A Novel Semiautomatic Technique for Volumetric Assessment of the Alveolar Bone Defect Using Cone Beam Computed Tomography

Adaptable cascaded registration for personalized maxilla completion and cleft defect volume estimation

BACKGROUND

Cone-beam computed tomography (CBCT) images provide high-resolution insights into the underlying craniofacial anomaly in patients with cleft lip and palate (CLP), requiring non-negligible annotation costs to measure the cleft defect for the guidance of the clinical secondary alveolar bone graft procedures. Considering the cumbersome volumetric image acquisition, there is a lack of paired CLP CBCTs and normal CBCTs for learning-based anatomical structure restoration models. Nowadays, the registration-based method relieves the annotation burden, though one-shot registration and the regular mask are limited to handling fine-grained shape variations and harmony between restored bony tissues and the defected maxilla.

PURPOSE

This study aimed to design and evaluate a novel method for deformable partial registration of the CLP CBCTs and normal CBCTs, enabling personalized maxilla completion and cleft defect volume prediction from CLP CBCTs.

METHODS

We proposed an adaptable deep registration framework for personalized maxilla completion and cleft defect volume prediction from CLP CBCTs. The key ingredient was a cascaded partial registration to exploit the maxillary morphology prior and attribute transfer. Cascaded registration with coarse-to-fine registration fields handled morphological variations of cleft defects and fine-grained maxillary restoration. We designed an adaptable cleft defect mask and volumetric Boolean operators for reliable voxel filling of the defected maxilla. A total of 36 clinically obtained CLP CBCTs were used to train and validate the proposed model, among which 22 CLP CBCTs were used to generate a training dataset with 440 synthetic CBCTs by B-spline deformation-based data augmentation and the remaining for testing. The proposed model was evaluated on maxilla completion and cleft defect volume prediction from clinically obtained unilateral and bilateral CLP CBCTs.

RESULTS

Extensive experiments demonstrated the effectiveness of the adaptable cleft defect mask and the cascaded partial registration on maxilla completion and cleft defect volume prediction. The proposed method achieved state-of-the-art performances with the Dice similarity coefficient of 0.90 ± $\pm$ 0.02 on the restored maxilla and 0.84 ± $\pm$ 0.04 on the estimated cleft defect, respectively. The average Hausdorff distance between the estimated cleft defect and the manually annotated ground truth was 0.30 ± $\pm$ 0.08 mm. The relative volume error of the cleft defect was0.09 ± $0.09\pm$ 0.08. The proposed model allowed for the prediction of cleft defect maps that were in line with the ground truth in the challenging unilateral and bilateral CLP CBCTs.

CONCLUSIONS

The results suggest that the proposed adaptable deep registration model enables patient-specific maxilla completion and automatic annotation of cleft defects, relieving tedious voxel-wise annotation and image acquisition burdens.

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.

Cone Beam-CT-Based Bone Volume Assessments of Alveolar Synthetic Bone Graft GlassBONE™ in Cleft Lip and Palate Patients: A Retrospective Study

Background

Clefts of the lip and palate (CLP) are facial deformities that require multiple surgical procedures during childhood. One of these steps consists of filling the alveolar space with bone graft, traditionally removed from the iliac crest. However, this procedure could be invasive in children.

Aim

Here, we aimed to evaluate the outcomes of GlassBONE™ graft, a bioactive glass used as a bone substitute, as an alternative to the deleterious autologous bone graft in children.

Materials & methods

Retrospective monocentric study with 17 children aged 7.5 ± 2.2 yo [3.8-13.3 yo] carrying CLP. This technique has been established at La Timone Children hospital (Assistance Publique - Hôpitaux de Marseille) since 2011. Clinical (scar, graft rejection and periodontal status) and radiological (both panoramic radiographs and cone beam-CT) follow-up was conducted one year after the graft. The primary outcome was the reduction of the cleft volume, and secondary was the eruption of the adjacent tooth through the graft.

Results

GlassBONE™ permitted a significant reduction in the cleft volume by 42.4 ± 27.7% [0.6-81.1%] (p < 0.0001), corresponding to a filling of 57.6 ± 27.7% of the alveolar cleft. GlassBONE™ is well tolerated, ensuring satifactory clinical results (improvement in both scar and periodontal coverage), as well as the physiological evolution of the germs through the biomaterial. GlassBONE™ appears particularly suitable for small volumes, and we were able to determine a minimum volume of approximtely 0.259 + / - 0.155 cc required for a successful bone fusion.

Conclusion

The bioactive glass GlassBONE™ could be safely used in children with small CLP cases, providing satisfactory clinical and radiological results.

Residual calcified material volume of β-tricalcium phosphate with platelet-rich fibrin in unilateral alveolar bone graft

BACKGROUND

This study aimed to evaluate the effectiveness of β-tricalcium phosphate (β-TCP) and platelet-rich fibrin (PRF) in unilateral alveolar bone graft, involving the percentage of residual calcified material and the average labiopalatal thickness of the grafts on cone beam computed tomography at 6 months after surgery, comparing two age groups 12 years and under and over 12 years old.

