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A busca por implantes dentários se tornou uma prática odontológica muito utilizada, no entanto, existem pacientes que não apresenta volume ósseo suficiente para receber o implante. A terapia a laser de baixa potência (LTBP) contém uma resposta relevante no desempenho dessas fases primárias da estabilidade da osseointegração. Dessa maneira, o estudo tem como objetivo analisar a eficiência e aplicação do LTBP em levantamento de seio maxilar dentro da implantodontia, ressaltando seus benefícios, limitações, importância e impacto para saúde bucal. Tratou-se de uma revisão narrativa de literatura, com seleção de artigos científicos encontrados nas bases de dados: PubMed, LILACS, BVS, SciELO e Google Acadêmico, sem período definido de publicação, com cruzamento dos Descritores em Ciências e Saúde (DeCS) e adotados os operadores booleanos "AND" e "OR". A quantidade ideal de altura óssea é importante para a reabilitação com implantes dentários e, em certos casos, o levantamento de seio maxilar se torna necessário expandir a altura de osso residual na maxila por meio da elevação da membrana de Schneider. Sendo assim, a literatura apresenta diversas formas para utilizar o LTBP na implantodontia, desde o início da limpeza na região que vai receber o implante até sua realização cirúrgica, a qual apresenta ótima melhoria na ação de osseointegração, amenizando desconfortos referentes ao pós-operatório e planejamento cirúrgico. Apesar de existir estudos controversos sobre a aplicação do LTBP no levantamento de seio maxilar para colocação de implantes, fica evidente que sua utilização obtém resultados efetivos no processo de cicatrização e reparação dos tecidos ósseos.

The search for dental implants has become a widely used dental practice; however, there are patients who do not have sufficient bone volume to receive the implant. Low-level laser therapy (LLLT) contains a relevant response in the performance of these primary phases of osseointegration stability. Thus, the study aims to analyze the efficiency and application of LLLT in maxillary sinus lifting within implantology, highlighting its benefits, limitations, importance, and impact on oral health. It was a narrative literature review, with the selection of scientific articles found in the databases: PubMed, LILACS, BVS, SciELO, and Google Scholar, without a defined publication period, with the crossing of the Health Sciences Descriptors (DeCS) and the adoption of the boolean operators "AND" and "OR." The ideal amount of bone height is important for rehabilitation with dental implants, and in certain cases, maxillary sinus lifting becomes necessary to expand the residual bone height in the maxilla through elevation of the Schneiderian membrane. Thus, the literature presents various ways to use LLLT in implantology, from the beginning of cleaning in the region that will receive the implant to its surgical implementation, which shows excellent improvement in osseointegration action, alleviating discomfort related to postoperative and surgical planning. Although there are controversial studies on the application of LLLT in maxillary sinus lifting for implant placement, it is evident that its use yields effective results in the healing and repair process of bone tissues.

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BACKGROUND: This split-mouth, double-masked, randomized clinical trial aimed at evaluating the impact of different macro geometries and nano topographical modifications on peri-implant bone repair in smokers. METHODS: Thirty-two patients who smoked at least ten cigarettes/day, with the need of a single maxillary or mandibular implant bilaterally, received two implants randomly assigned to DA - Dual Acid-Etched implants (n = 32); HCAN - healing chambers and activated nano surface (n = 32). Implant stability quotient (ISQ) was evaluated 07, 30, 60, 90, and 120 days after implant placement. Levels of bone and angiogenic markers were quantified in the peri-implant fluid after 07, 15, 30, 90, and 120 days of implant insertion. HCAN implants have a higher ISQ than DA implants at 60 days (p < 0.05). RESULTS: PLGF levels were lower for HCAN implants than for DA implants at 07-day period (p < 0.05). Besides, HCAN implants presented higher levels of OPG at 30 days and OPN, BMP-9, FGF-1, PLGF, and VEGF at 90 days, compared to DA implants (p < 0.05). The levels of EGF were higher for HCAN implants at 15, 90, and 120 days compared with DA implants (p < 0.05). HCAN implants also showed lower levels of TNF-α at 07 days in comparison to DA implants (p < 0.05) but had higher levels of DKK1 at 30 days, while DA implants presented higher levels of this marker at 90 days (p < 0.05). CONCLUSION: Macro geometry and nano topographical modifications positively modulated the bone and angiogenic factors, resulting in higher production of these markers during early peri-implant bone healing and having a positive effect on implant stabilization in smokers. TRIAL REGISTRATION: RBR-10gjvcyt; date of registration: 06/12/2023 (Retrospectively registered).

