Assessment of Bone Resorption after Secondary Alveolar Bone Grafting Using Three-Dimensional Computed Tomography: A Three-Year Study

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.

Evaluation of Secondary Alveolar Bone Grafting for Unilateral Complete Cleft Alveolus: A Retrospective Cone Beam Computed Tomography-Based Study

Background: In patients with cleft lip and palate (CLP), secondary alveolar bone grafting (SABG) with particulate cancellous bone marrow (PCBM) is recommended. Objective: To compare bone graft outcomes in patients with unilateral CLP, when SABG is completed before or after canine tooth eruption (ACE or BCE), as measured by cone beam computed tomography (CBCT). Methods: Patients were allocated into two cohorts, ACE and BCE. The outcomes were evaluated using CBCT, followed by univariate and multifactorial analyses. Results: A total of 468 patients (age 11.61 ± 4.03 years; male/female 288/180) were analyzed, including 282 in the BCE group (9.41 ± 1.59 years, 175/107) and 186 in the ACE group (14.95 ± 4.31 years, 113/73). Although 5-level assessment revealed no significant difference in clinical success rate (>4 points) between the BCE and ACE groups (53.90% vs. 47.85%, p = 0.20), BCE group showed significantly higher rate of bone bridges formation (73.05% vs. 62.90%, p = 0.02), which can be attributed to variations in orthodontic participation and follow-up time. Independent predictors of graft failure were wide cleft, severe oronasal fistula, no palatal bone wall, and insufficient PCBM filling (p < 0.01). Conclusions: SABG should be performed before canine eruption with more aggressive PCBM filling and oral fistula management.

Three-dimensional nasal asymmetry analysis between adolescence and adulthood in postoperative patients with unilateral cleft lip and palate using computed tomography

AIM

To investigate the differences of the nasal soft and hard tissue asymmetry in postoperative patients with unilateral cleft lip and palate (UCLP) between adolescence and adulthood, and to explore the correlation of nasal soft and hard tissue asymmetry.

METHODS

CT data from 47 repaired UCLP patients were included and divided into two groups:1. adolescent group: 23 patients (15 males, 8 females; age: 10-12 years old). 2. adult group: 24 patients (16 males, 8 females; age:18-32 years old). The three-dimensional asymmetry in nasal soft and hard tissues was analyzed. Additionally, the correlation between nasal soft and hard tissue asymmetry was also analyzed.

RESULTS

Both the adolescent group and adult group showed asymmetries in nasal soft and hard tissues. Compared to the adolescent group, the adult group had a significantly increased horizontal asymmetry of nasal soft tissues Sbal (P < 0.05). Furthermore, the sagittal asymmetry of soft tissue Glat (P < 0.05), Sbal (P < 0.001), Sni (P < 0.001) and hard tissue LPA (P < 0.05) also increased significantly. In the adult group, there were more landmarks with a correlation between the asymmetry of nasal hard tissue and soft tissue compared to the adolescent group. There were moderate to strong correlations between nasal hard and soft tissue symmetries in the horizontal and sagittal directions (0.444 < r < 764), but no correlation in the vertical direction in the adult group (P > 0.05).

CONCLUSIONS

The asymmetry of nasal soft and hard tissues in patients with repaired UCLP becomes more apparent in the horizontal and sagittal dimensions from adolescence to adulthood. The correlation between the asymmetry of nasal hard tissue and soft tissue becomes stronger in the horizontal and sagittal dimensions. These factors should be taken into account when performing treatment for repaired UCLP patients in adolescence and adulthood.

Postoperative Radiologic Imaging in Secondary Alveolar Bone Grafting for Cleft Lip and Palate: A Systematic Review and Meta-Analysis

INTRODUCTION

Radiographs (XRs), computed tomography (CT) scans, and cone-beam CT (CBCT) scans are utilized for assessment of secondary alveolar bone graft (SABG) in patients with cleft lip and palate (CLP). However, the optimal choice for imaging modality remains unclear. This study compares the image fidelity and safety profile for XR, CT, and CBCT in the assessment of patients with CLP who have undergone SABG.

METHODS

Articles from MEDLINE and Elsevier Embase were screened. The primary outcome was graft success rate. Secondary outcomes were percent-by-volume of graft maintained and patient safety, defined by radiation exposure. A random effects model was used to calculate the pooled outcomes for each imaging modality. Chi-squared analysis was used to compare pooled outcomes between different imaging modalities.

RESULTS

Of the 149 articles identified initially, 14 were included. Computed tomography exhibited a significantly higher image fidelity demonstrated by a lower graft success rate (62.0%) compared with both XR (72.6%, P<0.01) and CBCT (69.8%, P<0.01). Cone-beam CT had the lowest reported percent-by-volume of graft maintained (32.1%). Computed tomography had a higher mean radiation dosage (39.7 milligray) than what has been reported for both XR and CBCT.

CONCLUSION

Computed tomography demonstrated lower graft success rates than both XR and CBCT, possibly indicating a higher image fidelity. However, compared with CBCT, CT may have a higher radiation exposure. Randomized trials and longitudinal studies are necessary to perform a direct comparison between CT and CBCT and to correlate the image fidelity of these modalities with clinical outcomes.

Bioglass 45S5, a relevant alternative to autogenous harvesting for secondary alveolar bone grafts in clefts? Retrospective study of one hundred surgeries

The secondary alveolar bone grafting (SABG) step restores the continuity of the alveolar bone necessary for dentition. Faced with the complications of autografts, synthetic biomaterials such as Bioglass (BG) 45S5 have been proposed. The objective was to evaluate the success rate of SABG with the addition of BG 45S5 and to highlight the prognostic factors. Patients who underwent operation between 2015 and 2021 and had follow-up cone-beam computed tomography (CBCT) were analyzed. Multivariate analysis was performed to determine factors influencing radiographic success. A total of 102 SABG were analyzed. They were unilateral total cleft lip and palate (49, 48.0%). The mean age at surgery was 9.32 ± 3.09 years. Surgeries were performed mainly outside a syndromic context and without a family history after orthodontic preparation. The radiographic success rate at 1 year was 80.4%. Mixed dentition stage (odds ratio [OR] = 7.3, p = 0.024), absence of syndromic context (OR = 20.7, p = 0.024) and female sex (OR = 4.88, p = 0.021) were factors predictive of surgical success. The use of BG 45S5 instead of autograft is relevant for SABG, with a 1-year success rate of over 80%. The stage of mixed dentition, the absence of syndromic context, and female sex were factors for good prognosis.

The impact of immediate versus delayed mini-screw placement on alveolar bone preservation and bone density following tooth extraction: evidence from a canine model

The aim of this study was to evaluate the impact of mini-screw placement on the alveolar ridge using a split-mouth design. Twelve beagles underwent bilateral extraction of their lateral teeth. In the immediate group, a mini-screw was unilaterally placed approximately 3-4 mm below the alveolar crest of the extraction site on the experimental side. The delayed group received mini-screws six weeks after tooth extraction. On average, the dogs were sacrificed after 11 weeks, and the maxillary bones were excised and scanned using cone-beam computed tomography (CBCT). Histopathological examinations were conducted to assess inflammation and bone formation scores. The results showed that in the immediate group, bone height was significantly greater on the intervention side compared to the control side (p < 0.05), whereas there was no significant difference in the delayed group. In both groups, there was a significant increase in bone density around the mini-screws compared to the control sides (p < 0.05). Mini-screw insertion led to a significant enhancement of bone growth in both groups (p < 0.05), with no notable differences between the two groups. The mini-screws did not have any impact on bone inflammation or width. Overall, both immediate and delayed mini-screw placement in the extraction socket positively influenced bone dimensions, density, and histological properties. However, immediate insertion was more effective than delayed placement in preserving vertical bone height, despite delayed insertion resulting in higher bone density.

