Лекции по клинической анатомии (английский язык)

О.А. КАЛМИНА

ЛЕКЦИИ

ПО КЛИНИЧЕСКОЙ АНАТОМИИ

(АНГЛИЙСКИЙ ЯЗЫК)

Лекции

Москва

ИНФРА-М

2019

УДК [616.31+811.111](075.8) 
ББК 56.6:81.2Англ.я73

К17

Рекомендовано к изданию методической комиссией Медицинского института
Пензенского государственного университета (протокол № 05 от 11.01.2018)

Р е ц е н з е н т ы :

Н.А. 
Плотникова
—
доктор 
медицинских 
наук, 
профессор, 

заведующий кафедрой нормальной и патологической анатомии с курсом 
судебной медицины Мордовского государственного университета имени 
Н.П. Огарева;

Л.В. Музурова — доктор медицинских наук, профессор, профессор 

кафедры анатомии человека Саратовского государственного медицинского
университета имени В. И. Разумовского

Калмина О.А.

К17
Лекции по клинической анатомии (английский язык) : лекции /

О.А. Калмина. — М. : ИНФРА-М, 2019. — 91 с.

ISBN 978-5-16-107874-7 (online)

Издание содержит курс лекций по клинической морфологии зубов, читаемый 

студентам II курса специальности «Стоматология». Лекции посвящены вопросам общей 
анатомии зубов и зубочелюстной системы в целом, гистологии тканей зуба и 
поддерживающего аппарата, развитию зубов и тканей зуба в онтогенезе, возрастным 
изменениям зубов.

Предназначено для обучающихся по специальности 31.05.03 «Стоматология».

The manual contains a course of lectures on clinical morphology of teeth, which is 

readable to students of the second year of the specialty "Stomatology". Lectures are devoted to 
the general anatomy of the teeth and dental system in general, the histology of the tooth tissues 
and the supporting apparatus, the development of teeth and tooth tissues in ontogenesis, and 
age changes in the teeth.

The lectures are intended for students of specialty 31.05.03 “Stomatology” of medical 

universities learning in English.

УДК [616.31+811.111](075.8) 

ББК 56.6:81.2Англ.я73

ISBN 978-5-16-107874-7 (online)
© Калмина О.А., 2019

16+

The teeth

The teeth (dentes) are ossified papillae of the mucous membrane 

concerned with the mechanical treatment of food. Phylogenetically, the 
teeth are derived from the scales of fish which grow along the edge of the 
jaws but acquire here new functions. Since teeth wear away they are shed 
and replaced by new ones; this occurs repeatedly many times in lower vertebrates and only twice in man: (1) deciduous teeth (dentes decidui) and (2) 
permanent teeth (dentes permanentes). Sometimes the teeth are replaced 
for the third time (replacement of the teeth for the third time was encountered in a 100-year-old man).

Structure of teeth

The most important parts of the tooth, enamel and dentin, are found 

in the structure of sharks, so that one can speak of the homology of teeth of 
shark fish and man. The teeth of reptiles took a firmer position in the jaws, 
as a result of which two parts became distinguishable in the tooth: the part 
lodged in the alveoli of the jaws, the root, and the external part, the crown, 
concerned with mechanical treatment of the food. In this case, the diversity 
of food eaten by terrestrial animals and the development of their masticatory apparatus determine the development and specialization of the teeth. As 
a consequence, in distinction from the monotypical conic teeth of fish 
which serve only for the retention of food, the teeth of mammals acquired 
different shapes adapted to different types of food grasping and treating, 
namely: the tearing (the canine teeth), cutting (the incisor teeth), crushing 
(the premolars), and grinding of food (the molars).

Man has preserved all these types of teeth. Since the function of 

grasping changed from the jaws to the hands, however, the jaws became 
smaller and the teeth less in number. Placental mammals, for instance have 
44 teeth (dental formula: 3–1–4–3). The number of teeth in the New World 
monkeys is less (2–1–3–3 = 36), whereas in the Old-World monkeys it is 
still less (2–1–2–3 = 32). In man, the development of the third molar (the 
“wisdom tooth”) is sharply delayed, which reflects the tendency of regression of the teeth. A toothless man has been described as a case of anomaly.

