Tooth eruption involves the migration of the teeth from a
nonfunctional position within the bone to a functional position in the
In orthodontic practice, it is inevitable that one
will encounter eruptive abnormalities such as impacted, ectopically
erupting, transposed, congenitally missing, and supernumerary teeth.
The treatment plans were developed to address these anomalies and
soft tissue reactions to the movements are considered.
Impaction is defined as the total or partial lack of eruption of a
tooth well after the normal age for eruption. An impacted tooth
may appear blocked by another tooth, bone, or soft tissue, or
displaced so that it cannot erupt .
Descending order of occurrence: maxillary and mandibular
third molars, maxillary cuspids, second premolars, maxillary
central incisors, mandibular cuspids, second molars, lateral
incisors, and first premolars.
Bishara and associates summarized Moyer's theory that impaction is caused by:
1. Primary causes:
A. Rate of root resorption of deciduous teeth.
B. Trauma of the deciduous tooth bud.
C. Disturbances in tooth eruption sequence.
D. Availability of space in the arch.
E. Rotation of tooth buds.
F. Premature root closure.
G. cleft area in persons with cleft palate.
2. Secondary causes:
A. Abnormal muscle pressure.
B. Febrile diseases.
C. Endocrine disturbances.
D. Vitamin D deficiency.
Other pathological causes for impacted teeth are cysts, tumors
(1) Delayed eruption of the permanent teeth and prolonged retention
of the deciduous teeth beyond 14 to 15 years of age
(2) absence of a normal labial bulge through intraoral palpation of
the alveolar process
(3) presence of a palatal bulge,
delayed eruption, distal tipping, or migration (splaying) of the
SEQUELAE OF IMPACTION
Shafer suggested the following sequelae:
(a) labial or lingual malpositioning of the impacted tooth,
(b) migration of the neighboring teeth and loss of arch length,
(c) internal resorption,
(d) dentigerous cyst formation,
(e) external root resorption of the impacted tooth, as well as the
(f) infection particularly with partial eruption,
(g) referred pain,
RADIOGRAPHIC DIAGNOSIS OF IMPACTED TEETH
It is two dimensional and gives no information in buccolingual plane.
To evaluate the position of the canine buccolingually, a second periapical
film should be obtained by one of the following methods.
a) Buccal object rule.
If the vertical angulation of the cone is changed by approximately 20° in two
successive periapical films, the buccal object will move in the direction
opposite the source of radiation. On the other hand, the lingual object will
move in the same direction as the source of radiation.
b) Tube-shift technique or Clark's rule.
Two periapical films are taken of the same area, with the horizontal
angulation of the cone changed when the second film is taken. If the
object in question moves in the same direction as the cone, it is lingually
positioned. If the object moves in the opposite direction, it is situated
closer to the source of radiation and is therefore buccally located.
It depicts all the posterior and anterior standing teeth in cross section
and provides buccolingual and mesiodistal information of the impacted
teeth .A palatally placed tooth will appear within this arc of small
circles. An angled tooth will show up in its elliptical oblique cross
section representing a tilted long axis.
Disadvantage:Relative height of the object cannot be made out.
OPG gives a good scan of teeth in mesiodistal and vertical direction.
Lateral cephalograms gives information regarding the vertical and
anteroposterior position of the impacted tooth especially in cases of
PA view defines the height and the buccolingual relationship.
By combining these,three dimensional view is obtained.
By viewing serial radiographic slices of the maxilla, the
relation ship of the impacted tooth to the adjacent teeth in all
three planes of space may be accurately assessed.
1.Extraction of impacted tooth and movement of adjacent tooth in its
2.Autotransplantation of impacted tooth
3.Prosthetic replacement of impacted tooth either with crown or with
4. Surgical exposure and placing a traction force to bring it into the
Sufficient space is achieved by
1.Extraction of succedaneous tooth or some other tooth or teeth
2.Molar distalisation or expansion
Once space is achieved ,surgical exposure of the tooth is performed
APICALLY REPOSITIONED FLAP
The apically positioned flap is a split-thickness pedicle reflected from
the edentulous area (lateral to the area in the case of an impaction).
