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EUROPEAN JOURNAL OF PAEDIATRIC DENTISTRY • 1/2006
29
Radiographic appearance of
apical closure in apexification:
follow-up after 7-13 years
I. BALLESIO*, E. MARCHETTI, S. MUMMOLO, G. MARZO
ABSTRACT.AimThis was the radiographic evaluation of 15 maxillary incisors apexification treatment carried out
on 7-9 years old patients with periapical pathology due to pulpal necrosis after dental trauma.
Materials and Methods The treatment consisted of two phases. The aim of first phase was the formation of a
calcified apical barrier through calcium hydroxide medications repeated twice with a three months interval. The
aim of the second phase was the obturation of the root canal system once achieved a radiographic evidence of
the formation of an apical barrier. The treated teeth were radiographed at six months and then periodically once
a year for a period of 7 and 13 years. Results The radiographic analysis allowed to underline three different kinds
of apical formation: a physiological development of the apical portion with a final root length equal to the
controlateral tooth; the formation of a cap tissue and an apical development with the final root length slightly
shorter than the controlateral tooth; or the formation of different layers of mineralised tissue that aggregate
together trough the years. Conclusion Apexification isn’t a static phenomenon and the apexified area undergoes
through the years to a conspicuous readjustment involving bone, apical root tissues and root filling material.
K
EYWORDS: Apexification-Apex closure-Calcium hydroxide.
University of L’Aquila (Italy)
*University of Rome “Tor Vergata”
E-mail: iaiaballes@yahoo.com
root canal system induces the formation of an apical
diaphragm of mineralised tissues by the apical
odontoblasts and cementoblasts. The calcium
hydroxide medication induces the formation of a
reparative fibrous tissue that progressively mineralises
and that has been defined through histological
evaluations [Ham et al, 1972; Steiner et al, 1971,
Gallusi, 1987] as cementoid or osteoid tissue, in some
cases described as bone, dentin, osteodentin or
cement. The variability in composition of the apical
diaphragm is explained by the presence of residues of
apical pulp tissue and of a still active epithelial sheath
[Frank, 1966; Feiglin, 1985].
Materials and methods
The apexification treatment was performed on 15
superior central incisors, in 7-9 years old patients,
affected by periapical pathology due to pulp necrosis
following dental trauma. The treatment has been
performed in two phases at a 6 months interval. The
aim of the first procedure was the achievement of an
efficient apical barrier. The procedures of the first
Introduction
Apexification is an endodontic treatment of non-vital
permanent teeth with open apex to induce the
formation of a calcified tissue and the closure of an
apex that hasn’t completed its physiological maturation
process [Frank, 1966].
The treatment is mostly performed on anterior
permanent teeth with open apex and pulp necrosis,
following a traumatic lesion, sometimes associated to
periapical abscess and vestibular sinus tract. Pulp
necrosis prevents the tooth to complete the
development of its radicular portion and to achieve the
physiological maturation of the apex. The apical
obliteration, final goal of the apexification treatment, is
the indispensable condition in order to obtain a correct
obturation of the root canal system and the healing of
the periapical infection. The application of calcium
hydroxide paste inserted with a lentulo spiral in the
phase included: isolation of the tooth with dental dam,
access to the endodontic spaces, shaping of the canal at
a working length 2 mm shorter than the actual canal
length and sodium hypochlorite alternated irrigation,
drying with sterile paper points, canal filling with
calcium hydroxide paste applied with a lentulo spiral
at the working length, obturation of the root canal with
ZOE paste.
The bacteria elimination from the canal system and
its filling with a highly antiseptic material help: the
immediate healing of the sinus tract, when present
(realised in 5-7 days), the progressive formation of a
reparative “scar” tissue (achieved in 5-6 months) and
the filling of the periapical bone gap, which is
completed over an average time of one year.
Control visits were scheduled once a month to
evaluate radiographically the treatment evolution.
