Evaluation of Treatment Outcome in Cleft Maxillary Hypoplasia Treated by Rigid External Distractor: A Cephalometric Study

Effects of anterior maxillary distraction compared to LeFort-1 osteotomy and total maxillary distraction osteogenesis for treating hypoplastic maxilla in patients with cleft lip and palate- A systematic review and meta-analysis

OBJECTIVE

To compare the treatment outcomes and effectiveness of Anterior Maxillary Distraction (AMD) with the LeFort I Osteotomy and Total Maxillary Distraction Osteogenesis (TMDO) to treat cleft maxillary hypoplasia.

METHODS

(PROSPERO CRD42020223345) Thorough electronic search of seven databases, unpublished gray literature, and a hand search of the relevant studies reference lists was done. Studies assessing mid-facial skeletal, dentoalveolar, and soft-tissue outcomes of AMD in patients >8 years of age, hypoplastic cleft maxilla, and with either TMDO/LeFort 1/ both as control groups were included. Seven included articles were assessed for the study characteristics and qualitative synthesis. Three studies were analyzed quantitatively using the RevMan 5.4 software. The quality of studies was assessed using Cochrane ROB2 and the overall certainty of evidence using GRADE.

RESULTS

AMD was performed in 241 subjects, LeFort 1 in 145 subjects, and TMDO in 42 subjects. Maxillary advancement for AMD and LeFort 1 groups showed no statistically significant difference (Mean Difference, MD -0.64°) while TMDO showed statistically significant advancement than AMD (MD -1.44°). Statistically significant upward rotation of anterior maxilla was noted with AMD (MD -6.15 degrees) than Lefort 1. Upper incisor inclination improved in both AMD and TMDO groups (MD 1.5°). Improvement in the maxilla-mandibular relationship, convexity of face, lip and nose, and marked dentoalveolar changes in overjet and upper incisor position were noted in all the three groups. Discernible airway alterations were noted in LeFort 1 and TMDOs. Total relapse was the least with AMD.

CONCLUSION

Distraction osteogenesis exhibited better dento-skeletal outcomes and minor skeletal relapse than LeFort 1. TMDO is a preferred modality in treating severe maxillary hypoplasia associated with CLP than AMD. Further long-term prospective comparative studies are required, possibly involving the patient-centric merits.

Comparison of long-term skeletal stability following maxillary advancement using rigid external distraction in growing and non-growing patients with cleft lip and palate: a systematic review and meta-analysis

OBJECTIVES

To compare the long-term skeletal stability following maxillary advancement using Rigid External Distraction (RED) in growing and non-growing patients with Cleft Lip and Palate (CLP).

METHODS

Data sources: A systematic literature search was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines from database inception till August 2020 in MEDLINE-PubMed, Cochrane Central Register of Controlled Trials (CENTRAL), Science Direct, Google Scholar and a manual search in the institutional library. Study eligibility criteria, participants and intervention: All available literature published in English, with a minimum of six human subjects with well-defined age range either 7-14.9 years or 15-30 years, follow up period of a minimum of 12 months assessing the skeletal stability as horizontal change at Point A (Subspinale) following maxillary advancement using a RED device, without the use of rigid internal fixation or bone grafts were included in the study. Study appraisal and synthesis method: The quality assessment of selected articles was done using the Newcastle-Ottawa scale. The meta-analysis was carried out with Q statistic method, I-squared statistics, fixed-effect model to estimate pooled mean and Begg-Mazumdar bias indicator.

RESULTS

Selected nine articles that were qualitatively assessed for relapse rate following maxillary advancement using a RED device, showed consistent and stable results. The meta-analysis found no significant difference in long-term skeletal stability of maxillary advancement by RED device in growing and non-growing patients with CLP [(growing group: Pooled proportion = 0.2927; 95% CI = 0.1534 to 0.4319) (non-growing group: Pooled proportion = 0.23077; 95% CI = 0.09854 to 0.36300)].

LIMITATIONS

No study, as revealed by the search, was available that compared the two groups as defined by the inclusion criteria. Data for the two groups were retrieved from different studies and meta-analysed.

CONCLUSION

RED is an effective modality for correction of maxillary hypoplasia secondary to CLP, requiring large maxillary advancement. The technique can be used in young and adult patients with similar long-term results.

PROSPERO REGISTRATION NUMBER

CRD42020205513.

Distraction Osteogenesis Plus Permanent Rigid Fixation for Mandibular Deformities in Nongrowing Patients: A Comparative Study

ABSTRACT

Distraction osteogenesis (DO) is a commonly used intervention of mandibular deformities. However, relapse of the newly constructed mandible is a significant concern. The present comparative study aimed to investigate use of rigid fixation in addition to DO in management of mandibular deformities. The present study included 20 patients with mandibular deformities indicated for DO. The study comprised 10 patients who agreed to perform rigid fixation (DO + RF) and other 10 patients who refused to perform the additional procedure (DO). All patients were subjected to standard mandibular DO. In patients subjected to additional RF with plate and screws, on the last day of distraction, the distractor is removed in the theatre under general anesthesia. Then by an intraoral incision on the previous scar, the distracted part is explored and the plate is applied in the lower part of the mandible to avoid destruction of the teeth roots. All patients are subjected to close observation and radiological evaluation for the appearance of any complication, signs of relapse at the intervals of 1 week and 6 months and 1 year. At the end of follow-up, 2 patients in the DO + RF group relapsed while all patients in the DO only group relapsed (P < 0.001). The relapsed distance was significantly greater in the DO group [(median (range): 0.3 (0.1-1.3) versus 0.0 (0.0-0.2), P ≤ 0.001]. DO + RF provided significantly lower rate and distance of relapse in nongrowing patients with mandibular deformities.

Efficacy of Maxillary Anterior Segmental Distraction Osteogenesis in Patients With Cleft Lip and Palate

OBJECTIVES

To evaluate the effects of maxillary anterior segmental distraction osteogenesis (MASDO) in patients with cleft lip and palate (CLP) and to identify risk factors for increased relapse.

DESIGN

A retrospective study.

PATIENTS

Thirty-one Japanese patients with CLP who underwent MASDO were eligible for study inclusion.

MAIN OUTCOME MEASURES

We evaluated lateral cephalograms obtained before (T1), at 3 months (T2), and at 1 year (T3) after MASDO, and measured changes from T1 to T2 (δT1T2), from T2 to T3 (δT2T3), and from T1 to T3 (δT1T3). We also evaluated the risk factors associated with an increased relapse.

RESULTS

Overall (δT1T3), MASDO improved retrusion of the maxilla. We measured a significant advancement (6.1 mm) of the anterior maxillary segment in δT1T2 (A-McNamara classification) and increases in the overjet and the SNA, ANB, and nasolabial angles. However, skeletal relapse was evident in δT2T3, and the median percentage of relapse was 10%. To explore the risk factors, we subdivided patients with a δT1T2 of >5 mm into 2 groups based on the percentage of relapse (>15% vs ≤15%). There were significant differences between these groups in the vertical positions of the anterior nasal spine and point A, and the angle formed by the SN and palatal planes (SNPP), suggestive of intraoperative counterclockwise rotation of the maxilla.

CONCLUSIONS

MASDO is effective for correcting midfacial deficiencies, but counterclockwise rotation of the maxilla during surgery may cause relapse.