Mandibular Symphyseal Bone Graft for Reconstruction of Alveolar Cleft Defects: Volumetric Assessment With Cone Beam Computed Tomography 1-Year Postsurgery

Analysis of the Complications of Mandibular Cortical Bone with/without Particulate Artificial Bone Graft for Alveolar Cleft Reconstruction: A Retrospective Study

OBJECTIVES

To investigate postoperative complications in patients who underwent alveolar bone graft surgery using mandibular cortical bone (MCB) with/without particulate artificial bone (PAB).

DESIGN

Retrospective study.

SETTING

Department of Oral and Cranio-Maxillofacial Surgery in the hospital from August 2020 to August 2023.

PATIENTS

Patients who underwent alveolar bone graft using MCB were reviewed. They were diagnosed with unilateral or bilateral alveolar cleft, and some of them developed postoperative complications after MCB with/without PAB repair surgery.

INTERVENTIONS

No interventions.

MAIN OUTCOME MEASURE(S)

Complications.

RESULTS

Complications occurred in 12 of 149 patients who underwent surgery (8.05%). Among these evaluated patients, 10 had surgical site infection, 8 had mucosal dehiscence, 2 had discharge of resorbable plate debris, and 6 had grafted bone necrosis. Patients with bilateral alveolar clefts were more likely to experience complications (P = 0.033).

CONCLUSION

MCB with/without PAB grafting is effective enough for patients to undergo reconstruction of the alveolar process.

Three-dimensional comprehensive evaluation of unilateral alveolar cleft bone grafting with iliac bone and chin bone blocks

In this study, we aimed to provide guidance for selecting bone grafting materials in cases of alveolar clefts. Twenty-nine patients with unilateral complete alveolar clefts were categorized into three groups based on the bone grafting material used: Group A (iliac bone block grafts), Group B (iliac cancellous bone grafts), and Group C (chin bone block grafts). Cone-beam computed tomography (CBCT) data were analyzed using Mimics 19.0 software. Results showed that Group A had the highest bone formation rate, with significant differences observed between Groups A and B, as well as between Groups B and C. Group A and Group C had the highest proportion of Type I in volume assessment, while Group B had the highest proportion of Type III, Significant differences were observed in the distribution of volume assessment scores among the three groups. Bone height measurement results indicated that buccal-side measurement points had a higher proportion of Type I bone height than palatal-side measurement points. Bone width measurement results showed that Type I bone width was highest in Group C, while Type IV bone width was highest in Group B. Significant differences were observed in the distribution of implanted bone width among the three groups. Total grafting scores indicated that Types A and D were predominant in Groups A and C, while Group B had the highest proportion of Type D. Significant differences were observed in the distribution of total grafting scores among the three groups. The comprehensive evaluation method provides accurate assessment of alveolar cleft bone grafting outcomes and is applicable in clinical settings. Based on the results, we consider both iliac bone blocks and chin bone blocks as suitable materials for alveolar cleft bone grafting. Grafting material selection should consider preoperative gap volume measured using CBCT, required bone quantity, donor site complications, and overall clinical needs.

Three-dimensional evaluation of secondary alveolar bone grafting in patients with unilateral cleft lip and palate: A 2-3 year post-operative follow-up

OBJECTIVES

The present study aims to quantitatively assess secondary alveolar bone graft (SABG) resorption in unilateral cleft lip, alveolus and palate (UCLAP) patients in a 2-3 year longitudinal follow-up setting by using a validated 3D protocol. Furthermore, the potential relation of SABG resorption with maxillary canine position and a number of patient-related factors was investigated.

METHODS

UCLAP patients who underwent SABG and had good quality CBCT images at the following timepoints were included in the study: pre-operative (T0), immediate (T1), 6 months (T2) and either 1-2 years (T3) or 2-3 years (T4) post-operative. The final bone grafted region was defined on the T1 scans and refined in the registered T0 scans. The bone graft after resorption was determined by applying threshold-based segmentation on the registered T2, T3 or T4 scans within the segmented bone graft volume. The position of the canines was determined at every timepoint at the cleft and non-cleft side.

RESULTS

Forty-five UCLAP patients (mean age 9.0 ± 1.3 years) were included. In the first 6 months after SABG, 43.6% bone resorption was recorded. 2-3 years post-operative, 56% bone resorption was found if the maxillary canine was not yet erupted and 42.7% if it erupted through the graft. The vertical position of the canines was significantly higher on the cleft side at T3.