The calcium hydroxide medication was repeated at a
3 months interval. It has been observed the progressive
formation of a radiopaque tissue occupying the
periapical area and, in some cases, frankly infiltrating
the apical space. Once the radiographs gave evidence of
the complete formation of a barrier at the calcium-
hydroxide/reparative tissue interface, the treatment
proceeded with the second phase according to the
following steps: isolation of the tooth with dental dam,
access to the endodontic spaces, removal of calcium
hydroxide, irrigation with sodium hypochlorite, drying
with sterile paper points, control of the presence and
consistence of the apical barrier with manual
instrument or paper coins, complete filling with gutta-
percha of the root canal system, final crown restoration.
The treated teeth were radiographed at six months
and then periodically once a year for a period of 7 and
13 years.
Results
1) In 6 cases the obtained healing determined the
formation of an apical barrier followed through the
years by a progressive development of the apical
portion with a final root length equal to the
contralateral tooth. The apical portion developed
physiologically (Figg. 1-5).
2) In 7 cases the apical closure was determined
by the formation of a cap tissue partially
invaginated, and apically by the development of a
further apical portion with a final root length
slightly shorter than the controlateral tooth and
completely mineralised at the following
radiographic controls (Figg. 6-9).
3) In 2 cases the healing shows the formation of
different layers of mineralised tissue that through
the years will aggregate in one mineralised tissue of
high thickness (Figg.10-14).
Of the 15 teeth treated have been shown three
cases, one for each healing pattern, to exemplify the
different kinds of apical closure.
I. BALLESIO ET AL.
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EUROPEAN JOURNAL OF PAEDIATRIC DENTISTRY • 1/2006
FIG. 1 - Coronal fracture of necrotic tooth 1.1 in 7 years old patient. FIG. 2 - The 2,5 years follow-up. Following apexification
the root length increased (when comparing the tooth 1.1 with the controlateral tooth) and a barrier formed apically to the root
filling material. Beyond this area it is possible to observe a radiolucent area and more apically another portion of root tissue.
FIG. 3 - At the years follow-up the radiolucent area apical to the root filling material and the a apical root tissue are more evident.
Discussion
The treatment of immature permanent teeth with
calcium hydroxide is fully described in literature
[Chawla,1986; Walia et al., 2000; Saad, 1988;
Caliskan,; 1997] and with high success rates
[Chawla,1986; Walia et al, 2000].
Recently [Shabahang et al., 1999; Hachmeister et al,
2002; Ham et al., 2005; Steinig et al., 2003; Ham et al.,
2005] the application of mineral trioxide aggregate has
been introduced to obtain the immediate apical closure
APICAL CLOSURE IN APEXIFICATION: LONG TERM RADIOGRAPHIC FOLLOW-UP
EUROPEAN JOURNAL OF PAEDIATRIC DENTISTRY • 1/2006
31
FIG. 4 - 7 years follow-up. The root length of 1.1 appears similar to 2.1 while the radiolucent area apical to the root filling
material is still visible. FIG. 5 - 13 years follow up. The radiographic evidences of the previous follow-ups are confirmed even after
many years and the apical root area has completed its physiological maturation. FIG. 6 - Coronal fracture of necrotic tooth 1.1 in a
7 years old patient. The tooth appears less developed than the contralateral tooth.
FIG. 7 - 2 years follow-up: due to the apexification, the root length has increased and apically to the root filling material a barrier is invaginating
in the root. FIG. 8 - 4 years follow-up: apically to the root filling material (which seems modified in its apical portion) a radiolucent area and
more apically a further portion of root tissue are evident. FIG. 9 - 9 years follow-up: the alteration of the apical portion of the root filling material
is evident; apically to this area there is a further root portion completely mineralised; 1.1 root length is slightly shorter than 2.1.
I. BALLESIO ET AL.
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EUROPEAN JOURNAL OF PAEDIATRIC DENTISTRY • 1/2006
FIG. 13 - 3 years follow-up. A higher mineralization of the apical root portion is evident, with consequent reduction of the
radiolucent area between the two radiopaque bridges. No changes are visible on the radiolucent area adjacent to the root filling
material that is slightly modified when compared to the previous follow-up. FIG. 14 - 10 year follow-up. The apical root portion
has completed its mineralization. It is still present, though reduced, the radiolucent area adjacent to the root filling material
that shows further modification. Root length is slightly shorter than that of the controlateral tooth.