The teeth were the first hard structures in the body of ancient verte
brates, which developed before the other parts of the skeleton. Paleontologists established that vertebrates originated in the Paleozoic era from the 
discovery of teeth, the only remnants of that time. Since the shape of teeth 
corresponds to the type of nutrition and the mode of life, the paleontologist
can recognize the fossils of animals and human beings by the teeth.

Development of the teeth

Development of the teeth in man begins approximately on the sev
enth week of embryonic life. By this time, thickening of the epithelium lining the oral cavity appears in the region of the future upper and lower jaws 
and projects as an arch-like lamina into the underlying mesenchyme. Soon 
this epithelial lamina, still penetrating deeper, divides longitudinally into 
two secondary laminae situated almost at a right angle to each other.

The anterior, or buccolabial, lamina splits eventually and transforms 

into an open epithelial fold separating the lip and the cheek from the gingiva and leading, consequently, to the formation of the vestibule of the oral 
cavity.

The posterior, dental, lamina passes almost horizontally at first, but 

as it gradually grows and penetrates deeper it becomes more vertical. Epithelial growths appear on the edge of the lamina; they take the shape of 
flask-like protrusions and are the germs of the deciduous teeth. They are 
called dental “Basks”, or the enamel organs. After the enamel organs form, 
the dental lamina continues penetrating deeper so that the enamel organs 
prove to be situated on its anterior (i.e. facing the lip or cheek) surface.

Soon after its origin, the developing enamel organ acquires the shape 

of a bowl or bell with the corresponding depression being filled by mesenchyme forming the papilla of the tooth germ.

The enamel organs gradually lose their connection with the dental 

lamina because the mesenchyme proliferates into their necks, which disintegrate to form separate nests of epithelial cells. As result the tooth germs 
are isolated absolutely.

With the further development of the isolated tooth germs, the com
ponents of the tooth develop in them in such a maimer that the epithelial 
cells give rise to the enamel, the mesenchymal tissue of the papilla gives
origin to the dentine and the pulp, while the mesenchyme initially investing 
the enamel organ as the dental sac gives rise to the cement and the root 
sheath.

Differentiation of the cells and the formation of dentine and enamel 

begin at the apex of the tooth germ and spread gradually to its base. Therefore, during the entire period of the development of the tooth germ more 
advanced stages are encountered at its apex while the nearer to its base the 
earlier are the developmental stages.

With the gradual growth of the tooth germ in length, the bony walls 

of the alveolus become higher.

The teeth are located in the alveolar processes of the maxilla and 

mandible and are jointed by means of gomphosis (Gk gomphos, belting together) (the term-is incorrect because actually the teeth are not driven in 
from the outside, but grow from the inside; this is an example of the formalism of descriptive anatomy). The tissue covering the alveolar process is 
called the gums (gingivae). The mucous membrane is closely jointed to the 
periosteum here by means of fibrous tissue; the gingival tissue is rich in 
blood vessels (and therefore bleeds relatively easily) but poor in nerves.

The grooved depression between the tooth and the free margin of the 

gum is called the gingival pocket.

Each tooth (dens) consists of: (1) a crown (corona dentis), (2) a neck 

(collum dentis), and (3) a root (radix dentis). The crown is elevated above 
the gum, the neck (the slightly narrowed part of the tooth) is embraced by 
the gum, while the root sits in the dental alveolus and terminates in an apex 
(apex radicis), on which a small opening, the apical foramen (foramen 
apicis) is seen even with the naked eye. Vessels and nerves enter the tooth 
through this opening. Inside the tooth crown is a cavity (cavum dentis), in 
which are distinguished the crown part, the widest part of the cavity, and 
the root part, the narrowed part of the cavity called the root canal (canalis 
radicis dentis). The canal opens at the apex by means of the above mentioned apical foramen. The cavity of the tooth is filled with the tooth pulp 
(pulpa dentis) rich in vessels and nerves. The tooth roots fuse tightly with 
the surface of the tooth alveoli by means of the alveolar periosteum (periodontium) supplied richly with blood vessels. The tooth, the periodontium, 
the alveolar wall, and the gingiva compose the tooth organ. The hard material of the tooth consists of: (1) dentine (dentinum), (2) enamel (enamelum), and (3) cement (cementum). The bulk of the tooth enclosing the cavity of the tooth is dentine. The crown is coated with enamel, while the root 
is covered with cement.