CONCLUSIONS

The present study reports significant SABG resorption over time. However, no correlation was found between SABG resorption and canine position, nor between other patient-related factors.

Comparison of Alveolar Bone Grafting Outcomes using CBCT in Individuals with UCLP Based on the Presurgical Orthodontic Treatment Methods

OBJECTIVE

The purpose is to evaluate outcomes of alveolar bone grafting based on the pre-grafting orthodontic preparation methods.

DESIGN

Retrospective analysis of individuals with unilateral cleft lip and palate.

SUBJECTS AND SETTINGS

28 individuals with non-syndromic UCLP from two craniofacial centers, 14 individuals each from XXXX and XXXX.

INTERVENTIONS

The alignment group underwent maxillary expansion with incisors alignment while the non-alignment group underwent only maxillary expansion for presurgical orthodontic preparation.

METHODS

Initial and post-surgical CBCT scans were compared to observe changes in angulation of the incisor adjacent to the cleft site, alveolar bony root coverage, and bone graft outcomes.

RESULTS

In the alignment group, the buccolingual rotation decreased by 32.35 degrees (p = .0002), the anteroposterior inclination increased by 14.01 degrees (p = .0004), and the mesiodistal angulation decreased by 17.88 degrees (p = .0001). Alveolar bony coverage did not change after bone graft in both groups, and no difference was observed between the groups. Chelsea scale showed satisfactory bone graft outcome (category A, C) in 12 cases (85.71%) in the alignment group and 11 cases (78.51%) in the non-alignment group. The volumetric measurement showed the alignment group had better bone fill of 69.85% versus 51.45% in the non-alignment group (p = .0495).

CONCLUSIONS

Alveolar bony coverage on the tooth adjacent to cleft sites did not change with alveolar bone grafting surgery in either of the alignment and non-alignment group. Presurgical orthodontic alignment does not induce root exposure nor poorer bone grafting outcome.

Effectiveness of Autogenous Chin Bone Graft in Reconstructive Surgery of Cleft Patients: A Systematic Review With Meta-Analysis and Algorithm of Treatment

PURPOSE

Bone grafting is fundamental in the treatment of cleft patients, and several grafting materials have been used for this purpose. The objective of this study is to evaluate the effectiveness of autogenous bone graft from the chin in the reconstruction of cleft alveolus.

METHODS

Searches were performed in six databases (PubMed, Scopus, Cochrane, LILACS, Embase, and Google Scholar) by two researchers individually until July 2022. This study was registered in the International Prospective Register of Systematic Reviews (CRD42021267954) and conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. The predictor variable is reconstruction technique, grouped into three levels: autogenous genial grafts, other endochondral autogenous grafts, and bio- or tissue-engineered materials. The outcome variables were alveolar cleft healing rate and bone height. The secondary variables were complications that included infections, necrosis, paresthesia, and dehiscence. Data analysis included the risk of bias and assessment of the certainty of evidence by the risk of bias in nonrandomized studies of interventions and grading of recommendations, assessment, development, and evaluation tools, respectively. The meta-analysis was performed with heterogeneity based on random effects of I² and 95% confidence.

RESULTS

In the initial search, 4,833 articles were found, and 10 of them were included in this systematic review. The included studies were from six countries on three different continents, with a sample of 692 patients. It was observed that the chin bone graft (214 patients) when compared to the endochondral bone graft (386 patients) reduced by 0.42 [confidence interval 95% = 0.18, 0.95] times the prevalence of bone resorption (P = .040 and I² = 70%) analyzed in radiographic images. Two studies evaluated the bone filling through computed tomography, and there was no statistically significant difference between the groups (P = .340, I² = 0%). Only two studies had a low risk of bias.

CONCLUSION

Based on a low certainty of evidence, the chin autogenous bone graft proved to be similar to the endochondral graft in the reconstruction of the cleft alveolar; however, the limited number of studies with high heterogeneity and an uncertain risk of bias decreased the strength of the results found in this systematic review. New controlled primary studies should be carried out with the purpose of safely determining the effectiveness of chin bone grafts for the reconstruction of cleft alveolar.

Clinical Application of Allograft Bone of Alveolar Cleft Repair

OBJECTIVES

To investigate the osteogenic effect of allograft bone (BIO-GENE) and autologous iliac crest bone graft in the alveolar cleft repair.