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AIM: Insertion of dental implants causes bone deformation and induces residual bone compression stress, which can lead to implant failure if the bone loss threshold is exceeded. The current literature about bone stress is restricted to computer simulations and implant primary stability measurements after installation. This work measures the torque and deformation during implant insertion testing. PURPOSE: The aim of this work was to analyze the influence surface treatment, thread profile, body shape and the presence of microthreads in the neck on the primary stability, bone deformation and residual stress during dental implants insertion. The insertion torque and resonance frequency analysis (RFA) are the main technique used to measure the primary stability of dental implants. MATERIAL AND METHODS: Five models of dental implants with different surface treatments (machined and acid etching), thread profiles (triangular and trapezoidal) and body shapes (cylindrical and conical) were inserted in synthetic bone blocks (polyurethane) with a density of 30 PCF (0.48 g/cm³) compatible with the D2 bone. The insertion torque was quantified by a digital torque driver. Strain gauge extensometry technique was used to measure bone deformation during implant insertion. RESULTS: The bone deformation and torque increase as the number of implants turns insertion increases. Dental implant with trapezoidal thread profile needs higher insertion torque than triangular threads. Implants with a conical shape require higher insertion torque than cylindrical ones. The bone stress induced by machined implant insertion exceeded the bone's mechanical resistance, causing cracks. Conical implants showed better performance than cylindrical ones. The implants with a trapezoidal thread and those with a conical body induce greater insertion torque. CONCLUSION: Comparing the mechanical behavior, it was found that the machined implants had the worst performance in terms of stress distribution in the synthetic bone, resulting in cracks in the specimen during insertion. Implants with trapezoidal threads and those with a conical body induce insertion torque and bone compression stresses that do not harm osseointegration. CLINICAL RELEVANCE: Excessive deformations in the peri-implant bone led to bone necrosis and implant failure. Thus, the surgeons must analyze the influence of surface treatment, thread profile, and body shape on the osseointegration process.

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The purpose of this study was to evaluate the effect of a single dose of ionizing radiation (30 Gy) on the osseointegration of implants in the rabbit tibia. Twenty rabbits received two dental Morse-tapered junction implants and one implant in each tibia. The animals were randomly divided into two groups (n=10), non-irradiated (NoIr) and irradiated (Ir), wherein the Ir group received a single dose of 30 Gy radiation 2 weeks after implant installation. Microtomographic analyses (BV/TV) and histomorphometric assessments (BIC and BABT) were performed 4 weeks after implant installation. One-way ANOVA, Tukey's test, and Student's t-test (α=0.05) were used for data analysis. The results showed that BV/TV did not differ significantly between the Ir and NoIr groups (P = 0.071). In the histomorphometric analysis, neither BIC nor BABT showed significant differences between the NoIr and Ir groups (p>0.05). In conclusion, ionizing radiation in dental implants does not appear to interfere with osseointegration when installed prior to irradiation.

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INTRODUCTION: Implant failures resulting from peri-implant infections can have substantial consequences, underscoring the urgent need for effective strategies to prevent biofilm formation on implant surfaces. However, despite advancements in antimicrobial surface technologies, significant challenges persist in translating these innovations into clinically viable solutions. AREAS COVERED: This article provides an overview of the limitations of current treatment protocols and explores the potential of antimicrobial surface treatments for controlling such infections. Furthermore, we highlight the importance of balancing antimicrobial efficacy with biocompatibility and mechanical stability, key factors for long-term implant performance. Finally, we address the main challenges in translating these technologies into clinical practice, including the unpredictability of long-term antimicrobial effects, regulatory compliance gaps, and methodological weaknesses in current research. EXPERT OPINION: The development of antimicrobial surfaces holds promise for enhancing the longevity of dental implants; however, current modifications face persistent challenges, hindering their translation into the dental implant market. Future advancements should prioritize 'smart' or stimulus-responsive surfaces that can release antimicrobials on demand. This strategy aims to efficiently combat infections while minimizing the risks of cytotoxicity and antimicrobial resistance, potentially leading to more effective and clinically translatable solutions.

