symptomatic manifestations worsen the quality of life of patients, cause.
Secondly, the dental cement is quickly loosened, and the mobility of the root leads to the loss of the tooth.

In children, it is not uncommon, which threatens with even greater complications (development of diseases of the digestive tract, impaired speech, salivation).

As an X-linked dominant trait.

1) What is sex-linked heritage? Explain X-linked nasl.

sex-linked inheritance - the inheritance of gene located in sex chromosomes.

X-linked inheritance:

A) Dominant - the trait is more common in women, because it has two X chromosomes. Women with dominoes. by sign they pass it on equally to daughters and sons, and men only to daughters. Sons never nasl. from fathers X-clutch. sign.

B) Recessive - a sign manifested. In homozygous males who inherit the trait from mothers with dominoes. The phenotype that are carriers of the recession. allele.

2) Other types of inheritance:

A) Autosomal dominant - a sign of equally meetings. in men and women and can be traced in every generation.

B) Autosomal recessive nasl. - the trait can be traced only in an individual homozygous for this allele.

C) Y-linked nasl. - the trait appears only in males in each generation.

3) 100% because Boys acquire the X chromosome only from their mother.

4) No, because Women inherit one X chromosome from their mother and another from their father. It follows that the X-chromosome of the father containing the dominant gene will pass to the girl, the gene will appear with a probability of 100%

5) Diseases linked to the X chromosome:

Follicular keratosis is a skin disease characterized by loss of eyelashes, eyebrows, and hair. It is more severe in homozygous men than in heterozygous women.

Hemophilia is an inability to clot the blood. Passed down from mother to son.
Ticket number 46

Situational task No. 1

A son was born to healthy parents ... ..

Answer: 1) Duchenne myodystrophy occurs with a frequency of 3:10,000 live births of boys. Genetically, it is an X-linked recessive lethal disorder. With the clinical picture of Duchenne myodystrophy in girls, monosomy on the X chromosome (Turner syndrome) should be excluded. The possibility of developing Duchenne muscular dystrophy in girls with a 46,XX karyotype is not excluded due to the inactivation of the X chromosome with a normal allele in all (or almost all) cells in the early stages of development (16-32-cell blastocyst).

2) Combinative variability. MECHANISMS OF APPEARANCE: 1- diversity of gametes: a) independent inheritance b) linked inheritance; 2- random meeting of gametes; 3- random selection of parent pairs.

3) Variability happens: genotypic (a change in the genotype is the cause of a change in a trait) is mutational and combinative; phenotypic (the influence of the environment, but the genotype does not change).

Situational task No. 2

In developed countries, there is an increase in...

The aging process manifests itself at the molecular, subcellular and cellular levels. The intensity of DNA molecular repair decreases, the level of transcription and translation decreases. The number of mitochondria decreases in cells. A typical feature of the aging of nerve cells is the increasing accumulation of the pigment lipofuscin in the cytoplasm with age. Destruction of microfibrils was found in cardiomyocytes, free radicals accumulate in many cells. Currently, the existence of genetic control of aging processes has been proven. Despite all these mechanisms of aging, it is possible to resist the onset of old age. A person has special adaptive mechanisms for slowing down old age, for example, a high level of social and labor activity, maintaining mental and physical performance until old age. The intake of low-calorie foods, systematic physical exercises, etc. also prolong life. To date, the species life expectancy of a person has not been determined. Reliable maximum life spans rarely exceed 120 years. Apparently, the achievement of medical and other sciences will help mankind to increase life expectancy.
Situational task No. 3

In the practice of a dentist, there are ....

Answer:

Answer : These are atavistic malformations of the dental system associated with the underdevelopment of organs at that stage of morphogenesis, when they recapitulated (repeated) the ancestral state, i.e. these anomalies were once the norm for more or less distant ancestors.

Answer: biogenetic law

Answer:

Sealing of the dentition

Answer:

Reducing the size of teeth

Diphyodontism

Heterodont dental system

The taiga tick goes through 4 morphological phases in ontogenesis: an egg and three active phases separated by molts (larva, nymph and adult tick). Each stage of development has its own specifics of the external structure. In adult ticks, sexual demorphism is pronounced.

