Computed tomography of alveolar bone grafts 20 years after repair of unilateral cleft lip and palate

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.

Mechanical Tension-Stress in Alveolar Cleft Repaired With Autogenous Bone in Canine Models

OBJECTIVE

Cleft lip and/or palate is a common birth defect worldwide, always accompanied by alveolar cleft. However, the success rate of secondary alveolar bone grafting is unsatisfactory. Rapid maxillary expansion (RME) often used after bone transplantation provides functional stimulation for bone graft area. This study aimed to investigate the effect of RME force on the bone graft area and midpalatal suture, and screen out the most suitable loaded force and loaded teeth, so as to provide a reference for clinical treatment.

METHODS

Fourteen 24-week-old male beagles were assigned randomly to 3 groups: blank control, autogenous, and autogenous with RME. Three-dimensional finite element analysis was conducted to evaluate the distribution and value of the stress in the model. The maxillae were collected and subjected to radiography and helical computed tomography to evaluate new bone formation in the graft area. Van Gieson's Picrofuchsin staining was performed for histomorphological observation.

RESULTS

After 8 weeks of RME treatment, new bone formation of the dogs was markedly accelerated, and bone resorption was significantly reduced compared with the untreated dogs or those only treated with autogenous iliac bone. The treatment with RME evidently made the bone trabecula more abundant and the area of bone formation larger. Three-dimensional finite element analysis showed that the clinical effect can be achieved by using canine teeth as the loaded teeth and applying force of 10 MPa.

CONCLUSION

Rapid maxillary expansion after bone grafting had a positive effect on osteogenesis in a canine model of alveolar cleft.

Alveolar cleft bone grafting: factors affecting case prognosis

Objectives

The goal of this retrospective study was to determine the significance and impact of several factors on the alveolar cleft bone grafting procedure.

Materials and Methods

The medical records were reviewed. In addition, x-rays were checked. The size of every cleft was measured in this retrospective study. The analyzed factors included sex, age, type of cleft, size of the cleft, and the type of flap used in surgery. The patients were characterized into group A (no complications, Bergland scale 1 or 2), group B (complications or Bergland scale 3), or group C (failure cases). Statistical analysis was performed with a P-value set at 0.05.

Results

There were 32 cases in group A, 26 in group B, and 9 in group C. Multinomial logistic regression showed an association between the type of the cleft and the size of the cleft, with the presence of complications, or achieving type 3 on the Bergland scale, with odds ratios of 5.118 and 6.000, respectively. The type of cleft was related to failure with an odds ratio of 4.833. Given a small sample, statistical analysis could not be performed to evaluate the relationship between the size of the cleft and group C. Age, sex, and the type of the flap were not significant factors.

Conclusion

The cleft size of more than 10 mm and bilateral clefts were listed regarding their effect on the procedure. Clinicians should not overlook these factors. In addition, patients must be informed of any risks that are present.

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.

Eighteen-Year Follow-Up of 160 Consecutive Individuals Born With Unilateral Cleft Lip or Cleft Lip and Alveolus Treated by the Oslo Cleft Lip and Palate Team

OBJECTIVE

Describe patients born with unilateral cleft lip with or without cleft alveolus (CL±A) in relation to cleft severity and laterality, gender, associated anomalies and syndromes, number and type of lip- and nose operations, and time of alveolar bone graft (ABG) treatment in relation to dental status in cleft area.

MATERIALS AND METHODS

Patients included 220 children born with unilateral CL±A, born between 1988 and 1997 referred to the Oslo Cleft Lip and Palate Team. The data were collected retrospectively. All patients were followed up until 18 years of age.

RESULTS

Among all CL±A, 3.6% had recognized syndromes, 6.8% had associated anomalies, and in 89.6% CL±A was the only malformation. CL±A was more common, but not more severe, on the left side. Among the 160 individuals with CL±A without syndromes and associated anomalies, 66.9% had an isolated soft tissue CL, and 33.1% were diagnosed with a CL alveolus (CL+A). Male predominance was observed. Children with CL+A had more severe soft tissue clefts of the lip and underwent more lip and nose surgeries than children born with CL. The time of ABG was found to be at a younger age when the patient had a lateral incisor in the cleft area than when this tooth was missing.

