Comparison of osseointegration in piezoimplants versus cylindrical implants

BACKGROUND: Dental implants have been successful for the restoration of edentulous areas, but current techniques are inadequate in areas lacking sufficient bone volume. Piezoelectric surgery has shown encouraging effects on both osseous healing. A new wedge-shaped titanium PiezoImplant requires piezoelectric osteotomy. This study compares PiezoImplants to conventional threaded cylindrical shaped implants by microcomputed tomography and histology to assess osseointegration, tissue response, and alveolar ridge changes. METHODS: After 3 months post-extraction, 18 conventional cylindrical implants and 18 wedge-shaped PiezoImplants were placed using a split-mouth design in 3 adult mini pigs. The cylindrical implant sites were prepared for osteotomy with rotary instrumentation while the PiezoImplant sites were prepared with piezoelectric surgical inserts. One animal was sacrificed at 4, 8, and 12 weeks post operation. Quantitative µCT and histological analysis evaluated bone volume, osseointegration, and post-operative cellular events. RESULTS: The results of a multivariable linear regression model demonstrated that the PiezoImplants, arch location, and time were significant factors on higher BV/TV percentage. Bone to implant contact (BIC) analysis by high resolution microscopy and histomorphometry indicated osseointegration though intimate contact between implants and adjacent alveolar bone in both groups. The tissue response displayed no evidence of abnormal healing and the PiezoImplant was classified as a non-irritant. CONCLUSION: The combination of piezoelectric osteotomy and newly designed PiezoImplants had favorable effects on wound healing and osseointegration compared to conventional cylindrical implants. These novel wedge-shaped implants may be beneficial for narrow ridge spaces without additional ridge augmentation. Further research is needed to establish clinical validity

Platelet-rich plasma for regeneration of neural feedback pathways around dental implants: a concise review and outlook on future possibilities

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Psychosocial and quality of life outcomes of prosthetic auricular rehabilitation with CAD/CAM technology.

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Custom-made root analogue zirconia implants

O objectivo deste estudo foi conduzir uma revisão literária sobre os potenciais benefícios do uso de implantes dentários de zircónia customizados e análogos a estruturas radiculares. Uma pesquisa bibliográfica foi efectuada nas bases de dados Pub-Med e Science Direct desde 1969 a 2017. Foram explorados os seguintes itens de pesquisa: “zirconia” e “custom-made” e “dental implants”, “zirconia” e “root-analogue” e “dental implants”, “zirconia” e “anatomical” e “dental implants”, “zirconia” e “finite element” and “dental implants”, “zirconia” e ”customized” e “dental implants”, “zirconia” e “mechanical properties” e “dental implants”, “zirconia” e “biomechanical” e “dental implants”. Um total de 611 trabalhos foram selecionados a partir das bases de dados eletrónicas, sendo que um total de 81 foram preliminarmente selecionados para leitura completa. Um total final de 59 estudos foram selecionados para este estudo. Foi verificado pelos trabalhos selecionados que o uso de materiais à base de zirconia tem aumentado recentemente devido às suas propriedades estéticas e sucesso biológico. Além disso, os implantes análogos a estruturas radiculares estão-se a tornar uma solução viável para ultrapassar limitações relacionadas com distribuição de tensões ao osso peri-implantar, estética e peri-implantite por acúmulo de biofilme. Além disso, os avanços tecnológicos recentes têm levado a novas estratégias para melhorar a morfologia e superfícies dos implantes de zircónia. Entretanto, poucos estudos ainda são encontrados para os implantes análogos a estruturas radiculares e ainda torna-se difícil a comparação de resultados dentre inúmeras geometrias e condições intrínsecas dos pacientes.The aim of this study was to conduct a literature review on the potential benefits of custom-made root analogue zirconia implants. A PubMed and ScienceDirect bibliographical search was carried out from 1969 to 2017. The following search items were explored: “zirconia” and “custom-made” and “dental implants”, “zirconia” and “root-analogue” and “dental implants”, “zirconia” and “anatomical” and “dental implants”, “zirconia” and “finite element” and “dental implants”, “zirconia” and “customized” and “dental implants”, “zirconia” and “mechanical properties” and “dental implants”, “zirconia” and “biomechanical” and “dental implants”. The increased interest in zirconia-based dental structures linked to aesthetic and biological outcomes have been reported in literature. Also, custom-made root analogue implants have become a viable alternative to overcome limitations concerning stress distribution, aesthetics and peri-implantitis induced by biofilms. Recent technological advances have focused on novel strategies to modify zirconia-based surfaces to accelerate osseointegration. However, only a few studies revealed mechanical and biological benefits of zirconia custom-made root analogue implants and therefore further studies should investigate the influence of different geometries and surface modification on the performance of such implants

A retrospective evaluation of vertical bone loss around dental implants following immediate placement and immediate loading.

