Critical-size defects reconstruction with four different bone grafts associated with e-PTFE membrane: A histomorphometric experimental in vivo study.

OBJECTIVES: The goal of this study was to assess the newly formed bone and the remnant biomaterial by comparing four different bone grafts used to treat critical-size defects, associated or not with the non-resorbable membrane. MATERIALS AND METHODS: Two calvaria critical-size bone defects were created in 50 male Wistar rats. They were divided into blood (G1), autogenous (G2), bioglass (G3), hydroxyapatite (G4), and xenograft (G5) groups, associated or not with e-PTFE. The experimental periods were 15 and 45 days. Sections were prepared for histomorphometric assessment. All data were analyzed by the mixed-effects model with multiple comparisons (significance level, p < .05). RESULTS: A similar level of new bone was observed for all groups, associated with a high level of vascularization. G1 and G2 ensured sovereignty over the greater quantity of new bone. A non-significant result was reported comparing groups with and without membranes. No significant result was found between the experimental synthetic biomaterials (G3 and G4). G5L achieved 22.0% of new bone after 45 days (p > .05). All groups had a stable volume of biomaterial kept in the short term (p > .05). G2 was the best material for new bone formation and final volume of biomaterial, followed by G4 < G5 < G3. Thus, it is possible that G4 had a better degradation profile among the experimental groups. CONCLUSIONS: The best results were found in the autogenous group, with higher resorption and integration; non-significative new bone was found among the experimental groups; and the regeneration of critical bone defects using an e-PTFE barrier did not present significant results on new bone formation.

Digitally Guided Lateral Sinus Floor Elevation With Simultaneous Implant Placement: 3 Case Reports With Technical Considerations.

A sinus floor elevation via lateral window (LSFE) is one of the most widely used bone augmentation procedures for implant therapy in the posterior area of the maxilla. Locating and preparing a correct opening window on the lateral sinus wall is a key step of this procedure. Conventionally, the surgeon designs and locates the window after the flap is reflected based on the information obtained from cone-beam computed tomography (CBCT) images or other diagnostic aids. Nevertheless, in spite of the advancements in CBCT imaging, clinicians may still experience hardships in situating and procuring meticulous access to the maxillary sinus by using CBCT alone. Therefore, in cases requiring an LSFE simultaneous to implant placement, a maxillary sinus surgical guide has been tested and reported to be the amiable method to be utilized as a conjunct to prevent unpredictable consequences according to its application in implying both the direction for the implant and the location of the lateral window. This article presents 3 clinical cases with a fully digital approach to guide the opening of the lateral wall of the maxillary sinus as well as the simultaneous placement of a single implant in an ideal 3D position. Based on the CBCT images and intraoral scan, a surgical guide was fabricated based on 3D software. During surgery, this teeth-supported template can be placed intraorally, guiding sinus window opening preparation. This technique makes the sinus window opening procedure simple and predictable, reduces surgical time and the risk of complications, and allows the placement of the implant in the ideal 3D position.

Digitally-Guided Lateral Sinus Floor Elevation with Simultaneous Implant Placement: Three Case Reports with Technical Considerations.

INTRODUCTION: A sinus floor elevation via lateral window (LSFE) is one of the most widely used bone augmentation procedures for implant therapy in the posterior area of the maxilla.  Locating and preparing a correct opening window on the lateral sinus wall is a key step of this procedure. Conventionally, the surgeon design and locate the window after the flap is reflected based upon the information obtained from cone-beam computed tomography (CBCT) images or other diagnostic aids. Nevertheless, in spite of the advancements in CBCT imaging, clinicians may still experience hardship in situating and procuring meticulous access to the maxillary sinus by using CBCT alone. Therefore, in cases requiring a LSFE simultaneous to implant placement, a maxillary sinus surgical guide (MSSG) has been tested and reported to be the amiable method to be utilized as a conjunct, to prevent unpredictable consequences according to its application in implying both the direction for the implant and the location of the lateral window. CASE SERIES: This article presents 3 clinical cases with a fully digital approach to guide the opening of the lateral wall of the maxillary sinus, as well as the simultaneous placement of a single implant in an ideal 3D position. Based on the CBCT images and intraoral scan, a surgical guide was fabricated base on 3D software. During the surgery, this teeth-supported template can be placed intraorally, guiding sinus window opening preparation. CONCLUSION: This technique makes the sinus window opening procedure simple and predictable, reduces surgical time as well as the risk of complications, and allows the placement of the implant in the ideal 3D position.

