| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Orthodontic Department, York District Hospital, Wigginton Road, York YO31 8HE, U.K.
Department of Orthodontics, Leeds Dental Institute, Clarendon Way, Leeds LS2 9LU, U.K.
 |
Abstract |
|---|
 Top Abstract IntroductionMethodsResultsDiscussionConclusionsReferences |
|---|
The subjects were 109 patients who had secondary alveolar bone grafting between 1.9.91. and 31.8.96. The quality of outcome was assessed using a four-point radiographic scale from occlusal radiographs taken at least 3 months post-operatively: Grade 1 = >75 per cent bony in-fill, Grade 2 = 50-75 per cent bony in-fill, Grade 3 = <50 per cent bony infill, and Grade 4 = no bony bridge
The radiographic assessment scale was assessed for reliability: inter-examiner weighted kappa = 0.622-0.715 and intra-examiner = 0.818-0.943. Grade 1 results were achieved in 63.2 per cent patients receiving orthodontic expansion and in 40 per cent without expansion before grafting.
The four-point radiographic scale described is a useful tool in assessing alveolar bone grafting. Orthodontic expansion
Key words: Inter-centre, Orthodontic Expansion, Secondary Alveolar Bone Grafting
|
Introduction |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionConclusionsReferences |
|---|
, 1988). The surgical technique was described by Boyne and Sands (1972) and this has largely been accepted as the standard approach. These authors
recommend raising mucoperiosteal flaps to access the cleft area, with periosteal flaps raised from
the bony walls of the cleft to repair the floor of the nose. They advocate that autogenous bone
chips harvested from the iliac crest, are packed into the cleft defect, and the mucosal flaps are
closed to complete the procedure.
Ideally, the technique is performed early enough to allow eruption of the permanent canine into
the grafted bone (Bergland et al., 1986; Brattstrom
and McWilliam, 1989). Cancellous bone becomes fully integrated with the maxilla
and is preferable to cortical and costochondral grafts (Borstlap et al.,1990), which may inhibit tooth eruption. However, Witsenburg and Freihofer (1990) suggest otherwise. In a study of 17 cases using autogenous rib grafts, with a
mean follow-up of 76 months, these authors showed all permanent canines to have erupted
normally.
Assessing the success of the graft radiographically has previously been carried out on a long-term
basis. Bergland et al. (1986) focused on the height of the
interdental septum adjacent to the erupted canine, and used radiographs taken at least 1 year after
surgery for the assessment. In 64 per cent of 450 grafted clefts, a normal height of inter-dental
septum was achieved and the cleft space was closed in 90 per cent of cases.
Long et al. (1995), measured contours of the grafted bone from
radiographs of 46 cleft sites in order to determine the level of bony fill. They used radiographs
taken at least 6 months after surgery and had a mean follow-up time of 3.1 years. Their
sample achieved a bony bridge in 91 per dent of the cases and the mean height of the alveolar
crest was 93 per cent of the anatomic root length in the proximal segment and 96 per cent of the
anatomic root length in the distal segment. Rosenstein et al. (1997) have shown two-dimensional radiography to be as effective as CAT scans in
determining the bony coverage of teeth adjacent to the cleft site.
The aims of this study were to assess the outcome of secondary alveolar bone grafting in five
units in Yorkshire and, if differences in outcome existed, attempt to identify contributing factors.
The outcome of alveolar bone grafting was assessed using a recently developed
radiographically-based scale (Kindelan et al., 1997), which is
described later. It also provided an opportunity to assess the effect of presurgical orthodontic
expansion on the outcome, as this provision varied between units. The frequency of bone grafting
by the surgeons was assessed and the implications of low volume operators considered.
|
Methods |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionConclusionsReferences |
|---|
Recordings were made of the type of cleft involved, the age at the time of grafting, the timing of
radiographs in relation to surgery, the identity of the operator, and the surgical technique used.
Pre- and post-operative radiographs were examined to determine the outcome of the surgery. The
majority of radiographs were occlusal views, with 18 sites having orthopantomograms
(OPT's) pre-operatively and nine post-operatively. Patients with only OPT's
post-operatively were excluded from the analysis, as image quality is frequently poor. However,
nine patients with OPT's per-operatively were included in the analysis. There were 24
sites
with no post-operative radiographs. For the analysis, patients whose only post-operative
radiographs were taken within 3 months of the surgery were excluded, as further bony resorption
can effect the final outcome (Lija et al., 1987). The
pre-operative
radiographs of all the subjects were taken a mean of 7.7 months prior to surgery (range
1–38 months), and the post-operative radiographs were a mean of 8.1 months
after surgery (range 1–29 months).
