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1.
J Arthroplasty ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39019413

RESUMO

BACKGROUND: The first generation of titanium nitride (TiN) coatings for orthopaedic implants was clinically introduced in the 1990s because of their promising biocompatibility, wear resistance, and corrosion resistance. This study evaluated the in vivo performance of early TiN-coated knee and hip implants, focusing on the bearing surfaces and mechanisms of in vivo damage. METHODS: There were 13 TiN-coated implants (5 knee and 8 hip) retrieved from 8 patients as part of a multi-institutional implant retrieval program. The average implantation time was 4.25 years for knees and 17.5 years for hips. Implant revisions occurred for various reasons, including polyethylene wear, loosening, pain, infection, and instability. Components were examined using a semiquantitative scoring method, and surface roughness measurements were performed using white-light interferometry. Surface morphology, chemistry, and particle characterization were also assessed by scanning electron microscopy. RESULTS: For hips, mild corrosion was found on femoral head tapers, along with severe scratching on certain femoral heads. Knee implants exhibited low burnishing and scratching for both mechanisms. Roughness measurements (Sa) were 37.3 nm (interquartile range = 22.0 to 62.4) for hips and 85.3 nm (interquartile range = 66.3 to 110) for knees. The observed scratch depth in both hip and knee implants due to third-body particles ranged from 0.3 to 1.3 µm. The coating coverage remained intact in the majority of the implants, with 2 cases of small, localized cohesive chipping and substrate exposure. CONCLUSIONS: The results of this study confirm the potential in vivo durability of early TiN coatings and will be useful in benchmarking wear tests for modern TiN-coated orthopaedic implants.

2.
Artigo em Inglês | MEDLINE | ID: mdl-39058351

RESUMO

PURPOSE: This study investigated the effect of implant vertical positioning within alveolar ridge preservation (ARP) sites on implant stability quotient (ISQ) values, which were measured 10 weeks post-implantation. METHODS: Patients who underwent ARP using collagenized deproteinized bovine bone mineral, followed by implant placement in the posterior area, were divided into 2 groups: the within-ARP group and the beyond-ARP group. In the within-ARP group, osteotomy and implant placement occurred within the ARP boundary. In contrast, in the beyond-ARP group, these procedures were performed beyond the ARP boundary, incorporating 3 mm of pristine bone at the implant's apex. Bone quality was assessed by tactile sense, and both insertion torque during implant surgery and ISQ values at 10 weeks post-implant surgery were measured. Multiple linear regression analysis and Pearson correlation analysis were used to explore the relationship between insertion torque and ISQ values. RESULTS: In total, 30 ARP sites in 28 patients were analyzed. There was no significant difference in bone quality, as determined by tactile sense, between the within-ARP and beyond-ARP groups. At the time of implant placement, the beyond-ARP group exhibited a higher insertion torque (33.33±13.39 Ncm) compared to the within-ARP group (17.08±11.17 Ncm). However, the ISQ values were similar between the 2 groups 10 weeks after implant placement. A positive correlation between insertion torque and ISQ values was confirmed at 10 weeks post-implant. CONCLUSIONS: The engagement of pristine bone may facilitate high insertion torque during the placement of implants in ARP sites. Nevertheless, by 10 weeks post-implantation, the ISQ values were found to be comparable, irrespective of the implant's position.