The flap was sutured apically to the periosteum, leaving one-half to
two-thirds of the crown uncovered.
Negative esthetic effects, such as increased clinical crown
length, increased width of attached tissue, gingival scarring, and
intrusive relapse were evident in the teeth treated with an apically
CLOSED ERUPTION TECHIQUE
The crown of the tooth is exposed, an attachment is fixed to it, and the
flap is sutured back over the crown.
- produces the best
esthetic and periodontal results.
- High profile brackets
may lead to button holing or breakdown of
If the tooth is impacted in the middle of the alveolus or high in the
vestibule near the nasal spine, the closed-eruption technique may be
the treatment of choice. If the tooth requires more attached gingiva or
is displaced lateral to the edentulous area, an apically positioned flap
may be the best choice.(Johnston,Gaulis)
Vanarsdall and Corn suggested that keratinised tissue be placed to
cover CEJ and 2-3mm of crown as the new gingival attachment
prevents the marginal bone loss and the gingival recession.The
attached gingival is made available by apically repositioned flap, a
laterally repositioned pedicle graft , or a free gingival graft.
TUNNEL PROCEDURE ( by Cresicini)
The extraction of the deciduous tooth provided a natural osseous
tunnel, which was easily extended by drilling, to reach the cusp of
the impacted tooth. Traction through the tunnel ensured an eruption
path that closely follows the physiologic pattern.
Deep infraosseous teeth associated with persistent deciduous teeth.
Physiologic attachment levels without gingival recession and
adequate amounts of gingiva may be obtained. No gingival
augmentation procedure is required and the natural appearance of
the tissues may be preserved.
METHODS OF ATTACHMENT
In the surgical exposure of an impacted tooth, only enough bone should
be removed to allow for the placement of a bracket and that during the
procedure the CEJ should not be intentionally exposed. Different
methods of attachment to the impacted tooth have been suggested,
including lasso wires, threaded pins,orthodontic bands, simple eyelet,
crowns, wire ligatures, chain links, auxillary springs directly bonded
brackets and magnets.
MODE OF TRACTION
By using ligature wire ,elastic thread, elastomeric chains, coil springs,
NiTi archwire, Ballista spring, Killroy spring, Cantilever spring
It is necessary to develop a rigid anchor base against which to pit the
forces required to reduce impaction.Headgear ,intramaxillary elastics,
modified removable appliances and soldered palatal or lingual bars
also provides a solid anchorage base.
Fibrotomy and bonded fixed retainers are
Dentigerous cysts involved with the impacted teeth
Large dentigerous cysts in the mixed dentition are generally associated
with jaw deformity and dislocation of one or more germs of permanent
Treatment by enucleation will result in incomplete removal of the
epithelium around the neck of the tooth crown or accidental
dislodgement of the tooth during the curettage process.
Marsupialization involves opening the cyst into the oral cavity at its
most superficial point and maintaining the patency of this orifice with
the fusion of the cut linings of the cyst and the oral mucosa.
Any attempt to apply orthodontic traction to the tooth at this time will
extrude ahead of the advancing bone, thereby weakening its bony and
periodontal support..Orthodontic treatment is deferred only after
enough filling in of the bone takes place.
WHEN TO EXTRACT AN IMPACTED TOOTH
(1)If it is ankylosed and cannot be transplanted
(2)if it is undergoing external or internal root resorption,
(3) if its root is severely dilacerated,
(4) if the impaction is severe
(5) if the occlusion is acceptable, without the impacted teeth
(6) if there are pathologic changes (e.g., cystic formation,
infection), and the patient does not desire orthodontic treatment
An impacted maxillary central incisor is more conspicuous to parents
Typically, this occurs when the child is between 8 and 10 years of age
The incisor is prevented from erupting into the arch because of the presence of a
heavy band of tissue physically obstructing eruption
Treatment consists of surgically making a "window" in the tissue at the incisal edge
of the tooth. This opening is packed with a periodontal dressing for 1 to 2 weeks so
that the tissue does not heal back over the incisal edge,. The incisor tooth is then
allowed to erupt through the opening.
