4. • The factors that have been related to the
eruption of teeth include elongation of the root,
forces exerted by the vascular tissues around
and beneath the root, growth of the alveolar
bone, growth of dentin, growth and pull of the
periodontal membrane, hormonal influences,
presence of a viable dental follicle, pressure
from the muscular action, and resorption of the
alveolar crest.
5. • “tooth eruption is a series of metabolic events in alveolar
bone characterized by bone resorption and formation on
opposite sides of the dental follicle and the tooth does
not contribute to this process.
• Tooth eruption is influenced by pituitary growth hormone
and thyroid hormone and parathyroid hormone-related
protein is required for tooth eruption.
• Each tooth starts to move toward occlusion at
approximately the time of crown completion and the
interval from crown completion and the beginning of
eruption until the tooth is in full occlusion is
approximately 5 years for permanent teeth.
6. • The analysis of the developmental curves of individual teeth
shows a common pattern, namely, the similarity in timing
between the sexes for the early stages of development.
• مراحل في يمر الكراون تكوين:الجنسين بين متساويين مراحل ثالث اول,بينما
الرابعة المرحلة:يسبقون االناث”يصبح الفرق كأنه128يعني يوم0.35سنة”
• For the stages of root development the mean difference
between the sexes for all teeth was 0.54 year; the largest
difference was for the canine (0.90 year).
• The sexual dimorphism during the period of root
development rather than during the period of crown
development
7.
8. • Eruption of the premolar teeth is delayed in children who
lose primary molars at 4 or 5 years of age and before.
• If extraction of the primary molars occurs after the age of
5 years, there is a decrease in the delay of premolar
eruption.
• At 8, 9, and 10 years of age, premolar eruption resulting
from premature loss of primary teeth is greatly accelerated.
• Hartsfield stated that premature loss of teeth
associated with systemic disease usually results from
some change in the immune system or connective tissue.
• The most common of these conditions appears to
be hypophosphatasia and early-onset periodontitis.
9. • The mandibular canine erupted before the maxillary and
mandibular first premolars in girls. In boys the eruption
order was reversed—the maxillary and mandibular first
premolars erupted before the mandibular canine.
• the most common sequence of eruption of permanent
teeth in the mandible is first molar, central incisor, lateral
incisor, canine, first premolar, second premolar, and
second molar. The most common sequence for the
eruption of the maxillary permanent teeth is first molar,
central incisor, lateral incisor, first premolar, second
premolar, canine, and second molar
10. • the mandibular canine erupt before the first and second
premolars. This sequence aids in maintaining adequate
arch length and in preventing lingual tipping of the
incisors. Lingual tipping of the incisors not only causes a
loss of arch length but also allows the development of an
increased overbite.
• An abnormal lip musculature or an oral habit that causes
a greater force on the lower incisors than can be
compensated by the tongue allows a collapse of the
anterior segment.
For this reason use of a passive lingual arch appliance is
often indicated when the primary canines have been
lost prematurely or when the sequence of eruption is
undesirable.
11. • A deficiency in arch length can occur if the mandibular
second permanent molar develops and erupts before
the second premolar. Eruption of the second permanent
molar first encourages mesial migration or tipping of the
first permanent molar and encroachment on the space
needed for the second premolar.
• In the maxillary arch the first premolar ideally should
erupt before the second premolar, and they should be
followed by the canine. The untimely loss of primary
molars in the maxillary arch, which allows the first
permanent molar to drift and tip mesially, results in the
permanent canine’s being blocked out of the arch,
usually to the labial side.
12. • second permanent molar eruption before the premolars
and canine can cause a loss of arch length, just as in the
mandibular arch.
• The eruption of the maxillary canine is often delayed
because of an abnormal position or devious eruption
path. This delayed eruption should be considered along
with its possible effect on the alignment of the maxillary
teeth.
13. • A, The permanent central incisors are
erupting lingual to the retained primary
central incisors, which were extracted.
14. • B, The arch length is inadequate to
accommodate the permanent incisors.
However, they have moved forward into a
more favorable position as a result of the
force exerted on them by the tongue.
