# Risk factors associated with the failure of secondary alveolar bone grafting with autologous iliac crest bone in patients with alveolar cleft defects: a systematic review

## TL;DR

This study reviews risk factors for failed bone grafting in patients with alveolar cleft defects, identifying age, oral hygiene, and tooth eruption as key factors.

## Contribution

Systematically identifies and summarizes risk factors for secondary alveolar bone grafting failure using autologous iliac crest bone.

## Key findings

- Increased age at surgery is a significant risk factor for graft failure.
- Poor oral hygiene and erupted lateral or canine teeth are associated with higher failure rates.
- Non-Caucasian ethnicity and large cleft size also increase the risk of graft failure.

## Abstract

This study aimed to perform a systematic review of the risk factors associated with secondary alveolar bone grafting (SABG) failure in patients with cleft alveolus.

A comprehensive search was conducted across PubMed, Scopus, Embase, and Web of Science databases from their inception to 24 February 2025, to identify relevant studies. The search keywords included “alveolar cleft” combined with either “survival” or “failure.” Studies that investigated risk factors for the failure of SABG using autologous iliac crest bone were included in this review. Relevant data, including odds ratios, hazard ratios, or comparisons of variables between patients with and without SABG failure, were recorded and analyzed.

A total of nine studies, encompassing 1,855 grafts, were included. The most commonly used definition of SABG failure was Bergland grade 3 or 4. Reported failure rates varied significantly across studies, ranging from 1.0% to 45.1%. The primary risk factors for SABG failure included increased age at SABG (reported in four studies), poor oral hygiene (two studies), and the presence of an erupted lateral or canine tooth (three studies). Additionally, non-Caucasian ethnicity, international adoptee, large cleft size, a history of cleft lip/palate revision or oronasal fistula, nasoalveolar molding, and premaxillary osteotomy were also associated with a higher risk of SABG failure. No significant association was found between SABG failure and sex, alveolar cleft type (bilateral or unilateral), preoperative expansion, or preoperative orthodontics.

The definition of SABG failure varied across studies, with Bergland grade 3 or 4 being the most commonly used criteria. The primary risk factors for SABG failure included increased age, poor oral hygiene, and the presence of an erupted lateral or canine tooth. Surgeons should be aware of these risk factors to optimize surgical strategies and guide patients effectively.