MATERIALS AND METHODS

A total of 131 patients with congenital unilateral alveolar cleft who consulted in our hospital from January 2016 to May 2021 were selected and divided into 3 groups according to the different bone restoration materials used. Group A totaling 43 cases was the autologous bone group; group B totaling 41 cases was the BIO-GENE group; and group C totaling 47 cases was the BMP-2+BIO-GENE group. The preoperative and postoperative cone beam CT data of the same patient were imported into MIMICS 21.0 in DICOM format. The preoperative cleft volume and newly formed bone volume were calculated by 3-dimensional reconstruction to measure their osteogenic rate.

RESULTS

The differences in osteogenesis rates were not statistically significant in the group B compared with the group A, and in the group C compared with the group B ( P >0.05 for both). The differences in osteogenesis rates were statistically significant in the group C compared with the group A ( P =0.003).

CONCLUSIONS

Comparative studies found the allograft bone with an ideal artificial material to repair alveolar clefts has become possible. Meanwhile, the addition of BMP-2 in the allograft bone significantly increased the osteogenic rate.

Cleft Size and Success of Secondary Alveolar Bone Grafting-A Systematic Review

OBJECTIVE

This study aimed to review all research evidence of presurgical cleft size and related factors to success of secondary alveolar bone grafting (SABG).

DESIGN AND SETTING

The systematic review searched the OVID-Medline®, PubMed®, Embase®, and Cochrane Central Register of Controlled Trials (CENTRAL) up to August 2020. Two reviewers independently selected potential abstracts for full review. Disagreeements were resolved by consensus. The first author extracted data and assessed the risk of bias using Risk of Bias in Non-randomized studies-of Interventions tool.

PATIENTS AND INTERVENTIONS

Patients with non-syndromic clefts who received SABG were selected. Presurgical cleft size/volume and treatment results must be available.

MAIN OUTCOME MEASURES

Level of the grafted bone, achievement of orthodontic tooth movement into the grafted area, need for re-operation.

RESULTS

From 962 abstracts, 23 publications were included. Mean cleft width was 6.80 ± 1.98 mm, cleft area 20-240 mm², and mean volume 0.89 ± 0.33 cm³. No definite conclusion was achieved on whether a narrow or wide cleft showed better treatment outcomes, but other potentially related factors were good oral hygiene and eruptive force of the maxillary canines. Lack of a standard definition of cleft size, a small sample size, varying outcome parameters, and moderate-to-high risk of bias contributed to the summary. A meta-analysis could not be performed because of the heterogeneity.

CONCLUSION

Due to insufficient evidence, cleft width/volume could not be specified leading to more successful SABG. Care of patients could be improved in both research by following rigorous methodology, and practice by clear communication.

Machine learning in 3D auto-filling alveolar cleft of CT images to assess the influence of alveolar bone grafting on the development of maxilla

BACKGROUND

Machine learning based auto-segmentation of 3D images has been developed rapidly in recent years. However, the application of this new method in the research of patients with unilateral cleft lip and palate (UCLP) is very limited. In this study, a machine learning algorithm utilizing 3D U-net was used to automatically segment the maxilla, fill the cleft and evaluate the alveolar bone graft in UCLP patients. Cleft related factors and the surgery impact on the development of maxilla were analyzed.

METHODS

Preoperative and postoperative computed tomography images of 32 patients (64 images) were obtained. The deep-learning-based protocol was used to segment the maxilla and defect, followed by manual refinement. Paired t-tests and Mann-Whitney tests were performed to reveal the changes of the maxilla after surgery. Two-factor, two-level analysis for repeated measurement was used to examine the different trends of growth on the cleft and non-cleft sides of the maxilla. Pearson and Spearman correlations were used to explore the relationship between the defect and the changes of the maxillary cleft side.

RESULTS

One-year after the alveolar bone grafting surgery, different growth amount was found on the cleft and non-cleft sides of maxilla. The maxillary length (from 34.64 ± 2.48 to 35.67 ± 2.45 mm) and the alveolar length (from 36.58 ± 3.21 to 37.63 ± 2.94 mm) increased significantly only on the cleft side while the maxillary anterior width (from 11.61 ± 1.61 to 12.01 ± 1.41 mm) and posterior width (from 29.63 ± 2.25 to 30.74 ± 2.63 mm) increased significantly only on the non-cleft side after surgery. Morphology of the cleft was found to be related to the pre-surgical maxillary dimension on the cleft side, while its correlation with the change of the maxilla after surgery was low or not statistically significant.

