Reliability of Linear and Curvilinear Measurements on Cone-Beam Computed Tomography Images for the Evaluation of Implant Sites and Jaw Pathologies

ABSTRACT Objective: To evaluate the intra-examiner and inter-examiner reliability of linear and curvilinear measurements for the complete assessment of implant sites and jaw pathologies using Cone-Beam Computed Tomography (CBCT). Material and Methods: Fifty cone-beam computed tomographic images of patients were retrieved from the archives of Dentomaxillofacial Radiology. CBCT images taken for implant planning and evaluation of intrabony jaw pathologies (benign cyst/tumor) were included. Two expert oral and maxillofacial radiologists analyzed the images independently and made the measurements. The images for implant planning were analyzed for width, the height of the edentulous site, and the qualitative analysis of bone in the region. Jaw pathologies were assessed for linear dimensions and curvilinear measurements. Results: The inter-observer measurement error for implant site analysis ranged from 0.12 to 0.42 mm with almost perfect agreement (ICC: 0.94 to 1). The inter-observer measurement error for jaw pathology was 0.09 to 0.25 mm (ICC: 0.98-1). Curvilinear measurements showed perfect agreement between the observers. The intraobserver reliability for the various parameters used for the assessment of the implant site and jaw pathologies indicated almost perfect agreement. Conclusion: Reliability between the radiologists is high for various measurements on CBCT images taken for implant planning and jaw pathologies.

Evaluation of Masticatory Performance and Patient Satisfaction Before and After Posterior Implant Restoration

ABSTRACT Objective: To evaluate the improvement in masticatory performances two weeks after posterior implant restoration. Material and Methods: Nine patients with missing first and second molars were included in the study. Masticatory performances were evaluated using subjective and objective methods utilizing color-changeable chewing gum and the visual analog scale (VAS) assessment. The subjects were asked to chew the color-changeable chewing gums before and two weeks after the posterior implant restoration. Their expectations regarding aesthetics and function were verified on the VAS before implant placement. Additionally, the VAS was used for the posttreatment completion rating two weeks after the implant restoration. Results: Significant differences in masticatory performance were noted at baseline (before implant posterior restoration) and two weeks after implant restoration (p<0.05). The posttreatment aesthetic and functional expectations ratings significantly exceeded the expectations (p<0.05). Conclusion: Masticatory performances were improved two weeks after implant restoration. In addition, the significant posttreatment ratings of the patients exceeded their initial expectations. In particular, patients with poor masticatory functions demonstrated significant improvements and satisfaction following implant restoration compared to those with good mastication. These findings indicate that a posterior implant restoration can increase the masticatory performance.

Evaluation of the long-term stability of micro-screws under different loading protocols: a systematic review

Abstract: The aim of this systematic review was to investigate the association between the different factors of loading protocols and the long-term stability of micro-screws from biomechanical and histological viewpoints. Searches were performed on PubMed, Embase, Cochrane Library, Wanfang and CNKI databases for animal experiments comparing loading protocols and the long-term stability of micro-screws. Among 1011 detected papers, 16 studies met the eligibility criteria and were selected for analysis. Most studies showed medium methodological quality for evaluation of micro-screws' long-term stability. Five studies reported that loading would not destroy the long-term stability of micro-screws. Three studies indicated that low-intensity immediate loading or a 3-week minimal healing time was acceptable. Two studies reported that the loading magnitude was a controversial issue with regard to the micro-screws' long-term stability. Two studies suggested that counterclockwise loading could decrease the long-term stability of micro-screws. In conclusion, immediate loading below 100g force, healing time greater than 3 weeks, regular loading below 200g force and a clockwise direction of force supported the long-term stability of micro-screws. Further studies relating to the combination of varying loading conditions will be needed.

Mini-implant selection protocol applied to MARPE

Abstract Introduction: Rapid maxillary expansion (RME) is the therapy of choice to correct skeletal transverse dimension in children and adolescents, associating orthopedic and dental effects. In an attempt to prevent the undesirable dentoalveolar effects and optimize the potential of skeletal expansion in individuals in advanced stages of skeletal maturation, the miniscrew-assisted rapid palatal expander (MARPE) was proposed by Lee et al. in 2010. Objective: This paper presents a systematized protocol for selection of miniscrews indicated for MARPE, by the evaluation of cone-beam computed tomographies (CBCT). Variables related with the bone and soft tissue thicknesses at the palatal regions of interest, as well as in relation to the fixation rings of miniscrews of the palatal expander are analyzed and discussed to provide better performance in the clinical practice.