RESULTS

The mean preoperative defect volume was 0.93 ± 0.20 cm3, with no significant difference between the two groups (p = 0.652). In the postoperative period, we did not record any abnormal bleeding and no infection was observed. Six months after surgery, the mean percentage of residual calcified material was 63.53 ± 16.48% with a significantly higher difference in the age group 12 and under (p < 0.001), and the mean average labiopalatal thickness of the grafted bone was 5.72 ± 1.09 mm with a significantly higher difference in the age group 12 and under (p = 0.011).

CONCLUSION

Using β-TCP and PRF in alveolar bone graft surgery has acceptable effectiveness clinically and on CBCT images, with significantly higher differences of the percentage of residual calcified material and the average labiopalatal thickness of the grafted bone in the group 12 years old and younger than in the older group.

Harnessing the Power of Artificial Intelligence in Cleft Lip and Palate: An In-Depth Analysis from Diagnosis to Treatment, a Comprehensive Review

Cleft lip and palate (CLP) is the most common craniofacial malformation, with a range of physical, psychological, and aesthetic consequences. In this comprehensive review, our main objective is to thoroughly examine the relationship between CLP anomalies and the use of artificial intelligence (AI) in children. Additionally, we aim to explore how the integration of AI technology can bring about significant advancements in the fields of diagnosis, treatment methods, and predictive outcomes. By analyzing the existing evidence, we will highlight state-of-the-art algorithms and predictive AI models that play a crucial role in achieving precise diagnosis, susceptibility assessment, and treatment planning for children with CLP anomalies. Our focus will specifically be on the efficacy of alveolar bone graft and orthodontic interventions. The findings of this review showed that deep learning (DL) models revolutionize the diagnostic process, predict susceptibility to CLP, and enhance alveolar bone grafts and orthodontic treatment. DL models surpass human capabilities in terms of precision, and AI algorithms applied to large datasets can uncover the intricate genetic and environmental factors contributing to CLP. Additionally, Machine learning aids in preoperative planning for alveolar bone grafts and provides personalized treatment plans in orthodontic treatment. In conclusion, these advancements inspire optimism for a future where AI seamlessly integrates with CLP management, augmenting its analytical capabilities.

Alveolar cleft reconstruction utilizing a particulate autogenous tooth graft and a novel split-thickness papilla curtain flap - A retrospective study

During secondary alveolar cleft grafting, the use of autogenous cancellous bone harvested from the iliac crest is still considered the gold standard. Due to the risk of donor-site morbidity and excessive graft resorption, alternative grafting materials (e.g. intraoral bone, xenografts) have been tested. Autogenous tooth bone graft (ATB) is a novel material derived from extracted teeth. ATB has successfully been used in pre-prosthetic and periodontal surgery for hard-tissue reconstruction. Seven patients with unilateral cleft lip and palate were treated with ATB, using their own deciduous teeth for grafting. Defects were accessed utilizing a novel split-thickness papilla curtain flap. Cone-beam computed tomography scans were taken prior to and 3 months following cleft surgery to assess graft integration, graft stability, and the volume of the newly formed hard tissues. Hard-tissue gain, as measured at the 3-month follow-up, averaged 0.65 cm3 ± 0.26 cm3. Results showed acceptable graft integration and stability at the 3-month follow-up, with no adverse effects or excessive resorption of the graft. The use of ATB might be a feasible alternative for alveolar cleft grafting. However, long-term studies using a large sample size are required to derive further conclusions.

Alveolar cleft reconstruction using bone marrow aspirate concentrate and iliac cancellous bone: A 12-month randomized clinical study

OBJECTIVE

This study aimed to compare the bone density and volume in patients with alveolar cleft reconstructions utilizing bone marrow aspirate concentrate with iliac graft versus iliac graft alone.

MATERIAL AND METHODS

Thirty-six patients with unilateral alveolar cleft were randomly allocated into either an intervention group receiving an iliac bone graft mixed with bone marrow concentrate or a control group receiving an iliac bone graft. Cone beam CT was obtained preoperative, 6 and 12 months postoperatively to assess the bone density of the graft and bone volume of the alveolar defect, and then, the bone loss ratio was calculated.

RESULTS

Bone volume and bone density demonstrated a statistically significant increase in the intervention group at 6 and 12 months. In contrast, the bone loss ratio decreased significantly in the intervention group throughout the follow-up period.

CONCLUSION

A combination of bone marrow concentrate and iliac cancellous bone in alveolar cleft reconstruction may improve bone densities and volume in addition to decreasing graft loss rate.

CLINICAL SIGNIFICANCE

Using of bone marrow aspirate concentrate will decrease the amount of the graft needed and decrease the ratio of bone loss at the grafted site by the time. Trial registration ClinicalTrials.org ( NCT04414423 ) 4/6/2020.