Bacterial Leakage Evaluation Through DNA-DNA Checkerboard Hybridization Technique in Morse Taper Implant-Abutment Connections: An In Vitro Study.

Purpose: The objective of this in vitro study was to evaluate the activity of local gel containing metronidazole (MN) in the leakage area, which was analyzed by the DNA-DNA checkerboard hybridization method. Materials and Methods: Thirty-six sets of Morse taper/mini-pillar implants were used in this study. These implants were equally divided into the following three groups: MN gel (test group), no MN gel (negative test group), and no gel (control). The gel was prepared with metronidazole (15%). Unstimulated saliva samples were collected, transferred to a Falcon tube, and stored at 37°C. The sets were partially immersed in microtubes containing 300 µL of saliva and were incubated at 37°C ± 1°C for 7 days. Microbial infiltration was evaluated (37 bacterial species and 5 species of Candida). The results were analyzed with Wald-Type, ANOVA, and multiple comparisons analysis between groups. Results: After comparing the quantity of microorganisms, both gel-treated groups (no MN gel and MN gel) had more significant microorganism presence than the control group (P < .001), and no significant result was found between the no MN gel and MN gel groups (P > .05). Regarding the bacteria found, the most common were Aggregatibacter actinomycetemcomitans, Prevotella melaninogenica, Bacteroides fragilis, and Candida tropicalis. Conclusion: Within the limitations of this study, it was concluded that the gel containing metronidazole used in this study was not effective in preventing the infiltration of microorganisms through the Morse taper implant-abutment interface.

Digital planning for two-implant-supported overdenture and bone reduction guide using cone-beam computed tomography: Simple features for predictable outcomes.

The two-implant-supported mandibular overdenture is considered a reliable treatment option to restore masticatory function. Digital planning has been shown to improve the precision and accuracy of the surgical procedure. The outcomes are indeed pertinent to the ideal three-dimentional positioning of the implant placement. Recently, the uses of cone-beam computed tomography (CBCT) and intraoral scan have improved greatly the workflow of digital planning; however, the sophisticated technology caused confusion among clinicians. The purpose of this case series was to exhibit the efficacy of a bone-supported guide in applying simultaneous implant placement and bone reduction, solely based on CBCT data. The bone reduction can therefore be determined accordingly, by adding windows to the guide, allowing the clinician to decide the amount of bone reduction as well as the location for implant placement. This novel surgical guide would not only fit properly on the bone but also provide the benefits of less-invasive surgery and the opportunity to place implants parallel. The  digital workflow described not only simplifies the fabrication process but also yields predictable surgical outcomes.

A three-dimensionally printed template for locating the screw channel in a cement-retained implant-supported crown: A digital workflow.

Locating the screw channel in a cement-retained implant-supported crown is challenging. This article describes a fully digital workflow for fabricating a 3D-printed template which can accurately guide the dentist to find the screw channel. A definitive implant cast from the patient and an implant planning software program are used in the workflow. This technique provides precise guidance for finding the location and angulation of the abutment screw access hole.

Percepção estética e desconforto de pacientes brasileiros em tratamento com bráquetes vestibulares metálicos e cerâmicos, linguais e alinhadores Invisaling® / Esthetic perception and discomfort of Brazilian patients undergoing treatment with metallic and ceramic vestibular brackets, lingual brackets and Invisaling® aligners