Resumo Introdução: a expansão rápida da maxila (ERM) é a terapia de escolha para a correção da dimensão transversa esquelética em crianças e adolescentes, associando-se efeitos ortopédicos e dentários. Com a finalidade de prevenir os efeitos dentoalveolares indesejáveis e otimizar o potencial de expansão esquelética em indivíduos com estágios avançados de maturação esquelética, a técnica de expansão rápida da maxila assistida por mini-implantes (MARPE) foi proposta por Lee e colaboradores em 2010. Objetivo: o presente estudo apresenta um protocolo sistematizado para seleção de mini-implantes indicados para a MARPE, mediante avaliação de imagens de tomografia computadorizada de feixe cônico (TCFC). Variáveis relacionadas à espessura de tecido ósseo e tecido mole nas regiões de interesse do palato, bem como em relação ao anel de fixação dos mini-implantes do parafuso expansor, são analisadas e discutidas para proporcionar melhor desempenho na prática clínica.

Influência do alinhamento das imagens por TCFC nas medidas lineares virtuais das relações entre implantes dentários: estudo laboratorial / The influence of different CBCT image alignment position on the virtual linear measurements of dental implant relationships: a laboratory study

Objetivo: verificar a variação das medidas lineares em função de angulações distintas dos implantes e dos alinhamentos diferentes das imagens de TCFC. Material e métodos: três mandíbulas artificiais de polietileno receberam 18 implantes dentários, com seis implantes em cada mandíbula, sendo: 1) dois angulados no sentido distal no lado direito posterior, 2) um angulado para vestibular e outro para lingual na região anterior, e 3) dois angulados no sentido mesial na região posterior esquerda. Com a mandíbula apoiada na mentoneira do equipamento e paralela ao plano horizontal, foram realizadas três aquisições tomográficas padronizadas, (voxel de 0,133 mm, FOV 6 x 8 cm, 89kV, 10 mA). Depois, foram realizadas uma medida perpendicular (da plataforma do implante ao rebordo mandibular) e outra inclinada (da plataforma do implante ao longo eixo do rebordo) nos cortes coronais e sagitais. As medidas foram realizadas com a base de mandíbula paralela ao plano horizontal e também após o volume ser rotacionado para o inferior no plano sagital. Os implantes foram numerados de um a seis e divididos em duplas. As medidas foram comparadas antes e após o alinhamento das imagens através do programa OnDemand3D. Resultados: foram observadas diferenças estatisticamente significantes entre as medidas realizadas nos implantes 1 e 2. Conclusão: as medidas lineares sofreram alteração em decorrência do posicionamento mandibular quando manipulado em software.

Objective: to verify the linear measure variation according to the distinct implants angulations and the different alignment from CBCT images. Material and methods: three polyethylene artifi cial models received 18 dental implants, 6 in each jaw, being: 1) two angled to distal on the right posterior side, 2) one angled to vestibular and another to lingual on the anterior region, 3) two angled to mesial way on the left posterior region. Each jaw was supported at a chinstrap of the equipment and parallel to the horizontal plane, and three standardized tomographic acquisitions were taken, (voxel size 0.133 mm, FOV 6 x 8 cm, 89kV, 10 mA). A perpendicular measure was made after the tomographic acquisitions (from the implant platform to the jaw border) and another inclined measure (from the implant platform to border long axis) both on coronal and sagittal acquisitions. Measurements were taken with the jaw base parallel to the horizontal plane and also when the volume was rotated to inferior on the sagittal plane. The implants were numbered from one to six and divided into couples. The measures were compared before and after image alignment by the OnDemand3D software. Results: statistically signifi cant differences were observed between the measurements performed on implants 1 and 2. Conclusion: the linear measurement values change in consequence of the jaw position when manipulated by the software.

