Effect of UV-photofunctionalization on oral bacterial attachment and biofilm formation to titanium implant material

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Abutment coating with diamond-like-carbon films to reduce implant-abutment bacterial leakage

Backgroud: The influence of diamond-like-carbon (DLC) films on bacterial leakage through the interface between abutments and dental implants of external hexagon (EH) and internal hexagon (IH) was evaluated. Film deposition was performed by PECVD (Plasma Enhanced Chemical Vapor Deposition). Sets of implants and abutments (N=180, n=30) were divided according to the connection design and the treatment of the abutment base: (1) no treatment (control); (2) DLC film deposition, and (3) Ag-DLC film deposition. Under sterile conditions, 1 µL of Enterococcus faecalis was inoculated inside the implants, and abutments were tightened. The sets were tested for immediate external contamination, suspended in test tubes containing sterile culture broth, and followed-up for five days. Turbidity of the broth indicated bacterial leakage. At the end of the period, the abutments were removed and the internal content of the implants was collected with paper points and plated in Petri dishes. They were incubated for 24 h for bacterial viability assessment and colony-forming unit (CFU) counting. Bacterial leakage was analyzed by Chi-square and Fisher exact tests (α=5%). The percentage of bacterial leakage was 16.09% for EH implants and 80.71% for IH implants (P<0.0001). The bacterial load was higher inside these implants (P=0.000). The type of implant significantly influenced the results (P=0.000), whereas the films did not (P=0.487). We concluded that: (1) IH implants showed a higher frequency of bacterial leakage and (2) the DLC and Ag-DLC films did not significantly reduce the frequency of bacterial leakage and bacteria load inside the implants.

The Fresh Frozen Bone Allograft (FFBA) to reconstruc the atrophic maxilla: evaluation of the clinical and histological viability at six and nine months in the maxillary sinus

This work aimed to analyze clinically and histologically the allogen bone graft behavior at 6 and 9 months. A leukoderm, female, 55 years old patient sought dental care for oral rehabilitation with dental implants and implant supported fixed prosthesis in the maxilla. Bilateral sinus lifting procedure were performed in a same patient, the analysis were made after 6 and 9 months, respectively. At 6 months, there was lack of a better bone remodeling in the region, associated to the presence of fibrous connective tissue within the collected tissue, showing us that this is not the best stage of tissue maturation to place dental implants. The 9 months period showed an improvement, with a more organized bone tissue surrounding particles of homogenous bone, what possibly had increased implant stability at the time of surgery. There is no doubt about the increase of clinical applications of FFBA, but there are no studies available regarding the standardization of time to load implants inserted in allografts. So papers with long-term monitoring are necessary to eliminate questions that still remain to be answered.

Reconstrução imediata de fenestração peri-implantar com enxerto autógeno em bloco de ramo mandibular

Alveolar wall fenestrations are common during implant placement. The aim of this paper is to report a case where a peri-implant bone fenestration was reconstructed immediately after implant placement by an autogenous mandibular bone block. A male patient was referred to the Department of Surgical and Integrated Clinics to substitute his Kennedy´s Class IV removable partial denture for an implantsupported fixed prosthesis. A peri-implant bone fenestration at the buccal wall was seen at the region of 12, being reconstructed by a mandibular bone block secured by a bicortical screw. Six months later the surgical procedures, an implant-supported complete fixed partial prosthesis was developed. The autogenous bone block harvested from the mandibular ramus was a safe alternative to reconstruct the peri-implant bone defect such as fenestration types.

Enxerto de tecido conjuntivo para correção da margem peri-implantar

Soft tissue recessions frequently cause esthetic disharmony and dissatisfaction. The results of coverage in peri-implant sites, in comparison with soft tissue coverage around a tooth, is less predictable. This clinical report describes the correction of an esthetic problem with a single-tooth implant-supported using a subepithelial connective tissue graft (SCTG) combined with the re-establishment of a new limit of gingival margin, and emergence crown profile. After anamnese and clinical exam it was observed an implant in the region of tooth 22 in vestibular position to alveolar ridge with a recession of 5 mm in its vestibular face. In the first cirurgical procedure the crown and the abutment were removed and a SCTG associated with a coronally positioned flap was performed in order to re-establish the limit of gingival margin. After 90 days, it was observed that the tissue in the implant site showed no adequate volume or thickness. Because of that, another SCTG was performed. The reopening procedure to install the healing cap was performed after 4 weeks. Then the prosthesis was installed. At 180 and 360 days postoperative, the implant adjacent tissue presented regular contour, color compatible with health and absence of bleeding. The patient was satisfied with the esthetic result. According to the clinical results and favorable esthetics it was possible to conclude that the use of ETC to correct an esthetic deficiency may be a feasible approach to establish new and stable peri-implant soft tissue contours.