Second Molar Impaction
Incidence 3 in every 1000 mandibular second molars.
The usual age at presentation is between 11 and 13 years
More often than not, the mesial marginal ridge of the second molar is
"caught" below the distal contact of the first molar.
The methods of uprighting these impacted teeth include
1. surgical repositioning and orthodontic repositioning
2.extract the second molars and allowing the third molars to erupt in
Involves judicious amount of bone removed and exposure of the occlusal
surface of the tooth with deliberate wedging of the tooth between the
distal bone and the distal surface of the first molar tooth.
Loss of vitality, stunted root formation, ankylosis, and resorption of the
quick and easy procedure with minimal morbidity and good long-term
prognosis since the tooth is not removed from the socket, and in many
cases the apical vessels probably remain intact..
There has also been very limited success in extracting the second molar
and transplanting the third molar into the second molar socket probably
because of the lack of bone remaining distal to the second molars. Pulpal
calcification and degenerative changes has been noted with transplanted
It is usually necessary to effect distalizing as well as eruptive forces.
To optimize distalization, it is advantageous to remove the third molar
teeth, if present.A variety of methods include separators, superelastic
wire ,open coil springs, and segmental springs. In mild impactions, all
that may be necessary is to "dislodge" the second molar from its
trapped position under the distal bulge of the first molar. This can be
accomplished either by a simple elastic separator or by using a twisted
brass wire inserted around the contact point.
Mandibular second premolar
Crowding and space loss due to early extraction of the decidous
Abnormal premolar orientation due to abnormal angulation of tooth
Infraoccluded second decidous molars
1.Space created for the impacted tooth
2. A single rigid bar may be bonded
or banded to the first premolar and
molar tooth.The impacted tooth is
directed with labial and extrusive
Ectopic eruption can be broadly defined as the emergenceof a tooth in a
site different from its normal location, in all three planes of space.
Canine Ectopic Eruption
Incidence of approximately 0.9% to 2%.
Females are affected more often than are males.
Resorption is present in 12.5% of ectopically erupting canines.
The clinician needs to decide whether
the cuspid can be moved to its normal
position without causing or
exacerbating resorption of the adjacent
teeth. If the latter is not possible, then
canine extraction may be the best
If the canine can be moved to its normal position without passing in
close proximity to other tooth roots or is actually moved from the
vicinity of a resorbing root, then orthodontically moving the tooth is
likely to be the best option.
If the amount of root structure resorbed by the ectopically erupting
canine was significant to reduce the lifespan of the resorbed tooth,
then it may be prudent to extract the resorbed tooth and allow the
canine to erupt in the place of the extracted tooth.Prosthodontic
treatment especially porcelain veneers are used.
Selective extraction of the deciduous canines as early as 8 or 9
years of age has been suggested by Williams as an interceptive
approach to canine impaction in Class I uncrowded cases. Ericson
and Kurol suggested that removal of the deciduous canine before
the age of 11 years will normalize the position of the ectopically
erupting permanent canines in 91% of the cases if the canine crown
is distal to the midline of the lateral incisor. On the other hand, the
success rate is only 64% if the canine crown is mesial to the midline
of the lateral incisor
Ectopic Eruption of First Permanent Molar Teeth
Local disturbance characterized by eruption of these teeth under the
distal undercut of the second primary molars and failure of the first
permanent molars to erupt to the normal occlusal plane.
Seen more in children with clefts.