Resumo O tratamento ortodôntico experimenta evolução contínua em seus aparelhos, principalmente por questões estéticas e de conforto. Objetivo: avaliar a satisfação e desconforto relatados por pacientes submetidos ao tratamento ortodôntico com bráquetes vestibulares metálicos e cerâmicos, bráquetes linguais e alinhadores Invisalign®. Material e métodos: Aplicação de um questionário padronizado a 126 pacientes de ambos os sexos, em tratamento ortodôntico em consultórios particulares há pelo menos 90 dias, sem outro acessório ortodôntico. Os pacientes foram divididos em 4 grupos: grupo I (n=30) bráquetes vestibulares metálicos, grupo II (n=30) bráquetes estéticos vestibulares, grupo III (n=32) alinhadores Invisalign® e grupo IV (n=34) bráquetes fixos linguais. A comparação entre os grupos foi feita pelo teste do qui-quadrado e, quando este indicou diferença estatisticamente significativa, foram realizadas comparações múltiplas pelo teste de proporções. Resultados: Os bráquetes metálicos vestibulares foram mais percebidos pelos demais e trouxeram maior desconforto estético. Os bráquetes cerâmicos foram menos percebidos pelos demais do que os bráquetes vestibulares metálicos. Os alinhadores foram menos percebidos pelos outros do que os bráquetes vestibulares, causaram menos dificuldades na fala e na escovação, menos desconforto nas bochechas e menos dificuldades na fala. Os bráquetes linguais trouxeram menos desconforto estético, revelando também maior desconforto na língua e menos desconforto na bochecha. Conclusão: Os pacientes relataram maior desconforto estético com bráquetes vestibulares metálicos. Aparelhos linguais e alinhadores foram menos percebidos pelos demais e trouxeram menos desconforto estético aos pacientes. Todos os pacientes tratados com alinhadores o usariam novamente caso precisassem de um novo tratamento.(AU)

Abstract Orthodontic treatment experiences continuous evolution in its appliances, especially due to esthetic and comfort reasons. Objective: The aim of this study was to evaluate the satisfaction and discomfort reported by patients undergoing orthodontic treatment with metallic and ceramic vestibular brackets, lingual brackets and Invisalign® aligners. Material and methods: Application of a standardized questionnaire to 126 patients of both genders, undergoing orthodontic treatment in private orthodontic offices for at least 90 days, with no other orthodontic accessory. Patients were divided into 4 groups: group I (n=30) vestibular metallic brackets, group II (n=30) vestibular esthetic brackets, group III (n=32) Invisalign® aligners and group IV (n=34) lingual fixed brackets. Comparison between the appliances were made by the chi-square test, and when this indicated a statistically significant difference multiple comparisons were performed by the test of proportions. Results: Vestibular metallic brackets were more perceived by others and brought greater esthetic discomfort. Ceramic brackets were less perceived by others than metallic vestibular brackets. Aligners were less perceived by others than vestibular brackets, caused fewer speech and brushing difficulties, less discomfort on the cheeks and less speech difficulties. Lingual brackets brought less esthetic discomfort, revealing also more tongue discomfort and less cheek discomfort. Conclusion: Patients reported more aesthetic discomfort with metallic vestibular brackets. Lingual appliances and aligners were less perceived by others and brought less esthetic discomfort to patients. All aligners patients would use these appliances again if they needed new treatment.(AU)

Iodoform and silver-coated abutments preventing bacterial leakage through the implant-abutment interfaces: In vitro analysis using molecular-based method.

OBJECTIVES: The aim of this in vitro study was to evaluate the effectiveness of an iodoform paste and silver-coated abutments in preventing the microbial colonization and leakage through the implant-abutment interface of morse taper and internal hexagon implants. MATERIAL AND METHODS: Seventy-two implants with morse taper (n = 36) or internal hexagon connections (n = 36) were investigated. Implants were treated with iodoform paste (n = 12), silver-coated abutments (n = 12), or control (n = 12). After saliva incubation, Checkerboard DNA-DNA hybridization was used to identify and quantify up to 43 microbial species colonizing the inner parts of the implants. ANOVA-Type and Wald-Type analyses of variance were used to investigate the relative effects and their interaction. Friedman- Conover test adjusted by Benjamini-Hockberg FDR were performed for pairwise multiple comparisons. Significance was set as p < 0.05. RESULTS: Analyses of variance indicate a significant interaction between connections, antimicrobial treatments, and species. The frequency of contamination was reduced in the implants submitted to the antimicrobial treatments. Iodoform and silver-coated abutments significantly reduced the total microbial counts in the internal hexagon implants. The lower microbial counts were recorded for morse taper implants with silver-coated abutments. CONCLUSIONS: Iodoform paste and silver-coated abutments have influenced the microbial leakage through the implant-abutment interface, by reducing both frequency of contamination and microbial levels. Treatments were not effective in reducing the counts of the target species.

Microleakage into and from two-stage implants: an in vitro comparative study.