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Background: This case report describes the clinical management of a traumatic palatal ulcer, a complication associated with mini-implant-assisted rapid maxillary expansion (MARPE). Case Report: A 13-year-old female patient with maxillary constriction underwent MARPE treatment using a custom acrylic expander anchored by four mini-implants. Despite proper planning and device design, the patient missed her first follow-up appointment and continued activations, resulting in tissue inflammation and embedding of the device. Upon examination, swelling and displacement of the cement were observed, necessitating device removal. The traumatic ulcer was treated with chlorhexidine gel, paracetamol, and a soft diet. Complete recovery was achieved within one month. A second expander was then designed and installed, with more frequent monitoring and improved hygiene protocols. This approach led to successful expansion without complications. This case highlights the importance of precise treatment planning, proper mini-implant selection, and regular follow-ups in MARPE therapy. It also emphasizes the need for patient compliance and effective hygiene measures to prevent complications. Conclusions: The successful management of the traumatic ulcer demonstrates that prompt action and consideration of cost-effective treatment options can lead to positive outcomes in addressing MARPE-related complications.

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OBJECTIVE: The study aimed to investigate whether 3D-printed titanium implants modified with magnesium and zinc ion surfaces can promote oral soft-tissue closure. METHOD: New Zealand Great White rabbits were selected as experimental animals, and the left and right side mandibular teeth of each animal were randomly divided into an experimental group and control group, each with 18 cases, and the bilateral first premolar teeth were extracted after general anesthesia, and implants were implanted into the magnesium/zinc ionized surface-treated and the surface-untreated groups, respectively. RESULTS: Under naked-eye observation, the combination of implant material and surrounding soft tissue in the experimental group was significantly better than that in the control group; fluorescence staining showed that the fluorescence density value of the experimental group was significantly higher than that of the control group (p < 0.05). CONCLUSIONS: 3D-printed titanium implants based on magnesium-zinc ion surface modification promote oral soft-tissue closure with significant results.

OBJETIVO: Investigar si los implantes de titanio impresos en 3D modificados con superficies de iones de magnesio y zinc pueden promover el cierre de tejidos blandos orales. MÉTODO: Se seleccionaron conejos grandes blancos de Nueva Zelanda como animales experimentales, y los dientes mandibulares izquierdo y derecho de cada animal se dividieron al azar en grupo experimental y grupo control, cada uno con 18 casos. Se extrajeron los primeros premolares bilaterales después de administrar anestesia general y se colocaron implantes en los grupos tratados con y sin modificación iónica de la superficie de magnesio/zinc. RESULTADOS: Bajo observación a simple vista, la combinación del material del implante y el tejido blando circundante en el grupo experimental fue significativamente mejor que en el grupo de control. La tinción de fluorescencia mostró que el valor de densidad de fluorescencia del grupo experimental fue significativamente mayor que el del grupo control (p < 0.05). CONCLUSIONES: Los implantes de titanio impresos en 3D basados en la modificación iónica de la superficie de magnesio/zinc promueven el cierre de los tejidos blandos orales con resultados significativos.

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The adhesion strength of a bacterial strain on a substrate influences colonization and biofilm development, so the biomolecular analysis of this interaction is a step that allows insights into the development of antifouling surfaces. As peri-implantitis is the main cause of failure of implant-supported oral rehabilitations and the dental literature presents gaps in the atomic bacteria/surface interaction, this study aimed to correlate the qualitative variation of roughness, wettability, chemical composition, and electrical potential of Ti-6Al-4V and Ti-35Nb-7Zr-5Ta (TNZT) disks obtained by machining (M) and additive manufacturing (AM) on the colonization and adhesion strength of S. aureus quantified by atomic force microscopy (AFM). The samples were evaluated for roughness, electrical potential, and S. aureus colonization and adhesion strength by specific methods in the AFM with subsequent analysis in the NanoScope software analysis, wettability by sessile drop method, and chemical composition by energy dispersive x-ray spectroscopy (EDX). Qualitative data were correlated with bacterial adhesion strength. The greater adhesion strength of S. aureus was observed in descending order for TNZT AM, TNZT M, Ti-6Al-4V AM, and Ti-6Al-4V M. This experimental in vitro study allowed us to conclude that for the evaluated groups, the strength adhesion of S. aureus showed a linear relationship with roughness, and nonlinear for wettability, electrical potential, and S. aureus colonization on the surfaces evaluated. As for the two variation factors, type of alloy and manufacturing method, those that promoted the lowest bacterial adhesion strength were Ti-6Al-4V and M, possibly attributed to the synergistic modification of the evaluated surface properties. Thus, this study suggests S. aureus preferences for rough, hydrophilic surfaces with a greater electrical potential difference.