Higher incidence in the maxilla (2% to 6%) than in the mandible
Reversible defines a situation in which the permanent molar
can free itself from under the distal portion of the second deciduous
In the irreversible form, the permanent molar cannot free
small maxilla, posteriorly positioned maxilla relative to cranial base,
path of eruption of the maxillary first permanent molar, premature
eruption of this tooth with inadequate anterior movement of deciduous
dentition, mesiodistal widths of the maxillary first and second primary
molars, asynchronization between eruption of the maxillary first
permanent molar and tuberosity growth, and retarded eruption of the
dentition. Genetic influence is also postulated
using the width of the marginal ridge of the first
permanent molar, was adapted from Harrison and Michal as follows:
0 normal or no sign of impaction
1 minimal lock or impacted less than half the width of the distal marginal
2 moderate lock or impacted more than half the width of the distal
marginal ridge but less than the width of the distal marginal ridge
3 severe lock or impacted more than the width of the distal marginal
Ectopic eruption of the first permanent molar will result in premature
exfoliation of the second deciduous molar with a resultant loss of arch
length. The longer the impaction is continued, the more arch length will
be lost and the more difficult it will be to move the permanent molar
tooth from beneath the distal side of the deciduous molar tooth
Should an unacceptable loss of arch length have occurred, space should
first be regained and then maintained. The space can be regained by a
removable appliance with a finger spring, headgear, bands on first
permanent molar, and second or first deciduous molars with an open coil
spring in between. These appliances may be useful regardless of
whether the second deciduous molar required extraction.
If the second deciduous molar is kept in place, and its coronal mesialdistal length has been unaltered, it may serve as a space maintainer.
However, if the second deciduous molar tooth has been lost, one of a
number of devices can be used to maintain the space. These include,
among others is, the band and loop appliance, a Nance appliance, a
lingual holding arch, and a removable retainer.
Tooth transposition is the eruption of a tooth in a space normally
occupied by another tooth..
Incomplete transposition is a condition describing an interchange in the
positions of the crowns of two permanent teeth within the same quadrant
of the dental arch, while the root apices remain in their relative
Complete transposition is a similar situation in which both the crowns
and the entire root structure are transposed.
Unilateral transposition on the left side is more frequent
seen often in females and in the maxilla.
Canine and first premolar transposition (55%) more often seen than
canine and lateral incisor (45%).
Mandibular tooth transpositions are seen less frequently
Decreasing order of occurrence : canine-first premolar; canine lateral
incisor; lateral incisor-central incisor; and canine-central incisor.
Shapira and Kuftinec list the following: tooth buds interchange, retained
deciduous canines, migration of the erupting canine, heredity, bone
disease, and trauma to deciduous teeth in cases where dilaceration of the
permanent incisor roots is found adjacent to transposed teeth
Hitchin (1956), Platzer (1968), and Mader(1979) stated that it probably
occurs as a result of change in the usual preeruptive path of the
canine.Trauma to the deciduous dentition was suggested as the possible
cause for transposition in the cases with dilacerated teeth adjacent to
In the mandible the distal migration of the lateral incisor appears to be
the primary reason for the developing transposition.
Genetic factors have been offered as an explanation to the anomaly.
Bone disease,tumor or cyst, also may be responsible for the displacement
of the single canine, causing its transposition
Characteristic features of maxillary canine and first premolars:
1.retained deciduous canine
2.permanent canine often blocked out buccally and mesio-labiall
3.the transposed first premolar rotated mesio-palatally upto 90o
4.transitional crowding in the transposed area
Characteristic feature of Maxillary canine and lateral incisor:
1retained deciduous canine
2.labially blocked out and often roated canine and lateral incisor
3.small lateral incisor and missing second premolars
4.Impaction of the canine and central incisor, most often on th
CLINICAL FEATURES of Mn.I2.C transposition severe distal
tipping, displacement and rotation of the mandibular lateral incisor
as it erupts ectopically into the area normally reserved for the sameside canine and first premolar. Later, the mandibular canine erupts
transposed mesially to the ectopic lateral incisor.