CONCLUSION

The auto-segmentation of the maxilla and the cleft could be performed very efficiently and accurately with the machine learning method. Asymmetric growth was found on the cleft and non-cleft sides of the maxilla after alveolar bone graft in UCLP patients. The morphology of the cleft mainly contributed to the pre-operation variance of the maxilla but had little impact on the maxilla growth after surgery.

Three-dimensional Assessment of Autologous Calvarial Bone Grafting for Alveolar Clefts Reconstruction in Pediatric Population: A Retrospective Study

Reconstruction of alveolar clefts using cancellous bone graft is associated with a high rate of resorption. The aim of this study was to evaluate the osseointegration capacity of cortical calvarial bone grafting using 3-dimensional imaging assessment for alveolar cleft reconstruction in pediatric population.All alveolar bone grafting procedures performed between January 2015 and October 2017 in the maxillofacial surgery department of Lille University Hospital were included. All patients were evaluated clinically and by 3-dimensional imaging before bone grafting and at 3 months after surgery. Cleft and bone graft volumes were assessed using Horos software, v. 3.3.5, through a segmentation process. The bone filled ratio at 3 months after surgery was calculated. A total of 48 alveolar bone grafting procedures were performed in 37 patients: 3 unilateral cleft lip and alveolar, 20 unilateral cleft lip and palate, and 25 bilateral full cleft lip and palate (3 patients had only unilateral surgery). The mean bone filled ratio was 72.27%±23.65%, 81% for unilateral cleft lip and alveolus, 75.4%±20.6 for unilateral cleft lip and palate, and 65.5%±30 for bilateral complete cleft lip and palate ( P =0.1981). Calvarial bone grafting seems to be a relevant alternative to other donor sites for alveolar cleft reconstruction.

Correlation between alveolar cleft morphology and the outcome of secondary alveolar bone grafting for unilateral cleft lip and palate

Background

Secondary alveolar bone grafting (SABG) is an integral part of the treatment for cleft lip and alveolus and cleft lip and palate. However, the outcome of SABG was not satisfactory as expected, factors that affecting the outcome were still controversial. The aims of this study were to summarize a new method for the classification of alveolar cleft morphology in patients with unilateral cleft lip and alveolus or unilateral cleft lip and palate, to evaluate the correlation between the morphology and SABG outcomes, to identify factors that might predict the outcomes.

Methods

The characteristics of the cleft morphologies of 120 patients who underwent SABG were observed using the preoperative Cone-Beam Computed Tomography (CBCT) images. 52 patients who had CBCT scans performed at least 6 months after SABG were included for the evaluation of outcomes. Both categorical and continuous evaluation methods were measured. Correlations between cleft morphology and SABG outcomes were assessed using the Pearson correlation coefficient in SPSS 27.0.0.

Results

A new method for the classification of cleft morphology was summarized:type I, prism type (labial defect size ≥ palatal defect size; nasal defect size ≥ occlusal defect size); type II, prism’ type (labial defect ≥ palatal defect; nasal defect < occlusal defect); type III, inverted prism type (palatal defect ≥ labial defect); type IV, funnel type (presented as a significantly narrow defect area in the middle towards the vertical dimension); and type V, undefinable (extremely irregular morphology can’t be defined as any of the above types). Categorical evaluation showed 8 failure, 11 poor, 12 moderate, and 21 good results, while the average bone filling rate was 59.24 ± 30.68%. There was a significant correlation between the cleft morphology and categorical/continuous evaluation outcome (p < 0.05).

Conclusion

The new method for the classification of alveolar cleft morphology summarized in this study was comprehensive and convenient for clinical application. Both categorical and continuous methods should be used for radiographic assessments in patients undergoing SABG. The chances of a successful procedure might be better when the patient has type I or IV morphology, in which the shape is like a funnel in the relatively palatal or occlusal area towards the vertical dimension. A relatively great amount of bone resorption was observed in most patients.

Trial registration Chinese clinical trial registry; registration number: ChiCTR2100054438.

Three-dimensional finite element analysis of the effect of alveolar cleft bone graft on the maxillofacial biomechanical stabilities of unilateral complete cleft lip and palate

BACKGROUND

The objective is to clarify the effect of alveolar cleft bone graft on maxillofacial biomechanical stabilities, the key areas when bone grafting and in which should be supplemented with bone graft once bone resorption occurred in UCCLP (unilateral complete cleft lip and palate).

