A oclusão nas próteses totais implantossuportadas mediatas e imediatas

Rehabilitation of edentulous patients has been a challenge for professionals since the primary concepts and fundaments of occlusal rehabilitation. However, this philosophy has been improved by implant-supported fixed dentures that represent a predictable clinical modality on modern dentistry. Nevertheless, considering that the traditional protocol requires a long period for bone healing and definitive rehabilitation, immediate loading of implants has been advantageous for functional and esthetic rehabilitation of patients in a reduced period. The aim of this study is to discuss the biomechanical and functional fundaments of occlusion for implant-supported fixed dentures with mediate and immediate loading to provide clinical evidences for longevity of this treat ment modality based on the current literature. According to this, some prerequisites as proper bone quality, excellent primary stability, sufficient number of implants, rigid splinting, and control and mastering of biomechanical fundamentals of static and dynamic occlusion are mandatory for treatment predictability and longevity.

Influence of crown-to-implant ratio, retention system, restorative material, and occlusal loading on stress concentrations in single short implants

Purpose: The aim of this study was to assess the contributions of some prosthetic parameters such as crown-to-implant (C/I) ratio, retention system, restorative material, and occlusal loading on stress concentrations within a single posterior crown supported by a short implant. Materials and Methods: Computer-aided design software was used to create 32 finite element models of an atrophic posterior partially edentulous mandible with a single external-hexagon implant (5 mm wide × 7 mm long) in the first molar region. Finite element analysis software with a convergence analysis of 5% to mesh refinement was used to evaluate the effects of C/I ratio (1:1; 1.5:1; 2:1, or 2.5:1), prosthetic retention system (cemented or screwed), and restorative material (metal-ceramic or all ceramic). The crowns were loaded with simulated normal or traumatic occlusal forces. The maximum principal stress (σmax) for cortical and cancellous bone and von Mises stress (σvM) for the implant and abutment screw were computed and analyzed. The percent contribution of each variable to the stress concentration was calculated from the sum of squares analysis. Results: Traumatic occlusion and a high C/I ratio increased stress concentrations. The C/I ratio was responsible for 11.45% of the total stress in the cortical bone, whereas occlusal loading contributed 70.92% to the total stress in the implant. The retention system contributed 0.91% of the total stress in the cortical bone. The restorative material was responsible for only 0.09% of the total stress in the cancellous bone. Conclusion: Occlusal loading was the most important stress concentration factor in the finite element model of a single posterior crown supported by a short implant.

O tratamento da apneia obstrutiva do sono e a utilização de implantes osseointegráveis: revisão da literatura

The obstructive sleep apnea syndrome affects millions of people around the world. The mandibular repositioning devices have been indicated in cases of mild/moderate syndrome; however in edentulous patients its use is deficient since there is no retention. Therefore the objective of this study was to conduct a review on the use of this treatment method combined to osseointegrated implants. A search on the theme: Dental implant and sleep apnea syndromewas performed in the Medline/PubMed, ISI, Cochrane, Dentistry Oral Science, Clinical Trials, Controlled Trials, and Bireme-BvS, databases, and 22 articles were found. After anevaluation 2 studies were selected and the review was complemented with an analysis of randomized controlled trials in the previous seven bases using the key-words: Sleep apnea syndrome, Oral appliance and Randomized controlled trial. The search returned 37 articles, and after they were submitted to inclusion criteria 17 studies were selected. There are a small number of studies presenting the use of dental implants as a mean to assist the stabilization of the mandibular repositioning appliances; those that are available are case reports that focusing on the effectiveness of the technique. Studies examining the effect these appliances in dentate patients indicate improvement in the levels of apnea and snoring. The use of mandibular repositioning appliances in dentate patients is an effective technique in treatment of patients with obstructive sleep apnea syndrome mild/moderate. Randomized controlled trialsare required in order to enable an analysis of the use of mandibular repositioning devices with the aid of dental implants .