The radiographs were assessed using a previously developed assessment scale (Kindelan et al., 1997). This is as follows:
Enemark et al.(1987) recommended the use of a similar scale,
based on the height of the interdental bone in the cleft area. However, this has the disadvantage
that areas devoid of bone adjacent to the apex are not accounted for. Examples of results
classified as grades 1–3 are shown in Figures 1, 2, 3. The pre and post-operative radiographs were
viewed simultaneously to determine the grade of outcome for all patients with complete
radiographic records. They were assessed on two separate occasions, at least 1 week apart.
Where there was disagreement between the recordings, the radiographs were re-examined to
determine the appropriate result.
|
|
|
),
and the values are displayed inTable 1.
|
), which ascribed the following levels of agreement to the Kappa values;
These results show the level of intra-examiner agreement to be almost perfect, and the inter-examiner agreement to be substantial.
The frequency of presurgical orthodontics was significant. Two units routinely used orthodontic expansion if appropriate prior to bone grafting and one routinely carried out no orthodontic expansion. The other two units varied their approach depending upon which orthodontic consultant was involved in the patient's management. This study therefore provided an opportunity to compare the results of secondary alveolar bone grafting with and without presurgical orthodontic expansion.
|
Results |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionConclusionsReferences |
|---|
|
|
). Three units exclusively used this standard
technique, and 93 per cent of all the bone grafts in this review were performed in that manner. At
unit A, all but one graft utilized the standard technique and one was performed simultaneously
with a maxillary osteotomy. At unit D some variation in technique existed, 76 per cent were of
the
standard technique, 15 per cent utilized iliac crest fascia to repair the floor of nose and the
remaining 9 per cent were carried out in conjunction with an osteotomy or using the inferior
turbinate to repair the floor of nose. All operators harvested autogenous cancellous bone chips
from the iliac crest. At unit B for approximately half the cases the bone was harvested using a
trephine, although this has previously been shown not to affect the outcome assessed
radiographically (McCanny and Roberts-Harry, 1998). Units B and C
performed the grafts in bilateral cases in two stages.
A total of 12 surgeons in the five units were involved in alveolar bone grafting (Table
4). Only one unit had a single surgeon, three units performed joint
procedures with two operators. The remaining unit had three surgeons each operating
independently. The centres with joint teams tended to have one surgeon harvesting the bone,
while the second surgeon prepared the graft site. It was not always clear from the operating notes
which surgeon had which duty and the figures of sites per surgeon may, therefore, be falsely
elevated. The mean number of sites grafted over the 5 years is 10.6 per surgeon,
although there was wide variation, with two surgeons performing 33 and 35, respectively, and
two surgeons performing only 1 bone graft each.
Statistical Analysis
Results for all unilateral cases were entered, and the bilateral cases had one site randomly
selected
for analysis to satisfy the assumption of independence between sites. This resulted in 78 sites
being analysed (59 unilateral and 19 bilateral) and the results for each unit are displayed inTable 5.
|
|
|
|
Discussion |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionConclusionsReferences |
|---|
The relationship between the output and outcome for several general surgical procedures has
been
documented (Hannan et al., 1989). The evidence suggests that
operators who perform a high number of a given surgical procedure will perform it to a higher
standard than a low volume operator. Studies relating to cleft lip and palate care support this
view
(Shaw et al., 1992) and attempts have been made to influence
cleft care in the light of these findings (Shaw et al., 1996),
particularly following the recent CSAG report (Department of Health, 1998). Hannan et al. (1989) also showed that high
volume hospitals performed better than low volume hospitals in some general surgical
procedures.
This point was previously made by Roos et al. (1986) who were
in favour of centralization of general surgical services in Canada, although they showed the
single
most important factor in determining the level of post-surgical complications was the
operators's surgical experience. The results of the present study show that centre B, the
only centre with one dedicated surgeon, had the highest percentage of grade 1 results, although
the difference was not statistically significant.
Williams et al. (1994) showed that one third of cleft surgeons in
England and Wales performed less than five primary cleft repairs per year. This evidence must be
evaluated against the knowledge that in 1994 the Standing Dental Advisory Committee to the
Clinical Standards Advisory Group, suggested that a caseload of 40–50 cleft repairs each
year would be desirable (Department of Health, 1994), although this was
revised to 30 cases per year. It would seem logical to apply these figures to secondary alveolar
bone grafting. Therefore, based on the results of this review, it may be appropriate for the bone
grafting for the five units to be carried out by one surgeon or surgical team. Since this data was
collected the five units are moving towards two nominated surgeons working as a dedicated
team.