METHODS

Maxillofacial CAD (computer aided design) models of non-bone graft and full maxilla cleft, full alveolar cleft bone graft, bone graft in other sites of the alveolar cleft were acquired by processing the UCCLP maxillofacial CT data in three-dimensional modeling software. The maxillofacial bone EQV (equivalent) stresses and bone suture EQV strains under occlusal states were obtained in the finite element analysis software.

RESULTS

Under corresponding occlusal states, the EQV stresses of maxilla, pterygoid process of sphenoid bone on the corresponding side and anterior alveolar arch on the non-cleft side were higher than other maxillofacial bones, the EQV strains of nasomaxillary, zygomaticomaxillary and pterygomaxillary suture on the corresponding side were higher than other maxillofacial bone sutures. The mean EQV strains of nasal raphe, the maximum EQV stresses of posterior alveolar arch on the non-cleft side, the mean and maximum EQV strains of nasomaxillary suture on the non-cleft side in full alveolar cleft bone graft model were all significantly lower than those in non-bone graft model. The mean EQV stresses of bilateral anterior alveolar arches, the maximum EQV stresses of maxilla and its alveolar arch on the cleft side in the model with bone graft in lower 1/3 of the alveolar cleft were significantly higher than those in full alveolar cleft bone graft model.

CONCLUSIONS

For UCCLP, bilateral maxillae, pterygoid processes of sphenoid bones and bilateral nasomaxillary, zygomaticomaxillary, pterygomaxillary sutures, anterior alveolar arch on the non-cleft side are the main occlusal load-bearing structures before and after alveolar cleft bone graft. Alveolar cleft bone graft mainly affects biomechanical stabilities of nasal raphe and posterior alveolar arch, nasomaxillary suture on the non-cleft side. The areas near nasal floor and in the middle of the alveolar cleft are the key sites when bone grafting, and should be supplemented with bone graft when the bone resorbed in these areas.

Predictive factors for secondary alveolar bone graft failure in patients with cleft alveolus

OBJECTIVE

This single-centre retrospective cohort study aimed to evaluate secondary alveolar bone grafting (SABG) and identify the factors associated with failure.

METHODS

Individuals born with alveolar cleft with or without cleft palate who had SABG consecutively between 2004-2006 and 2011-2013 were enrolled in this study. After the exclusion of 20 cases due to poor quality radiographs, 115 patients (50 girls and 65 boys) who had undergone 131 SABG procedures were included. According to a modification of the Bergland Scale (mBS), the alveolar bone level was assessed using occlusal films obtained 3 months after SABG. Data on factors plausible for SABG failure were collected from patient records, photographs, cast models, and presurgical occlusal radiographs. The Mantel Haenszel Chi-Square test was used to test the possible impact of these factors on the mBS scores.

RESULTS

A total failure (mBS score of 4) was observed in 9% of the cases. The alveolar bone level correlated with cleft laterality (P = 0.039), alveolar cleft extension (P = 0.033), age at SABG (P = 0.007), root developmental stage (P = 0.021), and oral hygiene (P = 0.007).

CONCLUSION

Secondary alveolar bone grafting failure was correlated with a bilateral alveolar cleft, absence of an initial partial alveolar bridge, higher age, increased root developmental stage, and poor oral hygiene. Efforts to achieve optimal oral hygiene are recommended to improve outcomes, particularly when SABG is performed in individuals with a bilateral cleft, increased alveolar cleft extension, or at higher ages.

Validation of a 3D methodology for the evaluation and follow-up of secondary alveolar bone grafting in unilateral cleft lip and palate patients

OBJECTIVE

The aim of the study was to propose and validate a method for three-dimensional (3D) quantitative assessment of secondary alveolar bone grafting (SABG) and its stability in time for patients with unilateral cleft lip and palate (UCLP).

SETTINGS AND SAMPLE POPULATION

Ten non-syndromic UCLP patients (9 males and 1 female with a mean age of 9.5 ± 0.9 years) undergoing SABG with good quality preoperative, immediate postoperative (6 weeks) and 6 months postoperative Cone Beam Computed Tomography (CBCT) scans were selected.

MATERIALS AND METHODS

The preoperative and 6 months postoperative scans were registered onto the immediate postoperative scan. The bone-grafted region was defined on the immediate postoperative scan and refined on the registered preoperative scan resulting in a 3D volume. The residual bone graft was calculated by applying threshold based segmentation on the registered 6 months postoperative scan within the segmented bone graft volume of the previous step. Inter and intra observer tests using intra-class correlation coefficient (ICC) were applied comparing the volumes of the 3D models.