When incipient transposition is detected early enough, interceptive
treatment should be initiated to remove retained deciduous teeth and
guide the ectopic tooth to its normal place in the arch.
Generally it is preferable to move teeth to their correct positions in the
dental arch. 1.alignment of teeth in their transposed positions
2. extraction of one or both transposed teeth,
3.orthodontic movement to their correct positions in the arch.
Transpositions in the maxillary arch
In incomplete transposition, uprighting and rotating the involved teeth is
most often required.
To avoid root interference or resorption during treatment, and to prevent
bony loss at the cortical plate of the labially positioned canine, the
transposed tooth (premolar or lateral incisor) should first be moved
palatally, enough to allow for a free movement of the canine to its
normal place. Subsequently, the other transposed unit can be moved
labially, back to its normal position in the arch.
Sometimes due to the difficulty of moving the roots past one another
without causing other damage, these teeth are optimally treated in their
transposed positions. They are orthodontically positioned as if they
belong in the space in which they have erupted and made aesthetically
Transpositions in mandibular arch
If the mandibular canine and lateral incisor have already erupted in
their transposed position, correction to their normal position should
usually not be attempted. www.indiandentalacademy.com
Transmigration of mandibular canines
Displacement of teeth from one quadrant across the midline to the other
side, referred to as transmigration
Less than 20% of all transmigrating mandibular canines finally erupt and
become transpositions; the rest of them remain as nonerupted, impacted
Infraocclusion of permanent teeth
Proffitt and Vig (1981) list the characteristics of primary failure of
1.posterior teeth only excluding incisors
2.some erupt and undergo submergence as in infraoccluded teeth,others
are unerupted with a large follicle
3.decidous and permanent teeth involved
4.unilateral and asymmetric
5.tendency for ankylosis
6.orthodontic treatment leads to ankylosis
Orthodontic extrusive forces will have no effect on the infraoccluded
1.Proffitt and Vig suggest that orthodontic treatment in these patients is
2.Even if attempted,procedure is surgical luxation with continous
A situation in which the cementum is directly fused to the bone,
presenting as a difficult problem for the patient and for the
Several factors, such as endocrine or
metabolic diseases, as well as local
conditions, such as periapical
infections, trauma, and previous
surgical procedures are possible
The diagnosis is based on the lack of tooth movement and by
percussion when a dull sound is obtained. When the ankylosis involves
the proximal root areas, it can be seen in periapical radiographs.
The best treatment according to Proffit is the surgical luxation of the
tooth followed by orthodontic traction.
In the case of a severely ankylosed and malpositioned tooth, one
should the following are treatment options:
1. Exodontia followed by reimplantation. External resorption usually
2. Exodontia followed by placement of an osseointegrated implant and
3. Exodontia followed by prosthetic rehabilitation, and
4. The single-tooth dento-osseous osteotomy is a feasible
procedure for upper ankylosed teeth because of the favorable
vascularity of the maxilla.Ideally, the best time to perform this
type of osteotomy would be after the facial growth has been
Often trauma is inflicted on the deciduous maxillary incisor in superior
and posterior directions will cause the crown of the unerupted permanent
tooth to rotate upwards in its crypt.The formed part of the root will rotate
with the crown. But any further root development in the post trauma
period will continue in the same direction as before, leading to a typical
dilacerated central incisor.
Other causes are the loss of deciduous incisor may lead to scaring along
the eruption path deflecting the erupting tooth. The developmental origin
has also been suggested as an alternative.
APICAL ROOT DILACERATION
If the dilacerations is situated apical to the coronal third of the root,
orthodontic alignment will result in excellent prognosis.
