Three-dimensional assessment of maxillary arches in patients with unilateral cleft lip and palate treated with different orthopedic presurgical procedures: case series

BACKGROUND: The management of unilateral complete cleft lip and palate patients (UCCLP) requires a combination of orthopedics and surgery. Depending to the forces involved, pre-surgical orthopedic appliances are classified into active or passive. An active approach employs controlled forces to move maxillary segments in the direction of where alveolar bone apposition is desired, while passive devices act as an obturator that covers the palate and maintains the distance between the two maxillary segments. Nowadays, increasing number of cleft centres uses 3D model imaging and landmark digitization in order both to obtain repeated measurements of all casts (minimizing interoperator and intraoperator error) and improve accuracy of data analysis, sharing and storage for documentation and research purposes. Aim of the cast study is a three dimensional analysis of subsequent changes to maxillary arches following different orthopedic procedures in the treatment of patients with UCCLP. METHODS:Two male patients with congenital non-syndromic unilateral complete cleft lip and palate (III Veau class) on the left side are considered to enter the study. The inclusion criteria are the absence of syndromic or medically compromised conditions. The exclusion criteria is the presence of prior surgical or orthopedic treatments. The study reports the results achieved at the last month of the therapy. A putty-wash procedure was adopted: patients underwent an initial impression taken by a silicone putty-dough of heavy consistency with a light-cured acrylic custom-made impression tray and then a light-consistency polyvinyl elastomeric fast-setting material was placed exclusively in the tray above the heavy stage for the final impression. After an ADA Type III plaster cast was poured, an hard self-cured acrylic resin plate was realized. All the orthopedic devices were fabricated by the same laboratory technician. In patient A, the stone cast was duplicated and then discarded 1 mm in the midsagittal plane before plate realization in order to reduce the transversal discrepancy between maxillary segments prior to surgery. The cast replica was used to realize a custom tray. In patient B, after alveolar segments had achieved a proper alignment, clinicians decided to realize a final passive plate in order to avoid recurrence. The current study considers stone casts obtained 1 month before the try-in and delivery of the orthopedic appliance and 1 month later. The models were digitized using a 3-axis scanner (Zenotec S50, Wieland) that captures all data by means of laser triangulation. All measurements were carried out blindly to the patient group. The authors identified landmarks on all palates and superimposed the pre-treatment and post-treatment models using a three-dimensional (3D) software (Geomagic Control, 3D Systems Inc, Cary, NC), thus assessing the qualitative and quantitative changes of presurgical infant orthopedics.