Systematic Review and Critical Appraisal of the Evidence Base for Nasoalveolar Molding (NAM)

To critically appraise the body of scientific literature supporting the risks and efficacy of nasoalveolar molding (NAM), specifically in contrast to alternative methods of presurgical infant orthopedics (PSIO) or to treatment without PSIO.

Five outcome domains were considered: nasolabial aesthetics; dentoalveolar relationship; midfacial growth; cost and burden of care; and number of anesthetic events.

MEDLINE, Embase, and Scopus were queried for articles from the first description of the Grayson-Santiago NAM technique (1993) through December 13, 2021. After the application of inclusionary and exclusionary criteria, selected articles were critically appraised using a systematic framework that included risk of bias assessment using the Cochrane RoB 2.0 and ROBINS-I tools.

A total of 88 studies were included. Level-I and -II evidence showed on par or better approximation and alveolar alignment achieved by NAM compared to other PSIO. Level-II and -III evidence showed improved nasolabial aesthetics compared to other PSIOs. Level-II and -III evidence supported no harm to maxillofacial skeletal growth through age 12. Sparse level-III evidence supported a reduced number of labial or nasal revisions following NAM. Level-II and -III evidence showed NAM requiring upfront cost and frequent appointments but reducing caregiver psychosocial burden and reducing long-term costs compared to select alternatives. Many studies carried a high risk of bias.

Current evidence supports the overall efficacy of NAM regarding short/mid-term outcomes, with a low risk of negative effects on midfacial growth or dental development. The high risk of bias discovered in many papers underscores the need for robust study design in future research.