In most cases, the palatal surface of the crown is bonded and extrusive
force is applied. As the crown of the tooth rotates downwards, the root
apex rotates towards the labial plate of the bone. The labially directed
portion of the root is sectioned and the root canal is obliterated using a
combined conventional (coronal) and retrograde endodontic approach.
The attachment is placed on the labial surface and orthodontic force will
bring the root portion of the tooth from its more palatally displaced
location close to its normal position.
The restorative treatment is indicated later.
Long term prognosis of dilacerated tooth is poor and their extraction and
replacement is probably a part of the long term treatment strategy.
Orthodontic alignment of the dilacerated tooth will bring with it
much alveolar bone. Retention of a very short rooted endodontically
treated tooth will preserve the normal shape of the alveolar ridge.
Traumatically intruded tooth
Predominantly involves the maxillary anterior teeth.
Sequelae often includes pulp necrosis, pulp obliteration, root resorption,
ankylosis, and loss of marginal bone.
Most reported cases of permanent tooth reeruption have been those with
incomplete root formation. Traumatically intruded permanent teeth with
closed apices do not re-erupt as often. ( BRUSZT 1958, ANDREASEN
Light extrusive forces are applied after the time that the periodontal
fibres have begun to reunite and in the earlier stages of organization of
the blood clot,but before the laying down of bone i.e 10 –28 days post
A button is placed on the labial of the intruded tooth and the labial
bow of a removable plate is divided at the midline and activated
vertically downwards against the button.
Once the tooth erupts root canal therapy is initiated and
permanent restoration is placed.
Congenitally Missing Teeth
Hypodontia, is the most commonly encountered anomaly in humans.
After taking into account third molars, the most commonly missing
teeth are the second premolars and maxillary lateral incisors.
It is important to note that different races have different predilections
for congenitally missing teeth. For instance, the most commonly
missing teeth in the Asian dentition are the mandibular incisors.
Also seen in ectodermal dysplastic patients
The causes of hypodontia can at best be termed multifactorial.
Missense in MSX1 gene appears to be responsible to the agenesis
of second premolars and third molars. PAX9, a gene is associated
with tooth agenesis. A frame shift mutation is associated with
autosomal dominant oligodontia.
1. If there is crowding anticipated in the arch, then the missing tooth may
be used like an extraction space.
2 Otherwise, the space can be restored by fixed and removable partial
dentures, resin-bonded partial denture, or an osseointegrated implant
anchoring a fixed restoration. The goal of the orthodontic treatment, is to
close or redistribute the space so as to optimize the occlusal and aesthetic
effectiveness of the prosthetic restorations.
3.Autotransplantation According to Slagsvold and Bjercke,
premolar transplantations performed at any stage before complete
root formation The use of autotransplantations can be a valuable
alternative to implantation, a method complicated in children by
the involution of alveolar bone after the early loss of teeth.
MISSING MAXILLARY LATERAL INCISORS
Treatment plans are either space closure or space reopening.
Space reopening involves creating space for the missing teeth with
implants or resin bonded bridges.
Space closure is achieved by the mesial movement of the cuspids and
the bicuspids replacing the lateral incisor and the canine respectively.
•Esthetic recontouring of cuspid to a more ideal lateral incisor shape
and size, by grinding and composite resin or porcelain laminate
•Intentional whitening by vital bleaching of a yellowish cuspid
•Careful correction of the crown torque of a mesially relocated
cuspid, along with the provision of optimal torque for the mesially
moved maxillary first and second premolar..
•Individualized extrusion and intrusion during the mesial movement
of the cuspids and first bicuspids respectively to obtain an optimum
level for the marginal gingival contours of the anterior teeth.
•Nordquist has shown that an adequate group function occlusion
can be obtained with the first bicuspids substituting for the
cuspids. Increasing the width and the length of the mesially moved
first bicuspids with composite resin and porcelain laminate
veneers so as to achieve even cuspid protected guidance.
•Localized clinical crown lengthening procedures
Advantages of space closures are
(i) The treatment result is permanent.