Study of the relationships between bur diameter and dental implant diameter / Estudio de las relaciones entre diámetro de fresas y diámetro de implantes dentales

The bur used to construct the bed where a dental implant is installed is extremely important to treatment success. The aim of this investigation was to analyze the relationship between bur diameter and implant diameter in different areas. A descriptive study was designed to analyze 5 commercial brands currently on the market. The manufacturer's instructions were followed to establish the size and type of bur indicated for the study implants, which were regular, with a width between 3.5 mm and 4.0 mm and a length from 12 mm to 13 mm. Drilling from the most apical region, the first measurement of width was established 3 mm cervically, the lower middle measurement 6 mm cervically, the upper middle measurement at 9 mm and the cervical measurement at 12 mm. A scanning electron microscope was used standardized for all measurements; the data were analyzed using the Shapiro-Wilk test and the t-test, having considering a value of p<0.05 for significant differences. At apical level, all the implants were wider than the bur. The greatest differences between bur width and implant were observed at cervical level, maintaining a relation where the implant was always wider. In medium-sized areas, it was observed that in some systems the burs have a larger diameter than the study implants. A significant relation was established in the apical, upper middle and cervical areas. Bur morphology is related to implant morphology; no implant system is the same as another in terms of the implant-bur relation.

La relación entre la fresa utilizada para construir el lecho donde se instala el implante dental tiene alta importancia en el éxito del tratamiento. El objetivo de esta investigación fue analizar la relación entre el diámetro de fresa y el diámetro de implantes en diferentes áreas. Se diseñó un estudio descriptivo analizando utilizando 5 marcas comerciales vigentes en el mercado; se siguió las instrucciones del fabricante para establecer el tamaño y tipo de fresa indicada para el implante en análisis, los cuales fueron de tipo regular considerando medidas en ancho de entre 3,5 mm y 4,0 mm y en largo de 12 mm a 13 mm. Desde la región mas apical de implantes y fresar se estableció 3 mm hacia cervical la primera medición de ancho, 6 mm hacia cervical la medición media inferior, a 9 mm la medición media superior y a 12 mm la medición cervical; para esta medición se utilizó microscopio electrónico de barrido estandarizado para todas las mediciones; los datos fueron analizados con pruebas estadísticas de Shapiro-Wilk y la prueba t-test, considerando un valor de p<0,05 para considerar diferencias significativas. A nivel apical, todos los implantes fueron mas anchos que las fresas utilizadas. A nivel cervical es donde se observan las mayores diferencias entre el ancho de la fresa y del implante manteniendo una relación donde el implante siempre es mas ancho. En áreas medianas, se observó que en algunos sistemas las fresas son de mayor diametro a los implantes analizados. Se estableció relación significativa en las regiones apical, media superior y cervical. La morfología de fresas presenta relación con la morfología implantaría; ningún sistema de implantes es igual a otro en términos de relación implante y fresa.

Biomateriales en levantamiento de seno maxilar para implantes dentales / Biomaterials in maxillary sinus lift for dental implants

RESUMEN: Objetivos El objetivo principal es describir las técnicas y condiciones en que se usan los diferentes biomateriales para los procedimientos de aumento del seno maxilar en implantes oseointegrados inmediatos o diferidos. Método Se realizó una búsqueda electrónica de textos completos desde el año 2010 hasta el 15 de agosto del 2014, y que respondieran la pregunta de investigación, utilizando diferentes buscadores y una manual en las revistas científicas de periodoncia. Se determinó el nivel de evidencia, calidad de reporte, sesgos de la literatura analizada y aspectos éticos. Resultados Se seleccionaron 17 estudios, 4 revisiones sistemáticas y 13 ensayos clínicos aleatorizados. Diez estudios comparaban los diferentes biomateriales disponibles entre sí, y no encontraron diferencias estadísticamente significativas en la nueva formación ósea. Un estudio examinaba la opción de no utilizar un biomaterial en el aumento de senos maxilares. Seis estudios indicaban que el uso de biomateriales adicionales no era significativo. Tres estudios concluyeron que no existían diferencias significativas entre uno o 2 tiempos quirúrgicos para realizar los procedimientos. Tres estudios comparaban la técnica quirúrgica de ventana lateral con la técnica indirecta, sin encontrar diferencias estadísticamente significativas, pero sí se asocia a un menor número de complicaciones a la técnica indirecta, especialmente al estar acompañada de la instalación de implantes cortos. Conclusiones No se describen diferencias entre los diferentes biomateriales utilizados en procedimientos de aumento de senos maxilares. El uso de biomateriales adicionales pareciera no ofrecer beneficios medibles al tratamiento. La técnica quirúrgica indirecta puede ser asociada a un menor número de complicaciones. Son necesarios más estudios de ensayos clínicos aleatorizados, con tamaños de muestra mayores, variables controladas y seguimientos a largo plazo para establecer conclusiones.