The taiga tick (lxodes persulcatus) is an arachnid animal, not an insect (as it is called in the mass media). The flat and dense body of the tick has 4 pairs of legs. There are no eyes. The head is armed with oral organs, forming the so-called proboscis with large teeth directed backwards, as well as organs of touch, smell and taste. Inside the proboscis are claw-shaped jaws, with which the tick cuts through the skin of a warm-blooded animal. He feeds on blood. A tick waiting for its prey climbs a blade of grass or a bush, to a height of no more than half a meter, and patiently waits for the opportunity to cling to the body of a mammal, bird or person. Crawling over the body, the tick chooses a place to feed for a rather long time. Its saliva, subsequently secreted into the wound of a warm-blooded animal, contains a wide variety of biologically active substances. Some of them anesthetize the wound, others destroy the walls of blood vessels and surrounding tissues, and others suppress the immune reactions of the hosts aimed at rejecting the tick.

Having fed, the female goes to the forest floor and, having digested the blood, proceeds to oviposition, laying 1.5 - 2.5 thousand eggs, from which, after a few weeks, larvae appear, the size of a poppy seed. The larvae attack small rodents in the soil. Then they go into the forest floor. There they molt and turn into the next phase of development - nymphs. After wintering, the nymphs similarly go out to "hunt", watching for squirrels, chipmunks, hares, and hedgehogs. A nymph that has fed in a year turns into either a female or a male. Ticks live 4-5 years. In nature, ticks are designed to contain emerging foci of infection, and thereby prevent pandemics among warm-blooded animals: mammals and birds. Thanks to the taiga tick and blood-sucking insects, all wild animals and people associated with the forest from childhood are immune to viral diseases. The number of ticks in the forest area largely depends on the number of their original hosts - small rodents, birds and nests with chicks. Ticks are introduced into the anthropogenic landscape by domestic and wild mammals and birds.

The taiga tick in its tiny body carries more than a dozen vaccines against infections, including encephalitis, lyme borreliosis, human granulocytic ehrlichiosis, human monocytic ehrlichiosis and others. This is a whole mobile natural laboratory on eight legs, which few of us have appreciated so far. The thing is that all "dangerous" infections from a human point of view, including encephalitis, circulated in our environment long before the appearance of both the taiga tick itself and humans. The most important role in maintaining natural foci of infection today belongs to small forest animals - voles, mice, shrews, squirrels and chipmunks. The animals themselves are also susceptible to infection, and viruses multiply well in their body, but the disease proceeds without visible harmful consequences.

Only thanks to the taiga tick, as an intermediary between a sick animal and a healthy person, we get a real 100% natural vaccine against possible infectious complications in the future. And almost free of charge, having paid off with a tick only a microdose of his blood. Doctors give us similar vaccinations in childhood, for example, against smallpox. But at an older age, many vaccinations for humans are ineffective or contraindicated. Therefore, the sooner a person encounters ticks, the better for the immune system of our body. Only those people who have been cut off from the wild since childhood (townspeople), with poor health, as well as people who have a negative attitude towards other species (vision-haters) or who panic because of fear of ticks inspired by the press and television, should beware of ticks. This is beneficial only to those who earn money on artificial and far from safe vaccinations, as well as useless tick bite insurance. A very expensive immunoglobulin does not provide one hundred percent protection against the disease and is not so harmless to our health and immunity.

Mite development cycle:

1 - first host, 2 - well-fed female, 3 - eggs, 4 - hungry larvae, 5 - second host, 6 - well-fed larvae, 7 - hungry nymph, 8 - third owner, 9 - well-fed nymphs, 10 - female and male tick.

1. Healthy parents had a son with severe hereditary diseases Duchenne myodystrophy (recessive X-linked trait)

1. The reason for the birth of a sick child?

Duchenne muscular dystrophy occurs with a frequency of 3:10,000 live births of boys. Genetically, it is an X-linked recessive lethal disorder. With the clinical picture of Duchenne myodystrophy in girls, monosomy on the X chromosome (45-XO Turner syndrome) should be excluded. The possibility of developing Duchenne muscular dystrophy in girls with a 46,XX karyotype is not excluded due to the inactivation of the X chromosome with a normal allele in all (or almost all) cells in the early stages of development (16-32-cell blastocyst).

2. What kind of variability appeared in this case? Possible fur-we are the occurrence of such variability?

Combination variability. MECHANISMS OF ORIGIN: 1- gamete diversity) independent inheritance b) linked inheritance; 2- random meeting of gametes; 3- random selection of parent pairs

3. Types of variability?

Change happens: genotypic(a change in the genotype is the cause of a change in a trait) it can be mutational (according to a change in the genetic material, they are GENE, CHROMOSOME, GENOMIC.) and combinative;

phenotypic(the influence of the environment, but the genotype does not change).