Asher-McDade and Shaw (1990) carried out a survey of 45 cleft teams in
the United Kingdom. They found that centres had, on average, 10.2 new cleft patients
per year with a range of 2–40 per year. Across the five units included in this study,
approximately 60 new clefts are born each year, about 55 per cent of which would require bone
grafts. Over a 5-year period this would be approximately 165 bone grafts. There were 128 grafts
in the 5 years covered in this study, which suggests some patients may not have received bone
grafting, because they had been lost to follow-up. Indeed, because of the significant age range in
the sample it may be that more patients have been missed, and initial plans should be based on a
`catch-up's philosophy with greater numbers planned for.
Asher-McDade and Shaw (1990) also showed that over 70 per cent of
cleft teams they surveyed combined orthodontic expansion with secondary alveolar bone
grafting.
The evidence of this review was that approximately half the patients were not expanded prior to
the surgery. The difference in results obtained when orthodontic expansion was used was quite
striking. Sixty-three per cent of orthodontically-expanded cases achieved a grade 1 result (i.e.
greater than 75 per cent bony in-fill of the clef). However, only 40 per cent of the non-expanded
cases achieved grade 1 result. This difference may be related to the improved surgical access
following orthodontic expansion, particularly in facilitating closure of the floor of the nose. An
improved repair to the floor of the nose would allow a more satisfactory placement of grafted
bone chips, which may otherwise be lost per-nasally (Boyne and Sands, 1972).
This study sample displayed no demonstrable difference in outcome of bone grafting when
considering the age of the patient or the complexity of the cleft. These factors have previously
been shown to have an influence on the result of grafting, with younger patients (Paulin et al., 1988; Brattström and McWilliam, 1989) and unilateral clefts (Sindet-Pedersen and Enemark, 1985)
having better results. The results in this review may have been influenced by the large number of
variables; different hospitals, with different surgeons, variable provision of orthodontic
expansion,
and the large age range will all have contributed to make the demonstration of differences
difficult. The fact that relatively small groups were sampled only serves to compound these
problems. A centralized care model should help to improve the quality of material available for
research.
In comparison to previously reported studies of alveolar bone grafting, these results are
favourable. Amanat and Langdon (1991), Long et al. (1995), and Kindelan et al. (1997)
reported between 5 and 9 per cent of cases in which there had been failure to form a complete
bony bridge across the cleft. This study demonstrated approximately 50, 30, and 20 per cent of
grades 1, 2, and 3, respectively, with no complete failure of the grafts.
This study was retrospective and approximately 15 per cent of the 128 grafted sites had to be excluded from the final analysis, mainly due to incomplete radiographic records. This may have introduced bias into the sample, as cases which progressed unfavourably may not have been radiographed, thus falsely elevating a unit's overall performance. It is planned to prospectively study the provision of alveolar bone grafting in the Yorkshire region, with all units adhering to a standardised protocol of data collection.
|
Conclusions |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionConclusionsReferences |
|---|
|
|
Acknowledgments |
|---|
|
References |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionConclusionsReferences |
|---|
Asher-McDade, C. and Shaw, W. C. (1990) Current cleft lip and palate management in the United Kingdom, British Journal of Plastic Surgery, 43, 318–321.[Medline]
Bergland, O., Semb, G. and Abyholm, F. E. (1986) Elimination of the residual alveolar cleft by secondary bone grafting and subsequent orthodontic treatment, Cleft Palate Journal, 23, 175–205.[Medline]
Borstlap, W. A., Heidbuchel, K. L., Freihofer, H. P. and Kuijpers-Jagtman, A. M. (1990) Early secondary bone grafting of alveolar cleft defects. A comparison between chin and rib grafts, Journal of Cranio-Maxillo-Facial Surgery, 18, 201–205.
Boyne, P. and Sands, N. (1972) Secondary bone grafting of residual alveolar and palatal clefts, Journal of Oral Surgery, 30, 87–92.
Brattstrom, V. and McWilliam, J. (1989) The influence
of bone grafting age on dental abnormalities and alveolar bone height in patients with unilateral
cleft lip and palate, European Journal of Orthodontics, 11, 351–358.