The immediate placement and loading of dental implants has many advantages and is an on-going focus of interest and research. Identifying factors that decrease vertical bone loss associated with implants might improve the prognosis of this protocol. This report evaluated survival (defined as the implant being present at the last review of the patient) and success (determined by the vertical bone loss around an implant) of immediately placed and loaded dental implants. Moreover, it set to determine whether site of placement and implant length had any influence on survival and vertical bone loss and thus have predictive value when immediately placing and loading a dental implant. The study was a retrospective clinical study consisting of a series of patients from an Oral and Maxillofacial surgeon’s private practice. Forty implants in 17 patients were analysed by comparing orthopantomographic radiographs taken immediately post placement and at the final review visit. Survival was determined for the sample and within the 2 parameters mentioned (i.e. implant length and placement site). Bone levels were measured on the radiographs of the subject concerned. Distortion and variance of the radiograph machine was calculated and all measurements corrected for distortion. The rate of bone loss and survival was determined for the sample. Success, or vertical bone loss, was judged by the rate of vertical bone loss measured for the entire sample and also within the two parameters. Four sites of placement were assessed, anterior maxilla, posterior maxilla, anterior mandible and posterior mandible. Two implant lengths were assessed, < 15mm and ≥ 15mm. The results were then analysed for significance to see if site of placement or length of implant influenced survival or vertical bone loss around the implant. There were no implant losses and therefore survival was 100%. The average rate of bone loss for the sample was 0.80mm per annum, which is within the internationally accepted norm of 1.5mm in the first year of placement. As survival was 100%, no statistical analysis was done for this parameter. There were statistically significant differences in the rate of bone loss with regards to the site that an implant was placed. The rate of loss was highest in the posterior maxilla, followed by the anterior mandible and then the posterior mandible. The anterior maxilla had the lowest rate of bone loss. Implant lengths of 15mm or longer had a statistically significant, higher rate of bone loss than implants shorter than 15mm. This study concludes that different implant sites have different success outcomes and that immediately placed and loaded implants, placed in the anterior maxilla, will be associated with less marginal bone loss. Similarly, with respect to implant length, implants shorter than 15mm enjoyed diminished bone loss. These results are expected in some aspects (i.e. survival and rate of bone loss of the sample as a whole), but are unusual in others (i.e. the rate of bone loss in the anterior maxilla being lower than traditionally more predictable sites, and rate of bone loss being less in shorter implants). It could be attributed to inherent difficulty in accurately assessing images in the anterior maxilla on an orthopantomographic radiograph, which would explain the results with respect to site of placement, or a number of flaws in the design of the study. These assumptions are made empirically, as no study I am aware of has specifically compared vertical bone loss within parameters of length and site

Biomechanical aspects in dental replacements

This chapter deals with biomechanical aspects in dental replacements. The state of the art is critically reviewed taking into account the body of the literature results. The initial section is devoted to the mechanical properties of bone and to a description of the jaw geometry and of its loading and constraining. The following section presents a classifi cation of the various tooth replacement confi gurations and of the various materials adopted, where single and multiple replacements are considered. A specifi c section is devoted to the solid modelling of the jaw as input to numerical analyses, where the aid offered by reverse engineering and tomography is underlined. The fi nite element method as well as alternative numerical and experimental approaches are reviewed in a dedicated section. The stress analysis forecasts and measurements are biomechanically interpreted in the light of the current literature results. The chapter ends with a section devoted to biological aspects