4. Determine the probability of having a healthy child with these parents

The probability of having a phenotypically healthy child is 75%

(50% of girls will be carriers, 50% of boys will be sick)

5. Is there a genetic method that allows diagnosing this disease?

Genealogical method - compilation and analysis of pedigrees
2. In developed countries, there is an increase in average life expectancy. Anthropologists attribute this to a decrease in infant mortality, improvement in living conditions, etc. The processes of aging are being actively studied and possibly. influence on them, which would extend the period of active life.

Answer: The main theories of aging:

error hypothesis - according to this theory, errors can occur during DNA synthesis that will affect the structure of proteins, enzymes. With age, the number of errors and breakdowns increases.
free radical hypothesis - according to it, the accumulation of free radicals in the process of metabolism increases, they can combine with DNA, RNA and cause changes in their structure. Therefore, one of the ways to combat aging is the use of antioxidants (vitamins C, E, carotene, selenium)
theory of V.M. Dilman - the cause of aging is a violation of the hormonal regulation of the body.
I.P. theory Pavlova - overstrain of the nervous system - stress accelerates the aging process.

Individual rates of aging, as well as development, can vary significantly among people of the same chronological age. Smoking, drug addiction, alcoholism accelerate the rate of aging and, as a result, shorten life expectancy. The nature of nutrition has a significant impact on the state of human health. So the use of fatty meat food leads to the development of atherosclerosis, strokes, heart attacks. Obesity is an increased risk factor for death.

1) How can these defects be explained in terms of phylogenesis?:

These are atavistic malformations of the dental system associated with the underdevelopment of organs at that stage of morphogenesis, when they recapitulated (repeated) the ancestral state, i.e. these anomalies were once the norm for more or less distant ancestors.

2) What law reflects the connection between the individual and historical development of the organism?

biogenetic law(E. Haeckel, F Muller) - ontogeny is a short and quick repetition of the phylogeny of a given species.

The law of germinal similarity - in the early stages of development, embryos of animals of the same type are similar.

3) The main evolutionary transformations of the dentoalveolar system of vertebrates?

Reducing the number of jaws

Transition from homodont (all teeth of the same shape) system to heterodont

Differentiation of teeth by function (incisors, canines, chewing) and, as a result, differentiation. chewing surfaces.

The transition from polyphyodontism (multiple change of teeth) to diphyodontism (change of teeth 2 times in a lifetime)

General decrease in the number of teeth

Sealing of the dentition

Changes in x-py attachment (Acrodont Pleurodont Tectodont)

The appearance of multicellular salivary glands, etc.

4) Homologues of what structures of the lower vertebrates yavl. teeth?

Teeth yavl. placoid scale homologues.

5) Evol. transformation of the dentoalveolar system. human?

Reducing the number of teeth.

Reducing the size of teeth

Diphyodontism

Heterodont dentistry. syst.

An increase in the number of tubercles on the zhev. surfaces (tetratubercular obtuse tuberculate)

Attachment Tectodont (in cells of alveolar processes)

Rounded dental arch, etc.
4. TAIGA TICKETS

1. The taiga tick belongs to the Ixodes family and is a carrier of a severe transmissible natural focal disease that affects the human nervous system - tick-borne spring-summer encephalitis.

2. ixodid ticks quite large - from a few millimeters to 2 cm, depending on the degree of saturation. At the anterior end of the body, the oral apparatus protrudes strongly forward. The main component of the proboscis is the hypostome - a long flattened outgrowth bearing sharp teeth directed backwards. Chelicerae look like stabbing stylets, serrated on the lateral sides. With their help, an incised wound is formed in the host's skin, and a hypostome is introduced into it. The midgut has numerous outgrowths that fill with blood during feeding. Here the blood can be stored for up to several years. The entire dorsal side of the male is covered with an inextensible chitinous shield; in the female, such a shield occupies no more than half of the body surface; therefore, the female's integuments are much more extensible and she can drink much more blood. After feeding, females lay from 1,500 to 20,000 eggs in forest litter, soil cracks, in rodent burrows.

3. Development occurs with incomplete metamorphosis (egg - larva - nymph - adult).

-Larvae have three pairs of walking legs. They feed on the blood of lizards and small rodents.

The next stage of the life cycle - nymph. She is

The most common problem with teeth is caries. Therefore, most people assume that caries is the only reason why teeth can decay. But in fact, there are also diseases that do not have a carious nature, in which damage occurs not under the influence of environmental factors, but because of the peculiarities of their structure.