ABSTRACT: Objectives The main objective is to describe the techniques and conditions in which the various biomaterials are used for sinus augmentation procedures for immediate or delayed osseointegrated implants. Method An electronic search was conducted looking for papers published from 2010 to 15 August 2014 to answer the research question. Several search engines were used as well as a manual on scientific journals of periodontics. The level of evidence, quality reporting, biases of the analysed literature, and ethical aspects were determined. Results A total of 17 studies were selected, of which 4 were systematic reviews, and 13 were randomised trials. Ten different trials compared the available biomaterials with each other, and found no statistically significant differences in new bone formation. One study examined the option of not using biomaterials in the procedures. Six studies indicated that the use of additional biomaterials was not significant. Three studies concluded that there were no significant differences between 1 and 2 surgical times. Three studies compared the surgical technique of lateral window with the indirect technique, with no statistically significant differences, but the indirect technique was associated with fewer complications, especially when accompanied by the installation of short implants. Conclusions No differences between different biomaterials used in augmentation procedures for maxillary sinuses were described. The use of additional biomaterials does not seem to offer measurable benefits to the treatment. The indirect surgical technique may be associated with fewer complications. Further studies of randomised clinical trials, with larger sample sizes, controlled variables, and long term monitoring are needed to draw stronger conclusions.

Substituição dentária conservadora utilizando implantes e o dente pré-existente para provisórios estéticos / Conservative tooth replacement using implants and pre-existing tooth for aesthetic provisional restorations

Objetivo: apresentar, através de um caso clínico, a utilização de coroas de dentes extraídos como provisórios em próteses fixas unitárias maxilares anteriores, favorecendo aspectos como estética, conforto psicológico, perfil de emergência, biocompatibilidade com tecidos moles e durabilidade em relação a provisórios fixos convencionais. Características do paciente: alta demanda estética, apresentando incisivos centrais maxilares com indicação de substituição por implantes, mas com estética coronária satisfatória. Tratamento propriamente dito: através de desgaste seletivo da coroa original, cobertura do intermediário metálico com resina opaca e preenchimento com resina flow, foi possível a utilização das coroas originais da paciente como provisórios imediatos. Conclusão: a utilização de coroas fixas implantossuportadas construídas a partir de coroas naturais pode melhorar aspectos estéticos, biológicos e psicológicos do tratamento, quando corretamente indicadas e aplicadas.

Objective: to present a case report of the use of extracted teeth as provisional crowns in fixed maxillary prosthesis, favoring aesthetics, psychological comfort, emergency profile, soft tissue biocompatibility and durability in relation to conventional fixed prosthesis. Patient characteristics: patient with high aesthetic demand, presenting maxillary central incisors with indication for replacement with implants, but with satisfactory dental aesthetics. Proposed treatment: through selective wear of the original crown, coating of the metallic abutment with opaque resin and filling with flow resin, it was possible the use of the patient's original crowns as immediate prosthesis. Conclusion: the option to use implantsupported fi xed crowns constructed from natural crowns can help patients with aesthetic, biological and psychological aspects of the treatment, as long as correctly indicated and applied.

Accuracy of resonance frequency analysis by third generation Osstell® / Precisión del análisis de frecuencia de resonancia mediante Osstell® de tercera generación

The Resonance Frequency Analysis by Osstell® is used in the assessment of primary and secondary implant stability. The aim of this study was to determine its accuracy as a method of testing, checking its repeatability and reproducibility. A pilot study was performed whereby implants were placed in a cow rib to compare several ISQ measurements with the same SmartPeg transducer (repeatability), or with different SmartPegs (reproducibility). Statistical analysis of the data showed a high correlation of the ISQ values obtained in both assays, which suggests that Osstell®analysis can provide high repeatability and reproducibility.