Differences in Practice in Alveolar Bone Grafting Among American Cleft Palate-Craniofacial Association Members

The purpose of this study is to determine areas of agreement and disagreement among American Cleft Palate-Craniofacial Association (ACPA)members in the clinical practice of alveolar bone grafting (ABG), to guide further research to optimize ABG practices.

A cross-sectional survey was conducted.

The respondents were in an academic, combination, or private practice.

The respondents were either plastic or oral and maxillofacial surgeons (OMFS) from various countries.

A de-identified 24-question online survey was distributed to ACPA surgeon members utilizing the Research Electronic Data Capture (REDCap) tool.

Data collected included surgeon specialty, use of various alveolar bone graft surgical techniques, as well as protocols.

There was more variability than consensus between specialties with regards to the preoperative workup, timing of surgery, materials used for bone graft, surgical techniques, perioperative management, and postoperative evaluation. There was consensus on grafting during mixed dentition, not staging soft and hard tissue closure, and using iliac crest for primary and secondary grafting. Disagreements involved factors used to time the procedure and type of imaging used to assess viability. Technical differences involved incision type, part of bone grafted, use of minimally invasive technique, and material used for revisions.

Aside from areas of consensus among surgeons on ABG, several areas, including use of bone substitutes in revision grafting, incision and type of iliac crest graft used during initial grafting, and postoperative protocols, had no consensus. These areas should be targets of further research to determine if there truly is an optimal method to perform ABG.

The study was approved by the University of Illinois at Chicago Institutional Review Board. A de-identified 24-question online survey was distributed to surgeon members of the ACPA utilizing the REDCap tool on August 7, 2020. The survey questions consisted of multiple choice and multiple selection questions including an option to select "other" and specify the information in a blank space. Data collected included surgeon specialty, use of various alveolar bone graft surgical techniques, as well as pre and postoperative protocols. The full survey is included in online Supplemental material. Data analysis was performed in SPSS Statistics 27 (IBM Corp.). Descriptive statistics were performed, and chi-square was used to test for significant differences in survey responses between groups.

Evaluating SWAG and Its Validity When Compared to 3D Imagery of Secondarily Grafted Cleft Sites

OBJECTIVE

To test validity of 2D Standardized Way to Assess Grafts (SWAG) ratings to assess 3D outcomes of bone grafting (ABG).

PATIENTS

43 patients (34 UCLP, 9 BCLP) with non-syndromic complete clefts, bone-grafted at mean age 9yrs/3mos, with available post-graft occlusal radiographs and cone beam computed tomography (CBCT) (taken mean 4yrs/9mos post-ABG).

MAIN OUTCOME MEASURES

2D occlusal radiographs rated twice using SWAG by 6 calibrated raters. 12 scores were averaged and converted to a percentage reflecting bone-fill. Weighted Kappas were assessed for SWAG reliability. 3D cleft-site bone volume was calculated by 1 rater using ITK-SNAP. 13 cleft sites were re-measured by the 'one rater' for 3D reliability using Intraclass Correlation Coefficient (ICC). 2D versus 3D ratings were compared using paired t-test, independent samples t-test, Bland-Altman and Linear Regression. Significance level was P = .5.

RESULTS

2D reliability was 0.724 (intra-rater) and 0.546 (inter-rater). 3D reliability was 0.986. Bland-Altman plot comparing 2D vs 3D showed for 45 of 47 graft-sites were within 2 SD's. Mean % bone-fill was 64.11% with 2D and 69.06% with 3D (mean difference = 4.95%) that was a non-significant difference in both t-tests. Regression showed a statistically significant relation between the two methods (r2 = 0.46; P = .0001).

CONCLUSION

2D SWAG systematically and non-significantly underestimated bone-fill. There was a significant correlation between 2D/3D methods. Bland-Altman analysis illustrated the similarity of the two methods. For comparisons of group (cleft treatment Centers') bone grafting outcomes, the 2D method may suffice as a proxy for the 3D method. However, with individual variation up to 40% in 2D estimates of actual 3D volume, 2D SWAG method cannot be used in place of 3D images.

The orthodontic management of patients with cleft lip and palate: from birth to the late mixed dentition

This is the first of two papers outlining the orthodontic management of patients with cleft lip and palate. This paper will review orthodontic input into children with cleft lip and palate from birth to the late mixed dentition before definitive orthodontics. It will emphasise the importance of timing in alveolar bone grafting, the role of the general dental practitioner and the impact of timing on definitive orthodontic outcome.

The orthodontic management of patients with cleft lip and palate: from the permanent dentition and the adult returning to the service

This is the second of two papers outlining the orthodontic management of patients with cleft lip and palate. The first paper reviewed orthodontic input into children with cleft lip and palate from birth to the late mixed dentition before definitive orthodontics. In this second paper, I will discuss tooth management across the grafted cleft site and its impact on the bone graft itself. I will also discuss the some of the challenges of the adult patient returning to the service.

Rapid Maxillary Expansion Treatment in Patients with Cleft Lip and Palate: A Survey on Clinical Experience in the European Cleft Centers

Cleft lip and palate patients require complex interdisciplinary treatment, including maxillary expansion and secondary alveolar bone grafting. However, the evidence on these treatment procedures and outcomes is lacking. Therefore, this study aimed to survey the subjective observations of European maxillofacial surgeons and orthodontists on the maxillary expansion and bone grafting treatment protocols and the associated complications. An online questionnaire was sent to 131 centers. The questions assessed the participants' demographic data, maxillary expansion and alveolar bone grafting protocols, and the associated complications. Descriptive statistics and a t-test were used to analyze the data. The response rate was 40.5%. The average age for maxillary expansion was 9-10 years. The secondary alveolar bone grafting was planned 5-10 months after the expansion. The most common complications were asymmetric expansion, relapse, and fistula formation. The protocols and materials used vary widely among centers. Anatomical alterations and developmental processes, like tooth eruption adjacent to the cleft, should be seriously considered for treatment planning. This survey showed that there is still a lack of consensus on these treatment procedures. Further clinical trials should focus on long-term outcome evaluation to identify treatment components for optimal alveolar bone substitution and transversal maxillary expansion treatment in patients with clefts.

Effect of body mass index on progressive bone mineral density in patients with cleft after secondary alveolar bone grafting

BACKGROUND

Although childhood obesity matters, the association between body mass index (BMI) and bone mineral density (BMD) progression in grafted tissue after secondary alveolar bone grafting (ABG) for children with cleft alveolus is scarcely studied. Accordingly, this study explored the influence of BMI on BMD progression after ABG.