(ii) Normal gingival topography around the mesially relocated
cuspids is created, which is crucial especially in patients with high
(iii) Cost effective since no implants or prosthetic replacements are
Disadvantages of space reopening are:
(i) Commits the patient to a life long artificial restoration in the
most visible area of the mouth where the tooth shade and
transparency along with gingival colour, contour and marginal
levels are critical.
(ii) Unaesthetic “blueing” of the marginal gingivae or even
disclosure of the implant margins is seen after several years.
(iii) The implant and the final restoration cannot usually be placed
until all the skeletal growth is completed and tooth eruption is
MISSING MANDIBULAR INCISORS
Four main theories
Heredity or familial distribution has been suggested as the primary
cause. Second, anomalies in the development of the mandibular
symphysis may affect the dental tissues forming the tooth buds of the
Third, a reduction in the dentition is regarded by some researchers as
nature's attempt to fit the shortened dental arches.
Finally, localized inflammation or infections in the jaw may have
destroyed the tooth buds, or disturbance of the endocrine system may
have caused an ectodermal dysplasia.
Congenitally missing mandibular incisors are occasionally noted in
1.the creation of space for a fixed prosthesis to replace the missing
2.the removal of maxillary premolars or a lateral incisor to balance
the deficient mandibular tooth material,
3.consolidation of the mandibular incisor spaces to facilitate
correction of the malocclusion.
Evidently the unusual occlusions of six maxillary anteriors occluding
with four or five mandibular incisors did not play a part in causing
temporomandibular joint problems.
Supernumerary teeth can be defined as those teeth in excess of the
normal dental formula.
Males are affected approximately twice as frequently as females in the
Descending order of occurrence; the mesiodenslocated between the
central incisor teeth, the maxillary third molar, the mandibular third
molar, mandibular premolar, mandibular incisor, and maxillary
Occur in conjunction with cleft palate and cleidocranial dysostosis, but
more commonly seen among otherwise normal, healthy persons
Supernumerary teeth may occur as isolated dental findings or as
part of a syndrome; cleidocranial dysostosis,Gardener`s
syndrome.Assumed to be polygenic in most instances.
supernumerary tooth is suggested to be a result of dichotomy of a
When classified by location, they are termed as mesiodens, between
the maxillary central incisors; paramolars, usually between the
second and third molars; retromolar, distal to the third molars; and
parapremolars, in the premolar region.
The shapes are divided into supplemental and rudimentary.
Supplemental teeth have a normal size and shape and are difficult to
distinguish from a "normal tooth." Rudimentary teeth are further
divided into conical, tubercular, and molariform.
SEQUELAE OF SUPERNUMERARY TOOTH
The position of the supernumerary teeth can cause crowding, malalignment or
disruption of proper eruption of the normal dentition or may lead to the development
of dentigerous or primordial cysts, root resorption of adjacent teeth or inversion of
the supernumerary into the nasal cavity. Because of these disruptions, it is usually
necessary to extract the supernumerary tooth or teeth to correctly align the dental
arches, or to allow for proper eruption.
In a small number of instances, the shape and position of the supernumerary tooth as
well as an excess of space in the dental arch will allow the supernumerary tooth to be
maintained as a part of the functioning dental unit
Early surgical excision is advised only if they are actually interfering
with the development or eruption of a permanent tooth, particularly an
Aside from this, there is much to commend leaving
them untreated until the full permanent dentition has developed and
the ideal time for orthodontic treatment is at hand. This achieves
1. A reasonable observation period is allowed to determine if other
supernumerary teeth will calcify, so that surgery can be limited to one
2. Surgical removal of supernumerary teeth may inflict damage on
The orthodontist needs to carefully evaluate developing
dentitions for eruptive anomalies during screening procedures as
these problems of eruption can be identified early and preventive
as well as interceptive or active orthodontics can be instituted
as early as possible.
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