A multicenter retrospective 3D study of serial complete unilateral cleft lip and palate and complete bilateral cleft lip and palate casts to evaluate treatment: part 1--the participating institutions and research aims.

OBJECTIVE: To compare the multicenter retrospective and prospective spatiotemporal (4D) serial analyses of complete unilateral (CUCLP) and complete bilateral (CBCLP) cleft lip and palate casts that had undergone different treatment procedures. The involved institutions are Miami Craniofacial Anomalies Foundation, South Florida Cleft Palate Clinic; University Hospital of Nijmegen Cleft Palate Center; Free University of Amsterdam Cleft Palate Center; Academic Hospital (Dijkzigt/Sophia) Rotterdam Cleft Palate Center; Center for Craniofacial Anomalies, University of Illinois College of Medicine; Cleft Palate Center, Sahlgrenska University Hospital, Göteborg, Sweden; and Children's Memorial Medical Center, Northwestern University Cleft Palate Institute.
DESIGN: Using serial casts of the upper jaw and an electromechanical digitizer with special Cad-Cam software (CadKey), the occlusal relationships and morphometric palatal growth changes that occur under the influence of presurgical orthopedics and various surgical procedures will be studied. It is anticipated that 3D geometric data extracted from serial casts will identify the important geometric palatal parameters present before cleft surgical closure, which will supply objective criteria for establishing a scientific basis for improved surgical therapy. This research study will test three hypotheses: (1) Conservative (varying the timing of surgical cleft closure according to the size of the cleft space) lip and palatal surgery will permit "catch-up" palatal growth and normalize palatal growth and development. (2) The amount of mucoperiosteal tissue relative to the size of the cleft space is important in determining the timing of palatal surgery, as it influences the degree of scarring and ultimately the palate's adult size and form. (3) Presurgical orthopedics (the use of appliances soon after birth) can stimulate palatal growth beyond its normal growth potential.
RESULTS: In a previous project and again after reviewing the data already collected during the first year of this study, it has been shown that incremental changes in size of palatal segments in CUCLP and CBCLP cases prior to surgery vary slightly. The CBCLP cases grow slightly faster than CUCLP cases before surgery, but growth of the CBCLP cases decreases in acceleration after surgery. Reasons for these differences will be determined when more cases are analyzed and subjected to biostatistical analysis.