Orthodontie Treatment Results following Grafting Autologous Mandibular Bone to the Alveolar Cleft in Patients with a Complete Unilateral Cleft

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Incidence of complications in secondary alveolar bone grafting of bilateral clefts with premaxillary osteotomy: a retrospective cohort study

OBJECTIVE

To evaluate factors affecting incidence of complications after secondary alveolar bone grafting with premaxillary osteotomy (SABG + PO) in children with complete bilateral cleft of lip and palate (BCLP).

MATERIALS AND METHODS

Data were collected from children with BCLP treated with SABG + PO from 2004 to 2014 at our institute. Preoperative parameters included age, donor site, race, gingival health, bone quality around cleft-related teeth, premaxilla position, graft timing, presence of canines in the cleft, and presence of deciduous teeth around the cleft area. Logistic regression and the chi-squared test were used to assess correlations and the incidence of complications.

RESULTS

In the 64 patients, a significant correlation was found between complication rate and timing of bone grafting with respect to early versus late SABG + PO (p = 0.041), age > 12 years (p = 0.011; odds ratio (OR) 5.9; 95% confidence interval (CI) 1.49-23.93), malposition of the premaxilla (p = 0.042; OR 3.3; 95% CI 1.04-10.13), and preoperative bone quality around cleft-related teeth (p = 0.005; OR 5.3; 95% CI 1.6-17.2).

CONCLUSIONS

The timing of SABG + PO is essential, as early SABG + PO is associated with fewer complications. A malpositioned premaxilla and poor bone quality around cleft-related teeth are associated with more complications. Therefore, preoperative orthodontic repositioning of the malpositioned premaxilla before SABG + PO should be considered.

CLINICAL RELEVANCE

Analysis of treatment protocols and complications for BCLP patients underscores that proper timing of SABG + PO and correct premaxilla repositioning help reduce complications.

Study on Tooth Movement After the Alveolar Bone Grafting in Patients With Unilateral Cleft Lip and Palate

OBJECTIVES

The aim of the study was to explore the effectiveness of the cleft-adjacent teeth moved into the grafted alveolar bone in unilateral cleft lip and palate (UCLP) patients, and to evaluate the alveolar bone support of the teeth.

METHODS

Twenty unilateral cleft lip and palate patients were recruited in this study. The average age was 12 years and 8 months. Periapical radiographs were taken for the cleft-adjacent teeth 3 months after bone grafting (T1) and after teeth moving into the grafted bone (T2), and for the contralateral teeth (T3) when teeth aligned. Alveolar bone support of the moved teeth and the contralateral teeth were measured using the ratio of bone support height to root length. Paired t test was performed for statistical analysis with SPSS17.0 software package.

RESULTS

All the cleft-adjacent teeth were bodily moved into the grafted area. Average alveolar bone support ratio for the moved teeth was 86.48% (T1), 87.11% (T2), and 90.81% (T3) for the contralateral teeth. There was no statistically significant difference between T1 and T2 (P > 0.05). Although the contralateral teeth had the highest alveolar bone support ratio, significant differences were found between T3 and T2 (P < 0.05).

CONCLUSIONS

Cleft-adjacent teeth could be bodily moved into the grafted bone from the iliac crest in UCLP patients. A successful level of alveolar bone support for the moved teeth was achieved. Moved-in teeth could be functionally loaded and may be benefit to the reduction of the resorption of grafted bone.

A Prospective Study of Chin Bone Graft Harvesting for Unilateral Maxillary Alveolar Cleft During Mixed Dentition

PURPOSE

The chin is a common donor site for alveolar cleft bone grafting. The amount of bone available at this site can be limited, because conservative harvesting with mixed dentition must consider the incisive nerve, the unerupted mandibular canine, and the integrity of the inferior mandibular border.

MATERIALS AND METHODS

Patients with nonsyndromic unilateral alveolar cleft in the mixed dentition stage were selected for this study. The volume of bone obtained from the mandibular symphysis (symphysis menti), degree of alteration in lower lip sensation, anterior tooth vitality, remaining bone in the alveolar cleft, and bone defects at the donor site 1 year after surgery were evaluated.

RESULTS

Eighteen patients were enrolled in this study. The mean volume of bone harvested from the symphysis was 2.1 mL (range, 1.6 to 2.3 mL). For all cases, the bone volume harvested from the symphysis was insufficient to fill the alveolar cleft defect, and allograft had to be added to completely fill the cleft. Allograft was admixed in the range of 0.5 to 1 mL with autogenous bone harvested from the mandible. Lower lip sensation and vitality of the anterior teeth of the mandible were within the normal range 1 year after surgery in all cases. Fourteen of 18 patients (77.8%) had normal bone height or bone height at least three fourths of the expected height in the grafted alveolar cleft after 1 year; only 10% of the defect remained in the mandible.

CONCLUSION

The amount of bone yielded by conservative monocortical bone harvest from the mandibular symphysis during the mixed dentition stage for unilateral alveolar cleft bone grafting is not sufficient in volume and should be mixed with allograft. However, donor site morbidity is low with this approach.

Evaluation of Bone Height and Bone Mineral Density Using Cone Beam Computed Tomography After Secondary Bone Graft in Alveolar Cleft

The purpose of this study was to assess the optimal timing of subsequent dental implant placement and orthodontics after alveolar bone grafting (ABG) in patients with unilateral complete clefts of the alveolar process. Iliac bone graft surgery was performed on 60 patients. Bone mineral density (BMD) and height of the ABG areas were assessed using cone beam computed tomography at 3 and 6 months postoperatively. The heights of the labial and palatal bone graft areas were classified using the modified Bergland classification. The study found that there was no change in BMD between 3 months (mean ± SD: 406.51 ± 71.28 Hounsfield units [HU]) and 6 months (409.53 ± 46.37 HU; P = 0.381). Significant changes in the distribution of bone height classifications were observed in the labial and palatal sides of the ABG between 3 and 6 months (P = 0.025 for labial bone height, P = 0.008 for palatal bone height). These results indicate that the alveolar density remained stable between 3 and 6 months, whereas bone height level declined during that period after ABG, the latter indicating bone graft absorption over time. It is, therefore, suggested that subsequent orthodontic or dental implants be placed 3 months after ABG rather than at 6 months or later.

Chin bone graft for maxillary alveolar cleft: indications and limitations

BACKGROUND

Alveolar bone grafting (ABG) is an important step in the management of patients with cleft lip and palate. Choice of autogenous bone grafting is critical to achieve the goals of alveolar cleft bone grafting. This study was designed to determine which situations are suitable for obtaining bone from the chin in ABG.

MATERIALS AND METHODS

In a retrospective study, the alveolar clefts that had been bone-grafted from the chin bone were selected from the archived files of the Oral and Maxillofacial Department, Mashhad University of Medical Sciences in 2004 to 2012. The patients were recalled and postoperative panoramic and lateral cephalometry views were obtained.

RESULTS

Seventeen patients were included in this study, with 53% females and 70.5% unilateral maxillary alveolar clefts. The follow-up was from 2 to 6 years. The mean age of the patients at the time of surgery was 17 ± 3.8 years.

CONCLUSION

Harvesting bone from the chin is easy and safe, with low morbidity. Considering the fact that the volume of the harvested bone is low, especially in the presence of unerupted mandibular canine, autogenous chin bone is recommended for late ABG, especially in unilateral cases when the plan is to close the gap in the arch orthodontically while there is no need for lateral piriform augmentation.