CONCLUSION

Findings provide a reference for morphologic variations in CL±A, and insight into the surgical burden of care until the age of 18 years.

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Premaxillary Osteotomy and Guided Tissue Regeneration in Secondary Bone Grafting in Children with Bilateral Cleft Lip and Palate

Objective:

To introduce a surgical technique for secondary alveolar bone grafting performed in conjunction with premaxillary osteotomy and guided tissue regeneration in children with bilateral clefts. This paper also looks at the outcomes of this surgery in a series of 15 consecutive patients.

Methods:

Secondary alveolar bone grafting (with a premaxillary osteotomy and guided tissue regeneration with a collagen membrane) is usually carried out in the mixed dentition stage. This retrospective study used patients’ medical records, radiographs, and clinical examination to assess the outcome of the surgery. Patients were followed up for an average of 3 years.

Results:

Bone grafting was successful in all cases. No premaxillae were lost and there was no long-term morbidity of the donor site. Radiographic assessment of the bone heights showed an average of 94% retention, 3 months postoperatively. Preliminary assessment of maxillary canine eruption is encouraging, with 79% being fully erupted in those patients who are at least 3 years post–bone grafting.

Conclusion:

Premaxillary osteotomy allows repositioning of the premaxilla to its optimal preplanned position and successful closure of all fistulae. We have found that use of a collagen membrane is a useful adjunct.

Quantitative evaluation of maxillary alveolar cortical bone thickness and density using computed tomography imaging

INTRODUCTION

Primary stability is essential to the success of orthodontic mini-implants (OMIs) and heavily depends on the mechanical retention between OMIs and their supporting bone. Alveolar cortical bone commonly serves as the supporting bone for OMIs during treatment. The purposes of this study were to characterize alveolar cortical bone thickness and density in the maxilla and to explore patient factors that may significantly affect these bone properties.

METHODS

Sixty medical computed tomography scans of the maxilla were analyzed from a selected sample of patients seen at the Radiology Department of Boston Children's Hospital. Interradicular alveolar bone thickness and density were measured at 2, 4, 6, and 8 mm from the buccal and palatal alveolar bone crests using the Synapse 3D software (version 4.1; FUJIFILM Medical Systems USA, Stamford, Conn). Analyses were conducted with STATA /1C (version 12.0 for Windows; StataCorp, College Station, Tex) using multivariate mixed-effects regression models and paired t tests.

RESULTS

Mean age and body mass index of the study sample were 17.88 years and 22.94 kg/m², respectively. Cortical bone density and thickness significantly increased from the coronal (2 mm) to the apical (8 mm) regions of the alveolar bone (P <0.05). At 8 mm from the alveolar crest, interradicular buccal cortical bone was thickest (1 mm) and densest (1395 Hounsfield units) between the first and second molars. On the palatal side, the thickest bone (1.15 mm) was found between the canine and first premolar; it was similarly densest (1406 Hounsfield units) between the first premolar and canine, and between the first premolar and second premolar interradicular bones. On average, palatal cortical bone was thicker and denser compared with buccal; this difference was statistically significant (P <0.01) in the anterior and middle maxilla, with the anterior maxillary region showing the greatest difference. Female subjects have significantly denser bone compared with male subjects; however, sex is not significantly associated with bone thickness. Body mass index and age are positively associated with bone thickness and density. Radiologic absence of bone was more commonly seen in the anterior maxilla.

CONCLUSIONS

Alveolar bone properties vary in the maxilla in patterns that could guide clinicians in selecting sites best suited for placement of OMIs.