The teeth are so fitted into the jaws that the crowns are above the 

gums and form the dental rows, the upper (maxillary) and the lower (mandibular) rows. Each row consists of 16 teeth arranged in the form of dental 
arch.

Five surfaces are distinguished in each tooth: (1) facies vestibularis,

facing the vestibule of the mouth; in the anterior teeth it comes in contact 
with the lip mucosa and is called facies labialis, while in the posterior teeth 
it touches the mucosa of the cheeks and is called facies buccalis; (2) facies 
lingualis, s. oralis, facing the oral cavity, the tongue; (3) and (4) facies 
contactus, the surfaces coming in contact with the surfaces of the adjacent 
teeth. The contact surfaces directed towards the centre of the dental arch 

are designated facies approximalis mesialis (Gk mesos middle). This surface is medial in the anterior teeth but anterior in the posterior teeth. The 
contact surfaces directed away from the centre of the dental-row are called 
facies distalis. In the anterior teeth this is the lateral surface, and in the posterior teeth, the posterior surface; (5) the masticating surface (facies masticatoria), or the surface for occlusion with the teeth of the opposite row (facies, occlusalis).

To determine the location of a pathological process on a tooth, sto
matologists use terms corresponding to the surfaces listed above: vestibular, oral, mesial, distal, occlusal, apical (towards the apex radicis).

The following three signs are used in determining to which side,

right or left, a tooth belongs: (1) the root sign; (2) the crown angle sign, 
and (3) the crown curvature sign.

The root sign: the longitudinal root axis is inclined distally and 

forms an angle with a line passing through the middle of the crown.

The crown angle sign: the line of the masticating edge of the tooth 

forms a smaller angle where it passes to the mesial surface than where it 
passes to the distal surface.

The crown curvature sign: the vestibular surface of the crown is con
tinuous more abruptly with the mesial than with the distal surface. Consequently, the mesial segment of the vestibular surface is more convex in the 
transverse direction than the distal segment. This is explained by the fact 
that the mesial part of the crown is developed more powerfully than the 
distal part. The mesiodistal slope of the crown is thus formed.

Groups of teeth

Whether a tooth belongs to the upper or lower jaw is established 

from the shape of the crown and the shape and number of the roots. It is 
therefore necessary to know the shape and the number of roots not only of 
a definite group of teeth but also of each separate tooth of the given group.

The incisors (dentes incisivi), four on each jaw, have a crown shaped 

like a cutting chisel; they cut food to the needed size. The crown of the upper incisors is wide, twice the width of that of the lower incisors. Each 
tooth has a single root, which in the lower incisors is flattened from the 
sides. The apex of the root deviates a little laterally.

The upper (maxillary) medial (central) incisor is the largest in the 

group of incisors. The labial surface of the crown is convex in the transverse and longitudinal directions. It has three longitudinal ridges each terminating on the mastication edge of the tooth in a small projection. On 

each side of the medial ridge is a longitudinal depression. The lingual surface of the crown is concave in the longitudinal and transverse directions. 
In the region of the neck it has a small tubercle (tuberculum dentale) from 
which ridges arise and pass along the lateral and medial margins of the lingual surface to the masticating edge of the tooth. Of the three tooth signs, 
the crown curvature sign is pronounced best. The root is conical and longer 
than the crown; the ridges on its sides are weakly pronounced. It has three 
surfaces, one labial and two contacting.

The upper lateral incisor is smaller than the medial (central) incisor 

from which it is distinguished by the following features: the labial surface 
of the crown often bears a medial longitudinal groove on each side of 
which on the cutting edge in non-eroded teeth is a small nodular eminence. 
The ridges on the sides of the lingual surface are usually pronounced better 
than those on the medial incisors. A depression (foramen cecum) is often 
seen on this surface below the dental tubercle. The mesial surface is longer 
than the distal (lateral) surface and meets the cutting edge almost at a right 
angle, while the junction of the lateral surface with the cutting edge is 
rounded. The crown angle sign is well pronounced. The root is shorter than 
that of the medial incisor and is flattened in the mesiodistal direction; in 
most cases it is straight and has grooves on the sides. Its lateral surface is 
more convex that the medial.

