Secondary alveolar bone grafting is typically performed between the ages of 7-12 years before the eruption of the permanent canine. Studies have been conducted on a both autologous and alloplastic bone sources with ongoing discussions over preferred donor sites. Since 2007, the recombinant human bone morphogenetic protein-2 (rhBMP-2) has been available as an alternative to autologous bone graft for localized alveolar ridge augmentation.
The aim of this review was to compare the effectiveness of autologous versus alloplastic bone for secondary alveolar bone grafting in patients with cleft lip and palate.
Searches were conducted in the Cochrane Oral Health Group’s Trials Register, Cochrane Central Register of Controlled Trials, Medline, Embase, Chinese Biomedical Literature Database and WHO International Clinical Trials Registry Platform databases. Randomised controlled trials (RCTs) in patients with unilateral cleft lip and palate older than 5 years of age, radiographic evaluation (CT and/or CBCT) of the cleft area, with at least a 6-month follow-up following bone grafting were considered.
The primary outcomes were radiographic assessment of bone graft volume and the radiographic assessment in the grafted area of alveolar bone. Length of hospital stay was a secondary outcome. Two reviewers independently selected studies, abstracted data and assessed risk of bias using the Cochrane tool. A random effects meta-analysis was carried out. The overall quality of evidence was assessed using the grading of recommendation, assessment, development, and evaluation (GRADE) instrument.
- 4 RCTs involving a total of 57 patients were included.
- 27 patients received a rhBMP-2 graft and 29 an iliac crest bone graft.
- 2 studies were carried out in Brazil, 1 in Sweden and 1 in the USA.
- 2 studies were considered to be at high risk of bias and 2 at unclear risk.
- Bone graft volume
- At 6 months a statistically significant difference in favour of autologous bone graft was found
- Mean Difference (MD) = − 14.410 (95% CI; − 22.392 to − 6.428) [ 3 studies].
- At 12 months no difference was noted; MD = 6.227 (95%CI; − 15.967 to 28.422) [ 3 studies].
- Bone graft height
- No statistical difference was noted at 6 months MD = − 18.737 (95%CI; − 43.560 to 6.087) [ 2 studies].
- Similarly, there was no difference at 12 months MD = −4.401 (95%CI; −30.636 to 21.834) [ 3 studies].
- Length of hospital stay
- This was assessed in 2 studies with patients undergoing rhBMP-2 graft having a statistically significant shorter stay, MD= − 1.146 (95%CI; − 2.147 to − 0.145).
- The overall quality of the evidence was rated as low.
The authors concluded: –
Autologous bone and rh-BMP2 graft showed a similar effectiveness in maxillary alveolar reconstruction in patients with unilateral cleft lip and palate assessing bone graft volume and height although rh-BMP2 graft showed a relative shorter length of hospital stay (high uncertainty level).
A previous Cochrane review (Guo et al 2011) has examined secondary bone grafting for alveolar clefts. At that time only 2 RCT were included 1 of which was included in the current review. The Cochrane review concluded;
Due to the high level of risk of bias in the two included trials there is insufficient evidence to conclude that one intervention is superior to another.
This new review included 4 small RCTs none of which were at low risk of bias. The low methodological quality of the studies is a key limitation to the review as highlighted by the reviewers. So, while the findings suggest that there is no apparent difference between the two techniques the results should be interpreted cautiously. Further well conducted and reported trials of appropriate size are required to clarify which of these two approaches is most effective.
Scalzone A, Flores-Mir C, Carozza D, d’Apuzzo F, Grassia V, Perillo L. Secondary alveolar bone grafting using autologous versus alloplastic material in the treatment of cleft lip and palate patients: systematic review and meta-analysis. Prog Orthod. 2019 Feb 11;20(1):6. doi: 10.1186/s40510-018-0252-y. Review. PubMed PMID: 30740615; PubMed Central PMCID: PMC6369233.
Guo J, Li C, Zhang Q, Wu G, Deacon SA, Chen J, Hu H, Zou S, Ye Q. Secondary bone grafting for alveolar cleft in children with cleft lip or cleft lip and palate. Cochrane Database Syst Rev. 2011 Jun 15;(6):CD008050. doi:10.1002/14651858.CD008050.pub2. Review. PubMed PMID: 21678372.