15. • Extraction of other primary teeth in the area is not recommended,
however, because it will only temporarily relieve the crowding and may
even contribute to the development of a more severe arch length
inadequacy.
• In either case the tongue and continued alveolar growth seem to play
an important role in influencing the permanent incisors into a more
normal position with time.
•
Extraction of the primary central incisors may result in a desirable
positioning of the permanent teeth, but given enough time this
condition probably would have been self-correcting.
16. • In most children the eruption of primary teeth is
preceded by increased salivation, and the child will want
to put the hand and fingers into the mouth. These
observations may be the only indication that the teeth
will soon erupt.
• Some young children become restless and fretful during
the time of eruption of the primary teeth. Many
conditions, including croup, diarrhea, fever, convulsions,
primary herpetic gingivostomatitis, and even death have
been incorrectly attributed to eruption.
17. • Tasanen ”دراسات“ concluded that teething does not
increase the incidence of infection, does not cause any
rise in temperature, erythrocyte sedimentation rate, or
white blood cell count, and does not cause diarrhea,
cough, sleep disturbance, or rubbing of
the ear or cheek, but that it does cause daytime
restlessness, an increase in the amount of finger sucking
or rubbing of the gum, an increase in drooling, and
possibly some loss of appetite.
18. • The surgical removal of the tissue covering the tooth to
facilitate eruption is not indicated. If the child is having
extreme difficulty, the application of a nonirritating topical
anesthetic may bring temporary relief. The parent can
apply the anesthetic to the affected tissue over the
erupting tooth three or four times a day.
• The eruption process may be hastened if the child is
allowed to chew on a piece of toast or a clean teething
object.
19. • A bluish purple, elevated area of tissue,
commonly called an eruption hematoma,
occasionally develops a few
weeks before the eruption of a primary or
permanent tooth. The blood-filled cyst is most
frequently seen in the primary second molar or
the first permanent molar regions.
20.
21. • a tiny spicule of nonviable bone overlying
the crown of an erupting permanent molar just before or
immediately after the emergence of the tips of the cusps
through the oral mucosa.
• هكذا و الدنتين و السمنتم من مركبات فوسفات كالسيوم يحوي
• seen occasionally in children
at the time of the eruption of the first permanent molar
• the hard tissue fragment is generally overlying the central fossa of
the associated tooth,embedded, and contoured within the soft
tissue. As the tooth erupts and the cusps emerge, the fragment
sequestrates.
• it may easily be removed تظهر ما بعد نستئصلها تخدير مع ممكن
22.
23.
24. • Arch length inadequacy, tooth mass
redundancy, or a variety of local factors
may influence a tooth to erupt or
try to erupt in an abnormal position.
25. • teeth that erupt during the first 30 days
• about 85% of natal or neonatal teeth
are mandibular primary incisors, and only
small percentages are supernumerary
teeth )less than 10% of neonatal teeth(. It
is common for natal and neonatal teeth to
occur in pairs.
26. • Most prematurely erupted teeth (immature
type) are hypermobile because of the
limited root development.
اشعة صورة عمل من بتأكد”خالل الفيلم بمسكو االهل
التصوير“
27. • A retained natal or neonatal tooth may cause difficulty
for a mother who wishes to breast-feed her infant. If
breastfeeding is too painful for the mother initially, the
use of a breast pump and bottling of the milk are
recommended.
However, the infant may be conditioned not to “bite”
during suckling in a relatively short time if the mother
persists with breast-feeding. It seems that the infant
senses the mother’s discomfort and learns to avoid
causing it.
28. • Small, white or grayish white lesions on the
alveolar mucosa of the newborn may on rare
occasions be incorrectly
diagnosed as natal teeth. The lesions are
usually multiple
but do not increase in size
29. • No treatment is indicated, since the lesions are spontaneously
shed a few weeks after birth.
• Cysts were classified the following three types of inclusion
cysts:
•
1. Epstein pearls are formed along the midpalatine raphe.
They are considered remnants of epithelial tissue
trapped along the raphe as the fetus grew.
•
2. Bohn nodules are formed along the buccal and lingual
aspects of the dental ridges and on the palate away
from the raphe. The nodules are considered remnants
of mucous gland tissue and are histologically different
from Epstein pearls.
