Bilateral alveolar bone grafting: a report of 55 consecutively-treated patients.

Abstract

A retrospective study was undertaken to evaluate the long-term results of bilateral alveolar bone grafting carried out at Great Ormond Street Hospital from 1983 to 1993. Fifty-five consecutive complete bilateral cleft lip and palate patients (36 males and 19 females) who had the operation were included in this study. The total number of cleft sites was 110. At the time of alveolar bone grafting, the mean age of the patients was 12.3 years with a range of 8.4-19.9 years. Cancellous bone from the iliac crest was grafted into the alveolar cleft areas. The cleft sites were studied in two groups according to whether the cleft canine had erupted prior to bone grafting or not. The erupted canine group was composed of 43 cleft sites and the unerupted canine group of 67 sites. At the time of this study, the cleft canine had subsequently erupted at 101 sites. Anterior occlusal radiographs were taken before and after bone grafting. The minimum period of observation after alveolar bone grafting was one year. Criteria described previously were utilized to assess the height of the interdental septum. The results show that bone grafting before canine eruption has a higher clinical success rate compared with that carried out after canine eruption. The critical variable affecting the quality of bilateral alveolar bone grafting is the timing of the surgery.

Full text

Page 1

Introduction
Facial dysmorphology in complete bilateral cleft
lip and palate is often severe. The residual alveolar
cleft is considered to be the main obstacle to ob-
taining optimum results (Bergland et al., 1986).
Alveolar bone grafting in conjunction with ortho-
dontic treatment has become a well accepted strat-
egy. Secondary alveolar bone grafting helps to
stabilize the maxillary segments and the mobile
pre-maxilla in bilateral cleft cases (Matthews
et al., 1970; Boyne and Sands, 1972, 1976; Åbyholm
et al., 1981; Braun and Sotereanos, 1981; Sindet-
Pedersen and Enemark, 1985; Paulin et al., 1988;
Amanat and Langdon, 1991), to allow eruption
of teeth into the cleft and to achieve orthodontic
movement of teeth adjacent to the cleft site so
as to obtain a non-prosthodontic rehabilitation
(Johanson et al., 1974; Boyne and Sands, 1976;
Braun and Sotereanos, 1981; Bergland et al.,
1986; Amanat and Langdon, 1991). Compared
with the unilateral cleft, bilateral cleft patients
have several characteristics (Eppley et al., 1986),
especially with the mobile pre-maxilla (Bergland
et al., 1986). These features make bilateral bone
grafting more difficult than unilateral grafting.
This difference might affect the results obtained
by bone grafting between the two groups. Some
researchers have found the morbidity of bone
graft to be greater in patients with bilateral cleft
lip and palate (Hall and Posnick, 1983) and poor
immobilization of the pre-maxilla in the post-
operative phase contributes to the unfavourable
consequence in bilateral cases (Åbyholm et al.,
1981). It is therefore necessary to study bilateral
cleft patients separately.
Timing and complications of alveolar bone
grafting are two aspects of wide concern. How-
ever, surgical procedures for grafting an alveolar
cleft defect should aim toward optimal physio-
logical function, and lead to minimal interference
and impairment of growth and development in
the maxillofacial complex (El Deeb, 1990). In the
1970s, studies appeared suggesting that if bone
European Journal of Orthodontics 20 (1998) 299–307
 1998 European Orthodontic Society
Bilateral alveolar bone grafting:
a report of 55 consecutively-treated patients
Yi-Lin Jia, David R. James and Michael Mars
Great Ormond Street Hospital for Children NHS Trust, London, UK
SUMMARY A retrospective study was undertaken to evaluate the long-term results of
bilateral alveolar bone grafting carried out at Great Ormond Street Hospital from 1983 to
1993. Fifty-five consecutive complete bilateral cleft lip and palate patients (36 males and
19 females) who had the operation were included in this study. The total number of cleft
sites was 110. At the time of alveolar bone grafting, the mean age of the patients was
12.3 years with a range of 8.4–19.9 years. Cancellous bone from the iliac crest was grafted
into the alveolar cleft areas. The cleft sites were studied in two groups according to whether
the cleft canine had erupted prior to bone grafting or not. The erupted canine group was
composed of 43 cleft sites and the unerupted canine group of 67 sites. At the time of this
study, the cleft canine had subsequently erupted at 101 sites. Anterior occlusal radiographs
were taken before and after bone grafting. The minimum period of observation after alveolar
bone grafting was one year. Criteria described previously were utilized to assess the height
of the interdental septum.
The results show that bone grafting before canine eruption has a higher clinical success
rate compared with that carried out after canine eruption. The critical variable affecting the
quality of bilateral alveolar bone grafting is the timing of the surgery.