Interpretable artificial intelligence for classification of alveolar bone defect in patients with cleft lip and palate

Cleft lip and/or palate (CLP) is the most common congenital craniofacial anomaly and requires bone grafting of the alveolar cleft. This study aimed to develop a novel classification algorithm to assess the severity of alveolar bone defects in patients with CLP using three-dimensional (3D) surface models and to demonstrate through an interpretable artificial intelligence (AI)-based algorithm the decisions provided by the classifier. Cone-beam computed tomography scans of 194 patients with CLP were used to train and test the performance of an automatic classification of the severity of alveolar bone defect. The shape, height, and width of the alveolar bone defect were assessed in automatically segmented maxillary 3D surface models to determine the ground truth classification index of its severity. The novel classifier algorithm renders the 3D surface models from different viewpoints and captures 2D image snapshots fed into a 2D Convolutional Neural Network. An interpretable AI algorithm was developed that uses features from each view and aggregated via Attention Layers to explain the classification. The precision, recall and F-1 score were 0.823, 0.816, and 0.817, respectively, with agreement ranging from 97.4 to 100% on the severity index within 1 group difference. The new classifier and interpretable AI algorithm presented satisfactory accuracy to classify the severity of alveolar bone defect morphology using 3D surface models of patients with CLP and graphically displaying the features that were considered during the deep learning model's classification decision.

A CBCT Based Assessment of Canine Eruption and Development Following Alveolar Bone Grafting in Patients Born With Unilateral Cleft lip and/or Palate

To three-dimensionally assess and visualize the eruption path and development of the maxillary canine following alveolar bone grafting in patients born with cleft lip and palate. A further objective of this analysis was to assess how the presence of the lateral incisor impacts the eruption path of the canine.

Observational follow-up study.

Stockholm Craniofacial Team, Karolinska University Hospital, Sweden.

Thirty children born with non-syndromic unilateral cleft lip with or without palate were consecutively included.

CBCT scans of the maxilla were taken six months before and six months after the alveolar bone-grafting surgery for each patient.

Canine eruption (angulation and vertical movement) and canine development (length and volume).

There was a significant difference pre- and post-operatively of the canine angulation between the cleft and non-cleft sides. The mean angulation on the cleft side was 14.7° (SD  =  11.1°) while on the non-cleft side, it was 4.9° (SD  =  9.2°). No significant differences were noted between cleft-side and non-cleft side canines in terms of amount of vertical eruption and volumetric development. Absence of the lateral incisor did not significantly contribute to either canine angulation or its vertical eruption on the cleft-side.

Higher angulation of the canine on the cleft side indicates a higher risk of future canine impaction. Presence or absence of the lateral incisor did not significantly affect canine angulation or its vertical eruption. Increased age and children born with total cleft lip and palate imply a higher risk of angulated canines on the cleft side.

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).

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.

A novel approach to assess volumetric bone loss at immediate implant sites and comparison to linear measurements: a pilot study and measurement workflow

OBJECTIVES

Studies have evaluated changes in hard tissue following immediate implant placement (IIP) through cone beam computed tomography (CBCT) imaging, typically examining the amount of two-dimensional (2D) linear, rather than three-dimensional (3D) volumetric bone loss. This study compared the 3D volumetric changes of the alveolar bone at immediate implant sites with 2D linear measurement outcomes by using a novel image analysis workflow.

METHODS

Preoperative and 6-month postoperative CBCT images of patients who underwent IIP and bone grafting in the maxillary esthetic area were acquired. Linear and volumetric measurements of buccal bone dimensions were taken using a specially designed workflow. The 2D and 3D measurements were compared, and their correlations were determined.

RESULTS

Images from 13 patients (13 implants) were analyzed. Linear measurements revealed that the general linear buccal bone loss was less than 1mm in all segments. The 3D volumetric bone reduction (reported as median [first quantile, third quantile]) in the vertical, cervical, middle, and apical segments was 14.27 [11.33, 30.66] mm³ (51.30 [42.78, 66.91]%), 16.20 [10.35, 30.52] mm³ (18.20 [9.88, 24.74]%), 17.48 [8.42, 21.17] mm³ (24.05 [12.39, 28.22]%), and 6.87 [3.88, 9.45] mm³ (11.34 [5.14, 22.54]%), respectively. Significant positive correlations between 2D and 3D measurements were consistently identified in the cervical and middle segments, but no significant correlation was noted in the vertical segment.

CONCLUSIONS

The results revealed that linear measurements could not fully represent volumetric bone dimensional changes. Performing volumetric measurements and 3D rendering could be valuable in presenting the actual amount and topography of peri-implant bone remodeling.

CLINICAL SIGNIFICANCE

Linear measurements only partially represent the real-life event of 3D bone changes at immediate implant sites. Factors affecting hard tissue alterations following IIP should be reassessed using 3D volumetric measurement outcomes.