Applications of 3D printing in the management of severe spinal conditions

The latest and fastest-growing innovation in the medical field has been the advent of three-dimensional printing technol- ogies, which have recently seen applications in the production of low-cost, patient-specific medical implants. While a wide range of three-dimensional printing systems has been explored in manufacturing anatomical models and devices for the medical setting, their applications are cutting-edge in the field of spinal surgery. This review aims to provide a com- prehensive overview and classification of the current applications of three-dimensional printing technologies in spine care. Although three-dimensional printing technology has been widely used for the construction of patient-specific ana- tomical models of the spine and intraoperative guide templates to provide personalized surgical planning and increase pedicle screw placement accuracy, only few studies have been focused on the manufacturing of spinal implants. Therefore, three-dimensional printed custom-designed intervertebral fusion devices, artificial vertebral bodies and disc substitutes for total disc replacement, along with tissue engineering strategies focused on scaffold constructs for bone and cartilage regeneration, represent a set of promising applications towards the trend of individualized patient care

Evolution of design considerations in complex craniofacial reconstruction using patient-specific implants

Previously published evidence has established major clinical benefits from using Computer Aided Design (CAD), Computer Aided Manufacturing (CAM), and Additive Manufacturing (AM) to produce patient-specific devices. These include cutting guides, drilling guides, positioning guides, and implants. However, custom devices produced using these methods are still not in routine use – particularly by the UK National Health Service (NHS). Oft-cited reasons for this slow uptake include: a higher up-front cost than conventionally-fabricated devices, material-choice uncertainty, and a lack of long-term follow-up due to their relatively recent introduction. This paper identifies a further gap in current knowledge – that of design rules, or key specification considerations for complex CAD/CAM/AM devices. This research begins to address the gap by combining a detailed review of the literature with first-hand experience of interdisciplinary collaboration on five craniofacial patient case-studies. In each patient case, bony lesions in the orbito-temporal region were segmented, excised, and reconstructed in the virtual environment. Three cases translated these digital plans into theatre via polymer surgical guides. Four cases utilised AM to fabricate titanium implants. One implant was machined from PolyEther Ether Ketone (PEEK). From the literature, articles with relevant abstracts were analysed to extract design considerations. 19 frequently-recurring design considerations were extracted from previous publications. 9 new design considerations were extracted from the case studies – on the basis of subjective clinical evaluation. These were synthesised to produce a design considerations framework to assist clinicians with prescribing and design engineers with modelling. Promising avenues for further research are proposed

Implantes en arbotantes anatómicos del maxilar superior

El cráneo posee una serie de arbotantes de hueso denso que forman un armazón protector en torno a las múltiples cavidades craneofaciales. El tercio medio posee dos arbotantes anteriores (frontomaxilar y frontocigomático) y uno posterior (pterigomaxilar). Estos permiten, en algunas situaciones, la rehabilitación de extremos libres superiores en maxilares atróficos mediante la colocación de implantes con una angulación parasinusal, evitando así la utilización de técnicas más complejas como la elevación sinusal o la reconstrucción mediante autoinjerto. En este trabajo se ha realizado una revisión bibliográfica sobre la inserción de implantes en arbotantes anatómicos en el maxilar superior.The skull presents a series of dense bony buttresses that conform a protective frame around the different craniofacial cavities. The middle third portion presents two anterior buttresses (frontomaxillary and frontozygomatic) and a posterior buttress (pterygomaxillary). In certain situations these structural supports allow the rehabilitation of free upper extremities in atrophic jaws by positioning parasinusal angulated implants ' thereby avoiding the need for more complex reconstruction techniques such as sinus lifting or autografting procedures. The present study presents a review of the literature on implant insertion in anatomical buttresses of the upper jaw

Pilot study: evaluation of the use of the convergent interview technique in understanding the perception of surgical design and simulation

BACKGROUND: It is important to understand the perceived value of surgical design and simulation (SDS) amongst surgeons, as this will influence its implementation in clinical settings. The purpose of the present study was to examine the application of the convergent interview technique in the field of surgical design and simulation and evaluate whether the technique would uncover new perceptions of virtual surgical planning (VSP) and medical models not discovered by other qualitative case-based techniques. METHODS: Five surgeons were asked to participate in the study. Each participant was interviewed following the convergent interview technique. After each interview, the interviewer interpreted the information by seeking agreements and disagreements among the interviewees in order to understand the key concepts in the field of SDS. RESULTS: Fifteen important issues were extracted from the convergent interviews. CONCLUSION: In general, the convergent interview was an effective technique in collecting information about the perception of clinicians. The study identified three areas where the technique could be improved upon for future studies in the SDS field