Split crest technique for implant treatment of agenesis of the upper lateral incisors: results of a randomized pilot histological and clinical study at 24-month follow-up

Abstract Agenesis of lateral incisors, besides the functional issues, represents a great esthetic drawback. The selection of an appropriate treatment is a complex decision, which should consider the stability of the clinical outcomes over time. The aim of the present study was a histological and clinical comparison of two-stage split crest technique (SCT), with bone chips alone or mixed with porcine bone in patients affected by unilateral and bilateral agenesis of the upper lateral incisors. Eleven patients were enrolled, and randomly assigned to receive a treatment with autologous bone chips (group 1) or autologous bone chips mixed 1:1 to porcine-derived xenogenic bone (group 2). After a 2-month healing period, implants were placed and biopsies harvested for histomorphometrical evaluation. Clinical assessment, according to ICOI PISA health scale, and radiographic marginal bone loss evaluation at 12- and 24-month follow-ups were conducted. The histomorphometry showed significantly greater new bone formation (p > 0.0229) in group 2. At 12- and 24-month follow-ups, all the evaluated implants, regardless of the group they were allocated, could be categorized as "success" in the ICOI Pisa Health Scale for Dental Implants, and did not show significant difference in crestal bone loss. To the best of our knowledge, these are the first histological and clinical outcomes indicating that the use of bone chips mixed 1:1 to porcine bone in SCT could be a promising technique for the rehabilitation of patients with agenesis of the upper lateral incisors, although studies with a larger number of patients and implants, and a longer follow up are needed.

Influence of implant surfaces on osseointegration

The biological fixation between the dental implant surfaces and jaw bones should be considered a prerequisite for the long-term success of implant-supported prostheses. In this context, the implant surface modifications gained an important and decisive place in implant research over the last years. As the most investigated topic in, it aided the development of enhanced dental treatment modalities and the expansion of dental implant use. Nowadays, a large number of implant types with a great variety of surface properties and other features are commercially available and have to be treated with caution. Although surface modifications have been shown to enhance osseointegration at early implantation times, for example, the clinician should look for research evidence before selecting a dental implant for a specific use. This paper reviews the literature on dental implant surfaces by assessing in vitro and in vivo studies to show the current perspective of implant development. The review comprises quantitative and qualitative results on the analysis of bone-implant interface using micro and nano implant surface topographies. Furthermore, the perspective of incorporating biomimetic molecules (e.g.: peptides and bone morphogenetic proteins) to the implant surface and their effects on bone formation and remodeling around implants are discussed.

A fixação biológica entre as superfícies de implante e os ossos maxilares deve ser considerada como um pré-requisito para o sucesso em longo prazo de próteses implanto-suportadas. Neste contexto, as modificações nas superfícies de implante ganharam um lugar importante e decisivo na pesquisa em Implantodontia nos últimos anos. Sendo o tópico mais estudado, colaboraram para o melhoramento de modalidades de tratamento dental, assim como para a expansão de uso dos implantes dentais. Hoje, um grande número de diferentes implantes com uma grande variedade de propriedades de superfícies, entre outras características, está comercialmente disponível e isto deve ser tratado com cuidado. Apesar das modificações nas superfícies terem melhorado a osseointegração em tempos precoces de implantação, por exemplo, o clínico deve procurar evidências científicas antes de selecionar um implante dental para uso específico. Este artigo fará uma revisão da literatura sobre superfícies de implantes osseointegráveis, analisando estudos in vitro e in vivo, a fim de mostrar uma perspectiva atual do desenvolvimento dos implantes. Esta abordagem englobará os resultados obtidos com micro e nano topografias, em termos quantitativos e qualitativos, avaliando a interface osso-implante. Além disso, discutirá também as perspectivas da incorporação de substâncias biomiméticas (como peptídeos e proteínas morfogenéticas) à superfície dos implantes e seus efeitos na modulação da neoformação óssea periimplantar.