Abstract: NAM Vs Lip Adhesion: A Cephalometric Comparison

Abstract

BACKGROUND: Patients with cleft lip and palate frequently undergo nasoalveolar molding (NAM) or lip adhesion (LA) to guide the cleft segments together in preparation for definitive repair. This study reports the effect of these primary interventions on eventual permanent incisor inclination. METHODS: This is a retrospective study at a tertiary craniofacial center. Patients with unilateral or bilateral cleft lip and palate, who had undergone LA or NAM, with follow-up imaging between ages of 7–9 were included. Patients were further categorized based on gingivoperiostioplasty (GPP) status. Patients with phase one orthodontic therapy were excluded. Cephalogram analysis used Dolphin software (©Dolphin imaging and management solutions). Measures taken: U1-NA(mm) and U1-SN, U1-FN, U1-NA, SNA, SNB, ANB (°) and were compared to Bolton normative measurements. RESULTS: Inclusion criteria yielded 50 children who received NAM (22 patients with GPP) and 18 children who received lip adhesion (2 patients with GPP). U1-SN angle was 73.6° for NAM and 88.4° for lip adhesion (p<0.0033). U1-FH angle was 83° for NAM and 96.3° for lip adhesion (p<0.0057). U1-Na angle was -2.1° for NAM and 10° lip adhesion (p<0.025). U1-Na distance was not significantly different between treatment groups. Differences in angles ANB, SNB and SNA were non-significant. Overjet (mm) was -7.07 and-1.65 for NAM and LA, respectively (p<0.028). Proportion of patients with overjet was 10 and 35.3%, respectively and for underjet 78 and 47.1%, respectively (P<0.002). Combining NAM and lip adhesion patients: U1-SN angle, U1-FH angle, U1-NA angle were 82.3, 91.1 and 7.6° respectively for unilateral cleft patients and 69.4, 78.8 and -9.4° respectively for bilateral cleft patients (p<0.05). ANB was 0.79 and 3.53 degrees for unilateral and bilateral clefts, respectively (p<0.0156). No other significant differences were identified. None of the parameters above showed any significant correlation with patient age at time of scan nor the use of GPP (p>0.05). CONCLUSION: LA and NAM cause deviation from normal in U1-SN, U1-FH, U1-NA and overjet with NAM having a greater effect. Bilateral clefts treated with NAM or LA deviated more in these parameters than unilateral clefts. Age at cephalometry and history of GPP had no significant affect. This may have significant implications for the phase I orthodontic options, time in treatment and potential dental morbidity due to traumatic occlusion and functional occlusal shifting.