El análisis de frecuencia de resonancia (AFR) por Osstell® se utiliza en la evaluación de la estabilidad primaria y secundaria del implante. El objetivo del presente estudio fue establecer la precisión del AFR mediante Osstell©, como método de prueba empleado en la determinación de la estabilidad implantaria. Se realizó un estudio experimental in vitro, en el que se colocaron implantes en una costilla de vaca y compararon diferentes mediciones del coeficiente de estabilidad del implante (ISQ) obtenidas sobre estos implantes con un mismo transductor SmartPeg (repetibilidad) o con diferentes SmartPegs (reproductibilidad). El análisis estadístico de los datos mostró una elevada correlación de los ISQ obtenidos en ambos ensayos, lo cual sugiere una reproductibilidad y repetibilidad elevada del análisis mediante Osstell.

Conexão dente-implante: uma alternativa viável? Relato de Caso Clínico usando prótese parcial removível apoiada sobre dentes e implantes / Connection tooth-implant: a viable alternative?Case report using removable partial denture supported on teeth and implants

As fissuras labiopalatinas levam os profissionais a idealizarem próteses não convencionais na busca da solução das reabilitações por se tornarem, muitas vezes, bastante complexas. Próteses totalmente implanto-suportadas devem ser o tratamento de escolha, embora haja casos em que a união de dentes com implantes é inevitável. Há autores que defendem a união rígida, outros a não rígida e outros ainda que não recomendem a união dente-implante. Os riscos relacionados a esta união são resultado de diferenças biomecânicas entre as estruturas envolvidas, ligamento periodontal e osso, e da biomecânica dos dentes e implantes apoiados sobre as próteses. Objetivo: este trabalho relata um caso clínico de reabilitação oral com uma PPR sobre dentes unidos a implantes em uma paciente com fissura labiopalatina do Hospital de Reabilitação de Anomalias Craniofaciais de Bauru. Método: relato do caso. Resultados e Discussão: paciente de 47 anos, gênero feminino, portadora de fissura pós-forame incisivo incompleta, apresentava os dentes 13, 23 e 27, sendo este extraído por problemas periodontais, e 2 implantes instalados nas regiões dos dentes 16 e 26. O planejamento reabilitador protético foi a instalação de uma PPR com encaixe tipo barra-clip retida por 3 barras metálicas unindo os dentes aos implantes por meio de um sistema tubo parafuso. A união não-rígida demonstra maior distribuição das forças, embora possa causar a intrusão dentária. Já a união rígida, apresenta maior estresse e maior perda óssea na região dos implantes. Conclusão: o correto planejamento, embasado na biomecânica, assim como controles clínicos e rádio gráficos posteriores, são de suma importância para o sucesso do tratamento reabilitador protético...

Cleft lip and palate lead professionals to idealize unconventional prostheses to find the solution for the rehabilitation that becomes, oftentimes, complex. Totally implant-supported prostheses should be the treatment of choice, although there are cases in which the connection of teeth with implants is inevitable. Some authors advocate the rigid connection, others the non-rigid connection and still others do not recommend the implant-tooth connection. The risks related to this connection are the result of biomechanical differences between the structures involved, periodontal ligament and bone, and biomechanics of teeth and implants supported on the prostheses. Objective: this report presents a case of oral rehabilitation with a removable partial prosthesis on teeth connected to implants in a patient with cleft lip and palate in Hospital of Rehabilitation of Craniofacial Anomalies of Bauru. Method: case report. Results and Discussion: a 47 year old female patient, with incomplete post foramen cleft presenting the teeth 13, 23 and 27, which was extracted by periodontal problems, and two implants placed in regions of the teeth 16 and 26. The prosthetic rehabilitation treatment was the installation of a removable partial prosthesis with a bar-clip type of fit retained by 3 metal bars connecting teeth to implants through a tube screw system. The non-rigid connection demonstrates greater distribution of forces, although it can cause tooth intrusion...