RESULTS

An excellent reliability was found for inter and intra observers with ICC ≥ 0.95.

CONCLUSIONS

The presented method proved to be reliable for volumetric assessment of the alveolar bone graft in UCLP patients, as well as to assess the percentage of bone resorption during follow-up.

Alveolar bone heights of maxillary central incisors in unilateral cleft lip and palate patients using cone-beam computed tomography evaluation

PURPOSE

The aims of this retrospective cross-sectional study were to measure and compare labial and palatal alveolar bone heights of maxillary central incisors in unilateral cleft lip and palate patients, following STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) guidelines.

PATIENTS AND METHODS

The study group consisted of 21 patients with a mean age of 16 years. High-resolution cone-beam computed tomography was performed at least one year after secondary alveolar bone grafting. The experimental side was the cleft side and the contralateral side without congenital cleft was the control. Measurements were performed on incisors' midsagittal cross-sections. The Wilcoxon signed-rank test was used for intergroup comparisons.

RESULTS

The labial and palatal distances between alveolar bone crests and cementoenamel junctions were significantly greater on the cleft side than on the noncleft side. Mean differences were 0.75 and 1.41 mm, respectively. The prevalence of dehiscences at the cleft side maxillary central incisors was 52% on the labial surface and 43% on the palatal surface. In the controls, it was 19% and 14%, respectively.

CONCLUSION

The cleft-adjacent maxillary central incisors had more apically displaced alveolar bone crests on the labial and palatal sides of the roots than the controls. Higher prevalence of dehiscences was found on the cleft side. Bone margin differences predispose to gingival height differences of the central incisors. These differences could increase the demands of patients to obtain more esthetic treatment results with orthodontic extrusion and periodontal intervention on the cleft side.

A novel method for alveolar bone grafting assessment in cleft lip and palate patients: cone-beam computed tomography evaluation

Objectives

This retrospective cross-sectional study aimed to present a new method for secondary alveolar bone grafting (SABG) assessment and to qualitatively evaluate the SABG results in unilateral cleft lip and palate patients.

Materials and methods

Research was conducted according to the STROBE guidelines. The study group consisted of 21 patients with a mean age of 16 years. High-resolution cone-beam computed tomography (CBCT) was performed at least 1 year after grafting. The experimental side was the cleft side, and the contralateral side without a congenital cleft was the control. Measurements were performed at four levels of the maxillary central incisors’ roots according to the new scale with scores from 0 to 3. The sum of the scores provided a general assessment of bone architecture. The Wilcoxon signed-rank test was used for intergroup comparisons, and a Kappa coefficient was used for reproducibility measurements.

Results

High individual variability was found, and the bone architecture was significantly worse on the cleft side than on the noncleft side. The results showed 28.57% failure, 33.33% poor, 19.05% moderate, and 19.05% good results from the surgical procedure. Kappa coefficients produced results from 0.92 to 1.00 for intra-rater and from 0.81 to 1.00 for inter-rater reproducibility.

Conclusions

CBCT provides detailed information about alveolar bone morphology. The new assessment method is useful at every treatment stage and provides excellent repeatability. SABG did not provide good bone morphology, in most cases.

Clinical relevance

This research presents a new universal alternative for the assessment of SABG by utilizing CBCT.

Electronic supplementary material

The online version of this article (10.1007/s00784-020-03505-z) contains supplementary material, which is available to authorized users.

Effectiveness of corticocancellous bone graft in cleft lip and palate patients: A systematic review

OBJECTIVE

Both cancellous bone graft and corticocancellous bone graft are the most common grafts for repairing alveolar cleft, but there is no clear conclusion as to which method is beneficial to repair the alveolar cleft. The aim was to determine the effectiveness of corticocancellous bone graft in cleft lip and palate patients.

MATERIALS AND METHODS

Electronic databases including PubMed, Ovid, Embase, Cochrane Library, Web of Knowledge, and China Biology Medicine disc (SinoMed) were searched. Only studies published in English or Chinese were included. The last search was updated on 1 January 2020. 2638 articles remaining after the exclusion of duplicates. Finally, there were 16 publications (15 in English and 3 in Chinese) eligible for systematic review according to the previously established inclusion and exclusion criteria. A descriptive statistical method was used to present data. The methodological index for non-randomized studies (MINORS) was used to determine the risk of bias.