The lower (mandibular) medial (central) and lateral incisors. The 

lower incisors are the smallest teeth in both jaws. The medial incisor is 
smaller than its distal neighbour. Both teeth possess the features characteristic of all incisors. The crown has the most typical shape of a chisel. Its 
anterior surface is slightly convex in the longitudinal direction and flattened transversely; the posterior surface is concave longitudinally and flattened transversely. The ridges are weakly pronounced or are absent in 
some cases. The root is greatly flattened.

The signs of the curvature, angle and root are absent in the medial 

incisor. The better pronounced lateral longitudinal groove on the root is 
important in distinguishing the right medial incisor from its left fellow.

The crown of the lateral incisor is wider than that of the medial tooth 

and the root is more massive. The angle and root signs are clearly pronounced, while the curvature sign is poorly pronounced.

The canines (dentes canini), two on each jaw, have a long single root 

flattened and grooved on its sides. The crown has two cutting edges which 
meet at an angle; a tubercle is seen on its lingual surface at the neck. The 
crown is so flattened that the lingual and labial surfaces converge toward 
the cutting edge. The vestibular surface is convex transversely and longitudinally. It always has a conspicuous, particularly at the cutting edge, longi

tudinal ridge dividing this surface into a smaller mesial and a larger distal 
segment. The lingual surface carries on its sides noticeable ridges converging towards the neck at the tubercle of the tooth. The cutting edge of the 
crown consists of two halves, smaller mesial and larger distal halves, 
which converge towards its apex. The distal half descends towards the corresponding contacting surface more steeply than the mesial half. All the 
tooth signs are characteristic of the canines.

The upper (maxillary) canine. The crown is massive. Its contracting 

surfaces diverge considerably towards the cutting edge. A powerful middle 
ridge passes on the lingual surface; it arises from the dental tubercle and. 
becomes considerably thicker and wider in the direction of the cutting 
edge.

The contacting surfaces are wide at the base but are relatively short. 

The root is massive and the longest of all the tooth roots. Its contacting 
surfaces are wide. In comparison with the lingual edge, the labial edge is 
blunt and wide.

The lower (mandibular) canine is smaller than its upper fellow. The 

longitudinal ridges on the labial and lingual surfaces of the crown are less 
conspicuous. The labial surface is slightly convex, the lingual surface is 
slightly concave. The contacting surfaces are almost parallel, the mesial 
does not converge towards the neck, while the distal contacting surface is 
slightly inclined towards it. The cutting edge of the crown is shorter than 
that of the upper canine but its mesial segment hardly differs from the distal in length. The root is shorter than the root of the upper canine, flatter, 
and has longitudinal grooves that are more pronounced. The root may bifurcate at the apex and a double root may form.

Teeth set in the jaw in front of the canines changed in one way: their 

crown became flat and a cutting edge formed; the teeth situated to the back 
of the canines changed in a different way; they acquired a well-developed 
crown serving for the crushing and grinding of food. The canines, meanwhile, proved to be as if in a neutral zone and maintained the initial conical 
shape and the ancient function of the tooth, i.e. the cutting and tearing of 
food. That is why they are set on the boundary between the anterior (incisors) and the posterior (premolars and molars) teeth.

The premolars (dentes premolares), four on each jaw, are set imme
diately distal to the canines. The first premolar is located mesially and the 
second distally. A characteristic feature is the presence on the masticating 
surface of the crown of two masticating or occlusal eminences, or cusps 
(tuberculum masticatoria, s. tuberculum occlusalia). That is why these 
teeth are also called bicuspid (dentes bicuspidati). One of the cusps is ves

tibular (buccal) and the other lingual. The premolars have a single root, but 
that of the upper first premolar usually bifurcates; it is flattened anteroposteriorly.

