New biomaterials versus traditional techniques: advances in cleft palate reconstruction.

PURPOSE OF REVIEW: Cleft lip and palate still remains one of the most common congenital anomalies, and consequently surgical correction of these anomalies is still commonplace. Despite numerous existing surgical techniques having good outcomes, it is still recognized that the morbidity of certain surgical procedures and success rates regarding outcomes can be improved. The purpose of this review is to evaluate new literature and techniques compared with the time tested procedures that are commonly used. RECENT FINDINGS: As technology continues to advance, the understanding of details regarding biochemical pathways responsible for the development of cleft defects and also the efficacy of biomaterials that can be used in their correction are being discovered and better understood. Many studies have been conducted in both animal and human study participants that further the understanding of these questions. The efficacy and benefit of newly devised biomaterials seems to indicate that these biomaterials are a viable adjunct and often an alternative in the treatment of cleft palate patients. SUMMARY: In this review of recent literature, the discussion begins with a review of the more traditional and widely accepted iliac crest bone grafting and then evolves into a discussion of several animal and human studies to delineate the progress being made in this field. The literature exploring the details regarding biochemical pathways and cellular mediators that are involved in cleft formation, as well as biomaterials used in surgical repair are evaluated. The findings in the literature suggest that there is a bright future in better understanding the cause of cleft formation on a molecular level and associated attempts that can be made in altering some of these factors along with discovering new biomaterials that can be a useful adjunct to existing techniques.

Voltage-gated Ca2+ channel Ca(V)1.3 subunit expressed in the hair cell epithelium of the sacculus of the trout Oncorhynchus mykiss: cloning and comparison across vertebrate classes.

Full-length sequence (>6.5 kb) has been determined for the Ca(V)1.3 pore-forming subunit of the voltage-gated Ca(2+) channel from the saccular hair cells of the rainbow trout (Oncorhynchus mykiss). Primary structure was obtained from overlapping PCR and cloned fragments, amplified by primers based on teleost, avian, and mammalian sources. Trout saccular Ca(V)1.3 was localized to hair cells, as evidenced by its isolation from an epithelial layer in which the hair cell is the only intact cell type. The predicted amino acid sequence of the trout hair cell Ca(V)1.3 is approximately 70% identical to the sequences of avian and mammalian Ca(V)1.3 subunits and shows L-type characteristics. The trout hair cell Ca(V)1.3 expresses a 26-aa insert in the I-II cytoplasmic loop (exon 9a) and a 10-aa insert in the IVS2-IVS3 cytoplasmic loop (exon 30a), neither of which is appreciably represented in trout brain. The exon 9a insert also occurs in hair cell organs of chick and rat, and appears as an exon in human genomic Ca(V)1.3 sequence (but not in the Ca(V)1.3 coding sequence expressed in human brain or pancreas). The exon 30a insert, although expressed in hair cells of chick as well as trout, does not appear in comparable rat or human tissues. Further, the IIIS2 region shows a splice choice (exon 22a) that is associated with the hair cell organs of trout, chick, and rat, but is not found in human genomic sequence. The elucidation of the primary structure of the voltage-gated Ca(2+) channel Ca(V)1.3 subunit from hair cells of the teleost, representing the lowest of the vertebrate classes, suggests a generality of sensory mechanism for Ca(V)1.3 across hair cell systems. In particular, the exon 9a insert of this channel appears to be the molecular feature most consistently associated with hair cells from fish to mammal, consonant with the hypothesis that the latter region may be a signature for the hair cell.

Update on craniofacial surgery.

Over the course of the past year, many interesting aspects of the multidisciplinary approach to the treatment of craniofacial disorders have been furthered. Several authors have shared their experiences, and new innovations have been described. Traditional ideas with regard to bone healing and growth have been expanded upon, and the role of alloplasts also is better understood now. Diagnosis and treatment planning have come a long way with the advent of new imaging techniques and applications. The ongoing discussion regarding absorbable fixation devices has continued, and the development of new technology has been presented. Some new techniques have also been brought to the forefront. Of note, distraction osteogenesis has been embraced as a viable alternative to traditional maxillomandibular surgery with bone grafting as well as other morbid procedures.