Screw loosening of different UCLA-type abutments after mechanical cycling

AIM: To evaluate the loss of applied torque (detorque) values in cast and pre-machined abutments for external hex abutment/implant interface of single implant-supported prostheses subjected to mechanical cycling. METHODS: Ten metal crowns were fabricated using two types of UCLA abutments: cast and pre-machined with metal base in NiCrTi alloy and tightened to regular external hex implants with a titanium alloy screw, with an insertion torque of 32 N.cm, measured with a digital torque gauge. Samples were embedded with autopolymerizing acrylic resin in a stainless steel cylindrical matrix, and positioned in an electromechanical machine. Dynamic oblique loading of 120 N was applied during 5 x 10(5) cycles. Then, each sample was removed from the resin and detorque values were measured using the same digital torque gauge. The difference of the initial (torque) and final (detorque) measurement was registered and the results were expressed as percentage of initial torque. The results of torque loss were expressed as percentage of the initial torque and subjected to statistical analysis by the Student's t-test (p<0.05) for comparisons between the test groups. RESULTS: Statistical analysis demonstrated that mechanical cycling reduced the torque of abutments without significant difference between cast or pre-machined UCLA abutments (p=0.908). CONCLUSIONS: Within the limitations of this in vitro study, it may be concluded that the mechanical cycling, corresponding to one-year use, reduced the torque of the samples regardless if cast or pre-machined UCLA abutments were used.

Rehabilitación sobre implantes oseointegrados / A case with rehabilitation on boneintegrated implants

Se presenta un caso de un paciente rehabilitado en la consulta de Implantología de la Facultad de Estomatología de Ciudad de La Habana. La historia de la implantología moderna se remonta a principios de los años 60, cuando Per-Ingvar Branemark sienta las bases de la osteointegración y describe los primeros implantes de titanio con forma de tornillo. Aunque antigua, es la prótesis más moderna. Si la meticulosidad es obligada en la elaboración de todo tipo de prótesis, en los trabajos de implantes no se admite el más mínimo fallo, desde la planificación del caso hasta la implantación de la prótesis en boca. Para obtener buenos resultados, las técnicas y los procesos han de observarse escrupulosamente. En nuestra Facultad se ha creado el Grupo de Implantología, que es el encargado de la colocación de implantes y la rehabilitación prótesica de estos. Para ello han sido utilizado diferentes tipos de implantes comercializados y patentizados al nivel mundial. Se reafirma que la rehabilitación sobre implantes mejora la calidad estética y funcional de los pacientes(AU)

A case of rehabilitation patient is presented seen in Implantation Science consulting room of Stomatology Faculty of Havana City. History of implantation science dates back to at the beginning of 60s, when Per-Ingvar Branemark creates the bases of bone-integration and to describe the firsts titanium implants in a screw form. Although ancient, it is the more modern prosthesis. If meticulousness if mandatory in elaboration of all type of prosthesis, in implants works it inadmissible the minimum of failure, from the case planning until prosthesis implantation in mouth. To achieve good results, techniques and processes has to be scrupulously observed. In our Faculty it has been created a group of Implantation Science, which is in charge of implants placement, and of the prosthetic rehabilitation of these. Thus, we used different types of marketed and showed at world level. It is confirmed that rehabilitation on implants improves aesthetic and functional quality of patients(AU)

Recuperación de la morfología y fisiología maxilo mandibular: biomateriales en regeneración ósea / Maxillomandibular morphology and phisiology recovery: biomaterials in bone regeneration