Long-Term Computed Tomographic Evaluation of Alveolar Bone Formation in Patients with Unilateral Cleft Lip and Palate after Early Secondary Gingivoalveoloplasty

BACKGROUND

The goal of this study was to evaluate with a three-dimensional method the long-term quality of alveolar ossification in unilateral cleft lip and palate patients who underwent early secondary gingivoalveoloplasty according to the Milan surgical protocol.

METHODS

The sample consisted of 63 computed tomographic scans of unilateral cleft lip and palate patients in permanent dentition. The average age at the time of assessment was 15.7 years. Alveolar thickness, nasoalveolar height, nasal floor ossification, and hard palate morphology were evaluated using dental, axial, and coronal cuts on computed tomographic scans and three-dimensional models. All measurements were normalized and ratios of the affected side versus the nonaffected side were provided. Volume measurements and ratios of each hemimaxilla were added. The presence or absence of the permanent lateral incisor on the cleft side was also recorded.

RESULTS

Alveolar thickness and height were ideal or good, respectively, in 89.5 and 91.4 percent of the sample. Insufficient ossification (<25 percent) was found in three patients (5.2 percent), and only one of them (1.7 percent) presented no bone bridging. A statistically significant association was detected between the degree of alveolar ossification, the type of nasal floor ossification, and volume ratio.

CONCLUSIONS

Early secondary gingivoalveoloplasty seemed to allow an adequate ossification of both the alveolar and nasal region. Three-dimensional evaluation of the alveolar cleft ossification provided further information on alveolar bridging and allowed evaluation of the bone availability for implant placement.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Repair of cleft alveolar bone with bioactive glass material using Z-plasty flap

Multiple literature addresses cleft alveolar bone, with little consensus on the preferred surgical technique. Hence, we described a transoral approach for repair of cleft alveolar bone with Z-plasty and using bioactive glass.

STUDY DESIGN

Case presentation and surgical technique description. In conclusion, transoral mucosal repair cleft alveolar bone Z-plasty using bioactive glass demonstrated an alternative easy and simple approach for augmentation of unilateral alveolar cleft patients.

Tomographic Assessment of Bone Formation After the Collares Technique of Gingivoperiosteoplasty in Patients With Cleft Lip and Palate

OBJECTIVES

This cross-sectional study sought to assess bone formation and spontaneous tooth eruption in a cohort of 25 consecutive patients aged 6 to 11 years who underwent primary gingivoperiosteoplasty by the Collares technique.

DESIGN

Cross-sectional study assessing bone formation in the cleft area using a within-group time series design.

SETTING

Hospital de Clínicas de Porto Alegre (HCPA), a tertiary hospital in Brazil.

PATIENTS

Twenty-five patients with nonsyndromic, complete unilateral cleft lip and palate, no comorbidities, and unerupted permanent canines.

INTERVENTION

Cheiloplasty was performed by means of the Millard II technique, with the addition of a triangle at the mucocutaneous junction, vomer flap nasal floor closure, and wide subperiosteal elevation, followed by gingivoperiosteoplasty by the Collares technique.

MAIN OUTCOME MEASURES

Cone-beam computed tomography was used to assess treatment effect. In a novel method, software was used to obtain two three-dimensional reconstructions, one each of the cleft and noncleft sides, enabling quantitative comparison of bone presence in the alveolar defect area.

RESULTS

Of the 25 patients, 24 achieved bone bridge formation. The cleft side had 75.1% (67.9%-82.3%) of the bone volume, 70.5% (53.1%-87.9%) of the height, and 63.3% (44.1%-82.5%) of the width of the noncleft side. Bone formation was 17.28% lower in patients with lateral incisor agenesis.

CONCLUSION

Collares gingivoperiosteoplasty performed well as a technique for alveolar repair in patients with cleft lip and palate, allowing spontaneous eruption of deciduous and permanent lateral incisors through the bone bridge created.

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.