A Novel and Practical Protocol for Three-Dimensional Assessment of Alveolar Cleft Grafting Procedures

OBJECTIVE

To evaluate the reproducibility and accuracy of a new, easy-to-use volumetric assessment of the alveolar cleft.

DESIGN

Twelve cone-beam computed tomography (CBCT) datasets of patients with a unilateral cleft lip, alveolus, and palate were evaluated by two investigators. Residual alveolar cleft calcified volume one year after surgery was analyzed by using standardized landmarks to determine the borders of the cleft defect and semi-automatically segment the alveolar cleft defect.

RESULTS

The Dice-coefficient between observers for the segmented preoperative alveolar cleft defect was 0.81. Average percentage of residual alveolar cleft calcified material was 66.7% one year postoperatively.

CONCLUSIONS

This study demonstrates a reliable and practical semi-automatic three-dimensional volumetric assessment method for unilateral clefts using CBCT.

Evaluation of 3D visualization, planning and printing techniques in alveolar cleft repair, and their effect on patients' burden

BACKGROUNDS

The aim of this study was to describe our auxiliary surgical techniques in alveolar cleft reconstruction and evaluate the patients burden after 3 years of surgical experience.

METHODS

At the Cleft center, Semmelweis University Budapest, 28 patients underwent alveolar bone grafting between September 2017 and September 2020. We have used CBCT scans and computer software to perform 3D simulation of the alveolar defect and planning of patient- and defect specific grafts. An individual graft mold was designed for each alveolar defect and 3D printed for intra-operative use. During the surgical intervention, the mold was used to harvest the most appropriate amount and precise shape of graft material. We used cancellous iliac crest graft. After performing a descriptive statistical analysis of our patient group, we used a quality-of-life questionnaire to measure the patient's self-perception.

RESULTS

In all cases the treatment sequence could be applied, planning and surgery was successful and uneventful. Patients did not experience more pain, bleeding or any feeding impairment. No inflammatory or wound healing reactions were observed. There were no major adverse effects causing permanent problems.

CONCLUSIONS

Our follow-up and patient satisfaction questionnaire showed that our treatment sequence with auxiliary techniques brought no further burden to the patients care and hospitalization, even though it is more complex. Efficacy of this treatment method and improvement in graft integration has yet to be determined.

Evaluation of the Effectiveness of Using Platelet Rich Fibrin (PRF) With Bone Graft in the Reconstruction of Alveolar Cleft, A Prospective Study

Clefts of the lip, alveolus, and palate are the most common congenital malformation of the orofacial region. Bone grafting of the alveolar cleft is necessary for rehabilitation of oral function. Platelet rich fibrin (PRF), an autologous fibrin matrix is a second-generation platelet concentrate that has a positive effect on bone healing.

AIM OF THE STUDY

The aim of this prospective study is to investigate and evaluate the quality and quantity of the bone graft that mixed with PRF when used in reconstruction of alveolar cleft in terms of bone density and resorption rate of the bone graft.

MATERIALS AND METHODS

Sixteen patients with unilateral alveolar clefts were treated. The control group received bone grafts without PRF, while the remaining patients comprised the PRF group and received grafts with PRF. Postoperative bone graft density and rate of bone resorption were assessed by CBCT at 1 month and 6 months after surgery.

RESULTS

Satisfactory bone bridging formation was observed in all patients and the mean of bone resorption in PRF group within 6 months after surgery lower than control group. The bone density of the PRF group was lower than that of the control group at 1st month, which later after 6 months increased to be more than the control group.

CONCLUSIONS

Platelet rich fibrin that mixed with autogenous bone graft was significantly reduce postoperative bone resorption. PRF may provide a higher bone density in the long postoperative course.

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.

Comparison of Two Methods for Presurgical Volumetric Evaluation of Alveolar Cleft Bone Defects Using Computer-Aided Engineering

ABSTRACT

Precise volumetric evaluation of the alveolar cleft facilitates accurate preparation of bone substitutes and reduces donor site morbidity. This study investigates 2 advanced presurgical volumetric assessment methods that use computer-aided engineering (CAE) software. Preoperative computed tomography (CT) scans from 20 unilateral alveolar cleft patients undergoing secondary alveolar bone grafting (SABG) were analyzed by CAE software. Cleft defect volumes were calculated using the mirror-reversed technique and the subtraction method. The mirror-reversed technique determines defect volume by reversing the noncleft side to the cleft side. The subtraction method determines defect volume by subtracting a mask of the preoperative cleft from a mask generated after simulated cleft filling. The mean defect volumes and calculation times of the mirror-reversed technique (1.27 ± 0.35 cm3; 11.80 ± 1.79 seconds) and the subtractive method (1.23 ± 0.32 cm3; 9.43 ± 1.35 seconds) did not differ significantly. In Bland-Altman analysis the 2 methods were equivalent for alveolar cleft defect assessment. Both methods exhibited acceptable interobserver reliability, high precision, clinical convenience, time efficiency, and high reproducibility, and can serve as valuable tools for the planning and execution of SABG. The subtraction method has broader potential applicability and can simulate intraoperative bone grafting more effectively.

