v. 06, no. 3
Dental Press Implantology – ISSN 2237-650X
Dental Press Implantol.
v. 06, no. 3
July / August / September
Biology, combined with technology, increasingly provides options for Implantology to grow in its techniques and possibilities, offering patients proper oral rehabilitation, even if they present systemic problems such as diabetes mellitus, syndromes such as ectodermal dysplasia, anodontias and other edentulism situations.
In each issue of this journal, we have new approaches on biomaterials, maxillary sinus lifting, distraction osteogenesis and also about the best time to implant placement with or without immediate loading.
Technical possibilities are extended and a systematic reading of the articles is mandatory for constant updating not only for the clinician, but especially for those who research and teach Implantology. In the modern world there is no longer place for professionals highly specialized in one field of knowledge: Interact with other specialties and their possibilities is a requirement of how Implantology advances, crossing up with other areas.
The increasing presence of Brazilians abroad, researching and coming back to the country with new possibilities, further enriches our Dentistry. Like a strategic plan, the constant presence of Brazilians in prominent places at the best universities in the world – such as Luiz Meirelles, the interviewee of this issue - open spaces so that other fellows may transit in laboratories and clinics with different approach of world’s Implantology, enriching our specialty in the context of Brazilian Dentistry.
This interview will allow us to know a little better this notable Brazilian, take his life experience as an example and perhaps interact with him for new enriching contacts, including in the federal program “Science without borders”.
Let us take it!
Prof. Alberto Consolaro
Many Brazilians dream of studying abroad. Perhaps to build a career in another country or just to make a true contribution for Brazil in the field of science and technology. What if this contribution positively affects the improvement of a product that benefits hundreds of patients? In this case, we would be talking about a young prodigy named Luiz Augusto Meirelles who gave us this amazing interview. It was in 2007 that we had the grateful surprise to meet Luiz. We organized a group of people that went to Gothenburg, Sweden, to participate of the first Brazilian Day (Dental Press Magazine, Periodontics Implantology, v. 1, n. 3, p. 110-111, jul./aug./sep. 2007). We had many lectures given by professors from Sweden and Brazil, in a scientific exchange very beneficial to our team. On the following day, we watched the interviewee’s thesis defense. Actually we saw a young man to be truly massacred with objective questions, sometimes aggressive, from his accuser (Professor Lyndon Cooper, USA), regarding his works in surfaces of implants, especially in nanotopography. However, for our joy, he not only did very well, but also was applauded by his compatriots and by the Swedes present at the end of the works. Today we have a friend who exercises the teaching and researching at the University of Rochester, in the U.S., and that at 37 years of age is already quoted by the most renowned researchers, as one of the world’s leading authorities in the field of surfaces of osseointegrated implants. Luiz Meirelles graduated in Dentistry in 1998 at the Federal University of Rio de Janeiro and worked in different research projects in the area of osseointegration during scientific initiation. In 2001 he started the master’s degree at the Faculty of Piracicaba (Unicamp), analyzing the distribution of stress on implants through a photoelastic analysis. He concluded the program in March of 2003 and initiated the doctorate at the University of Gothenburg in the same year. His doctorate program was focused in modifications on the surface of dental implants, characterizing the nanostructures with an innovator model. He defended his PhD thesis in 2007, being one of the pioneer researchers on the evaluation of bone response related to nanotopography. Today, he works at the University of Rochester as Assistant Professor of the Eastman Institute for Oral Health and the Faculty of Bioengineering. He is the head of a laboratory of research in biomaterials and works with patients in rehab. Luiz Meirelles is married and father of twin girls.Luis Rogério Duarte
Explanations and applications
The bone reactional capability and the names of inflammatory bone diseases
Osteitis. Osteomyelitis. Periostitis. Osteonecrosis.
The bone reactions before functional demands and aggressions are different according to the local morphology, intensity and duration of the irritation and systemic state of the patient. In this work, initially it was sought to correlate these three important factors to comprehend the final result on the bone structure, especially from the imaging point of view. Then, it was presented the concepts of universally accepted names to identify inflammatory bone diseases, in order to facilitate the scientific and clinical communication between professionals.
Ask the Expert
Surgical elevation of maxillary sinus mucosa: Is it necessary to use biomaterials?
Sinus floor elevation surgery
The bone resorption that occurs after extraction of maxillary posterior teeth may result in severe vertical and/or horizontal bone loss, compromising the planning of rehab with implants in that region. Numerous grafting techniques have been described and used aiming to restore adequate bone volume for posterior implants installation. The most used technique to restore the anatomy of this region is the procedure of maxillary sinus floor augmentation. The maxillary sinus elevation surgery was initially described by Tatum,1 in 1986, being also reported by Boyne and James,2 and Wood and Moore.3 In this procedure the access to maxillary sinus is obtained through making a bone window on the lateral sinus wall, using a spherical diamond drill number 6-8, maintaining the sinus membrane integrity. The sinus membrane is then carefully lifted with the aid of specific curettes. This mobilization is performed with the bone window adhered to the membrane and displaced to the maxillary sinus roof. Created the desired space, the material chosen for grafting is then inserted.4 In 1994, Summer5 described an alternative surgical technique to increase the bone volume in the posterior maxilla on which the access to the maxillary sinus floor was performed through the alveolar bone crest using osteotomies of varied diameters aiming to surgically make an alveolus. The sinus mucosa was lifted and a grafting material was inserted, preceding the concomitant installation of a titanium implant. The referred technique has as main recommendation the necessity of gain of height on the maxillary sinus floor of at most 2 to 3mm. It is considered a less invasive alternative, especially for regions that did not need great sinus mucosa lifting.