3.
Artigo em Inglês | MEDLINE | ID: mdl-39058352

RESUMO

PURPOSE: The nasopalatine canal (NPC) is one of the most significant anatomical markers in the anterior maxillary region. Its location is quite important, especially for implant placement. Therefore, the purpose of this study was to use cone-beam computed tomography (CBCT) to evaluate the morphology, size, and anatomic variations of the NPC. METHODS: A total of 150 individual CBCT images were assessed in various sections to evaluate the dimensions, morphology, and extent of the NPC. Reformatted sagittal images were chosen to classify the shape and course of the canal. The Student's t-test, the χ² test, and Pearson correlation coefficients were used. RESULTS: The NPC was longer in males than in females, and the mediolateral diameter of the canal was greater in older adults. In sagittal sections, the canal predominantly exhibits a cylindrical shape, while a spindle shape is the least common. In coronal sections, a single shape is most frequently observed, with a Y-shape being the least common. Regarding the orientation of the canal, slanted canals are more prevalent, whereas vertically curved canals are rare. Typically, 2 canal openings are observed, with 4 openings being the least common. CONCLUSION: The current study highlights the challenges associated with identifying the anatomical appearance and variations of the NPC. Consequently, possessing a thorough understanding of this anatomy is essential before undertaking any surgical procedures, such as implant placement. This knowledge helps prevent complications such as nerve injury-related loss of sensation, bleeding due to blood vessel injury, and the development of a nasopalatine duct cyst following trauma to the canal during surgery.

4.
Artigo em Inglês | MEDLINE | ID: mdl-39058350

RESUMO

PURPOSE: This review was conducted to systematically assess the impact of bisphosphonates (BPs) and denosumab, used as anti-resorptive therapies, on the incidence of dental implant failure. METHODS: Electronic and manual searches were performed in accordance with the described search protocol. Only articles that met the inclusion criteria were selected. The primary outcome was implant failure, while secondary outcomes included biological complications and comorbidities. Following data extraction, a quality assessment and meta-analysis were conducted. RESULTS: Fourteen eligible studies were included in the analysis following a qualitative evaluation. BP administration, regardless of the timing of anti-resorptive therapy, did not significantly increase the risk of implant failure (odds ratio [OR], 1.40; 95% confidence interval, 0.83-2.34). Subgroup analysis revealed a slightly higher, although statistically insignificant, risk of failure in patients with a follow-up period of 3 years or more compared to those with a follow-up duration of less than 3 years (with ORs of 2.82 and 1.53, respectively). Due to a lack of eligible studies, a meta-analysis for denosumab could not be conducted. CONCLUSIONS: Our findings suggest that BP treatment does not compromise the survival of dental implants. Specifically, in patients with osteoporosis, implant failure rates were not significantly influenced by the administration of BPs before the placement of dental implants, suggesting that low-dose BP therapy may not contraindicate implant placement. Nevertheless, regular check-ups and maintenance periodontal treatment must not be neglected, and concomitant biological factors should be considered to ensure the long-term success of implant rehabilitation.

5.
Artigo em Inglês | MEDLINE | ID: mdl-39056305

RESUMO

OBJECTIVE: To assess the clinical, radiographic and patient-reported outcomes (PROMs) of posterior zirconia and titanium implants at 1 year of implant loading. MATERIALS AND METHODS: Forty-two patients with two adjacent missing teeth were enrolled in a randomized controlled trial with a within-subject controlled design. Each patient received one zirconia (Zr) and one titanium (Ti) implant, with the mesial and distal positions randomized. The implant restoration consisted of multiple layered zirconia, with the buccal aspect veneered. In group Zr, the restoration was intraorally cemented onto the one-piece Zr implant, whereas in group Ti, the restoration was extraorally cemented onto the titanium base abutment and intraorally screw-retained onto the Ti implant. Examinations were performed following restoration delivery at baseline (BL) and at 1 year. Measurements included clinical parameters, radiographic outcomes (MBL) and PROMs. RESULTS: Bleeding on probing showed an increase from BL to 1 year (34 ± 30% for Zr; 25 ± 21% for Ti). MBL remained stable with minimal changes from BL to 1 year, measuring 0.1 ± 0.4 mm (mean ± SD) for Zr and -0.1 ± 0.7 mm for Ti. Veneering fractures were the most frequent technical complication and amounted to 17.5% in group Zr and 5% in group Ti (p = .100). Patients preferred Zr implants for their soft tissue color, with a significant difference in perception between patients and clinicians (p < .017). CONCLUSION: The study showed that both Zr and Ti implants had similar clinical outcomes, despite a high prevalence of mucositis and a few technical complications. Both implant types demonstrated stable marginal bone levels and similar patient-reported outcome measures.

