# Bone-on-Bone Telescopic Fixation With Step-Plate Stabilization: A Novel Approach for Enhanced Stability in LeFort I Maxillary Advancement for Cleft-Related Hypoplasia

## TL;DR

A new surgical technique for correcting maxillary hypoplasia in cleft lip and palate patients shows improved stability and aesthetics with minimal relapse.

## Contribution

Introduces a novel bone-on-bone telescopic fixation with step-plate stabilization technique for LeFort I advancement in cleft-related hypoplasia.

## Key findings

- Only 5% of patients showed clinically significant horizontal relapse after 12 months.
- Facial aesthetic scores improved significantly (from 4.5 to 7.4) with minimal complications.
- Vertical stability was maintained with no significant change over time.

## Abstract

Introduction: Patients with cleft lip and palate (CLP) frequently require secondary LeFort I maxillary advancement due to severe scar-induced relapse with conventional techniques. This study introduced and evaluated bone-on-bone telescopic fixation with step-plate stabilization as a geometry-dependent solution to improve long-term stability. The aim of this study was to assess the skeletal stability, relapse rates, esthetic outcomes, and complications of the novel bone-on-bone telescopic LeFort I advancement technique in cleft maxillary hypoplasia.

Materials and methods: A retrospective analysis of 90 consecutive non-syndromic CLP patients (52 females, 38 males; mean age 21.3 ± 3.8 years) who underwent LeFort I advancement using telescopic bone overlap and custom step-plate fixation between 2021 and 2022 was conducted. The minimum follow-up duration was 12 months. Horizontal and vertical stability was measured cephalometrically preoperatively (T0), immediately postoperatively (T1), and at ≥12-month (T2) intervals. A relapse >2 mm was considered clinically significant.

Results: The mean horizontal advancement was substantial and highly significant (p < .001). At T2, relapse occurred in only 18 patients (20%); 14 patients (15%) showed <2 mm horizontal relapse, and only four patients (5%) showed >2 mm horizontal relapse. The vertical position remained stable (p = 1.0). The maxillary position and maxillomandibular relationship improved significantly and were largely maintained (p < .001). Facial aesthetic scores (FAS) increased from 4.5 ± 1.05 to 7.4 ± 0.94 (p < .001; Cohen's d = 3.68). The incidence of complications was low (nerve disturbance, 7%; infection, 5%; reoperation, 6%). Bone grafting was required in 18 patients (20%). No significant correlation was found between the magnitude of advancement and relapse (r = −0.36, p = 0.121).

Conclusion: The bone-on-bone telescopic technique with step-plate fixation provided superior skeletal stability, minimal clinically relevant relapse, excellent esthetic improvement, and a favorable safety profile, establishing it as a reliable and minimally invasive option for the definitive correction of cleft maxillary hypoplasia.