Page 2

graft repair of alveolar clefts was delayed until
the age of the mixed dentition, good function
would result, and there would be much less effect
on growth and development (Troxell et al., 1982).
In order to minimize the negative influence on
maxillary growth, most authors, perhaps with the
exception of Rosenstein et al. (1982), agree that
the optimal age for bone grafting is during the
mixed dentition (Boyne and Sands, 1972, 1976;
Koberg, 1973; Åbyholm et al., 1981; Nordin et al.,
1983; Enemark et al., 1985; Bergland et al., 1986;
Amanat and Langdon, 1991; Freihofer et al., 1993).
Complications of alveolar bone grafting have been
discussed (Bergland et al., 1986; Sindet-Pedersen
and Enemark, 1988; Amanat and Langdon, 1991).
The purpose of this investigation is to report
the results of treatment of bilateral clefts in
patients. It was also hoped that a factor(s) could
be identified which improved the outcome of
such treatments.
Subjects
The subjects in this study comprised 57 bilateral
complete cleft lip and palate patients with
grafting carried out at Great Ormond Street
Hospital, London, England from 1983 to 1993.
Two patients without radiographs at one or
more years post-operatively were excluded. In
this study, 55 patients (49 Caucasians, one Afro-
Caribbean, four Asians, and one Oriental) with
anterior occlusal radiographs at least 1 year post-
alveolar bone grafting were included. The sex
distribution was 36 males and 19 females. The
total number of cleft sites was 110. The age range
at the time of alveolar bone grafting was 8.4–19.9
years, mean 12.2 years.
The cleft sites were studied in two groups ac-
cording to whether the cleft canine had erupted or
not when alveolar bone grafting was performed.
1. The erupted canine group comprised 43 cleft
sites. The age range of the patients at the time
of the bone grafting was 10.5–19.9 years, mean
14.1 years.
2. The unerupted canine group comprised 67
cleft sites. The age range of the patients at the
time of the bone grafting was 8.4–13.9 years,
mean 10.9 years.
Method
Clinical management
Orthodontics, prior to and after the alveolar bone
grafting, was undertaken. Pre-orthodontic treat-
ment included maxillary expansion, proclination
of upper incisors and closure of the space between
upper incisors. Cancellous bone from the iliac
crest was grafted into the alveolar clefts. Anter-
ior occlusal radiographs were taken pre- and post-
operatively. Follow-up radiographs were taken
regularly. The evaluation was based on anterior
occlusal radiographs. The follow-up period was
between 1 and 10 years. The mean observation
period was 3.8 years for the erupted canine
group and 3.5 years for the unerupted canine
group.
The criteria of evaluation
The height of the interdental septum was re-
corded according to the criteria of Bergland et al.
(1986):
Type I:
Type II: height at least 3/4 of normal;
Type III: height less than 3/4 of normal;
Type IV: failure: no continuous bony bridge
across the cleft achieved.
height approximately normal;
Complications were also recorded.
Results
The eruption of the cleft canine
The cleft canine had erupted at 43 (39.1 per cent)
sites and had not erupted at 67 (60.9 per cent)
sites when the alveolar bone grafting was carried
out. One-hundred-and-one (91.8 per cent) cleft
canines had erupted at the time of this study.
Nine (8.2 per cent) cleft canines remained un-
erupted when this investigation was undertaken.
Radiographs showed that five (4.6 per cent) of
the unerupted cleft canines were horizontally
impacted and the long axis of the remaining four
(3.6 per cent) canines was normal. The patients
with normal long axis of unerupted canine were
under 12 years of age.
300
Y-L. JIA ET AL.