Three-dimensional imaging methods for quantitative analysis of facial soft tissues and skeletal morphology in patients with orofacial clefts: a systematic review

Background

Current guidelines for evaluating cleft palate treatments are mostly based on two-dimensional (2D) evaluation, but three-dimensional (3D) imaging methods to assess treatment outcome are steadily rising.

Objective

To identify 3D imaging methods for quantitative assessment of soft tissue and skeletal morphology in patients with cleft lip and palate.

Data sources

Literature was searched using PubMed (1948–2012), EMBASE (1980–2012), Scopus (2004–2012), Web of Science (1945–2012), and the Cochrane Library. The last search was performed September 30, 2012. Reference lists were hand searched for potentially eligible studies. There was no language restriction.

Study selection

We included publications using 3D imaging techniques to assess facial soft tissue or skeletal morphology in patients older than 5 years with a cleft lip with/or without cleft palate. We reviewed studies involving the facial region when at least 10 subjects in the sample size had at least one cleft type. Only primary publications were included.

Data extraction

Independent extraction of data and quality assessments were performed by two observers.

Results

Five hundred full text publications were retrieved, 144 met the inclusion criteria, with 63 high quality studies. There were differences in study designs, topics studied, patient characteristics, and success measurements; therefore, only a systematic review could be conducted. Main 3D-techniques that are used in cleft lip and palate patients are CT, CBCT, MRI, stereophotogrammetry, and laser surface scanning. These techniques are mainly used for soft tissue analysis, evaluation of bone grafting, and changes in the craniofacial skeleton. Digital dental casts are used to evaluate treatment and changes over time.

Conclusion

Available evidence implies that 3D imaging methods can be used for documentation of CLP patients. No data are available yet showing that 3D methods are more informative than conventional 2D methods. Further research is warranted to elucidate it.

Systematic review registration

International Prospective Register of Systematic Reviews, PROSPERO CRD42012002041

Use of three-dimensional computed tomography to classify filling of alveolar bone grafting

Several authors have proposed classifications to analyze the quality over time of secondary alveolar bone grafting. However, little discussion has been held to quantitatively measure the secondary bone grafting for correction of nasal deformity associated to cleft palate and lip. Twenty patients with unilateral alveolar cleft, who underwent secondary alveolar bone grafting, were studied with 3D computer tomography. The height between the inferior portion of the pyriform aperture and the incisal border of the unaffected side (height A) and the affected side (height B) was measured using a software Mirror. A percentage was then obtained dividing the height B by the height A and classified into grades I, II, and III if the value was greater than 67%, between 34% and 66%, or less than 33%. Age, time of followup, initial operation, and age of canine eruption were also recorded. All patients presented appropriate occlusion and function. Mean time of followup was 7 years, and mean initial age for operation was 10 years old. 16 patients were rated as grade I and 4 patients as grade II. No cases had grade III. We present a new grading system that can be used to assess the success of secondary bone grafting in patients who underwent alveolar cleft repair.

Evaluation of maxillary alveolar reconstruction using a resorbable collagen sponge with recombinant human bone morphogenetic protein-2 in cleft lip and palate patients

INTRODUCTION

A resorbable collagen matrix with recombinant human bone morphogenetic protein (rhBMP-2) was compared with traditional iliac crest bone graft for the closure of alveolar defects during secondary dental eruption.

METHODS

Sixteen patients with unilateral cleft lip and palate, aged 8 to 12 years, were selected and randomly assigned to group 1 (rhBMP-2) or group 2 (iliac crest bone graft). Computed tomography was performed to assess both groups preoperatively and at months 6 and 12 postoperatively. Bone height and defect volume were calculated through Osirix Dicom Viewer (Pixmeo, Apple Inc.). Overall morbidity was recorded.

RESULTS

Preoperative and follow-up examinations revealed progressive alveolar bone union in all patients. For group 1, final completion of the defect with a 65.0% mean bone height was detected 12 months postoperatively. For group 2, final completion of the defect with an 83.8% mean bone height was detected 6 months postoperatively. Dental eruption routinely occurred in both groups. Clinical complications included significant swelling in three group 1 patients (37.5%) and significant donor-site pain in seven group 2 patients (87.5%).