RESULT

Sixteen articles were included in this review, of which 15 publications were retrospective study and one was a comparative study. The average success rate of reconstruction with block bone was approximately 90.8%, while the success rate of the cancellous bone graft was about 85.3%. The incidence of wound dehiscence was approximately 10% to 16%, and infection is about 9% to 20%. The incidence of oronasal fistula resulting from severe bone resorption and infection was approximately 7.5% to 10.5%.

CONCLUSION

There is a higher bone formation rate of corticocancellous bone graft in patients with the alveolar cleft. However, more studies with high methodological quality and with a longer follow-up are needed to offer more safety for practitioners and patients regarding the surgical method selected to repair the cleft alveolar.

Current methods for secondary alveolar bone grafting assessment in cleft lip and palate patients - A systematic review

INTRODUCTION

The development of 3D X-ray diagnostics has led to new methods for secondary alveolar bone grafting (SABG) assessment. The aim of this study was to collect and present literature from the years 2007-2018, and review on the current treatment outcome assessment methods for SABG.

MATERIALS AND METHODS

A systematic review of literature from 2007 to 2018 was carried out, following PRISMA guidelines. 426 records were identified after duplicate references had been removed. 25 articles were included in the review. The Cochrane Collaboration tool or the methodological index for non-randomized studies was used for quality evaluation.

RESULTS

Computed tomography and cone beam computed tomography were preferentially used for SABG treatment outcome verification. There were different assessment protocols. Due to the ways in which results were presented, methods were divided into five groups: linear measurements, volumetric measurements, density measurements, percentage ratios, and scales. There was only one randomized, controlled trial with high methodological quality.

CONCLUSIONS

1. Currently, 3D X-ray imaging is a standard treatment outcome verification method for SABG. 2. It is necessary to establish the required postoperative follow-up time for best SABG treatment outcome assessment. More prospective studies to assess bone graft outcomes after 6 months and 1 year are required.

Three-dimensional radiological evaluation of secondary alveolar bone grafting in cleft lip and palate patients: a systematic review

OBJECTIVES

To systematically review the existing literature on the three-dimensional (3D) radiological evaluation of secondary alveolar bone grafting (SABG) in cleft lip and palate (CLP) patients, with specific interest in 3D imaging protocols and assessment methods.

METHODS

A comprehensive literature search on PubMed, Embase and the Cochrane Library was conducted. Included publications concerned 3D imaging for evaluation of SABG in CLP patients while articles about primary or tertiary bone grafting or using of two-dimensional images only were excluded. Study quality was evaluated using the Methodological Index for Non-Randomized Studies  or the Cochrane Collaboration tool for assessing risk of bias.

RESULTS

The search yielded 1735 citations, of which 38 met the inclusion criteria. We noticed a large variability in imaging protocols and bone graft evaluation methods between studies. Most articles were observational studies with medium to low methodological quality, except for the one randomised clinical trial having a low risk of bias.

CONCLUSIONS

There is a lack of prospective, controlled trials based on a consistent imaging protocol with a sufficiently long follow-up period. A pressing need exists for the development of a consistent optimized imaging protocol for diagnosis and follow up of SABG in CLP patients. Although 3D evaluation methods seem to be more precise than two-dimensional methods, we should be careful when comparing the outcomes arising from different 3D measuring techniques.

Three-dimensional imaging methods to quantify soft and hard tissues change after cleft-related treatment during growth in patients with cleft lip and/or cleft palate: a systematic review

OBJECTIVES:

To assess the use of three-dimensional (3D) imaging methods to quantify the changes in soft- and hard-tissues in cleft patients after cleft-related treatment during growth.

METHODS:

PubMed, EMBASE, Web of Science and the Cochrane Library were searched up to 1 June 2018. Included publications were those using 3D imaging to quantify soft- and hard-tissue changes after cleft-related treatments in patients with any type of cleft, during growth. Data extraction and qualitative analysis were performed by two reviewers. The methodological quality of each study was reviewed using the QUADAS-2 tool.

RESULTS:

From 4 databases, 2315 articles were found. Full texts of 422 articles were analyzed and finally 12 articles were included for qualitative analysis. CT was performed in the majority of studies for hard-tissue quantification. Stereophotogrammetry, Laser scanner and 3D digitizer were identified as viable methods to quantify both soft- and hard-tissue changes, depending on whether the scan was made of the facial surface or the cast surface. Most studies conducted imaging analysis without registration between multitemporal images, which is the reason why they did not fulfil the inclusion criteria.