METHODS

In total, 39 patients with cleft alveolus receiving ABG at the mixed dentition stage were enrolled. Patients were classified as underweight, normal weight, or overweight or obese according to age- and sex-adjusted BMI. BMD was measured in Hounsfield units (HU) from cone-beam computed tomography scans obtained 6 months (T1) and 2 years (T2) postoperatively. Adjusted BMD (HU_{grafted tissue}/HU_pogonion, BMD_a) was used for further analysis.

RESULTS

For underweight, normal-weight, and overweight or obese patients, BMD_aT1 values were 72.87%, 91.85%, and 92.89%, respectively (p = 0.727); BMD_aT2 values were 111.49%, 112.57%, and 113.10% (p = 0.828); and density enhancement rates were 29.24%, 24.61%, and 22.14% (p = 0.936). No significant correlation was observed between BMI and BMD_aT1, BMD_aT2, or density enhancement rates (p = 0.223, 0.156, and 0.972, respectively). For patients with BMI < 17 and ≥ 17 kg/m², BMD_aT1 values were 89.80% and 92.89%, respectively (p = 0.496); BMD_aT2 values were 111.49% and 113.10% (p = 0.216); and density enhancement rates were 23.06% and 26.39% (p = 0.573).

CONCLUSION

Patients with different BMI values had similar outcomes (BMD_aT1, BMD_aT2, or density enhancement rate) after our ABG procedure in the 2-year postoperative follow-up.

A Comparative Volumetric Assessment of Cancellous and Cortico-Cancellous Bone Graft in the Management of Unilateral Alveolar Cleft Defect using Cone Beam Computed Tomographic Scan-A Randomized Controlled Trial

Introduction

The most commonly preferred procedure for surgical correction of alveolar bone defect and restoration of bony contour is anterior iliac crest graft. Since the ancient time, cancellous bone graft is considered as a gold standard, but it has a high resorption rate and many other disadvantages, and hence we conducted this study to evaluate the efficacy of Cortico-cancellous bone graft harvested from anterior iliac crest to find out whether it can be used as a substitute for cancellous bone graft or not.

Aims & Objectives

The objectives of present study were to compare and evaluate the bone bridge formation rate, resorption rate, and uptake of bone graft at recipient site using cancellous and corticocanellous bone graft harvested from anterior iliac crest for complete unilateral cleft alveolus defects.

Patients and Method

Total 20 patients were divided into two groups by lottery method of randomization. Each group comprises of total 10 patients treated with cancellous bone graft in group 1 and corticocancellous bone graft in group 2 patients harvested from anterior iliac crest. Preoperatively and postoperatively CBCT scans were taken for each patient to calculate the volume of cleft defect and volume of newly formed bone after 6 months, respectively. Grafting fill rate was calculated and mean graft filling rate observed in the patients of group 1 was 1.14 ± 0.03, and in patients of group 2, it was 1.17 ± 0.03. The mean bone bridge formation rate observed in the patients of group 1 was 91.85 ± 0.81 and in patients of group 2 it was 87.89 ± 0.75. The mean bone resorption rate obtained in the patients of group 1 was 18.74 ± 0.42 and in patients of group 2 it was 16.87 ± 0.52.

Conclusion

The present study concluded that accurate estimation of the amount required for bone grafting in the alveolar cleft can be performed by CBCT scan data using Planmeca Romexis viewer version 5.0 software. Even though the corticocancellous bone graft has some drawbacks, it is equally good as cancellous bone graft because of its less resorption than cancellous bone graft and can be considered as a second best option for secondary alveolar bone grafting.Clinical trial registration no (REF/2020/09/031605)/(CTRI/2020/09/028001).

Influence of a resorbable collagen membrane for alveolar bone graft on clinical outcomes and ridge volume stability in cleft alveolus

This study compared the clinical outcomes, graft quality, and graft quantity after alveolar bone grafting with and without a resorbable collagen membrane. Twenty unilateral cleft patients undergoing defect repair with cancellous iliac bone were assigned to either the collagen membrane group (Mb group) or standard group without a membrane (St group). Postoperative pain and swelling, bone density, and bone volume and quality were assessed. The Mb group showed significantly lower postoperative pain than the St group (P < 0.001) and significantly less swelling (P < 0.01) on day 3 postoperative. The reduction in bone density was significantly greater in the St group than in the Mb group at 1 and 3 months postoperative (P ≤ 0.001), but not at 6 months. The reduction in bone volume in the St group was significantly greater than that in the Mb group at 3 months (29.11 ± 6.26% vs 17.67 ± 11.89%, P = 0.016) and 6 months postoperative (40.95 ± 6.81% vs 25.67 ± 11.51%, P = 0.002). Nine cases in the Mb group versus six in the St group showed good bone quality. In conclusion, the collagen membrane facilitated predictable clinical outcomes in bone maturation, bone volume preservation, and bone bridging in the alveolar bone graft.

Anterior Dental Implant in Grafted Cleft Alveolus: A Clinical Comparison Between Intramembranous and Endochondral Bone Graft

BACKGROUND

Alveolar bone graft is usually performed during the early mixed dentition phase, at the chronological age of 6 to 8 years old, to reconstruct the cleft alveolus. As the appropriate time for implant placement is after completion of full growth, it can result in a likelihood of resorption. The aim of this study is to compare the clinical outcomes of anterior dental implants with delayed bone grafting using iliac crest (endochondral) and mandibular ramus or symphysis (intramembranous) bone in adolescents to adulthood patients with cleft alveolus.

MATERIALS AND METHODS

This study included 10 patients with cleft alveolus who underwent delayed bone grafting with autogenous block bone and particulate cancellous bone and marrow (PCBM) from the mandibular ramus and symphysis with dental implant placement, and iliac crest. The success of the treatment was evaluated through clinical and radiographic examination including marginal bone loss measurement of the implants.

RESULTS

All patients underwent delayed bone grafting between the ages of 11 and 21.1 years (mean age: 15.1±4.3 y). The implant diameters ranged from 3.8 to 4.5 mm and the lengths ranged from 8.0 to 11.5 mm. All of the implants were integrated successfully and survived during the 3-year follow-up period.

CONCLUSIONS

Delayed bone grafting followed by implant placement showed long-term stability with satisfactory esthetic and functional rehabilitation. One of the main advantages of delayed bone grafting is to achieve adequate bone support for future dental implant placements with less bone resorption compared with those of primary, early secondary, and secondary bone grafting.

The strategy of composite grafting with BMP2-Loaded calcium phosphate cements and autogenous bone for alveolar cleft reconstruction

Purpose: To remedy the drawbacks of traditional autogenous bone harvesting in alveolar bone grafting (ABG), a novel strategy of composite grafting with BMP2-loaded calcium phosphate cements (BMP2-CPC) and autogenous bone harvested by minimally invasive technique was developed and evaluated for its bone-repairing efficacy.

Materials and methods: A chart review was conducted for 19 patients with unilateral alveolar clefts who underwent secondary ABG from 2017 to 2020. Of the enrolled patients, 9 patients underwent grafting with autogenous bone harvested by traditional trap door technique (group I), and 10 patients underwent grafting with the composite graft comprising BMP2-CPC and autogenous bone harvested by minimally invasive technique at a ratio of 1:1 by volume (group II). The clinical performance of the composite graft was comprehensively evaluated in terms of clinical, radiographic and histological perspectives.