Las caries dentales y la enfermedad periodontal son un problema de salud pública. En Chile, el 100 por ciento de la población de NSE medio - bajo y bajo presenta caries, con índices más altos en la IX Región. El 92.19 por ciento de las personas entre 35 y 74 años presentan periodontitis. Ambas enfermedades pueden llevar a que el paciente pierda sus dientes. Existen técnicas que mejoran el pronóstico de tratamientos protésicos, tales como los implantes de titanio, que pueden requerir aumentar la cantidad de hueso para reestablecer la forma y función. Se muestra una revisión de la literatura sobre biomateriales en regeneración ósea. El biomaterial con mejores propiedades es el hueso autólogo (AI), sin embargo, existen alternativas, aloinjerto (AL) y matrices óseas. Los AI poseen mejor pronóstico, los de origen endocondral (EC) e intramembranoso (IM) con un 357 por ciento y un 642 por ciento más formación ósea que un AL de tipo IM (6). Los AI IM son más exitosos que los EC (IM 166 por ciento más neoformación ósea). La disponibilidad de AI es limitada, por lo que es necesario utilizar biomateriales. AL mezclado con matriz ósea produce un 224 por ciento más hueso que AL IM solo. La utilización de membranas mejora la estabilidad a largo plazo de hueso IM y EC. AI EC son los biomateriales más exitosos. Dada su baja disponibilidad, pueden ser usados en conjunto con matrices. Las membranas han mostrado aumentar la estabilidad de los biomateriales.

Dental caries and periodontal disease are public health problems. 100 percent of people from low-medium and low socio economic levels have caries. 92.19 percent of people between 35 and 74 years of age have periodontal disease. Both pathologies may cause teeth fall down. Titanium implants could improve prognosis of prosthetics treatments, but frequently requires increase bone volume, to restore shape and function. The research wants to know state of art in use of biomaterials in bone regeneration. Best biomaterial properties were shown by autologous bone (AB), however, do exist alternatives such as allograft (AL) and bone matrix (BM). AB has shown best prognosis, from endochondral (EC) and intramembranous (IM), with 357 percent and 642 percent most bone formation compared to AL IM. AB IM type is successfully compared to EC (IM shown 166 percent more bone formation). AB access is limited, this fact have made necessary use other biomaterials. AL combined with BM produce 224 percent more bone compared to AL. Membrane use improves long term stability of IM and EC bone. AB EC type is the most successful biomaterial. Considering limited access to this bone, it could be used combined with bone matrix. Membranes have shown increase long term stability of biomaterials.

Length determination of zygomatic implants using tridimensional computed tomography / Determinação do comprimento de fixações zigomáticas a partir de tomografia computadorizada tridimensional

Considering the potential of tridimensional computed tomography (3D-CT) as a predictor of real bone dimensions, nine dried human skulls with maxillary edentulism were evaluated using images obtained by 3D-CT, prior to the installation of zygomatic implants, in order to obtain the measurements of the implants. In the analysis of correlation between the two 3D-CT examiners, a 75 percent agreement was found, and no correlation was found between them and the surgical measurement. The worst result was the surgical one, possibly because an inaccurate probe was used. Based on the obtained data, we concluded that the probe used is inaccurate, suggesting that the surgical probe be changed in its measurement scale. Agreement between surgeon and radiologist could possibly be obtained by using insertion guides, since what might have possibly caused the discrepancy in the results is the fact that the 3D-CT examiners and the surgeon used different implant insertion points. It is also possible that a larger sample might produce a more accurate evaluation, thus improving the results.

Considerando-se o potencial da tomografia computadorizada tridimensional (TC-3D) como preditor de dimensões ósseas reais e avaliando-se nove crânios humanos secos com edentulismo maxilar, foi feito um estudo utilizando-se o recurso das imagens obtidas por TC-3D, previamente à execução da técnica de fixação zigomática, para mensurar o comprimento de tais fixações. Na avaliação da concordância interexaminador da TC-3D, houve uma boa correlação entre o primeiro e segundo (75 por cento), e ausência de correlação entre estes e a medida cirúrgica. Contextualizando, o pior resultado foi o cirúrgico, possivelmente pelo fato de utilizar uma sonda imprecisa. Diante dos dados obtidos, concluiu-se que a sonda utilizada é imprecisa, sugerindo uma mudança na mesma quanto ao seu escalonamento e que medidas para aproximar as linguagens do cirurgião e do radiologista talvez fossem conseguidas com a utilização de guias de inserção, pois o que possivelmente ocasionou a discrepância nos resultados foi o fato de os examinadores 1 e 2 da TC-3D medirem um local de inserção da fixação e o cirurgião inserir esta em outro. É possível que uma amostra maior, por proporcionar avaliações mais abrangentes, possa incrementar os resultados ora encontrados.