•
3. Dental lamina cysts are found on the crest of the
maxillary and mandibular dental ridges. The cysts
apparently originated from remnants of the dental
lamina.
30. • The problem of ankylosed primary molars deserves
much attention by dentists. Application of the term
submerged molar to this condition is inaccurate, even
though the tooth may appear to be submerging into the
mandible or maxilla.
• The term infraocclusion, although commonly used today,
in the authors’ opinions is not preferable to ankylosis.
31. • ankylosis should be considered an interruption
in the rhythm of eruption and further observed
that a patient who has one or two ankylosed
teeth is more likely to have other teeth become
ankylosed.
• The mandibular primary molars are the teeth
most often observed to be ankylosed
32.
33. االنكلوسس حدوث طريقة
• Normal resorption of the primary molar begins on the
inner surface or the lingual surface of the roots. The
resorption process is not continuous but is interrupted
by periods of inactivity or rest. A reparative process
follows periods of resorption. In the course of this
reparative phase a solid union often develops between
the bone and the primary tooth.
34. • The diagnosis of an ankylosed tooth is not difficult to
make. Because eruption has not occurred and the
alveolar process has not developed in normal occlusion,
the opposing molars in the area seem to be out of
occlusion.
• Ankylosis can be partially confirmed by tapping the
suspected tooth and an adjacent
normal tooth with a blunt instrument and comparing the
sounds. The ankylosed tooth will have a solid sound,
whereas the normal tooth will have a cushioned sound
because it has an intact periodontal membrane that
absorbs some of the shock of the blow.
35. • presence of a permanent successor for normal
exfoliation of a primary molar is important
• no ankylosed primary molars without permanent
successors were found to exfoliate
spontaneously. However, very slow root
resorption was observed for most of the
ankylosed teeth.
36. • The incomplete eruption of a permanent molar may be
related to a small area of root ankylosis.
• The removal of soft tissue and bone covering the
occlusal aspect of the crown should be attempted first,
and the area should be packed with surgical cement to
provide a pathway for the developing permanent tooth
(Fig. 9-19).
37.
38. • Unerupted permanent teeth may become
ankylosed by inostosis of enamel.
• In the unerupted tooth, enamel is
protected by enamel epithelium. The enamel
epithelium may disintegrate as a result of
infection (or trauma),
the enamel may subsequently be resorbed, and
bone or coronal cementum may be deposited in
its place. The result is solid fi xation of the tooth
in its unerupted position
39. • delayed eruption of the teeth frequently occurs.
The first primary teeth may not appear until 2
years of age, and the dentition may not
be complete until 5 years of age.
• Earlier literature refers to DS as mongolism, but
the use of this term is inappropriate
• المريض وصف معرفة يجب:هكذا و عريض جبين كبير لسان
40. • Cichon and colleagues’ study of 10 DS patients
aged 20 to 31 years demonstrated that the
young age of onset, the severe destruction, and
the pathogenesis of disease in the periodontal
tissues were consistent with a juvenile
periodontitis disease pattern.
Dental caries susceptibility is usually low in
those with DS
41. • also been referred to as cleidocranial dysostosis,
osteodentin dysplasia, mutational dysostosis, and Marie-
Sainton syndrome. Transmission of the condition is by
either parent to a child of either sex, so that the disorder
thus follows a true Mendelian dominant pattern.
• The diagnosis is based on the finding of an absence of
clavicles, although there may be remnants of the
clavicles, as evidenced by the presence of the sternal and
acromial ends. The fontanels are large, and radiographs
of the head show open sutures, even late in the child’s
life. The sinuses, particularly the frontal sinus, are
usually small.
42. • the patients exhibited mandibular prognathism
caused by increased mandibular lengths and short
cranial bases. The maxillae tended to be short vertically
but not anteroposteriorly.
• The development of the dentition is delayed. Complete
primary dentition at 15 years of age resulting from
delayed resorption of the deciduous teeth and delayed
eruption of the permanent teeth is not uncommon
43. • One of the important distinguishing
characteristics is the presence of
supernumerary teeth.