FIG. 10 - Coronal fracture of necrotic tooth 2.1 in a 7,5 years old patient. FIG. 11 - 6 months follow-up. Calcium hydroxide
was placed with a lentulo spiral into the canal, which was 3-4 mm shorter than root length owing to a technical problem during
treatment. There are two radiopaque areas at the coronal and apical levels. FIG. 12 - 1,5 years follow-up. The two radiopaque
bridges are more evident. Two radiolucent areas are one adjacent to the root filling material and the other one between the
radiopaque bridges. Root length is similar to that of the contralateral tooth.
of the apex and rapidly proceed with the restoration.
This treatment, though it still does not have a long
follow-up as the calcium hydroxide [Chawla, 1991;
Theter, 1988].
The complete healing after apexification is achieved
in about 1±7 months [Kleier, 1991], depending on the
presence of radiolucency and periapical infection
[Kleier, 1991; Walia, 2000], the size of the apex
opening [Kleier, 1991; Walia, 2000] and the
development of inter-appointment symptoms [Kleier,
1991].
The radiographic aspect of the apical closure
obtained after apexification treatment has been
classified [Frank, 1966; Feiglin, 1985] in 4 clinical
types according to the presence or absence of the
Hertwig epithelial sheath and its relationship with the
apical residues of the pulp tissue. If the sheath is still
present and the apical odontoblasts are still vital, the
root will develop normally with a physiological
process of apexogenesis (Type 1). If the Hertwig
sheath is still vital but are missing vital odontoblasts,
the root will lengthen without a physiological
maturation of the apex (Type 2). When the Hertwig
sheath and the odontoblasts are both non-vital, the
healing can only take place with the formation of a cap
of mineralised tissue produced by osteoblasts and
cementoblasts activity either at the apex level (Type 3)
or coronal to the apex (Type 4).
The calcified bridge formed following apexification
is a porous structure [Walia et al., 2000]. Follow-up
after 6-12 years shows that this structure remains the
same, consolidates or decreases [Chawla, 1991].
In our experience, the type of apical closure seems
related to the following factors:
a) the kind of contact between calcium hydroxide
and apical tissue;
b) vitality and potentiality of the epithelial sheath.
The healing patterns obtained allow some
considerations.
In all cases there was a chronic periradicular
pathology often associated with abscess and vestibular
sinus tract. The final root length of the treated teeth,
though initially highly reduced, was slightly shorter
than that of the contralateral tooth and in some cases
aabout the same. This healing pattern does not seem
related to the proximity of calcium hydroxide to the
apical area. In no case a physiological maturation
process has been observed as time went on, nor in
radiographic anatomy. These findings show that,
though was still present a guide (Hertwig sheath) to the
root development, the specialised cells (odontoblasts)
were not available, and thus not able to immediately
perform the instructions. These were completed over a
longer period of time by mesodermic cells
differentiated under the influence of the epithelial
sheath. The final result was a root development that
never appeared absolutely physiological, though it
determined the lengthening of the apical portion.
The site of the formation of the first apical cap seems
directly related to the level of insertion of calcium
hydroxide and to its contact with the apical tissue. It is
also necessary to underline that the aspect and the
quality of the apical obliteration is highlighted in its
form when radiopaque root filling material has contact
with the cap. The filling material works as contrast
medium highlighting its interface with the apical
barrier. Radiographs often show a small radiolucent
area between the root filling material and the apical
cap, that remains visible over the years. The meaning
of this area cannot be referred to a gap in the
obturation, on the contrary it is due to the presence of
a reparative tissue that can be made radiopaque with
difficulty because of the colonisation of cementoblasts
and osteoblasts; since their pattern of mineralization
goes from the periphery to the centre of the canal and
the already mineralised tissues obstructs the cell
activity and slows down the progression of the
mineralization process.