Osseointegration of anodized implant: effect of fibrin adhesive/TEA on primary stability

Processo FAPESP: 2012/24545-3

Planejamento em reabilitação oral: restabelecimento da relação intermaxilar por meio de prótese provisória overlay

The present article describes the treatment planning and fabrication of overlay denture to restore the jaw relationship in a partial edentulous patient with bruxism. A male patient, 51 years old, was referred to the oral rehabilitation clinic complaining about the chewing and aesthetic. The occlusal surface of the superior teeth presented severe wear. The fabrication of an interim overlay denture to restore the jaw relationship was planned. The overlay had metallic projections and covered the occlusal surface of superior teeth. After overlay insertion both function and aesthetic of the patient were recovered. It was concluded that the use of overlay improved the physiological normal position of the jaw and could provide a favorable prognosis for a definitive oral rehabilitation with implant-supported fixed denture.

Solução estética para prótese sobre implante

Próteses sobre implantes esteticamente favoráveis estão diretamente relacionadas com a condição dos tecidos moles e duros que as envolvem. A preservação dos tecidos mucogengivais ao redor de implantes dentários instalados na maxila anterior propicia um sorriso harmonioso, com uma estética bastante agradável. No entanto, em alguns casos, isso não ocorre principalmente pela grande reabsorção tecidual na região, na qual deveria ter sido realizado enxerto ósseo, antes mesmo da instalação dos implantes. Desse modo, o objetivo deste trabalho foi apresentar uma solução reabilitadora estética para essas possíveis falhas durante o planejamento com reabilitações sobre implantes, por meio de gengiva artificial cerâmica.

Prótese total fixa na maxila: soluções protéticas

The modalities of treatment with prostheses over implants for total edentulous patients can be divided in fixed and removable prostheses (overdentures). The fixed prostheses modality has proven to offer better results as to the functional aspects and, results in higher longevity. Overdentures are considered as a modality of rehabilitation utilized to compensate the need for better retention, aside from augmenting chewing efficiency. Its use is justified by its facilitated hygiene, reduced surgical and prosthetic costs, reestablishment of labial support and elimination of the possibility of air escape. However, this option presents psychosocial downside, since the fact that it is considered a removable rehabilitation modality does not please the majority of patients. Although many patients prefer a fixed implant-supported prosthesis to a removable overdenture, frequently it is necessary to utilize an implant retained overdenture as an alternative to the treatment, due to anatomical, physiological, aesthetic, hygienic, and financial limitations regarding the patient. The objective of this study was to discuss a clinical case of a partially edentulous patient treated in the Implantodontic Surgery Post-Graduation Course from the Kenedy Dentistry Institute Mozarteum/Famosp Unit – Goiânia-Brazil), and submitted to osseointegrated implants surgical fixation techniques. A modality of differential diagnosis was established after osseointegration period, it aimed at facilitating the choice of a rehabilitation model that could favor the patient’s and professional`s expectations. Therefore the appreciated aspects were function, comfort, aesthetics, and especially the patient satisfaction.

Implantes Platform Switching: longevidade e preservação óssea: revisão crítica da literatura

The concept of switching platform is the use of an implant by platform wider than the abutment. Recently, researches have shown that this type of dental implant design tends to offer a higher preservation of crestal bone when compared to the traditional pattern of bone loss. The present study aims to perform a critical review on the switching platform concept establishing possible advantages of the technique. A search was performed on Medline/Pubmed about the topic “dental implant” and “platform switching”, and after applying inclusion criteria 40 studies were selected. The literature on longevity present prospective studies that show less bone loss, studies in biomechanics exhibit better or similar stress distribution around the bone crest, however, is not yet defined the role of the biological width. Thus, studies of longevity, and randomized prospective studies are of a great relevance to be performed in order to confirm the benefits of this technique and to establish a protocol indication. It is possible, based on this literature review, to conclude that longitudinal and randomized studies show that the platform switching implants have longevity and less bone loss. Biomechanically, the technique is possible.