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OBJECTIVES: To investigate the influence of combining levels of metal artifact reduction (MAR) tool with different filters and slice-thickness in the detection of mandibular canals perforated by implants on CBCT scans and to objectively assess the impact of the aforementioned combinations. MATERIALS AND METHODS: Implants were placed above (8 implants) and inside (10 implants) mandibular canals of dried-mandibles. CBCT scans were obtained with the Eagle 3D unit (85 kVp, 8 mA, 5 × 5 cm FOV, 130 µm voxel size, and off/medium/high MAR levels). Examiners evaluated the scans under each MAR level and across different conditions: no filter, Sharpen 1×, Sharpen 2×; 0 mm, 1 mm, and 2 mm slice-thickness. The gray values on axial reconstructions were assessed. Area under the receiver operating characteristic curve (AUC), sensitivity, specificity, mean and standard deviation (SD) for gray values were calculated and compared by multi-way Analysis of Variance. RESULTS: Overall, the AUC and sensitivity decreased with high-level MAR (p < 0.0001), regardless other variables tested. Enabling MAR tool decreased mean gray values (p < 0.01) and increasing MAR levels reduced the SD values on scans with Sharpen 2× (p < 0.012). CONCLUSIONS: High-level MAR impairs the visualization of mandibular canals perforated by implants. Moreover, enabling MAR tool decreases the mean gray values. CLINICAL RELEVANCE: MAR tool, filters, and slice thickness influence the image quality of CBCT scans. Therefore, it is important to evaluate the impact of these parameters on the diagnosis of mandibular canals perforated by implants.

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OBJECTIVES: To evaluate whether the application of an anaerobic adhesive (AA) to the abutment screws interferes with the implant stability quotient (ISQ) values in abutments with external hexagon (EHC) and conical connections (CC). MATERIALS AND METHODS: 20 implants 4.0 mm x 10 mm were used, with similar formats, 10 with EHC and 10 with CC, inserted by the same operator into fresh bovine ribs. The abutment was then screwed with a high precision digital torque meter, and resonance frequency was measured. The abutments were then unscrewed, a drop of Loctite 242 adhesive was applied along the entire length of the thread, the abutments were screwed again (Groups EHC-AA and CC-AA). The ISQ was registered immediately, 24 h, and 72 h after installation. Data were analyzed using descriptive statistics and comparison tests (p < 0.05). RESULTS: ISQ values measured in abutments without AA were significantly higher than those measured after applying the adhesive, for EHC and CC. The one-way repeated measures ANOVA showed that, in the intragroup analysis, there was no statistically significant difference in the ISQ, comparing the three measurement moments after applying the adhesive, irrespective of connection system (CC: F = 0.191, p = 0.827; EHC: F = 0.323, p = 727), which suggests that the adhesive curing does not affect the ISQ. CONCLUSIONS: The use of an AA on abutment screws had a significant effect on RFA measurements, for EHC and CC. The curing time of the AA did not affect the ISQ values measured in the abutments. CLINICAL RELEVANCE: The ISQ values cannot be compared in situations with and without AA.

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Medication-related osteonecrosis of the jaw (MRONJ) is a progressive condition that can cause significant bone loss and its diagnosis can be challenging. A 68-year-old man with a diagnosis of hepatocellular carcinoma, undergoing treatment with atezolizumab, bevacizumab and zoledronic acid, complained of spontaneous pain in the right lower second premolar. Oral examination revealed no dental changes and implants in the right jaw. A patient history and thorough clinical and radiographic examinations mimic endodontic disease. The implant crowns were removed, bleeding on probing, and peri-implant pockets were observed. The main hypothesis was MRONJ Stage 2, and the surgical treatment was performed. The pain ceased and signs of MRONJ were not observed within 3 months. MRONJ should be considered as a hypothesis in the case of odontalgia and a patient's history of antiresorptive and antiangiogenic therapies. Furthermore, monitoring patients with dental implants in the mandible through detailed clinical and imaging evaluation is required.