Page 3

The height of the interdental septum
The height of the interdental septum was evalu-
ated after the cleft canine had fully erupted. One-
hundred-and-one cleft sites with fully erupted
canines were evaluated.
The whole sample
In complete bilateral clefts, the clinical success
rate was 83 per cent (types I and II) and the
clinical failure rate (types III and IV) was 17 per
cent. The results are shown in Table 1.
The unerupted canine group
Ninety-five per cent of cleft sites were clinically
successful (types I and II) and 5 per cent of cleft
sites were clinically unsuccessful in the unerupted
canine group (Table 2).
The erupted canine group
Sixty-seven per cent of cleft sites were clinically
successful (types I and II), whereas 33 per cent
of cleft sites were clinically unsuccessful in the
erupted canine group (Table 2).
Complications
Four patients had infection of both graft sites
resulting in complete failure of the alveolar bone
graft. Three patients were in the erupted canine
group and one patient was in the unerupted
canine group. The oral hygiene of these patients
was noted to be poor post-operatively.
Minor wound dehiscences appeared at one graft
site. The cleft canine had not erupted at the time
of alveolar bone grafting. Poor oral hygiene was
noted as in the failed cases.
Three graft sites developed proliferative granu-
lation tissue in two patients. One patient was in
BILATERAL ALVEOLAR BONE GRAFTING
301
Table 1
Analysis of the total sample of bilateral clefts.
Cleft sites
Canine in final occlusion
(101)
Graft type
Type I67 (66%)
84 (83%) Clinically successful
Type II17 (17%)
Type III6 ( 6%)
17 (17%) Clinically unsuccessful
Failure11 (11%)






Table 2
Analysis of the cleft sites in the two different bone grafting groups.
Graft typeClefts grafted after
eruption of canine
(43)
Clefts grafted before
eruption of canine
(58)
Type I 16 (37%) 51 (88%)
29 (67%)55 (95%)
Type II13 (30%) 4 ( 7%)
Type III 5 (12%)1 ( 2%)
14 (33%) 3 ( 5%)
Failure9 (21%)2 ( 3%)