When comparing radiographs, the apexification does
not appear a static phenomenon and it is characterised
by a continuous modification of the apexified area over
the years. In fact it is evident a readjustment of the
bone structure and the apical tissues that continue their
development according to the instructions given by the
epithelial sheath; even the filling material undergoes a
certain amount of modifications.
Conclusions
Apexification isn ot a static phenomenon. The
apexified area undergoes a conspicuous readjustment
through the years, involving bone and apical root
tissues until the epithelial sheath instructions are
completed. Further readjustments involve the root
filling material.
References
Caliskan MK, Turkun M. Periapical repair and apical closure of a
pulpless tooth using calcium hydroxide. Oral Surg Oral Med
Oral Patho Oral Radiol Endod, 1997; 84: 683-687
Chawla HS. Apical closure in a nonvital permanent tooth using one
Ca (OH)2 dressing. ASDC J Dent Child, 1986; 53: 44-47
Chawla HS. Apexification: follow-up after 6-12 years. J Ind Soc
Pedod Prev Dent, 1991; 8: 38-40
Feiglin B. Differences in apex formation during apexification with
calcium hydroxide paste. Endod Dent Traumatol, 1985;1:195-9.
Frank AL. Therapy for the divergent pulpless tooth by continued
apical formation. J Am DenT Assoc, 1966; 72: 87-8
Gallusi G. Elements of Pedodontics. Padova: Piccin; 1987
Hachmeister DR, Schindler WG, Walker WA 3rd, Thomas DD.
The sealing ability and retention characteristics of mineral
trioxide aggregate in a model of apexification. J Endod, 2002;
28: 386-390
APICAL CLOSURE IN APEXIFICATION: LONG TERM RADIOGRAPHIC FOLLOW-UP
EUROPEAN JOURNAL OF PAEDIATRIC DENTISTRY • 1/2006
33
Ham JW, Patterson SS, Mitchell DF. Induced apical closure of
immature pulpless teeth in monkeys. Oral Surg 1972;23:438-49.
Ham KA, Witherspoon DE, Gutmann JL, Ravindranath S, Gait TC,
Opperman LA. In-vitro evaluation of microleakage of an
orthograde apical plug of mineral trioxide aggregate in
permanent teeth with simulated immature apices J Endod,
2005; 31: 117-9
Ham KA, Witherspoon DE, Gutmann JL, Ravindranath S, Gait TC,
Opperman LA. Preliminary evaluation of BMP-2 expression
and histological characteristics during apexification with
calcium hydroxide and mineral trioxide aggregate J Endod,
2005; 31: 275-279
Kleier DJ, Barr ES. A Study of endodontically apexified teeth.
Endod Dent Traumatol, 1991; 7(3): 112-7
Saad AY. Calcium hydroxide and apexogenesis. Oral Surg Oral
Med Oral Patho Oral Radiol Endod, 1988; 66: 499-501
Shabahang S, Torabinejad M, Boyne PP, Abedi H, McMillan P. A
comparative study of root end- induction using osteogenig
protein-1, calcium hydordide, and mineral trioxide aggregate in
dogs. J Endod, 1999; 25: 1-5
Steiner JC, Van Hassel HJ. Experimental root apexification in
primates. Oral Surg Oral Med Oral Pathol, 1971; 31:409-
15
Steinig TH, Regan JD, Gutmann JL. The use and predictable
placement of mineral trioxide aggregate in one-visit
apexification cases. Aust Endod J, 2003; 29: 34-42
Thater M, Marechaux SC. Induced root apexification following
traumatic injuries of the pulp in children: follow-up study.
ASDC J Dent Child, 1988; 55: 190-195
Walia T, Chawla HS, Gauba K. Management of wide open apices
in non-vital permanent teeth with Ca(OH)2 paste. J Clin Pediatr
Dent, 2000; 25: 51-6
I. BALLESIO ET AL.
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