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The present review summarizes the findings from human histological studies conducted over the past 20 years at the University of Guarulhos, Brazil, examining the impact of various implant surface topographies and smoking on peri-implant bone response. Seven different implant surfaces were evaluated in 90 partially or completely edentulous individuals using a total of 123 micro-implants. Histometric parameters, including bone-implant contact (BIC%), bone area within the threads (BA%), and bone density (BD), were assessed after an 8-week healing period. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses were also performed. Results showed that treated surfaces, regardless of the treatment type, consistently demonstrated better histometric outcomes compared to machined surfaces. Anodized surfaces and those subjected to airborne particle abrasion, followed by acid etching, exhibited higher BIC% values than machined surfaces in smoker patients. Smoking reduced BIC% around anodized implants. The presence of inflammatory cells was observed adjacent to the peri-implant soft tissue on some treated surfaces. In conclusion, implant surface topography significantly influences early bone response under unloaded conditions, with treated surfaces promoting better human bone tissue response than machined surfaces. However, smoking negatively impacts peri-implant bone healing, emphasizing the importance of smoking cessation for optimal osseointegration.

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The necessity for regenerating peri-implant and periodontal tissues is increasingly apparent. Periodontal diseases can result in a significant loss of clinical attachment level, and tissue regeneration stands as the ultimate goal of periodontal therapy. With the rise of osseointegration, the prosthetic rehabilitation of missing teeth using dental implants has surged, leading to a frequent need for alveolar bone regeneration around implants. This review assessed studies reporting various sources of mesenchymal stromal/stem cells (MSC) and their potential in regenerating periodontal and peri-implant bone tissue. A search was conducted across seven databases spanning the past decade. Three authors independently screened all identified titles and abstracts for eligibility, generating tables to summarize included studies in animals and humans separately. A total of 55 articles were chosen for final evaluation, showcasing five origins of MSC used in humans and animals for regenerating periodontal tissues and peri-implant bone, using different types of scaffolds. Overall, research from the past decades supports the effectiveness of MSC in promoting periodontal and peri-implant regeneration. However, the impact of MSC on regenerative therapies in humans is still in its initial stages. Future research should optimize MSC application protocols by combining techniques, such as the use of nanomedicine and 3D printing for tissue engineering. Clinical studies should also understand the long-term effects and compare MSC therapies with current treatment modalities. By addressing these areas, the scientific community can ensure that MSC therapies are both safe and effective, ultimately enhancing therapeutic strategies and treatment outcomes in Periodontology and Implantology.

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Dental implants have become the most effective treatment option for replacing missing teeth, worldwide. The popularity and demand for dental implants are continually increasing. Nevertheless, its complications are undeniable. Peri-implant diseases, including peri-implant mucositis and peri-implantitis, are a multifaceted clinical condition. Therefore, it is in the best interest to optimize the management of peri-implantitis, and there are still numerous methods to treat and manage infections in the vicinity of dental implants. The main goal of peri-implantitis treatment is to arrest disease progression, eliminate infection, and reconstruct damaged tissues around the implant. The clinical evidence on treating peri-implantitis that is available in PubMed was reviewed. Additionally, we presented the most comprehensive management strategies. As a result, numerous clinical trials recommended mechanical debridement and local administration of antimicrobial agents as well as topical oxygen therapy to mitigate bacterial biofilm and manage infection. The regenerative (bone grafting) approach for the treatment of peri-implantitis is another effective method. Finally, implant surface engineering can address high antibacterial efficacy and site-specific biofilm reduction.

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The aim of this study is review the efficacy of different techniques of home care and professional care for long-term implant maintenance, when compared with their respective standard procedures (regular brushing or mechanical debridement with curette), in changing clinical parameters, such as bleeding on probing, probing depth, plaque score and gingival index, as reported in randomized clinical trials. MATERIALS AND METHODS: A systematic literature search of randomized clinical trials was performed using the PubMed (MEDLINE), EMBASE and Cochrane library databases. A qualitative review was conducted to compare all the different techniques of home care and professional care for long-term implant maintenance. RESULTS: Initial search involved a total of 816 articles, 233 via Pubmed (Medline), 306 via the Cochrane Library, and 483 via EMBASE, while an additional 16 articles were collected through manual screening. A total of 29 articles were assessed by full-text read for eligibility and a final count of 13 studies were included in systematic review. The results of the risk of bias assessment for the included RCTs according to the 'RoB 2'. Results favored glycine powder air-polishing and ultrasonic devices over traditional mechanical debridement with curettes in improving clinical parameters. In at-home care, water flossers with chlorhexidine were able to reduce inflammation. CONCLUSIONS: Evidence points towards the use of glycine powder air-polishing and the use of ultrasonic devices for reduction of inflammation around implants, and for home care, many existing techniques seem to be able to control tissue inflammation, but the use of chlorhexidine in water-flossers seems to be a promising strategy.

