The Development of Nonanatomic Denture Occlusion: Part III.

Part III of this four-part series about nonanatomic denture tooth development traces the evolution of this movement from the mid-1930s through the World War II era up to the early 1950s. By this time, the general preference for posterior denture occlusion had shifted from anatomic to nonanatomic teeth, and all the major denture tooth manufacturing companies listed at least one nonanatomic design in their inventories.

The Development of Nonanatomic Denture Occlusion: Part IV.

This fourth and final part of a four-part series concerned with the development of nonanatomic denture occlusion follows nonanatomic tooth design from the time of Victor Sears' first nonanatomic tooth patent through the end of the 20th century. Part IV concentrates on nonanatomic teeth developed during the last five decades of the 20th century. Many of the designs featured in this series exhibited genius, while others are pure nonsense. Sears claimed that a new nonanatomic tooth design appeared every 9 months on average during the first 30 years of nonanatomic tooth production. Many current nonanatomic tooth patents are further refinements of those earlier designs.

The Development of Nonanatomic Denture Occlusion: Part II.

This second part of a four-part series concerned with the development of nonanatomic denture occlusion follows nonanatomic tooth design from the time of Victor Sears' first nonanatomic tooth patent through the mid-1930s. Many of the designs featured in this series exhibit genius, while others are pure nonsense. Sears claimed that a new nonanatomic tooth design appeared every 9 months on average during the first 30 years of nonanatomic tooth production. Many current nonanatomic tooth patents are further refinements of those earlier designs. Part II reviews pioneering designs that appeared during the first dozen or so years of this paradigm shift in denture occlusion philosophy.

Structure and in vitro cytocompatibility of the gastropod shell of Helix pomatia.

Distinguishing features of biological constructions are high stability and adaptation to their environment. Beside biocompatibility, nontoxicity and degradability these characteristics are demanded for new biomaterials in the field of tissue engineering. This study investigated the chemical composition, the organization and the in vitro osteoconductive potential of the terrestrial gastropod shell (Helix pomatia) on CAL72 and human osteoblast-like cells. Chemical composition of the biomaterial was examined by X-ray diffraction (XRD) and scanning electron microscopy (SEM) was performed to analyze the architecture of the snail shell and the morphology of the seeded cells. A double staining procedure (FDA/PI) and a proliferation test (EZ4U) assessed the viability of the cells. Microscopical images showed the multilayered architecture of the aragonite shell with hexagonal crystals on the inner side. The cells spread well on the biomaterial and the highest proliferation rate could be measured with CAL72 cells on the inner shell surface. The osteoconductive effects of this natural biomaterial could encourage further experiments in the field of tissue engineering.

Estudo da inclinaçäo das vertentes das cúspides de suporte, em relaçäo ao plano áxio-orbital, em dentes naturais e duas marcas de dentes artificiais utilizados em prótese parcial removível / A study of the inclination of supporting cusp slopes, in relation to the axio-orbital plan, on natural teeth and two brands of artificial teeth utilized in removable partial prosthodontics

Pela técnica da estereometria, foram analisadas, em relaçäo ao plano áxio-orbital, as inclinaçöes das vertentes triturantes distais superiores e mesiais inferiores das cúspides de suporte. Essas vertentes säo as superfícies onde podem ocorrer interferências em balanceio, consideradas entre as mais danosas ao sistema estomatognático. O estudo foi realizado em 5 pacientes com dentes íntegros e oclusäo ideal sem disfunçäo do sistema estomatognático. Foram analisadas 3 situaçöes de dentiçäo para cada paciente, ou seja, a primeira na condiçäo de dentes naturais, a segunda com dentes artificiais Trubyte Biotone 33º, e a terceira, com dentes artificiais Orthosit PE. Dentro das condiçöes experimentais desta pesquisa, chegamos à conclusäo de que, em dentes naturais, as vertentes analisadas apresentam uma semelhança estatística entre si, ou seja, parece existir um paralelismo relativo entre elas. Observou-se, também que näo há correspondência entre as inclinaçöes das vertentes analisadas dos dentes superiores com as suas respectivas vertentes antagônicas inferiores. A inclinaçäo cuspídica dos dentes inferiores foi sempre maior em relaçäo aos superiores, e esse fato ocorreu com maior amplitude nos dentes artificiais. Os dois tipos de dentes artificiais testados näo apresentaram as inclinaçöes das vertentes analisadas, perfeitamente compatíveis com as dos dentes naturais. Entretanto, os dentes Trubyte Biotone com 33º de inclinaçäo cuspídica foram os que mais se aproximaram das inclinaçöes médias dos dentes naturais. Estes, sob aspecto da anatomia oclusal, parecem ser os mais indicados para se utilizar em próteses parciais removíveis