Cohen, J. (1960) A coefficient for agreement for nominal scales, Educational and Psychological Measurement, 20, 37–46.
Department of Health (1994) Report of the Standing Dental Advisory Committee to the Clinical Standards Advisory Group, HMSO, London.
Department of Health (1998) Report of a CSAG Committee (Cleft Lip and/or Palate), HMSO, London.
Enemark, H., Krantz-Simonsen, E. and Schramm, J. E. (1985) Secondary bone grafting in unilateral cleft lip and palate patients: indications and treatment procedure, International Journal of Oral Surgery, 14, 2–10.[Medline]
Enemark, H., Sindet-Pedersen, S. and Bundgaard, M. (1987) Longterm results after secondary bone grafting of alveolar clefts, Journal of Oral and Maxillofacial Surgery, 45, 913–918.[Medline]
Enemark, H., Sindet-Pedersen, S., Bundgaard, M. and Simonsen, E. K. (1988) Combined orthodontic-surgical treatment of alveolar clefts, Annals of Plastic Surgery, 21, 127–133.[Medline]
Hannan, E. L., O'Donnell, J. F., Kilburn, H., Bernard, H. R. and Yazici, A. (1989) Investigation of the relationship between volume and mortality for surgical procedures in New York State hospitals, Journal of the American Medical Association, 262, 503–510.[Abstract]
Kindelan, J. D., Nashed, R. R. and Bromige, M. R. (1997) Radiographic assessment of secondary autogenous alveolar bone grafting in cleft lip and palate patients, Cleft Palate-Craniofacial Journal, 34, 195–198.
Landis, J. R. and Koch, G. G. (1977) The measurement of observer agreement for categorical data, Biometrics, 33, 159–174.[Medline]
Lija, J., Möller, M., Friede, H., Lauritzen, C., Petterson, L. and Johanson, B. (1987) Bone grafting at the stage of mixed dentition in cleft lip and palate patients, Scandinavian Journal of Plastic Surgery, 21, 73–79.
Long, R., Spangler, B. and Yow, M. (1995) Cleft width and secondary alveolar bone graft success, Cleft Palate-Craniofacial Journal, 32, 420–427.
McCanny, C. and Roberts-Harry, D. (1998) A comparison of two different bone harvesting techniques for secondary alveolar bone grafting in patients with cleft lip and palate, Cleft Palate-Craniofacial Journal, 35, 442–446.
Paulin, G., Astrand, P., Rosenquist, J. B. and Bartholdson, L. (1988) Intermediate bone grafting of alveolar clefts, Journal of Cranio-Maxillofacial Surgery, 16, 2–7.
Roos, L. L., Cageorge, S. M., Roos, N. P. and Danzinger, R. (1986) Centralization, certification and monitoring, Medical Care, 24, 1044–1066.[Medline]
Rosenstein, S. W., Long, R. E., Dado, D. V., Vinson, B. and Alder, M. E. (1997 Comparison of 2-D calculations from periapical and occlusal radiographs versus 3-D calculations from CAT scans in determining bone support for cleft adjacent teeth following early alveolar bone grafts, Cleft-Palate-Craniofacial Journal, 34, 199–205.
Shaw, W. C., Dahl, E., Asher-McDade, C., Brattstrom, V., Mars, M., McWilliam, J., Molsted, K., Plint, D., Prahl-Andersen, B., Roberts, C., Semb, G. and The, R. (1992) A six-center international study of treatment outcome in patients with clefts of the lip and palate, Cleft Palate-Craniofacial Journal, 29, 413–418.
Shaw, W. C., Sandy, J. R., Williams, A. C. and Devlin, H. B. (1996 Minimum standards for the management of cleft lip and palate: efforts to close the audit loop, Annals of the Royal College of Surgeons of England, 78, 110–114.[Medline]
Sindet-Pedersen, S. and Enemark, H. (1985 Comparitive study of secondary and late secondary bone-grafting in patients with residual cleft defects. Short-term evaluation, International Journal of Oral Surgery, 14,3 89–398.[Medline]
Williams, A., Shaw, W. C. and Devlin, H. B. (1994)
Provision of services for cleft lip and palate in England and Wales, British Medical
Journal, 309, 1552.
Witsenberg, B. and Freihofer, H. P. M. (1990) Autogenous rib graft for reconstruction of alveolar bone defects in cleft patients, Journal of Cranio-maxillo-facial Surgery, 18, 55–62.
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
