Cleft Lip And Other Malformations

Recent litigation has brought to light the possible link between some medications and birth defects such as cleft lip and cleft palate. One interesting article is called, Association Between Cleft Lip With Or Without Cleft Palate And Prenatal Exposure To Diazepam The Lancet, Volume 306, Issue 7933, Pages 478-480 by M.Safra. Here is an excerpt: Abstract - From 278 interviews of women who had infants with selected major malformations, a history of diazepam ingestion in the first trimester of pregnancy was found to be four times more frequent among mothers of children with a cleft lip with or without a cleft palate than among mothers of children with other defects. This association was one of many that was examined in the analysis; thus it is quite possible that it is simply due to chance. This report, however, is the second one linking diazepam to cleft lip with or without cleft palate. Until there are more data bearing on this question, this possible risk should be considered when prescribing diazepam for women in their reproductive years.

Another interesting study is called, Strong Evidence of Linkage Disequilibrium between Polymorphisms at the IRF6 Locus and Nonsyndromic Cleft Lip With or Without Cleft Palate, in an Italian Population by Luca Scapoli, Annalisa Palmieri, Marcella Martinelli, Furio Pezzetti, Paolo Carinci, Mauro Tognon, and Francesco Carinci - The American Society of Human Genetics. Volume 76, Issue 1, 180-183, 1 January 2005. Here is an excerpt: Abstract - Cleft lip with or without cleft palate (CL/P) is one of the most common birth defects, but its etiology is largely unknown. It is very likely that both genetic and environmental factors contribute to this malformation. Mutations in the gene for interferon regulatory factor 6 (IRF6) have been shown to be the cause of Van der Woude syndrome, a dominant disorder that has CL/P as a common feature. Recently, it has been reported that genetic polymorphisms at the IRF6 locus are associated with nonsyndromic CL/P, with stronger association in Asian and South American populations. We investigated four markers spanning the IRF6 locus, using the transmission/disequilibrium test. A sample of 219 Italian triads of patients and their parents were enrolled in the study. Strong evidence of linkage disequilibrium was found between markers and disease in both single-allele (P=.002 at marker rs2235375) and haplotype (P=.0005) analyses. These findings confirm the contribution of IRF6 in the etiology of nonsyndromic CL/P and strongly support its involvement in populations of European ancestry.

Another interesting study is called, Secondary Bone Grafting of Alveolar Clefts: A Surgical/Orthodontic Treatment Enabling a Non-prosthodontic Rehabilitation in Cleft Lip and Palate Patients 1981, Vol. 15, No. 2 , Pages 127-140 by Frank E. byholm1, Olav Bergland1 and Gunvor Semb - Department of Plastic Surgery, Rikshospitalet; the Department of Odontology, National Center for Logopedics; and the Department of Orthodontics, Dental Faculty, University of Oslo, Oslo, Norway. Here is an excerpt: A procedure combining grafting of cancellous bone to the residual cleft of the primary palate with subsequent orthodontic movement of teeth into the former cleft area is described. The preliminary results from the first 80 patients (89 clefts) are presented. The age of the patients at the bone grafting ranged from 8 to 18 years, and the observation time from 17 to 44 months. The results have been assessed 1) on the basis of dental radiographs and 2) clinically, by the response of the grafted area to the orthodontic movement of adjacent teeth. In 69 clefts in which the cleft side canine had been brought into its final position at the time of evaluation, the height of the interal-veolar septum was assessed to be approximately normal in 38% and slightly less than normal in 44%. A septum of insufficient height (less than 3/4 of the normal) had formed in 5 clefts (7%). Even in these cases, the main objects of the operation were fulfilled: The maxillary segments were stabilized, the teeth adjacent to the cleft had better bone support, and the gap in the dental arch could be closed orthodontically in four of the five clefts. Failures, i.e. no continuous bone bridge across the alveolar cleft, were recorded in 8 instances (9%) of the total material.

We all owe a debt of gratitude to these researchers for their fine work and dedication. For more information, please read the studies in their entirety.