Complications Following One-Stage Versus Two-Stage Surgical Treatment of Transverse Maxillary Hypoplasia

Can different osteotomies have an influence on surgically assisted rapid maxillary expansion? A systematic review

The purpose of this study was to systematically review the randomized and non-randomized clinical trials (RCT; nRCT) concerning the different available osteotomies for surgically assisted rapid maxillary expansion (SARME): pterygomaxillary disjunction (SARME + PD vs SARME-PD) and segmental Le Fort I osteotomy (2-piece vs 3-piece). Outcomes focused on skeletal, dental, upper airway changes, complications, and relapse. Two authors investigated five databases (PubMed, Cochrane Library, Google Scholar, Scopus, Web of Science) until August 2023. The Cochrane Collaboration Tool and the Newcastle-Ottawa scale were used for the quality assessment of the included RCTs and nRCTs, respectively. A total of 554 articles were retrieved and after duplicates removing and full-text reading, 40 studies were included. Two RCTs showed a low risk of bias, one an unclear risk and one a high risk. Among the non-RCTs, 15 studies showed a good quality, while 21 exhibited a fair quality score. SARME + PD resulted in more homogeneous posterior bone expansion, with minimal dental effects. No difference between 2-piece and 3-piece in asymmetric expansion was observed, although 3SO showed 1-2 mm of more transverse increase. The oropharynx minimum cross-sectional area, the nasopharynx and the oropharynx volume were greater in SARME + PD. Both dental and bone relapse can occur but no differences between the groups were observed. All osteotomies guaranteed a correction of transverse maxillary deficiency. Lower side effects were described in SARME + PD. Two-piece and 3-piece segmental Le Fort I osteotomies did not show any differences in the symmetry and amount of expansion.

Asymmetric Maxillary Expansion Introduced by Surgically Assisted Rapid Palatal Expansion: A Systematic Review

PURPOSE

A commonly reported complication of surgically assisted rapid palatal expansion (SARPE) that has not been explored extensively is uneven expansion between left and right sides, which requires secondary surgery for correction. This systematic review aims to analyze the prevalence and potential causes of asymmetric expansion in the transverse dimension after SARPE to guide the clinical practice.

METHODS

Electronic databases and manual search were used to search for original articles published on SARPE on March 11, 2022. Original human studies that recorded the number and percentage of asymmetric expansion after two-piece SARPE were included. The 2020 Preferred Reporting Items for Systemic Reviews and Meta-Analyses guideline was implemented for the quality assessment and data analysis of the included articles. The study was registered at the International Prospective Register of Systematic Reviews under the number CRD42022300782.

RESULTS

After applying inclusion and exclusion criteria, 13 articles were included in the final review. The risk of bias was high in 8 studies and medium in the other 5 studies. Overall, the prevalence of asymmetric expansion in the transverse dimension (different amount of expansion between left and right sides) was 7.52%, with 12.90% of patients involved receiving a second surgery for correction. Expander design did not significantly affect the rate of asymmetry expansion. Pterygomaxillary fissure release significantly increased the rate of asymmetry expansion (11.02% vs 5.08%, P < .001). In comparison, lateral nasal wall osteotomy (4.26% vs 14.77%, P < .001) and release of the nasal septum (5.22% vs 17.15%, P < .001) significantly lowered the rate of asymmetry expansion, respectively.

CONCLUSIONS

Asymmetric dentoskeletal expansion between left and right sides is a common complication of SARPE procedures, mostly caused by variations in surgical cuts. However, the risk of bias in currently available publications is high. Further studies are warranted to fully understand the causes of asymmetric expansion.