Results: The present results demonstrated that the composite graft exhibited satisfactory bone-repairing efficacy comparable to that of the autogenous bone graft on the premise of lower amount of harvested bone. The post-surgical resorption of bone volume and vertical height of grafted area was significantly slower in group II. The favourable resorption performance of BMP2-CPC contributed to preserving the post-surgical bony contour reconstructed with the composite graft.

Conclusion: The composite graft comprising BMP2-CPC and autogenous bone harvested by minimally invasive technique was demonstrated to be an eligible alternative for application in ABG, especially for its improved resorption performance in preserving post-surgical bony contour.

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.

"Improved Success Rate with Corticocancellous Block Compared to Cancellous-only Trephine Technique in Alveolar Bone Grafting from the Iliac Crest"

BACKGROUND

Alveolar bone grafting is an important component of cleft lip and palate treatment, with iliac crest as the most common donor site. Although studies have attempted to quantify alveolar bone graft resorption, few have directly compared the outcomes of graft techniques. This study compared the long-term success rates of corticocancellous block to trephine cancellous-only alveolar bone grafting from the iliac crest.

METHODS

A retrospective review of all cleft lip and palate patients undergoing alveolar bone grafting over 14 years was performed. Power analysis was performed to determine sample size. Data including patient demographics, surgical technique, need for repeat grafting, complications, length of hospitalization, and follow-up were collected. Statistical analyses of outcomes were performed based on initial graft technique.

RESULTS

A total of 106 initial operations met criteria, with 73 using trephine technique, 30 utilizing corticocancellous block, and 3 undergoing open cancellous harvest. The overall regraft rate was 40% with an average follow-up of 43.5 months. Patients with corticocancellous block grafting had significantly lower rates of repeat grafting compared to trephine technique (16.7% vs. 47.9%, p<0.001). There was no significant difference in complications rates or length of admission between treatment groups.

CONCLUSIONS

The use of corticocancellous block alveolar bone grafting demonstrated significantly higher success rates when compared to cancellous-only trephine techniques with no difference in complication rates. Although this must be weighed against the minor disadvantages of open iliac harvest, surgeons should consider incorporating en bloc corticocancellous bone to optimize outcomes in alveolar bone grafting.

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.

A Holistic Approach for the Identification of Success Factors in Secondary Cleft Osteoplasty

Cleft lip and palate belong to the most frequent craniofacial anomalies. Secondary osteoplasty is usually performed between 7 and 11 years with the closure of the osseus defect by autologous bone. Due to widespread occurrence of the defect in conjunction with its social significance due to possible esthetic impairments, the outcome of treatment is of substantial interest. The success of the treatment is determined by the precise rebuilding of the dental arch using autologous bone from the iliac crest. A detailed analysis of retrospective data disclosed a lack of essential and structured information to identify success factors for fast regeneration and specify the treatment. Moreover, according to the current status, no comparable process monitoring is possible during osteoplasty due to the lack of sensory systems. Therefore, a holistic approach was developed to determine the parameters for a successful treatment via the incorporation of patient data, the treatment sequences and sensor data gained by an attachable sensor module into a developed Dental Tech Space (DTS). This approach enables heterogeneous data sets to be linked inside of DTS, archiving and analysis, and is also for future considerations of respective patient-specific treatment plans.

Success rate of mid-secondary alveolar cleft reconstruction using anterior iliac bone grafts: A retrospective study

Introduction:

Bony reconstruction of the alveolar process and its adjacent platform largely represents the final step in surgical achievement of functionality and aesthetics in cleft patients. Throughout the years, the success of this procedure has been investigated. The aim of this study was to assess the success rate of autogenous mid-secondary alveolar bone grafting in this setting.

Methods and Material:

A retrospective cohort study was performed. All cleft patients receiving secondary alveolar bone grafts between 1990 and 2020 were reviewed. Criteria for assessing success were long-term preservation of alveolar bone stock, ability of spontaneous or orthodontic-guided eruption and periodontal health of permanent lateral incisors and canine teeth, absence of exposed root structures of neighbouring teeth, absence of fistula and successful placement of implants. Failure of alveolar bone grafts was indicated by radiographically demonstrable total or near-total graft loss requiring reintervention.

Results:

A number of 124 patients were included and grouped as those primarily operated following our (two-staged palatoplasty) protocol and those receiving cheilorhinoplasty and palatoplasty (one-staged) at other centres. Given the limited cohort size, no complex statistical analysis was performed. In the first group of 64 patients 12 experienced complications (Veau III, eight/36; Veau IV, four/18). In the second group of 60 patients, 12 experienced complications (Veau III, six/37; Veau IV, six/17).

Discussion:

Our surgical protocol using anterior iliac bone grafts for secondary alveolar reconstruction achieved good results, comparing favourably with previous literature.

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.

Progressive Comparison of Density Assessment of Alveolar Bone Graft in Patients with Unilateral and Bilateral Cleft

(1) Background: Continuing to observe the grafted bone mineral density (BMD) is essential to ensure the success of alveolar bone grafting (ABG) in patients with cleft lip and palate. This study elaborates on three methods that can be used to evaluate the progressive BMD. (2) Methods: Forty patients with unilateral or bilateral clefts receiving ABG were enrolled. Cone beam computed tomography (CBCT) scans were taken at 6 months (T1) and 2 years (T2) postoperatively. In CBCT, measurements were obtained on three different planes using the circle located 1 mm from the adjacent teeth (Method A), the largest circle within the defect (Method B), or the central circle with a diameter of 2 mm (Method C). The BMD was the average density of the three planes and was adjusted by pogonion density. Bland–Altman plots were used to evaluate the agreement of each method. Inter-rater reliability was confirmed by the intraclass correlation coefficient (ICC). (3) Results: For Method A, B, and C, the mean-adjusted BMD (BMD/pogonion density, BMD_a) was 17.44%, 17.88%, and 17.69%, respectively, at T1 (p = 0.495), and 22.51%, 22.87%, and 22.74%, respectively, at T2 (p = 0.690); the density enhancement rates were 40.54%, 38.92%, and 43.15% (p = 0.382). Significant differences between the BMD_a at T1 and T2 were observed (p < 0.001, <0.001, and 0.001, for Method A, B, and C, respectively). The volume of the grafted tissue remained stable during T1 and T2, and no significant correlation between density enhancement rate and volume loss was observed. (4) Conclusions: A significant increase in the BMD of grafted tissue was observed in the 2-year postoperative follow-up. The three methods for measuring BMD_a via CBCT can be applied in post-ABG evaluations.

Alveolar Cleft Reconstruction Using Double Iliac Corticocancellous Bone Plates Grafting Technique in Mixed Dentition Phase

OBJECTIVE

The primary goal of maxillary alveolar cleft reconstruction in patients with cleft lip/palate at the phase of mixed dentition is to build bone in the cleft area which in turn allows closure of the oronasal fistula, establishes arch continuity, and improve maxillary stability. This study aimed to evaluate the double iliac corticocancellous bone plates grafting technique for initial alveolar cleft grafting.