Such problems include hypoplasia of tooth enamel. This disease carries a serious danger, and tooth damage caused by this disease cannot be treated or completely restored. However, early identification of the problem can significantly change the situation. Accordingly, it is very important to detect the disease at its early stage, as well as to establish the reasons for which it arose. In this, dentists are helped by symptoms, as well as various kinds of diagnostics.

The concept of hypoplasia

The layer of enamel that covers the tooth of a healthy person has a fairly strong structure, because its main purpose is to protect the internal structures of the tooth from the negative effects of the external environment. However, situations are possible in which the problem occurs due to internal problems in the body. For example, tooth enamel hypoplasia is a disease that can affect everyone without exception.

The most common variant of the disease is tooth enamel hypoplasia. When this disease occurs, the damage to the tooth is of a non-carious nature. The causes of hypoplasia are considered to be deviations that arose in the process of formation and formation of enamel. As a result of such a pathology, the enamel layer becomes thinner, and the pathology can have a different form of severity.

Types of hypoplasia disease

Dentists note that enamel damage in mild hypoplasia can be minimal, but the disease is also severe. In this case, the tooth does not have a protective layer at all. This form is called aplasia.

The development of this disease can begin at any age. Despite the fact that enamel hypoplasia is most common in children who still have milk teeth, there is no guarantee that the same symptoms will not occur in an adult.

If we adhere to the main classification, then the disease can be conditionally divided into two types - systemic hypoplasia and local hypoplasia. When a systemic form of the disease occurs, the greatest threat appears, since in this case the entire enamel layer of the tooth is affected. The systemic form of hypoplasia in a serious condition implies not so much a thinning of the enamel layer, but its serious underdevelopment, which manifests itself in the form of the formation of waves, furrows and dots. Hypoplasia in the local form often affects those who have undergone any damage at the formation stage.

Hypoplasia of tooth enamel is a rather serious problem, since it results in a general weakness of the tooth and its protective layer, which, in turn, is a favorable environment for the occurrence of other pathologies and diseases.

Causes

Currently, doctors adhere to two main theories regarding the nature of the occurrence of hypoplasia. The first group of specialists believes that the beginning of the process that destroys enamel can be triggered by disturbances in mineralization. Another group of specialists is of the opinion that such a cause is not isolated, and the slow function of epithelial cells in the tooth germ also affects the development of hypoplasia. However, it should be noted that, along with physiological causes, other factors are of great importance, which create a favorable environment and conditions for the further development of enamel hypoplasia of permanent teeth.

Diseases of milk teeth

Due to the fact that the formation of milk teeth occurs at the stage of intrauterine development of an infant, their general condition to a large extent depends on how the pregnancy proceeded, as well as on the state of health of the mother of the child.

The following factors can influence the development of enamel hypoplasia of milk teeth in an infant during its development in the womb and during childbirth:

diseases of the digestive system in the mother;
infectious diseases that were carried by the mother during pregnancy;
deviations in the position of the fetus;
congenital diseases of the cardiovascular system;
the influence of factors such as chemicals or hazardous temperatures;
feeding a child artificially;
prematurity. Experts are of the opinion that the latter reason has become relevant not so long ago and has led to an increase in the number of children suffering from hypoplasia. The situation is such that modern technologies make it possible to nurse even too premature babies, but in such children the processes of tissue and organ development have not yet been completed properly. In this regard, premature babies subsequently suffer from hypoplasia of the enamel of milk teeth, since there was a violation of the process of its formation, or it was completely interrupted;
oligohydramnios;
severe toxicosis;
traumatic injuries. These include also injuries received during childbirth;
bad habits during pregnancy.

All these factors cause enamel hypoplasia of milk teeth in a child at an early age.

Pathology of molars

Such a pathology can begin to develop at an early age, in the first years of a child's life. The formation and development of the embryos of the molars begins to occur at about six months of age. Therefore, it is quite logical to assume that a violation of the state of health at this age can provoke the process of impaired development of tooth enamel. In this regard, hypoplasia of the molars can often be detected in those people who in childhood suffered such diseases as:

severe forms of infectious diseases;
rickets;
kidney disease, as well as disorders in the endocrine system;
syphilis;
serious disorders in the digestive system;
anemia due to iron deficiency;
brain dysfunction.

Hypoplasia of the enamel of the teeth will develop and appear on the molars, depending on the age at which the child suffered a particular disease. For example, if the disease was transferred at the initial stages of life, then damage to the tooth enamel can be observed along the edges of the central incisors and the first large permanent teeth. The disease in the ninth month of life can provoke enamel damage on the incisors of the second and third order on both sides, as well as on the central incisors and large chewers in the area of \u200b\u200btheir crown.

