A Rare Familial Presentation of Facial Talon Cusp

Talon cusp is a rare developmental anomaly presenting as a wisp like structure arising from the cervical region of anterior teeth. They are predominantly seen in permanent dentition with a male predilection and are commonly seen associated with incisors and on the lingual/palatal surface. The aetiology appears to be multifactorial with a possible likelihood of genetic and environmental involvement routing to disturbances in tooth development at the morphodifferentiation stage. Over the years, few cases of talon cusp among the family members have been reported which strongly supports the genetic influence. We report rare presentations of talon cusp among two family members involving the facial surface of incisors.

Non-viral-mediated gene therapy approaches for bone repair

OBJECTIVES

Bone repair strategies continue to be developed for alternatives to autografting, allogeneic implants of banked bone, and other bone substitutes. Efforts have included the delivery of potent growth and/or differentiation factors and the use of gene therapy. For bone regeneration, gene therapy is the delivery, uptake and expression of DNA that has been localized to a wound bed. The objective of the current study is to investigate methods to enhance non-viral-mediated means of gene uptake and expression for use in bone regeneration.

METHODS

Several types of DNA-polymer complexes, either applied directly to baby hamster kidney (BHK) cells, or released from a porous, resorbable gene-activated matrix (GAM), were evaluated in vitro for their ability to transfect cells with a circular plasmid DNA construct expressing green fluorescent protein. Complexes included conjugates containing a lipophilic reagent, liposomes, poly-ethyl-oxazoline, and poly-ethyleneimine (PEI). Data were subjected to analysis of variance and Fisher's protected least significant difference for multiple comparisons with significance established at p < 0.05.

RESULTS

Transfection efficiencies of the liposome and PEI complexes improved in vitro when released from resorbable GAMs. The lipophilic reagent FuGene 6 demonstrated abundant uptake and expression in the initial 1- and 2-day evaluation periods. In contrast, the DNA-liposome and PEI GAM complexes demonstrated a sustained release, uptake and expression by the BHK cells at the 2-, 4-, and 7-day, and 4- and 7-day evaluation intervals, respectively.

CONCLUSION

GAM technology appears to improve the functional stability and release duration of incorporated DNA-polymer complexes in the present in vitro studies. The ongoing objective of our research is to develop a localized treatment to improve the uptake and expression of plasmid DNA by non-viral-mediated gene therapy.