6.
Clin Exp Dent Res ; 10(4): e939, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39039934

RESUMO

OBJECTIVES: The primary aim of this cross-sectional study was to investigate the association between prosthesis design and peri-implant mucosa dimensions and morphology. The secondary aim was to investigate associations between mucosal dimensions and the presence of mucositis. MATERIALS AND METHODS: Forty-seven patients with 103 posterior bone level implants underwent clinical and radiographic examination, including cone beam computer tomography and intraoral optical scanning. Three-dimensional models for each implant and peri-implant mucosa were constructed. Vertical mucosa height (TH), horizontal mucosa width at implant platform (TW), and 1.5 mm coronal of the platform (TW1.5), as well as mucosal emergence angle (MEA), deep angle (DA), and total contour angle (TA) were measured at six sites for each implant. RESULTS: There was a consistent correlation between peri-implant mucosa width and height (ß = 0.217, p < 0.001), with the width consistently surpassing height by a factor of 1.4-2.1. All three angles (MEA, DA, TA) were negatively associated with mucosa height (p < 0.001), while DA was negatively associated with mucosa width (TW1.5) (p < 0.001, ß = -0.02, 95% CI: -0.03, -0.01). There was a significant negative association between bleeding on probing (BoP) and mucosa width at platform (OR 0.903, 95% CI: 0.818-0.997, p = 0.043) and 1.5 coronal (OR 0.877, 95% CI: 0.778-0.989, p = 0.033). Implants with less than half sites positive for BoP (0-2/6) had significantly higher mucosa height (OR 3.51, 95% CI: 1.72-7.14, p = 0.001). CONCLUSIONS: Prosthesis design can influence the dimensions of the peri-implant mucosa, with wider emergence profile angles associated with reduced peri-implant mucosa height. In particular, a wider deep angle is associated with reduced mucosa width in posterior sites. Reduced peri-implant mucosa height and width are associated with more signs of inflammation. TRIAL REGISTRATION: Registered in Thai Clinical Trials Registry: http://www.thaiclinicaltrials.org/show/TCTR20220204002.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Implantes Dentários , Mucosa Bucal , Humanos , Feminino , Masculino , Estudos Transversais , Pessoa de Meia-Idade , Implantes Dentários/efeitos adversos , Mucosa Bucal/patologia , Adulto , Idoso , Planejamento de Prótese Dentária , Estomatite/etiologia , Estomatite/patologia , Imageamento Tridimensional , Implantação Dentária Endóssea/métodos , Implantação Dentária Endóssea/efeitos adversos
7.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 42(3): 372-381, 2024 Jun 01.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-39049659