Symptoms of hypoplasia

Diagnosis of this disease is not a difficult procedure for a competent specialist, because specific symptoms are inherent in it. But patients should still independently monitor the condition of the enamel of their teeth. Only this will allow timely detection of the problem at the stage of its early development.

Systemic form of hypoplasia

As we have already noted, the systemic form of the disease can manifest itself in various degrees of severity. So, with the appearance of a mild form, a partial change in the color of the tooth enamel is observed - yellowish areas are formed on its surface, which have clearly defined boundaries. Such defects can be seen in the photo with tooth enamel hypoplasia. The specificity of this form lies in the fact that lesions in the form of spots have exactly the same size and are located symmetrically - on the same teeth on both sides of the jaw. Most often, this form of the disease affects the front side of the teeth, therefore, if you pay due attention to the condition of your teeth, then the development of the disease at an early stage is absolutely not difficult to notice. With this form of hypoplasia, pain is not felt, and the thickness of the tooth enamel on the affected and healthy areas of the tooth is the same.

With the second degree of complexity, underdevelopment of tooth enamel occurs, which can be characterized by the appearance of changes of various types. The wavy pattern can be visually identified even in the absence of additional devices. If you dry the tooth, then small rollers will be visible on its entire surface. Another manifestation is the grooves - they, as a rule, have a single location and are located across the tooth. Along with wave-like manifestations, the grooves are located alternately with healthy areas of tooth enamel. The third type of manifestations is the most common - point. In this case, recesses are located along the entire surface of the tooth, which eventually change their color to a darker one. Therefore, it is necessary to detect and begin treatment of tooth enamel hypoplasia in children in time.

aplasia

The most dangerous stage of hypoplasia is aplasia, that is, a form in which tooth enamel is completely absent. Such a manifestation can be localized in a certain area of the tooth or may affect the entire tooth. With this form, there are significant pain sensations that occur as a reaction to environmental stimuli. A specific characteristic is that the painful sensation disappears immediately after the external impact on the tooth has been stopped.

local form

The main sign of the local form of enamel hypoplasia of permanent teeth in children and adults is the appearance of spots on the surface of the enamel coating, which may have a different color. Shades of such spots can range from pale yellow to dark brown. Such damage to tooth enamel is manifested by the formation of depressions of a punctate nature, which are everywhere located over the entire surface. It is worth noting that this form can only appear on the molars.

Diagnosis of hypoplasia

Enamel hypoplasia is inherited as an X-linked dominant trait. As a rule, the diagnosis of hypoplasia does not cause difficulties for dentists due to the fact that the disease has visual symptoms that can be easily noticed. The main task of the dentist is to differentiate hypoplasia from a carious lesion. In order to conduct such an examination, doctors use three main methods:

visual assessment of the enamel surface. With carious manifestations, the tooth enamel has a rough surface, and with hypoplasia, it remains smooth;
assessment of the number of spots (multiple manifestations are characteristic of hypoplasia);
staining of the affected areas of enamel with a solution of methylene blue. Spots characteristic of hypoplasia are not stained with this solution, unlike carious lesions.

Treatment of enamel hypoplasia of permanent teeth

The method of treating the disease depends on the clinical manifestations, that is, on the form and severity of the pathology, as well as on the nature of the changes.

If hypoplasia is manifested by the appearance of light spots on the enamel in small quantities, which are located in areas of the teeth that are not too visible, treatment of such a manifestation is not necessary.

In the event that the spots are located on the front surface of the incisors and are noticeable, the defect can be eliminated. Unfortunately, it is not possible to restore the affected enamel, so the doctor can use various filling materials, as well as veneers or crowns.

What to do if hypoplasia in the form of furrows and stripes?

If the disease manifested itself in the form of depressions, furrows or stripes, then filling the tooth according to the classical scenario may be effective.

If the teeth restored in this way are treated with care, they will be functional and aesthetic for a sufficiently long period.

Veneers are plates that the dentist attaches to the outer surface of the tooth. This type of crown has an impeccable appearance, but the inside of the teeth still does not look very attractive. But due to its invisibility, veneers can be an excellent solution in the treatment of hypoplasia.

If the tooth has a sufficiently altered shape, formed as a result of pathology, then dentists tend to use orthopedic crowns. Installing such a crown is quite a difficult job. Therefore, if there is an alternative possibility to restore the aesthetic appearance of the teeth, then the installation of an orthopedic crown should be postponed.

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