DESIGN

This prospective study was conducted on 12 consecutive patients with unilateral complete alveolar cleft and previous cleft lip and palate corrective surgery.

INTERVENTION

For all patients, the iliac crest graft was harvested and cut into 2 cortical bone plates and adapted labially and palatally. Both plates were fixed with screws then the gap between the 2 plates was filled with cancellous bone. The grafted side was compared to the contralateral side 9 months postoperatively regarding labio-palatal alveolar width and bone density, while the 9 months postoperative graft height was compared to the immediate postoperative height using computed tomography scans.

RESULTS

All grafted sides showed similarity to the contralateral sides regarding both alveolar width and bone density with minimal crestal bone resorption.

CONCLUSION

The double iliac corticocancellous bone plate grafting technique seems to be a reliable method for alveolar cleft reconstruction with adequate bone quality and contour.

Alveolar Volume Following Different Timings of Secondary Bone Grafting in Patients with Unilateral Cleft Lip and Palate. A Pilot Study

This study was intended to evaluate the relationship between secondary alveolar bone grafting (SABG) timing and the alveolar volume in patients with unilateral cleft lip and palate (UCLP). The material consisted of CTs of 35 patients (17 males, 18 females) with UCLP who underwent a one-stage primary cleft repair at a mean age of 8.4 months and SABG at different timings ranges of 1.8–18.8 years. The mean age at CT was 17.2 years. The relative coefficient (Ꞷ) which was independent from factors such as individual maxillary size, gender or age at the CT was introduced in order to compare volumes of the cleft-side in relation to the non-cleft-side alveolus. Pearson correlation coefficient r between Ꞷ coefficient and SABG timing was weak negative (r = −0.34, p = 0.045). The multiple regression analysis implied that the dependent variable-Ꞷ coefficient was associated with independent variables (cleft repair and SABG timings and age at CT) with r² = 0.228. Only patient’s age at SABG explained the dependent variable (p = 0.003). The study cautiously indicates a tendency to larger alveolar volume following earlier timing of SABG. Nevertheless, the further research on a larger group of patients should be performed before formulating any clinical indications.

Evaluation of the CBCT imaging accuracy in the volumetric assessment of unilateral alveolar cleft

INTRODUCTION

Appropriate radiographic evaluation is a fundamental step for determining the topography of the defect before the surgical intervention for alveolar bone grafting. Evaluation of cleft volume by CBCT has been done in dry skull samples in previous studies and it was recommended as an effective tool in the volumetric evaluation of the bone defect prior to the surgery. The purpose of this study was to evaluate the accuracy of preoperative clinical use of CBCT¹ imaging in determining the alveolar cleft volume.

MATERIAL AND METHODS

We performed a clinical study. 20 patients with unilateral alveolar cleft underwent preoperative radiographic evaluation using CBCT scan. Volumetric measurement was performed by an oral and maxillofacial radiologist using 0.5, 1, and 2 mm slices and an oral and maxillofacial surgeon using 2 mm slices. After the closure of the nasal floor and palatal mucosa, the alveolar defect was clinically measured with putty impression material. Descriptive and bivariate statistics were computed and the p-value was set at 0.05.

RESULTS

This study showed that there is a statistically significant difference between CBCT-estimated and clinical volumes of the alveolar cleft (paired T-test, p-value < 0.05).

CONCLUSION

Considering the significant difference between clinical and CBCT-estimated volumes of the alveolar cleft, CBCT imaging is not considered an accurate tool for pre-operative volumetric assessment of the alveolar cleft.

The Impact of Palatal Fistulae on the Success of Alveolar Bone Grafting

ABSTRACT

Palatal fistulae are common complications of cleft palate surgery with a frequency of 5% to 29% and are challenging to repair. Optimal timing to repair palatal fistulae, in a staged fashion before alveolar bone grafting, or at the same time, still remains controversial. The primary aim of this study is to compare outcomes of 2 groups with regard to successful alveolar bone grafting in patients with cleft lip and palate and palatal fistulae. We describe a review of 85 consecutive patients identified as undergoing bone grafting from a single institution craniofacial team during 2003 to 2018. Twenty-eight required palatal fistula repair. All patients had a diagnosis of unilateral or bilateral complete cleft lip and palate. Patients with cleft lip and palate repairs were stratified based on preoperative or simultaneous palatal fistula repair. Panoramic radiographs were reviewed by 2 physicians to evaluate success of bone grafting. Comparison between cohorts was made by statistical analysis. Of the 28 that required palatal fistula repair, 15 (53.6%) patients underwent prebone grafting palatal fistula repair and 13 (46.4%) patients underwent simultaneous bone grafting with palatal fistula repair. Mean age at time of bone grafting and palatal fistula repair were 10.60 years old and 9.39 years old, respectively. Length to follow-up was 54.82 months. The average height of the healed alveolar cleft site for patients in the prebone grafting or simultaneous groups was 10.57 mm and 11.46 mm, respectively. Patients who underwent palatal fistula repair and simultaneous bone grafting had similar outcomes as those with palatal fistula repair preoperatively.

Comparative Assessment of Autogenous Cancellous Bone Graft and Bovine-Derived Demineralized Bone Matrix for Secondary Alveolar Bone Grafting in Patients With Unilateral Cleft Lip and Palate

OBJECTIVE

Comparison between bovine-derived demineralized bone matrix (DMBM) and iliac crest graft over long term for secondary alveolar bone grafting (SABG) in patients with unilateral cleft lip and palate (UCLP) in terms of radiological and clinical outcomes.

DESIGN

Prospective, randomized, parallel groups, double-blind, controlled trial.

SETTING

Unit of Oral and Maxillofacial Surgery, Oral Health Science Centre, Postgraduate Institute of Medical Education & Research, Chandigarh.

PARTICIPANTS

Twenty patients with UCLP.

INTERVENTIONS

Patients were allocated into group I (Iliac crest bone graft) and group II (DMBM) for SABG. Outcomes were assessed at 2 weeks, 6 months, and then after mean follow-up period of 63 months.

OUTCOMES MEASURES

Volumetric analysis of the grafted bone in the alveolar cleft site was done through cone beam computed tomography using Cavalieri principle and modified assessment tool. Clinical assessment was performed in terms of pain, swelling, duration of hospital stay, cost of surgery, alar base symmetry, and donor site morbidity associated with iliac crest harvesting.

RESULTS

Volumetric analysis through Cavalieri principle revealed comparable bone uptake at follow-up of 6 months between group I (70%) and group II (69%). Modified assessment tool showed no significant difference between horizontal and vertical bone scores over short- and long-term follow-up. In group II, there was higher cost of surgery, but no donor site morbidity unlike group I.

CONCLUSIONS

Demineralized bone matrix proved analogous to iliac crest bone graft as per volumetric analysis over shorter period. However, although statistically insignificant, net bone volume achieved was lower than the iliac crest graft at longer follow-up.

Radiographic outcome of secondary alveolar bone grafting in patients with alveolar clefts

OBJECTIVE

To determine the outcome of secondary alveolar bone grafting (SABG) in a series of consecutive patients with clefts involving the alveolus.

DESIGN AND SETTING

Retrospective cohort study of consecutive operations performed between June 2011 and September 2016 by a single surgeon at a single United Kingdom cleft center.