Histologic and histometric evaluation of calvarial autogenous bone graft in reconstruction of atrophyc maxilla for dental implants

The calvarial bone is highlighted as a good donor area for large reconstructions of atrophic jaw for subsequent rehabilitation with implant-supported prosthesis. The aim of this study was to observe and measure through histological and histometric evaluation, the cellular events that occur at the interface of union from onlay parietal bone graft on the maxilla of 10 patients, after a period of 6 months of incorporation. The biopsies were performed at the time of installation of osseointegrated implants. The bone contact area represented 78.75% and connective contact 21.25%. The region of connective union between the bone graft to the maxillae presented new bone formation (41.26%), marrow bone (36.06%), osteoid tissue (15.86%) and connective tissue (6.80%). All samples had good graft incorporation to the receptor bed with osteogenic activity and absence of inflammatory cells.

Impacto do uso de fita adesiva na qualidade de vida de pacientes institucionalizados e usuários de próteses totais convencionais

Objective: Evaluate the impact of the use of strip adhesive over the quality of life of institutionalized patients and wearers of complete dentures. Material and method: Twenty-nine institutionalized patients wearers of complete denture were selected to this study and after a clinical exam, a questionnaire (adjusted and based upon the index of Oral Health Impact Profile and Oral Health-Related Quality of Life, OHIP and OHQOL) was applied to evaluate issues related to epidemiological conditions (gender and age), quality of life (pain, discomfort, functional limitations, phonetic, social, psychological and esthetic), taste and notion of implant treatment. Following this part, the patients received instruction to use the strips adhesives (Corega Fita Adesiva, Glaxo-Smith-Kline, Rio de Janeiro, Brazil), considering three in maxillary prosthesis and two in the lower prosthesis during a period of 30 days. After this period, all the patients were recall and the questionnaire was reapplied; add some adhesive performance questions, to compare the results before and after the adhesive use in terms of percentage. Result: After the adhesive strips use there were improvement of the functional, social and physcological limitation aspects, but without percentual increasement of phonetic and esthetics aspects. The results showed 65.5% of the answers stating adhesive maintenance between 6-12 hours, easy removal (68.9%), and without change the taste (89.6%). The notion for implant treatment was decreased changing from 75.8 to 37.9% after the adhesive use. Conclusion: The results enhanced a positive impact over quality of life of the respondents after the strip adhesive use, showing decrease of pain and discomfort, mainly of inferior dental prosthesis.

A importância da geometria dos implantes para o planejamento em reabilitação oral: revisão de literatura

The design of implant structure is still a questioning to the professionals, while their variations can to influence of stress distribution favorably to bone. Therefore, the aim of study was to review addressing the topic of osseointegrated implants design establishing answers for the patient oral rehabilitation, according variations existing on the market. It was conducted a detailed search strategy by the PubMed/ Medline and Bireme, it was used as descriptors: “dental implants cylinder”; “dental implants thread”; “dental implants geometry”, until May 2014. From 798 articles, after review were selected 18 articles and 1 specific area book. The results were divided to compare design of implant and threads for further discussion and conclusions. Thus, conclude that the threads implants are best used because of its advantages with respect to the stress distribution and stability primary. The variations of the differents types of threads, have influence for stress distribution.

Higienização em prótese sobre implante

With the advances of osseointegration principles, the use of implant-supported prosthesis has become a routine treatment option. The success of an implant is initially associated to the surgical technique, primary stability and absence of bacterial contamination on the implant site. Subsequently, the absence of mechanical trauma (overload) and peri-implantitis are sine qua non conditions to the longitudinal success of implant treatment. Therefore, the strict maintenance of oral hygiene is highly important to avoid biofilm accumulation around the implant and consequently to provide last-long implant-supported dentures. The clinician has the responsibility to supply a favorable prognosis to the patient so that the rehabilitation succeed. For this reason, during prosthesis fabrication the clinician should observe the design and emergency profile of the prosthesis, the peri-implant sulcus depth as well as the presence of motor or psychological impairment by the patient. Subjects with missing teeth and that will be submitted to the implant treatment should be motivated and adequate instructed regarding oral hygiene and its importance since the best option to obtain treatment longevity and consequently patient’s satisfaction is the prevention. Therefore, this study aimed to perform a literature review about the hygiene of implant-supported prosthesis.