Reliability and Reproducibility of Landmark Identification in Unilateral Cleft Lip and Palate Patients: Digital Lateral Vis-A-Vis CBCT-Derived 3D Cephalograms

BACKGROUND

The aim of the retrospective observational study was to compare the precision of landmark identification and its reproducibility using cone beam computed tomography-derived 3D cephalograms and digital lateral cephalograms in unilateral cleft lip and palate patients.

METHODS

Cephalograms of thirty-one (31) North Indian children (18 boys and 13 girls) with a unilateral cleft lip and palate, who were recommended for orthodontic treatment, were selected. After a thorough analysis of peer-reviewed articles, 20 difficult-to-trace landmarks were selected, and their reliability and reproducibility were studied. These were subjected to landmark identification to evaluate interobserver variability; the coordinates for each point were traced separately by three different orthodontists (OB_A, OB_B, OB_C). Statistical analysis was performed using descriptive and inferential statistics with paired t-tests to compare the differences measured by the two methods. Real-scale data are presented in mean ± SD. A p-value less than 0.05 was considered as significant at a 95% confidence level.

RESULTS

When comparing, the plotting of points posterior nasal spine (PNS) (p < 0.05), anterior nasal spine (ANS) (p < 0.01), upper 1 root tip (p < 0.05), lower 1 root tip (p < 0.05), malare (p < 0.05), pyriforme (p < 0.05), porion (p < 0.01), and basion (p < 0.05) was statistically significant.

CONCLUSION

In patients with a cleft lip and palate, the interobserver identification of cephalometric landmarks was significantly more precise and reproducible with cone beam computed tomography -derived cephalograms vis-a-vis digital lateral cephalograms.

Intra- and Interobserver Reliability of Bone Volume Estimation Using OsiriX Software in Patients with Cleft Lip and Palate Using Cone Beam Computed Tomography

The objective of the current study was to evaluate intra- and interobserver bone volume measurements and effect of orientation on the reliability of bone volume evaluation in as-acquired vis-à-vis oriented cone beam computed tomography scans using Osirix software and possible correlation between gender, age, and bone volume required. For this, 31 cone beam computed tomography (CBCT) scans of 14 girls and 17 boys (aged 9–13) with unilateral cleft lip and/or palate who met the inclusion criteria were analyzed. Efficacy and reliability of third party software Osirix for bone volume calculation was assessed using as acquired and oriented volumes by three specialists (a radiologist, an orthodontist, and an oral maxillofacial surgeon). The dataset and readings were anonymized to prevent any bias. Two-way mixed model analysis on as-acquired and oriented observations exhibited intra-class coefficient (ICC) values ≥ 0.90. Wilcoxon signed rank test (p = 0.10) and Kruskal–Wallis ANOVA (p = 0.46) indicated that although a clinical difference in volume assessment was seen between as-acquired and oriented observations (inter-observer and intra-observer), it was statistically insignificant. Spearman’s bi-variate correlation analysis revealed a significant relation between the type (side) of cleft and bone volume required to fill the defect (p < 0.05). Although there was clinical difference in bone volume measurement by the three observers, it was insignificant statistically. Clefts on the left side in the patients had significantly more bone required than the right side, whereas age and gender had no relation with bone needed to fill the defect. OsiriX software provided good reliability in measurements of bone volume.

Skeletal and Dental Habilitation of Residual Alveolar and Maxillary Clefts

ABSTRACT

Management of residual clefts of the alveolus and maxilla requires the coordinated effort of multiple members of the craniofacial team including surgeon, orthodontist, and when teeth are hypoplastic or absent, the prosthodontist to achieve complete habilitation. Such cooperation among specialists begins early in the patient's life and continues through completion of care.Although numerous publications on this topic exist, few present definitive multidisciplinary reconstructive outcomes with longterm results. In this review paper, the authors present our comprehensive, multidisciplinary protocols, experience, and techniques as they have evolved with over 35 years of practice at our Craniofacial Center.Details of our updated protocols for each intervention and procedure, including our current thoughts on appropriate timing, follow up and advantages from the incorporation of current technologies are discussed. Close cooperation among specialists at all stages of care, the use of evolving technology, and adherence to, and modification where indicated, of time honored team protocols enables us to consistently achieve successful functional and esthetic outcomes, while minimizing complications.

CBCT in orthodontics: a systematic review on justification of CBCT in a paediatric population prior to orthodontic treatment

BACKGROUND

Taking into account radiation doses, safety, and protection, we highlighted the features in which cone-beam computed tomography (CBCT) can offer an advantage compared to the conventional two-dimensional imaging in paediatric dentistry before orthodontic treatment.

OBJECTIVE

The aim of this article was to conduct a systematic review to assess the diagnostic efficacy of CBCT in the paediatric population at a pre-orthodontic phase.

SEARCH METHODS

MEDLINE via PubMed was searched to identify all peer-reviewed articles potentially relevant to the review until 1 July 2018. Relevant publications were selected by two reviewers independently.

