Facilitating CAD/CAM nasoalveolar molding therapy with a novel click-in system for nasal stents ensuring a quick and user-friendly chairside nasal stent exchange

Florian D Grill,Markus Eblenkamp,Klaus-Dietrich Wolff,Franz X Bauer,Maximilian Roth,Andrea Rau,Denys J Loeffelbein,Lucas M Ritschl,Hannes Dikel

doi:10.1038/s41598-018-29960-z

Abstract

Nasoalveolar molding (NAM) aims to improve nasal symmetry with a nasal stent in cleft lip and palate (CLP) patients. When plates have to be exchanged because of dentoalveolar growth or cleft reduction, the nasal stent has to be mounted onto a new plate. This procedure elongates visiting hours for patients and parents or requires second treatment sessions. This study introduces a quick-lock additive manufacturing solution for chairside nasal stent exchange called RapidNAM. A novel taping retention pin has been designed that enables nasal stent insertion. Patients with unilateral CLP were included in this study. Plaster models were digitalized and measured by two independent observers. Two methods of CAD/CAM-molding therapies were compared: (i) conventional adhesion of a nasal stent (CAD/CAM NAM); (ii) quick-lock system in which the nasal stent was transferred to another plate (RapidNAM). CAD/CAM NAM and its refinement RapidNAM significantly increased the cleft-side nasal height and tilted the nose towards symmetry. The quick-lock system minimizes wire adaptations, since the pre-existing stent can be reused. The new nasal stent development seems a feasible solution to minimize visiting hours but with clinically satisfactory results. This new nasal stent system combines traditional elements of NAM with CAD/CAM-technology.

Highlights

Nasoalveolar molding (NAM) is a presurgical treatment modality of cleft lip and palates (CLP)
Two groups were formed: one group had been previously treated with conventionally CAD/CAM-intraoral molding plates that were designed digitally[13,14], whereas the other group had been treated with RapidNAM, which included the novel nasal stent system
The following points on the nose were selected by two independent observers (Fig. 2): alar bases (AB, AB’), nasal tip (NT), subnasal point (SN), most anterior point of the columella (CA), top (NT, NT’) and bottom (NB, NB’) of the nostril on the healthy and the cleft side, inner rim to the left and right of each nostril (NL, NL’ and NR, NR’), and points that had the shortest connection line passing over the cleft on the vermilion of the lip (L, L’)

Summary

Introduction

Nasoalveolar molding (NAM) is a presurgical treatment modality of cleft lip and palates (CLP). The alar base is situated laterally, resulting in a sigmoid shape of the nostril This displacement is the target of the nasal molding part of NAM, taking advantage of the ability to mold cartilage within the first few weeks of life[2,3]. Dimensions of the maxilla, the nasal stent has to be newly integrated after checking the fit and the attachment of the plate on the alveolar arches This involves either a second treatment appointment, or the treatment session has to be disrupted by stent integration by the dental technician. Our intention was to modify our pre-existing CAD/CAM solution for a virtual production of intraoral molding plates This design allows a quick chairside change of nasal stents reducing the duration of the treatment session, saving valuable time for the patients and their parents and for the practitioners. The presented system combines traditional and well-established features of NAM with the advantages of additive manufacturing

Methods

Results

Conclusion