CONCLUSIONS

For this select group of patients with immature skeleton, rhBMP-2 therapy resulted in satisfactory bone healing and reduced morbidity compared with traditional iliac crest bone grafting.

Craniofacial computerized tomography analysis of the midface of patients with repaired complete unilateral cleft lip and palate

INTRODUCTION

Computerized tomography (CT) makes regional anatomy available as a series of cross-sectional axial images that can be analyzed unobstructed by other anatomic features. In this study, we aimed to analyze the maxillary dentoalveolar and deeper structures in patients with surgically repaired complete unilateral cleft lip and palate (CLP) and to investigate whether significant asymmetry existed in the deeper midfacial structures, using axial CT.

METHODS

Axial CT scans of 15 children (7 boys, 8 girls; mean age, 11.59 +/- 1.34 years) with repaired complete unilateral CLP were acquired parallel to Reid's base line. Specific landmarks applicable for CT were defined and plotted to undertake a comprehensive Craniofacial CT Analysis of the midface. Twenty-six pairs of transverse and sagittal measurements made to a cranial base midsagittal construct and interspinosum fit line, respectively, were compared by using the paired t test.

RESULTS

Significant reduction of 19.05% in the nasal chamber width (2.54 +/- 1.49 mm; P <0.001), more distal position of the bony alar base (2.28 +/- 1.71 mm; P <0.001), and the sagittal position of the most prominent anterolateral point on the maxillary alveolar process (1.62 +/- 1.85 mm; P <0.01) were noted on the cleft side. The lower half of the bony nasal septum was consistently deviated toward the cleft side, and the nasal tip was deviated to the noncleft side in 60% of the subjects. The anterior nasal spine was deviated to the noncleft side in 73.3% of the subjects and a mean deviation of the anterior nasal spine of 2.84 +/- 3.90 mm toward the noncleft side was measured. Significant sagittal and transverse asymmetry in deeper midfacial regions was not observed. Unilateral dental-arch collapse was observed in 73.3% of the sample, bilateral collapse in 20%, and no collapse in 6.7%. The soft-tissue support of the alveolar margins of the cleft did not show significant differences between the cleft and noncleft sides.

CONCLUSIONS

CT is an excellent method for quantifying surface and deep craniofacial structures. Most asymmetries and deformities in the 10- to 14-year-old patients with repaired complete unilateral CLP we studied were in the dentoalveolar area near the cleft and the nasal chamber and not in the deeper regions of the maxillary complex.

Outcome of secondary alveolar bone grafting before and after eruption of the canine in Jordanian patients with cleft lip and palate

This prospective study was carried out at the Cleft Lip and Palate Centre at King Abdullah University Hospital and Maxillofacial Unit at Jordan University of Science and Technology during the period of 2000 to 2006. The sample consisted of 77 secondary alveolar bone grafts (62 patients), which were performed according to the same standardized surgical technique by a single maxillofacial surgeon. The objective was to assess the outcome of secondary alveolar bone grafting (SABG) before (early SABG) and after (late SABG) the eruption of the permanent maxillary canine in unilateral and bilateral Jordanian cleft subjects. Patients were divided into four groups: early unilateral SABG (22), late unilateral SABG (25), early bilateral SABG (8), and late bilateral SABG (7). Follow-up period ranged from 6 months to 5 years. Periapical or occlusal radiographs were used to assess the outcome of SABG. The degree of bony fill in the cleft area was assessed using the 4-point Kindelan scale. Only Grade 1 (more than 75% bony fill) cases were considered successful. Early unilateral SABG had a success rate of 90% while late unilateral SABG rate was 80%. The overall success rate of the unilateral SABG (85%) was higher than the rate for the bilateral cases (56%). Our findings support the conclusion that the outcome of early SABG is superior to late SABG. The overall success rate of SABG sample (74%) compared relatively well with other published results.