PARTICIPANTS

A total of 160 patients with a cleft/s involving the alveolus, inclusive of syndromic patients and those with atypical facial clefts.

INTERVENTIONS

A standard protocol involved an oral hygiene program, pre-surgical orthodontics where necessary and autologous bone grafting from the iliac crest.

MAIN OUTCOME MEASURE(S)

The Kindelan bone-fill index was used to evaluate success using occlusal radiographs. Weighted Cohen's kappa coefficient was used as a measure of intra- and inter-rater agreement. Fisher's exact test was used to examine the effects of type of cleft, pre-surgical orthodontics or age at time of SABG on radiographic outcome.

RESULTS

There were 200 SABGs assessed. Mean age at time of SABG was 9.1 years old (SD 1.1) with 99% (n = 198) of grafts deemed successful. There were two failures where re-graft was performed successfully during the study period. A grade 1 outcome was achieved for 92.5% (n = 185) of grafts and this did not appear to be affected by type of cleft (P = .290), pre-surgical orthodontics (P = .380) or age at time of SABG (P = .081).

CONCLUSIONS

The high success rate reported in this study supports the favorable outcomes of a high-volume cleft surgeon. These findings can be used for comparative audit with similar units providing cleft care.

A Novel Bone Substitute Based on Recombinant Type I Collagen for Reconstruction of Alveolar Cleft

This study aimed to examine the optimal cross-link density of recombinant peptide (RCP) particles, based on human collagen type I, for bone reconstruction in human alveolar cleft. Low- (group 1), medium- (group 2), and high- (group 3) cross-linked RCP particles were prepared by altering the duration of the heat-dependent dehydration reaction. Rat palatine fissures (n = 45), analogous to human congenital bone defects, were examined to evaluate the potential of bone formation by the three different RCP particles. Microcomputed tomography images were obtained to measure bone volume and bone mineral density at 4, 8, 12, and 16 weeks post grafting. Specimens were obtained for histological analysis at 16 weeks after grafting. Additionally, alkaline phosphatase and tartrate acid phosphatase staining were performed to visualize the presence of osteoblasts and osteoclasts. At 16 weeks, bone volume, bone mineral density, and new bone area measurements in group 2 were significantly higher than in any other group. In addition, the number of osteoblasts and osteoclasts on the new bone surface in group 2 was significantly higher than in any other group. Our results demonstrated that medium cross-linking was more suitable for bone formation—and could be useful in human alveolar cleft repairs as well.

Mind the Gap: Alveolar Bone Graft Revision in the Era of Computed Tomography

OBJECTIVE

To determine the rate of revision alveolar bone grafting (ABG) in patients with cleft lip and palate (CLP) before and after the introduction of postoperative computed tomography (CT).

DESIGN

Retrospective case-control study analyzing the incidence of revision ABG in patients with and without postoperative CT scans for graft success evaluation.

SETTING

Academic tertiary care pediatric hospital.

PATIENTS

Eighty-seven patients with CLP or cleft lip and alveolus treated with autologous iliac crest bone grafting for alveolar clefts over a 10-year period (January 2009 to March 2019) with minimum 6-month follow-up. Fifty patients had postoperative CT evaluation; 37 did not.

INTERVENTIONS

Postoperative CT to determine ABG success, versus standard clinical examination and 2-dimensional radiographs.

MAIN OUTCOME MEASURES

Requirement for revision ABG, defined as failure of the original graft by clinical or radiographic examination.

RESULTS

Fifty-eight percent of patients underwent a postoperative CT scan at median interval of 10 months after surgery. Patients with postoperative CT evaluation had a 44% rate of revision ABG (22/50) for inadequate graft take, compared to 5% (2/37) in patients without postoperative CT (P < .001; 95% CT, 31%-58% in the CT group, 1%-16% in the non-CT group).

CONCLUSIONS

Computed tomography evaluation after ABG is associated with a significantly increased revision rate for inadequate graft take. The presence of a secondary palatal fistula at the time of original ABG is not associated with revision requirement. Lack of standardized dental and orthodontic records complicates the study of ABG outcomes and presents an area for systems-based improvement.

Closure of large alveolar defect by maxillary alveolar distraction using a vector-controlled distractor appliance in cleft patients: A pilot study

Objective

To assess the treatment outcome of custom made maxillary transport distractor appliance for closure of large alveolar clefts.

Method

A pilot study was conducted on 12 large alveolar cleft defects present in 11 non-syndromic cleft lip and palate patients (1 bilateral and 10 unilateral) in the age group of 16-25 years. All the subjects underwent pre-surgical orthodontics followed by alveolar distraction using custom-made distractor appliance. Study models, lateral cephalogram, panoramic radiograph and cone beam computed tomograms were obtained pre-surgically (T0) and after distractor removal (T1). The reduction in the width and volume of the alveolar cleft defect and change in the mesiodistal axial inclination of the teeth in transport segment following distraction were recorded. P value ​< ​0.05 was considered statistically significant.

Results

Significant reduction in cleft width (9.18 ​mm), volume (89.82 ​mm³) and the change in the mesiodistal axial inclination of the teeth in the transport segment (3.05°) (P ​< ​0.05) were observed. SNA (1.75°), ANB (1.58°), maxillary length (1.58 ​mm), upper incisor inclination (3°) and distal movement of anchorage teeth (0.95 ​mm) also showed significant change (P ​< ​0.05).

Conclusion

The custom-made tooth borne distraction appliance successfully closed the large alveolar cleft defect with minimal or no inadvertent effects on the oral tissues.

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.

Validation of a novel method for canine eruption assessment in unilateral cleft lip and palate patients

Objective

The aim of this study was to propose and validate a three‐dimensional (3D) methodology for the assessment of canine eruption in patients born with unilateral cleft lip and palate (UCLP) following secondary alveolar bone graft (SABG).

Methods and Materials

A total of 10 patients (four females, six males; mean age: 8.8 years) with UCLP who underwent SABG were recruited. Pre‐ and 6‐month post‐operative cone‐beam computed tomography (CBCT) was acquired for all patients. Post‐operative data was registered onto pre‐operative data utilizing voxel‐based registration. Following superimposition, a segmentation process was applied to segment maxillary canine on both cleft and non‐cleft side. Thereafter, translational and rotational changes in canine position were assessed for both cleft and non‐cleft side by two observers.

Results

The intra‐class correlation coefficient (ICC) indicated excellent reliability (≥0.90) with inter and intra‐observer error of less than 0.05 mm. The overall ICC was found to be high for assessing both translational and rotational changes. The mean absolute inter‐ and intra‐observer difference for translational and rotational changes was found to be less than 1 mm and 3°.

Conclusion

The present method was found to be reliable proving to be clinically applicable for assessing maxillary canine eruption changes in both cleft and non‐cleft bone.

Evaluation of density, volume, height and rate of bone resorption of substitutes of autologous bone grafts for the repair of alveolar clefts in humans: A systematic review

Objective

To assess clinical studies that compare synthetic or enriched natural materials to autologous osseous grafts among individuals with cleft lip and palate to determine which would be the substitute to autologous bone graft for alveolar cleft repair in humans.