Dental implant fractures: aetiology, treatment and case report

Purpose: This study aimed to investigate the etiology, clinical manifestations, and treatment options of dental implants fractures through a literature review and to relate a clinical report. Methods: A literature review was performed using the Medline database and this paper describes a case demonstrating the management of implant fracture. Twenty two articles were selected in the present literature review. Results: Nowadays the use of dental implants to rehabilitate completely and partially edentulous patients became the best treatment option; however, this treatment is suitable to failure. The fracture of implant body is a possible complication. The fracture of implant body is a late complication and is related to the failure in implant design or material, non-passive fitting of the prosthetic crown and overloading. Clinically, prosthesis instability and spontaneous bleeding are observed. Three options of treatment have been indicated: complete removal of implant fragment, maintenance of implant fragment, and surface preparation of the fragment with insertion of a new abutment. Conclusion: The literature indicates the complete removal of the fragment as the best treatment option.

Esthetics in implant-supported prostheses: a literature review

Esthetics is important for success of implant-supported prostheses. This study aimed to review esthetics concepts for implant treatment. Research in the PubMed database included studies published from 1995 to 2010 with the keywords implant esthetics, implant-supported prostheses, and esthetics. Forty-five studies were evaluated regarding the presurgical planning, surgical phase, and temporary and final restoration phases. It was concluded that esthetics in implant-supported prostheses results from a multidisciplinary approach from planning until insertion of the final restoration.

Implantes osseointegrados: evolução e sucesso

Introduction: The oral rehabilitation with dental implants is a very viable treatment modality for patients. Therefore the discovery of osseointegration, dentistry has reached the trigger with respect to treatment with a high predictability of success. For this various principles, since the surgical protocols, the choice of material and even the technique for the manufacture of implant-supported prosthesis influence a good prognosis for treatment. Objective: Therefore, it is proposed this study a literature review of the fundamentals of osseointegration, explaining the historical and technical parameters of implantology, focusing in what the literature currently is studying with more intensity, the acceleration of osseointegration. Conclusion:well conducted procedures promotes the best aimed success in implantology. Rough surfaces shows great are for implant-bone contact and better mechanical results. The bone quality is fundamental in results foresigh.

A importância da mucosa queratinizada na implantodontia

The purpose of current implantology is to ensure that implants maintain its state of full health, proper function and aesthetics. The aim of this paper is to discuss, through a literature review, the importance of keratinized mucosa in relation to cleaning, gingival maintenance, aesthetics involving dentistry implant and evaluating some options to provide a keratinized mucosa when it is insufficient. For the studies identification, it is included or considered in this review, Pubmed database with the following keywords: implant and mouth mucosa and, according to the criteria for inclusion and exclusion, 27 articles were selected. According to the reviewed articles, it was found that the keratinized tissue does not influence the survival of the implant, but it facilitates the cleaning, decreases the irritation of the peri-implant tissues and promotes aesthetics in anterior regions.

Influência do formato do rebordo alveolar sagital em reabilitações com associação de prótese parcial removível de extremidade livre e implante ósseo integrado

