Dental tissue regeneration - a mini-review.

BACKGROUND: with today's 21st century technological advancements, it is expected that individuals will either retain their natural teeth or obtain functional tooth replacements throughout their entire life. Modern dental therapies for the replacement of missing teeth largely utilize partial or complete dentures and titanium implants capped with prosthetic crowns. Although these prostheses serve a purpose, they are not equivalent, neither in function nor aesthetics, to natural teeth. Recent progress in dental tissue engineering has lent significant credibility to the concept that biological replacement teeth therapies may soon be available to replace missing teeth. OBJECTIVE: in this review, we summarize the emerging concepts of whole-tooth replacement strategies, using postnatal dental stem cells (DSCs) and dental tissue engineering approaches. METHODS: we provide a thorough and extensive review of the literature. RESULTS: current approaches to achieve clinically relevant biological replacement tooth therapies rely on the cultivation of DSCs capable of relaying odontogenic induction signals, through dental epithelial-mesenchymal cell interactions. DSC expansion and differentiation can be achieved by programming progenitor stem cells to adopt dental lineages, using instructive, bioengineered scaffold materials. Periodontal ligament regeneration in particular has demonstrated significant progress recently, despite the somewhat unpredictable clinical outcomes, with regard to its capacity to augment conventional metallic dental implants and as an important component for whole-tooth tissue engineering. Following recent advances made in DSC and tissue engineering research, various research groups are in the midst of performing 'proof of principle' experiments for whole-tooth regeneration, with associated functional periodontal tissues. This mini-review focuses on recent and promising developments in the fields of pulp and periodontal tissue DSCs that are of particular relevance for dental tissue and whole-tooth regeneration. CONCLUSION: continued advances in the derivation of useable DSC populations and optimally designed scaffold materials unequivocally support the feasibility of dental tissue and whole-tooth tissue engineering.

Simultaneous genotyping of single nucleotide polymorphisms in the IL-6, IL-10, TNFalpha and TNFbeta genes.

Single nucleotide polymorphisms (SNP) in the human IL-6, IL-10, TNFalpha and TNFbeta genes have been associated with gene function and susceptibility to disease. In this study, primers containing mismatches at 1-3 nucleotide positions were designed to incorporate a new restriction site recognized by endonucleases AlwNI, BcgI, BglI, BsaBI, BslI, BstXI, EcoNI or XcmI for genotyping SNPs in the IL-6 gene (position - 174), IL-10 gene (positions -592 and -1082), TNFalpha gene (positions -238, - 308 and -863) and TNFbeta gene (position + 249) by mismatched polymerase chain reaction and restriction fragment length polymorphism (PCR/RFLP). Our results show that appropriately designed BslI-based mismatched PCR/RFLP assays can be successfully used to determine the genotypes for approximately 40% of SNPs. The mismatched PCR strategy can be coupled with multiplex-amplification to enable simple and rapid determination of several SNP genotypes in a single reaction.

Langerhans cell histiocytosis in a child while in remission for acute lymphocytic leukemia.

The occurrence of Langerhans cell histiocytosis (LCH) and malignancy in the same patient is rare. When LCH occurs concomitantly with acute leukemia, distinct temporal patterns often exist; acute myelogenous leukemia (AML) typically succeeds LCH, whereas acute lymphocytic leukemia (ALL) usually precedes it. We report a case of LCH developing in a child while in remission for ALL. Unique features of this case include the disseminated nature of the LCH and the death of the patient from LCH rather than ALL.

Early detection of skin cancer: racial/ethnic differences in behaviors and attitudes.

Data from 384 individuals participating in a worksite skin cancer screening program were used to assess racial/ethnic differences in attitudes toward and practice of prevention and early detection of skin cancer. Caucasians and Hispanics were more likely than African Americans to report having used a sunscreen during the past year. Caucasians performed skin self-examination more frequently than Hispanics, but African Americans did not differ in their frequency of skin self-examination from the other two groups. African Americans and Hispanics reported that they would be less likely than Caucasians to seek immediate follow-up care for suspicious skin lesions. Both similarities and differences were found in a variety of health belief variables across the three groups. These findings suggest a need for intensified efforts at primary and secondary prevention of skin cancer among African Americans.