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OBJECTIVE: Evaluate the load mini-implants exert on the artificial bone when expanding the MARPE EX in three different extension arm configurations. METHODS: A device simulating the human palate was fabricated and attached to a universal testing machine, for conducting tests with different MARPE expanders (n=5): non-adjustable/control (MARPE SL, Peclab) or with low, intermediate, and high extender arms (MARPE EX, Peclab). The expanders were manually activated until failure of the device occurred, and maximum load values were recorded. Load averages were also calculated for every five activations until the twentieth activation. RESULTS: The generalized linear mixed model for repeated measures over time showed that there was significant increase in load with activations for all expanders (p=0.0004). Up to the twentieth activation, the expander with low extender arms presented higher load than the others, while the expander with high extender arms showed lower load values (p<0.05). There was no significant difference among expanders regarding the number of activations (p=0.0586), although there was a trend towards fewer activations until fracture for the control expander. It was observed that the higher the configuration, the lower the force the mini-implants delivered to the bone. The control expander provided a force magnitude similar to that of the adjustable expander when positioned at the intermediate height. CONCLUSIONS: The activation load of MARPE expanders is influenced by the type of presentation of the extensor arms, with higher configurations resulting in lower force delivered by the mini-implants to the bone.

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STATEMENT OF PROBLEM: The biomechanical stability of the implant-prosthesis assembly and its maintenance under function is a determining factor in the success of implant prosthesis rehabilitation, but studies of different angular tapers are lacking. PURPOSE: The purpose of this in vitro study was to evaluate the axial displacement and torque loss of prosthetic abutments with Morse-type connections of different angular tapers after thermomechanical cycling by using microcomputed tomography (µCT) and a digital torque wrench. MATERIAL AND METHODS: Eighteen Ø3.5×11.5-mm implants were embedded in polyvinyl chloride cylinders, and the 3 different types of abutments (n=6) with angular tapers of 11.5 degrees - Alvim Cone Morse (ACM-11.5), 16.0 degrees - Helix Gran Morse (HGM-16), and 24.0 degrees - Nobel Replace Conical Connection (NRC-24) were installed with the torque recommended by the manufacturers. To calculate the axial displacements of the abutments about the implants, zirconia maxillary canine crowns were fabricated using a computer-aided design and computer-aided manufacturing (CAD-CAM) system and cemented onto the abutments. Before and after thermomechanical cycling, the assemblies were scanned using microtomography (micro-CT) to assess axial displacement, and the torque losses were calculated after the abutments were finally unscrewed. A load of 100 N, frequency of 2 Hz, and 106 cycles with temperature variation of 5 °C to 55 °C were used for the thermomechanical cycling. Analysis of variance and the Tukey post hoc test (α=.05) were used for analysis. RESULTS: A significant difference was observed between the abutments for axial displacement, measured after thermomechanical cycling (P=.002). The ACM-11.5 abutment showed the highest mean value (134.1 ±58.7 µm), different from HGM-16 (63.3 ±26.1 µm) (P=.013) and NRC-24 (42.7 ±8.7 µm) (P=.002); the 2 latter groups were similar to each other (P=.618). For the torque losses, no significant difference was found among the abutments (P=.928), but there were significant differences for the thermomechanical cycling (before and after) (P<.001) in that the loss of torque was greater after thermocycling. CONCLUSIONS: The smaller the taper angle of the Morse-type prosthetic abutment, the greater its axial displacement, and the thermomechanical cycling significantly reduced pretorque, regardless of taper.