SELECTION CRITERIA

The literature selection for this systematic review was carried out according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement and was based on predetermined inclusion criteria.

DATA COLLECTION AND ANALYSIS

Data were collected on overall study characteristics and examination characteristics of the selected studies. Methodological quality of the selected studies was evaluated. Original studies were assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) tool. Thereafter, levels of evidence were obtained according to Grading of Recommendations Assessment, Development and Evaluation criteria.

RESULTS

As a result of the QUADAS assessment, a total of 37 articles were included in the protocol. Following a proper protocol, CBCT was regarded as a reliable tool for assessment and management of impacted canine and root fracture. It provided a better evaluation of normal and pathological condylar shape and volume. CBCT was a superior choice for pre-surgical diagnostic applications in cleft lip and/or palate over a medical computed tomography based on its lower radiation exposure, shorter investigation time, and low purchase costs.

CONCLUSIONS

CBCT is justified only in those cases where conventional radiography fails to provide a correct diagnosis of pathology. Therefore, it cannot be regarded as a standard method of diagnosis. CBCT imaging may also be justified when it positively affects treatment options or provides treatment optimization.

REGISTRATION

None.

CONFLICT OF INTEREST

None to declare.

Assessment of Bone Formation After Secondary Alveolar Bone Grafting With and Without Platelet-Rich Plasma Using Computer-Aided Engineering Techniques

The aim of this study was to analyze the newly formed bone volume (FV), 6 months after secondary alveoloplasty using iliac cancellous bone graft, with and without platelet-rich plasma (PRP). Forty patients with unilateral alveolar cleft were involved in this randomized, prospective, comparative study, with 20 patients each forming the control (group A) and PRP (group B) groups, respectively. The preoperative alveolar defect volume (DV) and the postoperative FV were automatically calculated by the computer-aided engineering software using the patients' pre and postsurgical computed tomography data. The volume of the actual bone graft (AV) was identical to the DV calculated before surgery. The bone formation ratio (BF%) was calculated as follows: BF% = (FV/AV) × 100%. The mean BF% was 42.54 ± 9.32% in group A and 46.97 ± 18.49% in group B. There was no statistically significant difference between the 2 groups for BF% (P > 0.05). The study presents a fast and accurate method for assessing the effect of PRP in alveolar grafting. However, the study found no conclusive evidence on the effect of PRP on bone growth.

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.

Comparative Volume Analysis of Alveolar Defects by 3D Simulation

A precise volumetric assessment of maxillary alveolar defects in patients with cleft lip and palate can reduce donor site morbidity or allow accurate preparation of bone substitutes in future applications. However, there is a lack of agreement regarding the optimal volumetric technique to adopt. This study measured the alveolar bone defects by using two cone-beam computed tomography (CBCT)-based surgical simulation methods. Presurgical CBCT scans from 32 patients with unilateral or bilateral clefts undergoing alveolar bone graft surgery were analyzed. Two hands-on CBCT-based volumetric measurement methods were compared: the 3D real-scale printed model-based surgical method and the virtual surgical method. Different densities of CBCT were compared. Intra- and inter-examiner reliability was assessed. For patients with unilateral clefts, the average alveolar defect volumes were 1.09 ± 0.24 and 1.09 ± 0.25 mL (p > 0.05) for 3D printing- and virtual-based models, respectively; for patients with bilateral clefts, they were 2.05 ± 0.22 and 2.02 ± 0.27 mL (p > 0.05), respectively. Bland–Altman analysis revealed that the methods were equivalent for unilateral and bilateral alveolar cleft defect assessment. No significant differences or linear relationships were observed between adjacent different densities of CBCT for model production to obtain the measured volumes. Intra- and inter-examiner reliability was moderate to good (intraclass correlation coefficient (ICC) > 0.6) for all measurements. This study revealed that the volume of unilateral and bilateral alveolar cleft defects can be equally quantified by 3D-printed and virtual surgical simulation methods and provides alveolar defect-specific volumes which can serve as a reference for planning and execution of alveolar bone graft surgery.

Changes in alveolar process dimensions following extraction of molars with advanced periodontal disease: A clinical pilot study

OBJECTIVE

To use cone beam computed tomography (CBCT) to assess the alterations of socket dimensions after a 6-month healing period following molar extraction.

MATERIALS AND METHODS

Seventeen molars were extracted due to advanced periodontitis. CBCT scans were taken immediately after extraction and once more 6 months later. Superimposition of CBCT images was used to measure the following: horizontal changes at extraction sites at three corono-apical levels (-1, -3, and -5 mm) below the bone crest, three mesio-distal levels (mesial, central, and distal), vertical changes at nine regions of the alveolar crest, and alveolar bone volume.