Image and Science
Assessment of bone/implant interface through SEM
Images taken with the Scanning Electron Microscope (SEM) of the interface between bone and Nanotite™ implant (Biomet 3i®), with twenty-one days of osseointegration.
It is observed the intimate contact of bone with titanium nano-textured surface, as well as calcification of the collagen matrix and bone extensions created toward the surface of the implant.
Periodontal treatment in patients with diabetes mellitus type 1 and type 2: Case report
Diabetes mellitus. Periodontitis. Therapeutics.
Introduction: It is unquestionable the influence of diabetes mellitus (DM) on the pathogenesis of periodontal disease. Both conditions have got a bidirectional relation on the inflammatory response. Patients with diabetes mellitus and without a proper metabolic control show a worse status of the periodontal disease and also more difficult in the glicemic control of DM. Types 1 and 2 of DM have their particularities and clinical differences related to the metabolic control or to the periodontal therapy.
Objective: This paper reports two cases of patients with diabetes mellitus and periodontal disease, being one of DM type 1 and the other of DM type 2.
Conclusion: The post-operatory result showed resolution of the periodontal inflammation in both cases. After therapy, there were no periodontal pockets nor suppuration or bleeding on probing. However, the clinical management of both forms of DM was individualized. The use of systemic antibiotics associated to periodontal therapy was necessary only for the patient with type 1 DM.
Assessment of life quality of a patient with ectodermal dysplasia rehabilitated with osseointegrated implants: Five years clinical and radiographic follow-up
Ectodermal dysplasia. Zygomatic fixtures. Quality of life.
Ectodermal dysplasia is a genetic disorder associated with dental anomalies that severely affect function, aesthetics and quality of life. Patients with ectodermal dysplasia often have complete or partial anodontia, which affects normal jaw development. Dental implants have increasingly been used for the rehabilitation of these patients because their disease severity reduces treatment options. This report describes the pre- and postoperative quality of life of a 55-year old woman with ectodermal dysplasia that presented with hypodontia and severe atrophy of the jaws. She was treated with dental implants for immediate functional loading using the Novum® protocol for the mandible and the All-on-4® hybrid technique in the maxilla, together with zygomatic implants and 3 conventional implants. The patient was followed up for 5 years.
Treatment of vertical alveolar defects by means of osteogenic distraction technique
Distraction. Implant Dentistry.
Introduction: Alveolar reconstruction of vertical bone defects remains a daunting challenge in implant dentistry. Among the various techniques used to correct such defects is distraction osteogenesis (DO), which has been described as a technique used to gain bone and soft tissues, especially in surgeries for reconstruction of mandibular and maxillary alveolar ridges to allow the placement of dental implants in a favorable position and with greater success predictability when subjected to functional loads.
Objective: The purpose of this study was to evaluate the effectiveness of DO in two patients treated with the technique of alveolar distraction osteogenesis.
Case report: The clinical cases were evaluated for bone gain through clinical and radiographic examination, pre- and post-distraction.
Results: At the end of treatment, both cases had gained sufficient bone as to enable subsequent rehabilitation with implants. Conclusions: The success rate reported in the literature and in the cases presented here prove the efficiency of the technique and its clinical feasibility.
Characterization of implants surface of the five largest companies in the Brazilian market, on micrometric level. Part III: SIN implants
Dental implant. Brazilian implants. SIN implants. Implant surface. Roughness.
Introduction: The quality of the bone-implant interface is directly influenced by implant surface roughness and a roughness average, with the Sa between 1 to 2 μm, has demonstrated better clinical and laboratory results. In Brazil, more than two million implants per year are installed, where 79% are manufactured by domestic companies. However, very little is known or published about the characterization of surfaces of these implants, on the micrometer level. The aims of this study are to evaluate and characterize numerically the surface of the implants of SIN (Sistema de Implante Nacional) company, one of the five largest companies in the Brazilian market.
Methods: Were evaluated a total of 6 implants, purchased directly on the market, of two different designs (Tryon-HE and Strong-SW) and different batches, using light interferometry. Were performed 9 measurements randomly chosen for each unit, 3 on the tops, 3 on the valleys and 3 on the flanks of the threads. The same pattern was followed for evaluation by scanning electron microscope.
Results: The analyzed implants from this company showed Sa values of 0.84μm for Tryon-HE and 1.01 mm for Strong SW. Comparing the batches, only the SW design showed statistically significant differences between them.
Conclusions: The roughness values found herein categorize the surfaces of Tryon-HE as minimally rough, and Strong-SW implants as moderately rough.