The upper (maxillary) first premolar. The buccal surface of the 

crown resembles the labial surface of the canine. Its masticating edge is 
formed of the mesial and distal segments converging on the apex of the 
buccal cusp. The mesial segment is usually longer and almost horizontal, 
as a rule; the distal segment descends more steeply. A ridge descends from 
the cusp to the buccal surface; it is bounded by longitudinal grooves. The 
crown curvature sign is reverse. The lingual surface of the crown is narrower and more convex than the buccal surface and its junction with the 
lingual cusp is more rounded. Its contacting surfaces are almost quadrangular and slightly convex. The largest convexity is in the buccal half of the 
surface at the occlusal edge and serves for contact with the adjacent teeth. 
The masticating surface is trapezoid; the buccal cusp on it is somewhat 
higher than the lingual cusp. The root is compressed mesiodistally. Each 
contacting surface has a deep longitudinal groove and is continuous 
smoothly with the lingual and at an angle with the buccal surfaces. Bifurcation of the root at the apex is encountered in more than half of cases.

The upper (maxillary) second premolar is smaller than the first pre
molar, as a rule. They differ little in shape. The buccal cusp is less developed in the second than in the first premolar. The root is usually conical 
and single. Deep grooves are seen on the contacting surfaces. The root canal may be single or bifurcate.

The upper first premolar is distinguished from the second premolar 

by several signs: in the first premolar the buccal cusp is higher than the 
lingual cusp; the root is greatly compressed and usually bifurcate; in the 
second premolar the root is conical and may bifurcate only at the apex; the 
cusps on the crown are set almost at the same level. The buccal surface of 
the first premolar is triangular and more often than the buccal surface of 
the first premolar resembles the corresponding surface of the canine.

The lower (mandibular) first premolar. The lower premolars are dis
tinguished from the upper premolars by a smaller size and a spherical 
crown whose transverse section has the contours of a circle. The buccal 
surface of the first premolar is inclined lingually; the lingual surface is narrower and shorter than the buccal; the contacting surfaces are convex and 
converge slightly towards the neck. The convexity is largest at the sites of 
contact with the adjacent teeth. The lingual cusp on the masticating surface 
of the crown is much smaller than the buccal cusp and this surface is consequently tilted lingually. The root is straight, rarely curved, and its cir

cumference is even as a consequence of which rotation may be applied in 
extraction of the tooth. The root sign is demonstrated best.

The lower (mandibular) second premolar. The crown is a little larger 

than that of the first tooth. The crown axis meets the root axis at an angle 
open in the direction of the floor of the oral cavity. The masticating surface 
is quadrangular and inclined slightly toward the floor of the mouth. The 
groove separating the buccal cusp from the lingual cusp may give rise to 
accessory grooves, in which case the tooth is tricuspid. This shape of the 
crown enables the premolars to grind the food to small fragments. The root 
has a more apparent conical shape than the root of the first lower premolari 
Besides, it is more massive and longer. All the signs determining the side 
to which the tooth belongs are clearly seen.

The molars (dentes molares). There are six molars on each jaw and 

they are smaller in the order from front to back; the first premolar is the 
largest, the third premolar is the smallest. The latter erupts late and is 
called the wisdom tooth (dens serotinus s. dens sapientia). The crown is 
cuboid and the masticating surface is more or less square (that of the upper 
molars is almost rhomboid), and has three or more cusps. This shape of the 
crown determines the function of the molars–they grind the food. The upper molars have three roots, two buccal and one lingual; the lower molars 
have only two roots, anterior and posterior. The three roots of the wisdom 
tooth may fuse to form a single conical root. This group of teeth is characterized by the crown curvature sign.

The upper (maxillary) first molar. The crown is massive, the masti
cating surface is shaped like a rhombus with the long diagonal passing 
obliquely from the anterobuccal point to the distal lingual point of the surface. The four cusps on this surface are separated by three grooves forming 
the letter H.

The mesial (buccal and lingual) cusps are larger than the distal cusps. 

The lingual surface of the crown is narrower and more convex than the 
buccal surface. The contacting surfaces are more convex at the masticating 
edge, at the site of contact of the teeth. The tooth has three roots, two buccal (a longer mesial cusp and distal cusp) and one lingual.

The upper (maxillary) second molar is smaller than the first one. 

Several variants are distinguished according to the appearance of the tooth 
and the character of the masticating surface of the crown.

The most common variant: the masticating surface bears three cusps, 

two buccal and one lingual; it is triangular with the apex facing the tongue.

The second variant: the masticating surface bears four cusps and the 

tooth resembles the first molar. In this case, the second upper molar is dis