RESUMO

OBJECTIVES: This test aimed to investigate the factors affecting the locking force between the implant and abutment and the amount of abutment subsidence in pure Morse taper connection implant systems. METHODS: With reference to the Bicon implant abutment connection design, different types of implant specimens and their corresponding types of abutments were fabricated. The implant-abutment locking taper was uniformly 1.5°. The locking depths were 1.0, 2.0, and 3.0 mm. The diameters of the locking column were 2.5, 3.0, and 3.5 mm. The thicknesses of the outer wall of the implant were 0.15 and 0.30 mm. The loading forces of the testing machine were 200, 300, and 400 N. At least 10 specimens of each group of implant-abutment were used. All specimens were loaded in the same manner using a universal testing machine (finger pressure + specified loading force, five times). The total height of the implant-abutment was measured before finger pressure, after finger pressure, and after the testing machine was loaded for five times to calculate the amount of sinking of the abutment. Finally, the implant and abutment were pulled apart using the universal testing machine, and the subluxation force was observed and recorded. RESULTS: The test loading force, locking depth, and locking post diameter had an effect on the implant-abutment locking force and abutment subsidence. The implant-abutment locking force increased with the increase in the test loading force, locking depth, and locking post diameter (R=0.963, 0.607, and 0.372, respectively), with the test loading force having the most significant effect. Abutment subsidence increased with the increase in test loading force (R=0.645) and decreased with the increase in locking depth and locking post diameter (R=-0.807 and -0.280, respectively), with locking depth having the most significant effect on abutment subsidence. No significant correlation was found between the thickness of the outer wall of the implant and the change in the magnitude of the implant-abutment locking force. However, an increase in the thickness of the outer wall of the implant decreased the amount of abutment subsidence, which was inversely correlated. CONCLUSIONS: The locking force of the implant-abutment can be increased by adjusting the design of the pure Morse taper connection implant⁃abutment connection, increasing the locking depth and locking post diameter, and increasing the amount and number of times the abutment is loaded during seating. Problems, such as loosening or detachment of the abutment, can be reduced. The recommended abutment to be loaded should be no less than five times during seating to prevent the abutment from sinking and causing changes in the occlusal relationship in the later stages. Preliminary occlusal adjustments should only be conducted in the early stages of the use of temporary restorations, and final restorations and occlusal adjustments are recommended to be performed after using the abutment for a period of time.


Assuntos
Dente Suporte , Projeto do Implante Dentário-Pivô , Análise do Estresse Dentário , Implantes Dentários , Estresse Mecânico , Humanos
8.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 42(3): 382-393, 2024 Jun 01.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-39049660

RESUMO

OBJECTIVES: This study aimed to systematically compare the effects of flapless and flapped implantations on the surrounding soft tissues of dental implants. METHODS: Nine databases were searched, including PubMed, Embase, Cochrane Library, Web of Science, Clinical Trials, OpenGrey, OpenDoar, Scopus, and Ovid, from January 1, 2013, to August 27, 2023. Randomized controlled trials comparing flapless implantation with flapped implantation for restoration of missing teeth were included. Meta-analysis was conducted on studies that met the inclusion criteria by using RevMan 5.3 and Stata 14.0. RESULTS: A total of 1 245 articles were retrieved, and 17 studies were ultimately included. The results of Meta-analysis showed that flapless implantation resulted in better healing of the soft tissues around the dental implants than flapped implantation. Moreover, flapless implantation showed superior changes in implant success rate [mean difference (MD)=1.06, 95% confidence interval (CI) (1.02, 1.10), P=0.004], the width of keratinized gingival changes [MD=0.10, 95%CI (0.00, 0.20), P=0.04], and probing depth [MD=-0.60, 95%CI (-0.67, -0.53), P<0.000 01], with statistically significant differences. The final combined results of modified plaque index [standardized mean difference (SMD)=-0.41, 95%CI (-0.81, 0.00), P=0.05] and modified sulcus bleeding index [SMD=-0.44, 95%CI (-0.78, -0.10), P=0.01] showed superiority over flapped implantation. The papillary presence index was higher in the flapless implantation group than in the flapped implantation group. No statistically significant differences were observed in plaque index and gingival indices changes between the two groups. CONCLUSIONS: Flapless implantation can achieve higher implant success rate, smaller changes in the width of keratinized gingival, and smaller probing depths than flapped implantation. It also has advantages in terms of modified plaque index, modified sulcus bleeding index, and papillary presence index.