The association of mandibular distal extension removable partial dentures with an osteointegrated implant is a treatment option at hasn't been fully explored by modern rehabilitation dentistry yet. The objective of this study is to evaluate, by means of the bidimensional method of finite elements, the distribution of tension on the structures supporting the distal extension removable partial denture (DERPD), associated to a 10.0 x 3.75 mm osteointegrated implant with an ERA retention system, in alveolar ridges of different shapes. Eight models were created, representing, from a sagittal perspective: Model A (MA) – a half arch with a horizontal ridge without posterior support, with the presence of the lower left canine, and a conventional DERPD, with metallic support in the incisal aspect of this canine, as replacement for the first and second pre-molars and the first and second molars of the lower left half arch; Model B (MB) – similar to MA, but different because of the presence of a 3.75 x 10.00 mm implant with an associated ERA retention system in the posterior region of the DERPD base; Model C (MC) - similar to MA, however with a distally ascending ridge format; Model D (MD) – similar to MC, but different because there is an implant associated to a retention system; Model E (ME) - similar to MA, however with a distally descending ridge format; Model F (MF) – similar to ME, but ditfferent in the sense that there is an implant with an associated ERA retention system; Model G (MG) – similar to MA, however with a distally descending-ascending ridge format; Model H (MH) – similar to MG, but different in the sense that there is an implant with an associated ERA retention system. The finite element program ANSYS 9.0 was used to load the models with vertical forces of 50 N, on each cuspid tip. The format of distal descending edge (ME and MF) was that presented worse results, so in the models with conventional RPD as in the models with RPD associated to the implant and ERA system of retention, for the structures gingival mucosa and tooth support. 1) the distally descending ridge presented the most significant stress in the model with the conventional RPD (ME) or with a prosthesis associated to an implant (MF) and 2) the horizontal ridge (MB) provided more relief to the support structures, such as the tooth and the spongy bone, when there was an implant associated to an ERA retention system. The incorporation of the implants with the ERA system retention, in the posterior area of the toothless edge, it promotes larger stability and retention to PPREL, improving the patient's masticatory acting and, consequently, its comfort and function.

The influence of the alveolar ridge shape on the stress distribution in a free-end saddle removable partial denture supported by implant

The alveolar ridge shape plays an important role in predicting the demand on the support tooth and alveolar bone in the removable partial denture (RPD) treatment. However, these data are unclear when the RPD is associated with implants. This study evaluated the influence of the alveolar ridge shape on the stress distribution of a free-end saddle RPD partially supported by implant using 2-dimensioanl finite element analysis (FEA). Four mathematical models (M) of a mandibular hemiarch simulating various alveolar ridge shapes (1-distal desceding, 2- concave, 3-horizontal and 4-distal ascending) were built. Tooth 33 was placed as the abutment. Two RPDs, one supported by tooth and fibromucosa (MB) and other one supported by tooth and implant (MC) were simulated. MA was the control (no RPD). The load (50N) were applied simultaneously on each cusp. Appropriate boundary conditions were assigned on the border of alveolar bone. Ansys 10.0 software was used to calculate the stress fields and the von Mises equivalent stress criteria (σvM) was applied to analyze the results. The distal ascending shape showed the highest σvM for cortical and medullar bone. The alveolar ridge shape had little effect on changing the σvM based on the same prosthesis, mainly around the abutment tooth.

Sexual haressement in dentistry: prevalence in dental school

OBJECTIVE: Sexual harassment is unlawful in all work and educational environments in most nations of the world. The goals of this study were to describe the sexual harassment prevalence and to evaluate the experiences and attitudes of undergraduate students in one dental school in Brazil. MATERIAL AND METHODS: An 18-item questionnaire was administered to 254 dental students with a completion rate of 82% (208). Students were requested to respond to questions about their background and academic level in dental school, their personal experiences with sexual harassment and their observation of someone else being sexually harassed. Bivariate statistical analyses were performed. RESULTS: Fifteen percent of the students reported being sexually harassed by a patient, by a relative of a patient or by a professor. Male students had 3 times higher probability of being sexually harassed than female student [OR=2.910 (1.113-7.611)]. Additionally, 25.4% of the students reported witnessing sexual harassment at the school environment. The majority of students did not feel professionally prepared to respond to unwanted sexual behaviors. CONCLUSION: These findings demonstrate that sexual harassment can occur in a dental school setting. There is a need for ongoing sexual harassment education programs for students and university staff. Increased knowledge of sexual harassment during graduation can better prepare dental professionals to respond to sexual harassment during their practice.