Reabilitação protética com associação entre prótese parcial removível e implante dentário: relato de caso

Removable partial denture improve functional and aesthetic failures caused by partial loss of teeth, however specific characteristics of each patients can determine the success of treatment, especially with regard to the support of the prosthesis, which may depend on teeth, the combination of teehe and mucosa and currently associated with the dental implants. The aim of this study is report a case in which there was the need of the association, to enable better aesthetics and self-esteem to the patients. After implant placement and fabrication of prosthetic patient reported satisfaction with the rehabilitation treatment, improving their quality of life.

Influence of morphological variables in photoelastic models with implants submitted to axial loading

Purpose: This study used 12 photoelastics models with different height and thickness to evaluate if the axial loading of 100N on implants changes the morphology of the photoelastic reflection. Methods: For the photoelastic analysis, the models were placed in a reflection polariscope for observation of the isochromatic fringes patterns. The formation of these fringes resulted from an axial load of 100N applied to the midpoint of the healing abutment attached to the implant with 10.0mm x 3.75mm (Conexão, Sistemas de Próteses, Brazil). The tension in each photoelastic model was monitored, photographed and observed using the software Phothoshop 7.0. For qualitative analysis, the area under the implant apex was measured including the green band of the second order fringe of each model using the software Image Tool. After comparison of the areas, the performance generated by each specimen was defined regarding the axial loading. Results: There were alterations in area with different height and thickness of the photoelastic models. It was observed that the group III (30mm in height) presented the smallest area. Conclusion: There was variation in the size of the areas analyzed for different height and thickness of the models and the morphology of the replica may directly influence the result in researches with photoelastic models.

A utilização de abutment de zircônia na reabilitação oral: aspectos protéticos e periodontais

Zirconia abutments are used to obtain satisfactory aesthetic results in implant fixed anterior prostheses when metal abutments promote a grayish mucosal discoloration of the peri-implant soft tissues. However, there is a lack of studies to confirm the clinical performance of the peri-implant soft tissues surrouding zirconia abutments. This study described a case report of a patient treated with implant fixed all-ceramic crown made out on zirconia abutment after 3 years of followup. A 47-year-old female patient was admitted to the dental clinic (Aracatuba Dental School) complaining about the fracture of her implant fixed single crown in the region of the left lateral incisor. The patient chose the replacement of the fractured prosthesis for an allceramic crown. After 3 years of follow-up it was observed that maintenance of the aesthetic results and the peri-implant soft tissue without any inflammation or gingival recessions. Within the limitations of a case report, it can be conclude that zirconia abutments is a effective rehabilitation treatment because it preserves the aesthetics and function through the maintenance of peri-implant tissues.

Manutenção em próteses implantossuportadas: higiene oral

The maintenance of Implant-supported Prosthesis is essential to the success of dental implants. Therefore, the aim of the study was to conduct a review the literature addressing maintenance Implant-Supported Prosthesis in order to guide planning for the longevity of oral rehabilitation. We conducted a detailed search strategy for the Pubmed / Medline Dentistry and Oral Science, used as descriptors: “Oral Hygiene“ and “Dental Implant until July, 2013. The results were grouped together in topics (Clinical Exam and Oral Hygiene) and discussed. Conclusion: A regular maintenance program for oral patient implantprosthesis is essential to the longevity of the treatment. Different methods and devices are effective for cleansing. However one orientation (in writing) must be offered to patients, since inadequate cleaning can create regions of abrasion on the surfaces of abutments and dental implants.

Influência do aumento do comprimento de implantes dentários

The use of implants of greater length may be more favorable for the predictability of dental implants. This statement is relevant, since the cause of failures in dental implants are more related to biomechanical complications. The aim of this study was to evaluate the influence of increase of the length around the entire body of the implant. Six models were created with the presence of only one hexagonal implant (Master Screw connection, Implant Systems, São Paulo, Brazil) of 3.75 mm x 7.0 mm (Model A), 3.75 mm x 8.5 mm (Model B ), 3.75 mm x 10.0 mm (Model C) 3.75 mm x 11.5 mm (Model D) 3.75 mm x 13.0 mm (Model E) 3.75 mm x 15.0 mm (Model F) using the method of photoelasticity. The results were visualized through a qualitative analysis of stresses (number and intensity photoelastic fringes). The model A showed a pattern of less favorable stress distribution, the oblique loading was the most detrimental to the related structures. Conclusion: The increased length allowed for a better distribution of stresses. The oblique loading was more detrimental when compared to axial loading.