Materials and methods

Randomized and controlled clinical trials on alveolar clefts treated with synthetic bone substitutes and autogenous bone grafts combined with osteoinductive factors compared with autogenous bone grafts alone (with ≥4-month follow-up and reporting clinical/radiographic data) were considered eligible. MEDLINE, EMBASE, and Central databases were searched for articles published until February 2020.

Results

Of 73 eligible articles, 15 were included. Some inductive factors along with iliac crest bone decreased bone reabsorption, preserved the generated bone height/width, and reduced the required autologous bone graft volume. Bone morphogenetic protein (BMP2) as an autologous bone graft substitute, demonstrated satisfactory alveolar defect healing, by avoiding autograft use. Many materials did not yield better outcomes than did autologous grafts; however, hydroxyapatite and collagen complex, hydroxyapatite agarose composite gel, acellular dermal matrix film, fibrin glue, platelet-rich plasma, and deproteinized bovine bone showed similar bone healing outcomes, being an alternative alveolar defect treatment.

Conclusions

BMP2, as an osteoinductive factor along with a synthetic matrix, yields satisfactory bone healing and avoids the need for autologous bone grafts. However, high-quality RCTs are necessary to determine the most effective and safe concentration and protocol of BMP2 utilization as a substitute for the autologous iliac crest bone grafting.

Comparison of dental outcomes in patients with nonsyndromic complete unilateral cleft lip and palate who receive secondary alveolar bone grafting before or after emergence of the permanent maxillary canine

INTRODUCTION

For patients with complete unilateral cleft lip and palate (CUCLP), secondary alveolar bone grafting (SABG) can be performed before or after the emergence of the cleft side permanent canine (pre-CE and post-CE, respectively). The controversy regarding dental outcomes related to the timing of SABG remains unsettled. The objective of this study was to evaluate dental survival and specific dental outcomes of cleft-adjacent teeth in children with CUCLP who received either pre-CE or post-CE SABG.

METHODS

The permanent maxillary canines and the central and lateral incisors of 21 pre-CE and 23 post-CE SABG subjects with nonsyndromic CUCLP and all cleft-related surgeries performed by the same surgeon were analyzed retrospectively. Intraoral radiographs and clinical chart notes were collected at age 7 years, at the time of the SABG, and approximately 4 years after the grafting. Dental survival, spontaneous canine eruption, planned prosthetic replacement, root development, and root resorption were analyzed.

RESULTS

Dental outcomes on the noncleft side were better than those on the cleft side. On the cleft side, dental survival of the cleft-adjacent teeth was not significantly different between the pre-CE and post-CE SABG groups (P >0.05). Most teeth completed root development after grafting, and the cleft side canine root development in the pre-CE SABG group appeared to accelerate after SABG. Trends showed that the pre-CE SABG group suffered less root resorption (16.28%; post-CE: 22.73%; P >0.05) and received fewer planned prosthetic replacements (14.29%; post-CE: 26.01%; P >0.05) but required a greater number of canine exposures (33.33%; post-CE: 4.55%; P = 0.02).

CONCLUSIONS

Pre-CE SABG showed better dental outcomes in patients with CUCLP, with fewer adverse dental outcomes than post-CE SABG.

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.

Comparison of early and conventional autogenous secondary alveolar bone graft in children with cleft lip and palate: A systematic review

PURPOSE

The literature is scarce on studies comparing secondary alveolar bone graft (SABG) performed early at approximately 5-6 years and at the conventional time at 9-11 years. This systematic literature review(SLR) aimed to compare clinical outcomes after two different timings of SABG in children with unilateral and bilateral cleft lip and palate.

METHODS

The inclusion criteria were autogenous iliac grafts and the following study designs: case control, cohort, clinical controlled trial (CCT), randomized CCT (RCCT), and previous SLRs. Ovid MEDLINE, Ovid EMBASE, Web of Science, Scopus, Cochrane, ProQuest and Google Scholar were the primary databases. Two calibrated examiners worked independently to select the articles. The MINORS evaluation method for surgical non-RCTs was used to assess for quality.

RESULTS

1,111 articles were retrieved and 19 qualified. Different clinical and radiographic outcomes such as bone level, periodontal status, canine eruption and cleft-side tooth survival were evaluated by different assessment methods such as CBCT volume, computed tomography, periodontal evaluation, panoramic, intraoral radiographs, and Bergland scale. No RCCT or meta-analysis was found. None of the studies received the ideal score, which is 16 for non-comparison studies and 24 for comparison studies.

CONCLUSION

Methodological variation, lack of standardization for initial cleft dimension and low-quality level rendered a fair comparison unfeasible. Although further studies are necessary, it can be assumed that early SABG also can be an acceptable option, but this was based on a single study with a reasonable level of evidence.

Comparison of 2- and 3-dimensional radiologic evaluation of secondary alveolar bone grafting of clefts: a systematic review

OBJECTIVE

Secondary alveolar bone grafting (SABG) has become the principal means of treating alveolar cleft defects. We reviewed the literature on 2-dimensional (2-D) and 3-dimensional (3-D) radiographic evaluation of SABG in patients with cleft lip and alveolus (CLA) and those with cleft lip and palate (CLP), with a focus on outcomes.

STUDY DESIGN

We searched several electronic databases to the end of 2018. The inclusion criteria were nonsyndromic CLA or CLP treated with SABG at an optimal age and evaluation performed no earlier than 3 months postoperatively. Study quality was evaluated by using the Methodological Index for Non-Randomized Studies and the Cochrane Collaboration tool.

RESULTS

We identified 282 articles from 3 databases. Full texts of 102 articles were analyzed, and finally 11 articles were included for qualitative analysis. 2-D and 3-D radiographic evaluations were performed in each study. Traditional 2-D radiographic imaging tended to overestimate success; bone resorption in the labiopalatal direction was inaccurate in 2-D views. Most articles were observational in nature and of moderate methodologic quality.

CONCLUSIONS

2-D evaluation tended to overestimate SABG outcomes; 3-D evaluation was more precise and reliable than 2-D radiography. A gold standard 3-D evaluation protocol is required for quantitative comparisons in the future.

An Accurate Volumetric Analysis Method for Evaluating Outcomes of Alveolar Cleft Reconstruction

An accurate volumetric analysis method for evaluating the outcomes of different types of alveolar cleft reconstruction is essential because it can help determine which graft material is more effective, confirm favorable times for alveolar bone grafting, and improve surgical techniques. This study aimed to introduce a novel method of precisely calculating the bone formation ratio using computer-aided engineering after surgery. A patient with a unilateral alveolar cleft who was treated with anterior iliac crest bone grafting was enrolled in this study. Helical computed tomography scans were performed preoperatively and 12 months postoperatively. The Digital Imaging and Communications in Medicine (DICOM) data were reconstructed as three-dimensional images and saved in the STL format by using Mimics software. STL data were processed by Geomagic Wrap 2017, using the Boolean operation, the newly formed bone of the alveolar was segmented by identifying the differences between the preoperative and the postoperative three-dimensional images. For this patient, the mean volume of the newly formed bone was 0.387 cm, the morphology was clear, the bone formation ratio was 41.4%, the mean time required for calculating the newly formed bone volume was 23 minutes, and the bone survival ratio was 38.7%. This method is a clinically practical, accurately measurement and time-saving method to evaluate the outcome of alveolar cleft reconstruction. Both the volumetric assessment and morphological analysis of the newly formed bone could be determined in a precise manner.