• Treatment consisted of timed extractions
of primary and supernumerary teeth and
conservative uncovering of the
permanent teeth
44. • Hypothyroidism is another possible cause of delayed eruption.
Patients in whom the function of the thyroid gland is extremely
deficient have characteristic dental
findings.
• Congenital Hypothyroidism (Cretinism)
Hypothyroidism occurring at birth and during the period
of most rapid growth, if undetected and untreated, causes
mental deficiency and dwarfism.
Congenital hypothyroidism is the result of an absence or
underdevelopment of the thyroid gland and
insufficient levels of thyroid hormone
45. • كريتينزم تابعit is routinely diagnosed and corrected at birth because of
mandatory blood screening of newborn infants. An inadequately
treated child with congenital hypothyroidism is a small and
disproportionate person, with abnormally short arms and legs. The
head is disproportionately large, although the trunk shows less
deviation from the norm. Obesity is common.
The teeth are normal in size but are crowded in jaws that are
smaller than normal. The tongue is large and may protrude from the
mouth. The abnormal size of the tongue and its position often cause
an anterior open bite and flaring of the anterior teeth. The crowding
of the teeth, malocclusion, and mouth breathing cause a chronic
hyperplastic type of gingivitis.
The patient presented with a complete caries-free primary dentition
and partially erupted maxillary first permanent molars. All primary
teeth showed some abrasion.
46. • Juvenile Hypothyroidism (Acquired Hypothyroidism)
Juvenile hypothyroidism results from a malfunction of
the thyroid gland, usually between 6 and 12 years of
age.
Because the deficiency occurs after the period of rapid
growth, the unusual facial and body pattern characteris
tic of a person with congenital hypothyroidism is not
present. However, obesity is evident to a lesser degree.
In the untreated case of juvenile hypothyroidism, delayed
exfoliation of the primary teeth and delayed eruption of
the permanent teeth are characteristic
47. • A pronounced deceleration of the growth of the
bones and soft tissues of the body will result
from a deficiency in secretion of the growth
hormone. Pituitary dwarfism is the result
of an early hypofunction of the pituitary gland.
Again, early diagnosis is routine because of the
mandatory blood screening of newborn infants
for congenital hypothyroidism.
48. • An individual with pituitary dwarfism is well
proportioned but resembles a child of
considerably younger chronologic age
(Fig. 9-26). The dentition is essentially
normal in size.
49. • diagnosed at birth, demonstrates a few
characteristic dental findings.
• Growth of the extremities is limited
because of a lack of calcification in the
cartilage of the long bones.
50. • Stature improvements have been reported with surgical
lengthening of the limbs and also with growth
hormone therapy. The head is disproportionately
large, although the trunk is normal in size. The fingers
may be of almost equal length, and the hands are
plump. The fontanels are open at birth. The upper face
is underdeveloped, and the bridge of the nose is de
pressed
51. • The maxilla may be small, with resultant
crowding of the teeth and a tendency for open
bite. A chronic gingivitis is usually
present. However, this condition may be related
to the malocclusion and crowding of the teeth. In
the patient the development of the dentition was
slightly delayed.
52. • Delayed eruption of the teeth has been linked to
other disorders, including fi bromatosis gingivae (see
Chapter 20), Albright hereditary osteodystrophy,
chondroectodermal dysplasia (Ellis-van Creveld syn
drome), de Lange syndrome, frontometaphyseal dyspla
sia, Gardner syndrome, Goltz syndrome, Hunter
syndrome, incontinentia pigmenti syndrome (Bloch
Sulzberger syndrome), Maroteaux-Lamy mucopoly
saccharidosis, Miller-Dieker syndrome, progeria syn
drome (Hutchinson-Gilford syndrome), and familial
hypophosphatemia.
Of additional interest is the effect of bisphosphonate
therapy on children with osteogenesis imperfecta.
Bisphosphonates inhibit the ability of osteoclasts to
resorb bone. Indeed, one study demonstrated that
children with osteogenesis imperfecta that were treated
with bisphosphonates had an associated mean delay of
1.67 years in tooth eruption.79