PURPOSE: Gaps between an abutment and a dental implant are unavoidable, and microleakage may occur, leading to problems such as malodor and peri-implantitis. The aim of the present in vitro study was to investigate leakage of Staphylococcus aureus through the implant/abutment interface by the method of bacterial culture, and to compare the leakage rates of two different types of implant-abutment connections. MATERIALS AND METHODS: Twenty Morse taper implants with abutments were divided into two groups: group A, which were evaluated for microleakage into the inner part of the implants, and group B, which were evaluated for microleakage from the inner part of the implants. Twenty internal-hexagon implants with abutments were also divided into two groups: group C, which were evaluated for microleakage into the inner part of the implants, and group D, which were evaluated for microleakage from the inner part of the implants. For the evaluation of leakage from the implants, the assemblies had the inner parts inoculated with S aureus, and each assembly was incubated in sterile brain heart infusion broth for 1 week. For assessment of leakage into the implants, each assembly was submerged in 4 mL S aureus culture in tubes and incubated for 2 weeks. The microleakage of the two implant connections was compared. RESULTS: Microbial leakage occurred in all groups, and there was no statistically significant difference between groups A and C or between groups B and D. CONCLUSIONS: In vitro, S aureus leakage through the implant/abutment interface occurred with both Morse taper and internal-hexagon implants.

Prótese imediata em implante unitário após enxerto ósseo em paciente fissurado: acompanhamento de um ano / Immediate prosthesis single implant after bone grafting in a patient with cleft lip and palate: one year follow-up

A reabilitação da região ântero-superior é uma das fases finais do tratamento das fissuras de lábio e palato, e os implantes têm-se tornado cada vez mais utilizados. Este trabalho apresenta um caso de instalação de implante com provisório imediato, após enxerto ósseo, em um paciente fissurado.

A importância da mucosa ceratinizada ao redor de implantes osseointegrados / The importance of the keratinized mucosa surrounding osseointegrated implants

A anatomia do tecido mole periimplantar é semelhante à do dente natural, uma vez que apresenta epitélio juncional e tecido conjuntivo. Entretanto, as fibras conjuntivas do dente (Sharpey) estão inseridas no osso e no cemento radicular, diferentemente das fibras que circundam o implante, pois essas apresentam uma disposição paralela em relação ao abutment (intermediário transmucoso). Portanto, o selamento periimplantar é estabelecido pela mucosa ceratinizada presente, por meio do tônus de suas fibras colágenas, proporcionando uma firme junção epitélio-implante. Assim, uma adequada faixa de mucosa ceratinizada é capaz de facilitar o controle de placa realizado pelo paciente; evita traumas no tecido mole (durante os procedimentos cirúrgicos e protéticos) e previne a migração apical da margem gengival, mantendo a homeostasia periimplantar e a estética. Enquanto não se tem um consenso na literatura sobre a quantidade adequada de zona de mucosa queratinizada em torno do implante, a presença desta mucosa parece trazer benefícios a prótese implantada.

The anatomy of soft tissue peri-implant is similar of the natural tooth in that there are connective-tissue attachment and juncional epithelial. However, the connective fibers of the tooth (Sharpey) are inserted in the bone and the cement of root, differently of the fibers that surround the implantation, therefore these present a parallel disposition in relation to abutment (intermediate transmucoso).Therefore, the sealing peri-implantar is established by the present keratinized mucosa by means of tonus of its collagens fibers, providing a firm junction epithelium-implant. Thus, one adjusted zone of keratinized mucosa is able to facilitate the plaque-control procedure, to prevent trauma in the soft tissue and to prevent the apical migration of the gingival edge, keeping the homeostasia periimplant and the aesthetic one. Until it isn’t consensus in literature about the quantity of adequate zone of keratinized mucosa around implants, the presence of this mucosa carries some benefits to implant prothesis.

O uso de microondas para polimerização de prótese total implanto-suportada submetida à carga imediata / Use of microwave for polymerization of implant-supported total prostheses submitted to the immediate load

O presente trabalho demonstra a utilização do forno de microondas para polimerização de prótese total implanto-suportada submetida à carga imediata, reduzindo o período entre a instalação dos implantes e da prótese, com resultados bastante satisfatórios e maior comodidade para o paciente.