A novel accurate volumetric analysis protocol for evaluating secondary alveolar cleft reconstruction

An accurate volumetric analysis protocol for secondary alveolar cleft reconstruction is essential. It can help confirm favorable times for bone grafting, determine which graft material is more effective, and improve surgical techniques. This study aimed to introduce a novel protocol for precisely calculating the bone formation ratio (BF%) using computer-aided engineering. The helical computed tomography (CT) datasets of 14 patients who underwent alveolar cleft reconstruction was included in this study. CT scans performed preoperatively and 1 year postoperatively were evaluated by two investigators. Digital Imaging and Communications in Medicine (DICOM) data were reconstructed as three-dimensional (3D) images using Mimics software and processed by Geomagic Wrap (2017). Using the Boolean operation, the newly formed bone of the alveolar cleft was segmented by identifying the differences between pre- and postoperative 3D images. The volumetric assessment and morphological analysis of the newly formed bone could be determined in a precise manner, the mean BF% was 47.7% ± 16.4%, the mean time required for calculating was 23.57 ± 3.64 min. For the difference in the volume of newly formed bone between the two observers, the intraclass correlation coefficient (ICC) was 0.92, p < 0.001. This method is clinically practical and precise measurement, which has good reproducibility for evaluating outcome of different grafting materials for alveolar clefts.

A novel success scale for evaluating alveolar cleft repair using cone-beam computed tomography

PURPOSE

Radiographic scales, based on plain radiographs, for the evaluation of alveolar cleft repair, have certain weaknesses and are thought to overestimate to some degree the success of the surgical intervention. The aim of this study was the presentation of a novel success scale for evaluating alveolar cleft repair using cone-beam computed tomography (CBCT).

MATERIALS AND METHODS

Patients treated with secondary osteoplasty for unilateral or bilateral alveolar cleft were evaluated using the Bergland and Enemark scales, as well as the novel success scale, which measures the bone height, the bone width and the level of the nasal floor.

RESULTS

A total of 44 patients with a total of 53 alveolar cleft sites were included. According to the new scale, 60% of the cases were defined as successful, with moderate (kappa = 0.511) or substantial (kappa = 0.718) agreement, between the new scale and the Bergland or Enemark scale, respectively. Statistically significant correlation was reported between the new success scale and the closure of space of the lateral incisor, the patient's age at surgery, the graft revision and the presence of residual fistula.

CONCLUSIONS

The novel success scale for evaluating alveolar cleft repair using CBCT takes into consideration all dimensions of the bony bridge. Future application is necessary for validation of its potential value.

Regeneration of a Pediatric Alveolar Cleft Model Using Three-Dimensionally Printed Bioceramic Scaffolds and Osteogenic Agents: Comparison of Dipyridamole and rhBMP-2

BACKGROUND

Alveolar clefts are traditionally treated with secondary bone grafting, but this is associated with morbidity and graft resorption. Although recombinant human bone morphogenetic protein-2 (rhBMP-2) is under investigation for alveolar cleft repair, safety concerns remain. Dipyridamole is an adenosine receptor indirect agonist with known osteogenic potential. This study compared dipyridamole to rhBMP-2 at alveolar cleft defects delivered using bioceramic scaffolds.

METHODS

Skeletally immature New Zealand White rabbits underwent unilateral, 3.5 × 3.5-mm alveolar resection adjacent to the growing suture. Five served as negative controls. The remaining defects were reconstructed with three-dimensionally printed bioceramic scaffolds coated with 1000 μm of dipyridamole (n = 6), 10,000 μm of dipyridamole (n = 7), or 0.2 mg/ml of rhBMP-2 (n = 5). At 8 weeks, new bone was quantified. Nondecalcified histologic evaluation was performed, and new bone was evaluated mechanically. Statistical analysis was performed using a generalized linear mixed model and the Wilcoxon rank sum test.

RESULTS

Negative controls did not heal, whereas new bone formation bridged all three-dimensionally printed bioceramic treatment groups. The 1000-μm dipyridamole scaffolds regenerated 28.03 ± 7.38 percent, 10,000-μm dipyridamole scaffolds regenerated 36.18 ± 6.83 percent (1000 μm versus 10,000 μm dipyridamole; p = 0.104), and rhBMP-2-coated scaffolds regenerated 37.17 ± 16.69 percent bone (p = 0.124 versus 1000 μm dipyridamole, and p = 0.938 versus 10,000 μm dipyridamole). On histology/electron microscopy, no changes in suture biology were evident for dipyridamole, whereas rhBMP-2 demonstrated early signs of suture fusion. Healing was highly cellular and vascularized across all groups. No statistical differences in mechanical properties were observed between either dipyridamole or rhBMP-2 compared with native bone.

CONCLUSION

Dipyridamole generates new bone without osteolysis and early suture fusion associated with rhBMP-2 in skeletally immature bone defects.

Rat Palatine Fissure: A Suitable Experimental Model for Evaluating Bone Regeneration

IMPACT STATEMENT

The rat palatine fissure is anatomically similar to human alveolar cleft. In this study, we examined potential bone repair by an autologous bone implant and beta-tricalcium phosphate (β-TCP) using rat palatine fissure as a model. Autologous bone chips or β-TCP granules were implanted into the rat palatine fissure. Our model demonstrated that higher bone volume and bone mineral density were achieved with autologous bone graft than with β-TCP. We have provided the first demonstration of the suitability of the rat palatine fissure as the implant site to simulate the transplantation of bone graft materials into human alveolar cleft.

Assessment of Bioabsorbable Hydroxyapatite for Secondary Bone Grafting in Unilateral Alveolar Clefts

PURPOSE

To evaluate the utility and efficacy of bioabsorbable hydroxyapatite and collagen complex (HA/Col) for secondary bone grafting in unilateral alveolar clefts.

PATIENTS AND METHODS

Between 2015 and 2016, 21 patients with unilateral cleft lips and alveolar clefts were enrolled. In group I, a cancellous iliac bone graft was placed at the alveolar cleft (6 males, 5 females). In group II, a bioabsorbable HA/Col was placed at the alveolar cleft (4 males, 7 females).

RESULTS

The groups did not differ in age, cleft volume, or surgical duration. There was a significant difference in intraoperative blood loss between the 2 groups (6.7 ± 1.89 mL in group II vs 38.8 ± 9.73 mL in group I [P < .01]). The use of patient-controlled intravenous analgesia was also significantly lower in group II than in group I (2.2 ± 1.9 times vs 12.2 ± 4.4 times [P < .01]). Only 1 female in group II who had maxillary sinusitis did not achieve osteosynthesis. With the exception of this patient, the 12-month bone volumes in groups I and II were 0.567 ± 0.066 and 0.596 ± 0.073 mL, respectively, without significant difference (P = .18).

CONCLUSION

Compared with an autogenous bone, bioabsorbable HA/Col significantly reduces postoperative pain. In addition, the use of HA/Col alone produced the same result as an autologous bone and is effective in filling the alveolar cleft.