Clinical surgical analysis of implant installed immediately after tooth extraction
Oral surgery. Dental implants. Tooth extraction.
Introduction: In the beginning of Implantology, the conventional protocol for osseointegration suggested waiting until twelve months for the process of alveolar bone’s repair before the placement of an implant. However, osseointegrated implants can be installed after tooth’s extraction at various moments. The choice of this depends on bone, functional and esthetic aspects. The insertion of an implant in the tooth socket immediately after tooth’s extraction, called immediate implant, shows a technique of oral rehabilitation quite viable and science reports high rates of success, especially in the anterior region of maxillary, where there is need to obtain satisfactory esthetic results. The main indication of this is the replacement of teeth that have no possibility of treatment. This technique is very advantageous because it takes advantage of the cellular repair period, reducing surgical time, providing immediate installation of the prosthesis, function or just esthetic, which brings great satisfaction to the patient. To reach success, the practitioner must be aware of some limiting factors that may indicate against the use of the technique. Objective: The purpose of this article is to show the advantages and disadvantages of this technique and its indications and contraindications through a literature review.
Retention influence of crowns cemented on implants with and without screw access
Cement. Retention. Implant-supported dentures. Reversibility.
Introduction: In Implantology, the retention mechanism of the restoration to the intermediate can be cemented or screwed. The cemented one present difficult reversibility, however, the use of an access hole to the screw would allow such reversibility, combining the low cost of the components to the reversibility of the screwed prosthesis.
Objective: The aim of this study is to evaluate the shear bond strength of prostheses on cemented implants, having or not access to the intermediate screw.
Methods: Sixteen specimens were prepared (similar to regular implants, "Tiprep" intermediates (Bionnovation, São Paulo / SP) and 16 metal crowns, of which 8 were for conventional crowns control (G1) and another 8 crowns were made with an access hole to the screw, trespassing the metal, being the experimental group (G2). The crowns were cemented with RelyX U100 (3M ESPE) and the specimens from the G2 had the opening of the channel restored with light cured composite resin Filtek Supreme XT (3M ESPE). Specimens were subjected to tensile test in a universal testing machine 24 hours after cementation.
Results: G1 showed average of 191.075 N; G2 showed 161.280 N. Applied the nonparametric Kolmogorov-Smirnov test, the dependent variable followed normal distribution (p = 0.923) and, with the Student t-test, there was no difference statistically significant (p = 0.353) between groups. It was considered the level of significance of 5%, p = 0.05.
Conclusions: Based on the analysis, it can be stated that the access hole to the screw does not compromise or decrease the retention of crowns.
Accidental implant displacement into maxillary sinus
Dental Implants. Oral rehabilitation. Maxillary sinus.
Introduction: The oral rehabilitation practice using dental implants have developed over the past thirty years. Like any technique, implant dentistry is subject to complications that often arise from professional inexperience, technical factors related to implant placement, the need for additional procedures and patient-related factors. Despite the large number of implants placed today, migration of an implant into the maxillary sinus is a rare complication. There are several techniques to correct it and it is up to the professional to choose the one that best suits the patient. Objective: This paper aims to report a case of accidental displacement of an implant into the maxillary sinus. Conclusions: Proper planning is the best tool to avoid such complications. It would be wise on the part of the dentist to constantly seek to improve their professional skills and knowledge in order to attain complete mastery of the theoretical and practical forms of prevention, as well as specific conducts and treatments.
Morfologic osteoconduction evaluation of Gen-Phos and Gen-Mix in rat calvaria
Biocompatible materials. Bone regeneration. Bone transplant.
Introduction: the use of bone replacements in Dentistry has increased as a result of satisfactory and predictable clinical results, lower postoperative morbidity and affordable prices. The most common material used is still the inorganic bovine bone with osteoconductive properties. In the 1980’s began the search for a synthetic material with osteoconductive results equal or superior to inorganic bovine bone. Objective: To compare histological and histometric property of osteoconductive bone compound (GenMix, Baumer) with phosphate beta-tricalcium (GenPhos, Baumer) implanted in critical size defects in rat calvaria. Results: It was observed 32.5% of new bone formation in the group of compound bone and 45.9% in the phosphate beta-tricalcium group. Conclusions: Along the time of microscopic observation of this work, one can state that the materials studied are not absorbable and that phosphate beta-tricalcium is more osteoconductive compared to the compound bone..
Dental agenesis treated with SLActive implant: Case report
Implant surface. Osseointegration. SLA modified surface.
Dental agenesis is a genetic abnormality characterized by total absence of one or more teeth. It affects about 6% of the population, affects preferably the second mandibular premolar and represents a challenge for rehabilitation because it leads to functional and esthetic problems. Currently, dental implants play a prominent role in rehabilitation, and the SLActive® implants stand out because they accelerate osseointegration, shorten it to 21 days, and ensure better quality of new bone around the implant. With high rates of success even when immediate or early loading is used, these implants have revolutionized modern Implantology. This report describes a case of dental agenesis of the second mandibular premolar treated using a SLActive® implant and a final prosthetic crown installed on the fifth postoperative week.