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OBJECTIVE: To assess the effect of a blooming artifact reduction (BAR) filter on cone beam computed tomography (CBCT) images in the dimensional analysis of dental implants. STUDY DESIGN: Six types of implants (n = 5 for each type) composed of titanium (3 types), titanium-zirconia alloy, zirconium oxide, and titanium-aluminum-vanadium alloy, and made with 2 manufacturing processes (milled and printed) were individually installed in a bovine rib block according to the manufacturer's protocol. CBCT images were acquired with i-CAT and Carestream scanners, randomized, and analyzed without and with the e-Vol DX BAR filter (60 images for each scanner). Implant length, diameter, and thread-to-thread distance were measured by two radiologists, with a stereomicroscopic image of each implant as the reference standard for calculation of distortion in measurements. Repeated measures ANOVA with Bonferroni corrections and intraclass correlation coefficients (ICC) were applied (α = 0.05). RESULTS: The BAR filter significantly reduced distortion in various parameters for specific implants, aligning closely with stereomicroscopic measurements. Titanium and printed implants showed reduced dimensional distortion regardless of BAR filter use. Carestream measurements presented smaller dimensional differences than i-CAT for most implants and parameters, especially without BAR (P < .05). Interexaminer reliability was good to excellent, with ICC ranging from 0.80 to 0.95. CONCLUSIONS: The BAR filter can enhance implant dimensional analysis, although variations based on implant material and manufacturing process were observed.

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The aim of this study was to evaluate the wettability and adhesion of self-organized TiO2 nanotubes formed on the surface of 8 commercially pure titanium (CP-Ti) disks and 12 dental implants (n = 12) by anodization in a glycerol-H2O (50-50 v/v) electrolyte containing NH4F. Two disk specimens were not submitted to anodization (controls). The nanotubes thus obtained had average dimensions of 50 nm in diameter by 900 nm in length. The treated disk specimens were stored for 2, 14 and 35 days (n = 2), and the wettability of their surfaces was evaluated with a goniometer at the end of each storing period. The adhesion of nanotubes to titanium was evaluated by field emission scanning electron microscopy after subjecting the 12 implants to a simulation of clinical stress in two-part synthetic bone blocks. After installing the implants with the application of an insertion torque, the two halves of the block were separated, and the implants were removed. The nanotubes remained adhered to the substrate, with no apparent deformation. The contact angles after 14 days and 35 days were 16.47° and 17.97°, respectively, values significantly higher than that observed at 2 days, which was 9.24° (p < 0.05). It was concluded that the method of anodic oxidation tested promoted the formation of a surface suitable for clinical use, containing nanotubes with levels of wettability and adhesion to titanium compatible with those obtained by other methods found in the literature. The wettability, however, did not prove stable over the tested storage periods.

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BACKGROUND: To verify the influence of macrogeometry with healing chambers on the osseointegration of dental implants by analyzing implant stability quotient (ISQ) and evaluate the correlation between insertion torque and ISQ insertion with different macrogeometries. METHODS: In total, 26 implants were installed in the posterior mandible of eight patients with sufficient bone height for the installation of implants measuring 3.5 mm in diameter and 9.0 mm in length. The implants were categorized according to two types of macrogeometry: a test group (GT) with 13 conical implants with healing chambers and a control group (GC) with 13 conical implants with conventional threads. To insert the implants, a bone drilling protocol was used up to a diameter of 3 mm with the last helical bur. The insertion torque of the implants was evaluated, followed by the measurement of ISQ at 0 (T-0), 7 (T-7), 14 (T-14), 21 (T-21), 28 (T-28), and 42 (T-42) days. RESULTS: The mean insertion torque was 43 Ncm in both groups, without a significant difference. Moreover, no significant difference in the ISQ values was found between the groups at different time points (p > 0.05), except at T-7 (GT = 69.87±1.89 and GC = 66.48±4.49; p = 0.01). Although there was no significant difference, ISQ median values were higher in the GT group than GC group at 28 days (GT = 67.98 and GC = 63.46; p = 0.05) and 42 days (GT = 66.12 and GC = 60.33; p = 0.09). No correlation was found between the insertion torque and ISQ insertion (p > 0.05). CONCLUSION: Furthermore, implants with a 3.5 mm diameter macrogeometry, with or without healing chambers, inserted with a drilling protocol up to 3 mm in diameter of the last helical bur, led to a similar secondary stability, with no difference in ISQ values. Although, implants with healing chamber demonstrates ascending values in the graph of ISQ, having a trend of faster osseointegration than implants without healing chambers. Both macrogeometries provide a similar primary stability to implants. TRIAL REGISTRATION: This study was registered retrospectively in ReBec (brazilian registry of clinical trials) under the number RBR-96n5×69, on the date of 19/06/2023.

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