RESULTS

The width of the central crests at -1 mm decreased by 0.59 and 0.72 mm in the buccal and 0.27 and 0.02 mm in the lingual, in the maxilla and mandible, respectively. No statistically significant decreases in the ridge height were observed except in the disto-palatal region with a 1.11 mm decrease in the maxilla (p < 0.05). Heights of the buccal and lingual bone plates decreased significantly and ranged from 0.56 to 1.38 mm in the mandible after 6 months of healing (p < 0.05). Overall, ridge height changes were not significantly different between the maxilla and mandible (p > 0.05) and no significant volumetric bone loss occurred in either maxillary or mandibular sockets after 6 months of healing.

CONCLUSIONS

Socket dimensions of molars with advanced periodontal disease showed a significant increase at the middle-central portion, although there were no significant changes of horizontal width 6 months following the procedures.

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 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.

Autogenous Bone Graft Versus Bovine Bone Graft in Association With Platelet-Rich Plasma for the Reconstruction of Alveolar Clefts: A Pilot Study

Objective:

To compare the outcomes of 2 different bone graft materials: autogenous bone grafts from mandibular symphysis and bovine bone grafts associated with platelet-rich plasma (PRP).

Methods:

Twenty individuals met the inclusion criteria and accepted to participate in the study. Group A patients underwent alveolar bone grafting using autologous bone and group B patients using a bovine bone graft associated with PRP. Cone beam computed tomography scans were taken and reconstructed 3-dimensionally for all patients preoperatively and 1 year postoperatively.

Results:

A significant reduction was detected for area and volume within group A and group B. Between groups, no significant difference was found for area or volume.

Conclusions:

Bovine grafts associated with PRP are a good option for the reconstruction of alveolar clefts and provide good results such as autologous bone grafts.

Three-dimensional analysis of bone remodeling following ridge augmentation of compromised extraction sockets in periodontitis patients: A randomized controlled study

OBJECTIVES

The aim of this study was to analyze linear and volumetric hard tissue changes in severely resorbed alveolar sockets after ridge augmentation procedure and to compare them with spontaneous healing using three-dimensional cone beam computed tomography (CBCT).

MATERIAL AND METHODS

Thirty patients (mean age 53.2 ± 6.3 years) requiring tooth extraction for advanced periodontitis were randomly allocated to test and control groups. The test sites were grafted using a collagenated bovine-derived bone (DBBM-C) covered with a collagen membrane, while control sites had spontaneous healing. Both groups healed by secondary intention. Linear and volumetric measurements were taken on superimposed CBCT images obtained after tooth extraction and 12 months later.

RESULTS

Greater horizontal shrinkage, localized mainly in the crestal zone, was observed in the control group (4.92 ± 2.45 mm) compared to the test group (2.60 ± 1.24 mm). While both groups presented a rebuilding of the buccal wall, it was most pronounced in the grafted sockets (2.50 ± 2.12 mm vs. 0.51 ± 1.02 mm). A significant difference was also registered in the percentage of volume loss between grafted and non-grafted sites (9.14% vs. 35.16%, p-value <.0001).

CONCLUSION

Alveolar sockets with extensive buccal bone deficiencies undergo significant three-dimensional volumetric alterations following natural healing. The immediate application of a slow-resorbing xenograft with a covering collagen membrane seems to be effective in improving alveolar ridge shape and dimensions, thus potentially reducing the need for adjunctive regenerative procedures at the time of implant placement.

Mesial and distal alveolar bone morphology in maxillary canines moved into the grafted alveolar cleft: Computed tomography evaluation

INTRODUCTION

The aims of this study were to qualitatively assess the mesial and distal alveolar bone of maxillary canines mesially moved to replace absent lateral incisors in patients with unilateral cleft lip and palate after secondary alveolar bone graft and to assess the reproducibility of the proposed cone-beam computed tomography (CBCT) method.

METHODS

The sample comprised CBCT examinations of 30 patients with unilateral cleft lip and palate from 1 center. CBCT images were taken at least 6 months after comprehensive orthodontic treatment. The noncleft side was used as the control group. Using axial sections, scores from 0 to 4 (bone absence to complete bone filling, respectively) were given to the mesial and distal alveolar bones of the maxillary canines. Interexaminer and intraexaminer reproducibility was assessed using kappa statistics. Intergroup comparisons were performed using Wilcoxon tests.

RESULTS

Interexaminer and intraexaminer agreement was excellent. Intergroup comparison identified smaller scores at the cervical and middle root levels of the cleft side mesial alveolar bone of the maxillary canines. At the cleft side, 85 mesial sites showed favorable scores (3 or 4); 1 had a score of 1, and 4 had scores of 2. At the distal surface, 78 sites were evaluated, and only 1 site received a score of 1. The noncleft side had scores of 4 for all sites.

CONCLUSIONS

The new CBCT scale showed good reproducibility. CBCT axial sections are reliable for a qualitative appraisal of alveolar bone in a grafted alveolar cleft. Mesial bone defects can be observed in maxillary canines moved into grafted areas after comprehensive orthodontic treatment, especially at the cervical root half.