Page 4

the erupted canine group and the other was in
the unerupted canine group.
Two patients showed exposed bone at four
cleft sites after the operation. Ten years after
the bone grafting, the radiographs showed that
there was one failure site, two type III sites, and
one type II site.
Donor site infection was found in two patients
in the erupted canine group.
Discussion
Pre- and post-operative orthodontics
The main purpose of pre-operative orthodontics
is to correct displaced maxillary segments and to
provide improved access for the maxillofacial
surgeon to perform bone grafting. This proced-
ure is especially important in bilateral cleft cases.
Nearly all patients in this study had undergone
orthodontic treatment before alveolar bone graft-
ing. In bilateral clefts, often, the upper incisors
are retroinclined and both the buccal segments
are collapsed. It is relatively easy to procline the
upper incisors using removable appliances.
Palatal expansion was carried out with remov-
able appliances, but mainly with the quad-helix
appliance. Expansion before the bone graft
widens the cleft and thereby facilitates closure of
the nasal mucosa (Hall and Posnick, 1983).
In bilateral cleft patients, a movable pre-
maxilla may jeopardize the immediate healing
process (Bergland et al., 1986). In this study, the
pre-maxilla was immobilized for 3 months post-
operatively so as to minimize the risk, by using
fixed appliances. After alveolar bone grafting,
ideally the cleft was clinically undetectable and
post-surgical orthodontic treatment is similar to
that obtaining in routine orthodontics. In some
crowded cases, extraction of two malformed or
poorly positioned upper lateral incisors seems
more reasonable than the extraction of first pre-
molars, because the malformation of the upper
lateral incisors is relatively common in cleft lip
and palate patients. During the post-operative
orthodontic period, correct midline, and good
arch form were obtained by moving the upper
canines mesially. The crown of the canine can be
modified to meet aesthetic requirements.
Cleft canine eruption
At the time of this investigation, most of the cleft
canines had erupted. Only a few cleft canines
were impacted. Radiographs showed that the
long axis of these impacted canines was horiz-
ontal prior to the bone grafting. Spontaneous
eruption could not be expected. Compared to
15 per cent retention of canines in bilateral clefts
(Enemark et al., 1987), cleft canine retention
was relatively rare in this study. Four further
cases demonstrated cleft canines which had not
erupted at the time of the study. In these cases,
however, the radiographs showed that the long
axis of the canines appeared normal and the
age of these patients was under 12 years. It
could be anticipated that these canines might
erupt spontaneously in the future. According
to this study, these results demonstrate that the
canine retention was mainly due to the abnormal
long axis direction, rather than the influence of
alveolar bone grafting and occurred in only five
cases.
Bone height at cleft site (Bergland et al.,
1986, criteria)
The height of the interdental septum after alveolar
bone grafting was considered to be the main in-
dication of successful bone grafting. Long-term
follow-up is needed to determine the final levels
of bone associated with fully erupted canines
(El Deeb, 1990). The osseous healing of trans-
plants evaluated on intra-oral radiographs may
be regarded as terminated within 6 months post-
operatively in 80 per cent of the patients (Johanson
et al., 1974). In this study, the minimum observa-
tion period was 1 year after alveolar bone graft-
ing. The results in the whole sample showed that
the clinical success rate in complete bilateral
clefts was high (Table 1) and comparable with
other studies (Bergland et al., 1986; Amanat and
Langdon, 1991). However, this result is the com-
bined outcome of bilateral cleft lip and palate
patients treated before and after eruption of the
cleft canine.
Several factors which might affect the final
results of the alveolar bone grafting were in-
vestigated.
302
Y-L. JIA ET AL.

Page 5

The state of eruption of the cleft canine at the time
of bone grafting. Significant differences emerge
when the whole sample is divided for study into
two groups: the erupted canine group and the
unerupted canine group (Table 2 and Figure 1).
The unerupted canine group had a significantly
higher clinical success rate than the erupted canine
group. The type I (approximately normal inter-
dental septal height) graft rate was much higher
in the unerupted canine group than in the erupted
canine group. The density of the bone in the cleft
areas was the same as normal alveolar bone. The
results suggest that bone grafting performed
before canine eruption is highly successful and
the critical variable affecting the quality of bilat-
eral alveolar bone grafting is the timing of the
surgery. This is in agreement with other studies
(Bergland et al., 1986; Amanat and Langdon,
1991). The results of this study support the find-
ings that bone grafting performed before canine
eruption produces a better outcome than if the
operation is performed after canine eruption.
Figure 2 shows the clinical appearance and
post-operative radiographs of failed alveolar
bone grafts after the canine had erupted, and
Figure 3 shows the clinical appearance, and pre-
and post-operative radiographs of a clinically
successful case where bone grafting was under-
taken before canine eruption.
BILATERAL ALVEOLAR BONE GRAFTING
303
Figure 1
assessed by height of interdental septum, I + II: clinically
successful; III + IV: clinically unsuccessful. (A) Combined
early and late alveolar bone grafting (B + C pooled result).
(B) Alveolar bone grafting before canine eruption. (C)
Alveolar bone grafting after canine eruption.
Success of alveolar bone grafting in BCLP cases,
A
B
C
D
Figure 2
erupted. (A) Clinical appearance. (B, C, and D) Post-
operative radiographs.
Failed alveolar bone grafting after the canine had