Field emission in-lens SEM study of enamel and dentin

Abstract

This investigation used field emission in-lens scanning electron microscopy (FEISEM) for the study of tooth surfaces, with particular reference to adhesive bonding and acid conditioning. Dentin wafers with an intact enamel periphery were treated by either ethylenediaminetetraacetic acid (EDTA) (pH 7.4) or phosphoric acid (pH 0.7). The samples were then fixed, sequentially dehydrated in alcohol, and either air- or critical point-dried. After coating, surfaces were examined by FEISEM. For enamel, intraprismatic crystals were clearly recognizable, with the crystals showing both a longitudinal and parallel orientation to the long axis of the prisms. For dentin, the surface ultrastructure (mineral crystals and collagen banding) for the both untreated and treated samples was observed. Fine structures measuring on the order of 6 nm were also observed on samples treated by EDTA. We conclude that FEISEM can routinely provide high-resolution images of enamel and dentin, and that it has the capability of revealing the defined distribution of crystals and collagen fibers in dental tissues.

Effect of EDTA conditioning on cervical restorations bonded with a self-etch adhesive: A randomized double-blind clinical trial

“…36,37 Unfortunately, the pre-treatment with EDTA did not improve the marginal adaptation and discoloration. The 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 j o u r n a l o f d e n t i s t r y x x x ( 2 0 1 5 ) x x x -x x x enamel conditioning pattern produced with EDTA created a relatively smooth appearance 38 that was similar to the intact enamel surface, 39 even with increased EDTA concentrations or application times. 39 However, this marginal deterioration may not be considered a clinical failure.…”

Influence of bioactive materials used on the dentin surface whitened with carbamide peroxide 16%

“…Respected authors 19,20 use microscope images in high resolution to study the demineralization and remineralization phenomenon, both in dentin and enamel. The observation of structural and ultra-structural changes can enhance the understanding of the modifications caused by the use of whitening gels, therefore the use of high resolution and higher magnification images is recommended.…”

Influência de materiais bioativos sobre a dureza, ultraestrutura e conteúdo mineral de dentes clareados: estudo in situ

“…Em virtude dessa altíssima capacidade de resolução, o FEG torna-se um equipamento bastante indicado para a avaliação morfológica da estrutura dental clareada, pois permite a observação de alterações sutis e, com isso, torna-se possível detectar processos iniciais de dissolução dos tecidos [22] . Contudo o FEG ainda é um equipamento pouco utilizado na Odontologia.…”

“…A alta resolução das imagens obtidas, usando-se o FEG-SEM, permite que alterações sutis sejam observadas e com isso, processos iniciais de dissolução tecidual sejam detectados [22] . Então, optou-se em utilizar esse equipamento para poder avaliar de forma mais detalhada os efeitos dos materiais bioativos sobre a superfície de esmalte e dentina clareados.…”

“…Imagens semelhantes foram observadas em outra pesquisa feita por microscopia eletrônica de varredura por emissão de campo, que estudou o esmalte e dentina humana hígida em aumentos que variaram de 10.000 a 150.000x [22] .…”