Analyzing the teeth next to the alveolar cleft: Examination and treatment proposal prior to bone grafting based on three-dimensional versus two-dimensional diagnosis-A diagnostic study

PURPOSE

The objective was to evaluate the diagnostic and prognostic value of three-dimensional (3D) cone beam computed tomography (CBCT) on information about the cleft and alignment of cleft neighboring teeth.

MATERIALS AND METHODS

Panoramic X-rays, small-volume CBCTs, and study casts of 20 patients with a total of 22 alveolar clefts were analyzed prior to secondary bone grafting. Six maxillofacial surgeons and 6 orthodontists rated the following parameters: visibility of alveolar cleft expansion, position and probability of alignment of cleft neighbored teeth. Two-dimensional (2D) X-rays and casts were rated first; CBCT and casts followed at least 4 weeks later. Radiologic bone height in the region of the former alveolar cleft, as well as alignment and reasons for nonalignment of cleft neighbored teeth, were recorded 4 years later.

RESULTS

The rate of proper proposals regarding the real treatment outcome using 2D- or 3D-material did not differ statistically. Although 5%-45% of the proposals were changed when using 3D instead of 2D records, Fleiss multirater kappas showed no essential differences. Raters' profession and experience had no influence on the rate of correct proposals.

CONCLUSION

In orthodontics, small-volume CBCT may be justified only as supplement to a routine panoramic X-ray, and only in selected cases or for surgical preparation.

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.

A novel semi-automatic segmentation protocol for volumetric assessment of alveolar cleft grafting procedures

A novel protocol for volumetric assessment of alveolar cleft grafting procedures is presented. Eleven cone-beam computed tomography (CBCT) datasets of patients who underwent secondary alveolar cleft reconstructive surgery for a unilateral alveolar cleft were evaluated by two investigators. Residual bone volumes 1 year after surgery were analysed using a semi-automated technique in which preoperative CBCT datasets were superimposed on the postoperative scans using voxel-based registration. To define the correct boundaries of the alveolar cleft defect in the preoperative CBCT dataset, a mirror image of the preoperative CBCT dataset was superimposed on the preoperative CBCT dataset. For the difference in residual bone volume between the two observers, an intraclass correlation of 0.98 and a Dice coefficient of 0.89 were found. This study describes a reliable segmentation protocol for volumetric analysis of the alveolar cleft defect in patients with a unilateral alveolar cleft.

Osteogenesis effect of guided bone regeneration combined with alveolar cleft grafting: assessment by cone beam computed tomography

Cone beam computed tomography (CBCT) allows for a significantly lower radiation dose than conventional computed tomography (CT) scans and provides accurate images of the alveolar cleft area. The osteogenic effect of guided bone regeneration (GBR) vs. conventional alveolar bone grafting alone for alveolar cleft defects was evaluated in this study. Sixty alveolar cleft patients were divided randomly into two groups. One group underwent GBR using acellular dermal matrix film combined with alveolar bone grafting using iliac crest bone grafts (GBR group), while the other group underwent alveolar bone grafting only (non-GBR group). CBCT images were obtained at 1 week and at 3 months following the procedure. Using Simplant 11.04 software, the bone resorption rate was calculated and compared between the two groups. The bone resorption rate from 1 week to 3 months following bone grafting without the GBR technique was 36.50±5.04%, whereas the bone resorption rate using the GBR technique was 31.69±5.50% (P=0.017). The application of autogenous iliac bone combined with the GBR technique for alveolar bone grafting of alveolar cleft patients can reduce bone resorption and result in better osteogenesis.

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

OBJECTIVE

The aims of this retrospective study were to evaluate the volumetric outcome of mandibular symphyseal bone graft in patients with unilateral cleft lip and palate by estimating the bone fill 1-year postoperatively on cone beam computed tomography. The outcome was assessed in relation to the (1) root development stage of the cleft side canine, (2) presence/absence of a cleft side lateral incisor, and (3) volume size of the preoperative cleft defect.

METHODS

The alveolar bone defect volume of 32 consecutive unilateral cleft lip and palate patients aged 8 years 1 month to 11 years 11 months was evaluated using a recently defined and standardized protocol. The outcome was calculated as the percentage of bone fill using the formula (VOLpre - VOLpost) / VOLpre) × 100.

RESULTS

The preoperative mean alveolar cleft volume was 934 mm(3), and the average percentage bone fill was 87%. There was no significant difference between bone fill and root developmental stage of the cleft-side canine (P = .882) nor presence/absence of the cleft side lateral incisor (P = .803). The size of the cleft defect did not correlate with the bone fill (r = .03, P = .84).

CONCLUSIONS

Secondary alveolar bone grafting with mandibular symphyseal bone graft in patients with unilateral cleft lip and palate is an attractive procedure assessed from the volumetric outcome using cone beam computed tomography. The 1-year average bone fill of 87% was not significantly influenced by root development stage of the cleft-side canine, presence or the absence of a cleft side lateral incisor, or size of the alveolar defect.