CONCLUSIONS:

Although several imaging modalities have the potential to quantify cleft-related treatment follow-up, there is an urgent need to assess the imaging methods and related analyses allowing to standardise a 3D imaging protocol to quantify hard- and soft-tissue treatment follow-up.

Volumetric comparison of autogenous bone and tissue-engineered bone replacement materials in alveolar cleft repair: a systematic review and meta-analysis

The goal of reconstruction of the alveolar cleft in patients with cleft lip and palate is to improve the quality of tissue, the structural stability, and increase the volume of bone. This study is a systematic review with meta-analysis of volumetric bony filling using autogenous bone and various tissue-engineered bone substitutes. We made an electronic search on MEDLINE, EMBASE, SCOPUS, WEB OF SCIENCE, "grey" publications (materials and research produced by organisations outside traditional channels for commercial or academic publishing and distribution), and relevant cross references according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies that reported the outcomes of volumetric grafting were included in the meta-analysis. Of 1276 studies, 26 were included in the meta-analysis. Pooled analysis of 25 studies that used autogenous bone showed a significant reduction in the volume of the cleft equivalent to 62.0% bone fill (95% CI 54.3 to 69.6), in contrast to 10 studies that used a tissue-engineered material and reported bone filling of 68.7% (95% CI 54.5 to 82.8). The estimated sizes of pooled effects across studies showed that there was no significant difference between the two major intervention groups (p value 0.901). Our statistical analysis showed that autogenous bone grafts did not differ significantly from tissue-engineered materials in their ability to fill clefts. Systematic review registration: International Prospective Register of Systematic Reviews, PROSPERO (CRD42017065045).

An Analysis of Mandibular Symphyseal Graft Sufficiency for Alveolar Cleft Bone Grafting

The purpose of this study was to evaluate the sufficiency of the mandibular symphysis as a donor site for unilateral and bilateral alveolar grafting, measuring both the alveolar cleft volume and maximum bone graft volume that can be harvested from the mandibular symphysis using 3-dimensional computed tomography (CT) and software in children and adults. Computed tomography data obtained from 20 unilateral and bilateral cleft lip palates patients in the preoperative period were used in this study. The patients were divided into 2 groups: children (female, n = 5; male, n = 5) and adults (female, n = 5; male, n = 5). The required bone graft volume for grafting and the maximum bone graft volume that can be harvested from the mandibular symphysis were measured based on cone beam CT data and software. The average required bone graft volume (cleft volume) for unilateral alveolar grafting was 963.51 ± 172.31 mm in the children and 1001.21 ± 268.16 mm in the adults. The average required bone graft volume for bilateral alveolar grafting was 1457.82 ± 148.18 mm in the children and 2189.59 ± 600.97 mm in the adults. The average the mandibular symphysis bone graft volume was 819.29 ± 330.85 mm in the children and 2164.9 ± 1095.86 mm in the adults. The results demonstrated that the mandibular symphysis region provided an adequate bone volume for alveolar grafting in adults with unilateral alveolar clefts. However, it is difficult to standardize these results, due to cleft volume and graft volume that could be harvested from the mandibular symphysis are highly variable among individuals.

A new method of volumetric assessment of alveolar bone grafting for cleft patients using cone beam computed tomography

OBJECTIVE

The aims of this study were to propose a new method for volumetric assessment of alveolar bone grafting and to quantitatively assess alveolar bone grafting based on this method.

STUDY DESIGN

Cone beam computed tomography images of 18 patients with unilateral cleft alveolus were selected. Volume of the alveolar cleft before grafting operation (VOLcleft), graft bone filled into cleft immediately after operation (VOLgraft), and bony bridge formed 1 year after operation (VOLbridge) were obtained. The grafting fill rate (VOLgraft/VOLcleft × 100%), bony bridge formation rate (VOLbridge/VOLcleft × 100%), and grafting resorption rate [(VOLgraft - VOLbridge)/VOLgraft × 100%] were calculated. Correlations between these parameters were investigated. Intraobserver and interobserver reliability of this method was assessed.

RESULTS

Intraobserver and interobserver reliability was good as no statistically significant difference was seen, and the Pearson correlation coefficient was significant (intraobserver R ≥ .953; interobserver, R ≥ .859). A positive linear correlation (R² = .808; P < .001) between grafting fill rate and bony bridge formation rate and a negative linear correlation (R² = .458, P = .002) between grafting fill rate and grafting resorption rate were found.

CONCLUSIONS

This method was practical and valuable for quantitative assessment of alveolar bone grafting.