Assuntos
Gengiva , Retalhos Cirúrgicos , Humanos , Gengiva/cirurgia , Implantes Dentários , Ensaios Clínicos Controlados Aleatórios como Assunto , Cicatrização , Implantação Dentária/métodos
9.
Audiol Res ; 14(4): 581-592, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-39051193

RESUMO

(1) Background: Cochlear implants (CIs) are widely applied to recover audition for patients with severe degrees of or total hearing loss. Electrical stimulation using the electrically evoked ABR (E-ABR) can be recorded in CI recipients through the device. This work was designed to study E-ABR recorded individually from different channels located at the apical, middle, and basal cochlear regions in comparison to their simultaneous separated or adjacent combined recordings. (2) Methods: This study included 17 children fitted with unilateral cochlear implants. All children were subjected to impedance measurement, electrical compound action potentials (ECAP), and E-ABR recording of three channels located at the apical, middle, and basal cochlear regions. This was followed by simultaneous E-ABR recording of the three "separated" channels in comparison to E-ABR recording from three adjacent channels located at the middle cochlear region. (3) Results: Similar E-ABR latencies and amplitudes were found using either individual or simultaneously separated or adjacent combined recording. However, the mean amplitude measures of E-ABR for combined adjacent channels showed a positive correlation with the applied current level. (4) Conclusions: Combined E-ABR recording from adjacent channels is a faster and more reliable technique that can be used effectively without compromising the results of the recorded E-ABR.

10.
Audiol Res ; 14(4): 649-658, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39051199

RESUMO

BACKGROUND: Cochlear implantation (CI) has proven to be a highly effective method for rehabilitating individuals with severe to profound hearing loss. However, challenges persist, particularly in cases where CI failure necessitates re-implantation. This study aims to address the gap in understanding the knowledge and practices of audiologists in the UK regarding cochlear re-implantation through a comprehensive questionnaire survey. METHODS: A bespoke questionnaire was distributed to audiologists working with CI across the UK. The survey, which included multiple-choice items, open-text responses, and visual analogue scales, was made accessible via an online link shared through professional bodies, email groups, and social media platforms. RESULTS: The survey received 27 responses, predominantly from female audiologists (71.4%), with significant representation from London (28.6%) and the East of England (21.4%). A majority of respondents had over 16 years of CI experience (35.7%) and held a master's degree (60.7%). Key reasons for CI re-implantation included electrode failure (82.1%) and hermetic seal failure (60.7%). While respondents showed strong confidence in counselling (88.8%) and managing re-implanted devices (84.6%), there was a noted variation in opinions regarding the need for additional training in intraoperative measures. CONCLUSION: This survey highlights the current practices and training needs of UK audiologists in CI re-implantation. This underscores the importance of targeted training to fill knowledge gaps and improve clinical care during CI re-implantation, ultimately enhancing outcomes for both audiologists and CI recipients.

11.
Int J Periodontics Restorative Dent ; 0(0): 1-25, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39058946

RESUMO

This prospective case series aimed to evaluate the feasibility of using a volume collagen matrix for soft tissue augmentation to increase mucosal thickness in single implants in smokers who consume more than 10 cigarettes per day. Participants had single submerged implants necessitating soft tissue thickening. Soft tissue augmentation was done using a collagen matrix in the second-stage surgery. The primary outcome was soft tissue thickness at 90 days post-surgery. Secondary outcomes included median thickness at 30 and 60 days, changes in buccal soft tissue profile (digital measurements) at 30, 60, and 90 days, and oral health-related quality of life using OHIP-14 up to 90 days post-surgery. Pain levels via VAS scale and adverse effects were also assessed. Ten participants (4 men, 6 women) aged 45.2 ± 13.18 years initially smoked 10-20 cigarettes daily (average: 14.70 ± 3.47 cigarettes/day). After 90 days, median soft tissue thickness increased to 3.00 (2.00;3.00) mm. Buccal soft tissue profile (median change in ROI) increased by 0.40 (0.25;0.62) mm at 90 days. Pain levels decreased, and oral health-related quality of life improved significantly. No complications were reported. The collagen matrix significantly augmented buccal soft tissue thickness at implant sites in smokers (>10 cigarettes/day), with favorable outcomes and no complications.

13.
J Dent ; 148: 105264, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39053878

RESUMO

OBJECTIVES: To evaluate the bone changes around equicrestal and subcrestal implants, analyzing the effect of abutment height [short abutments (SA < 2 mm) and long abutments (LA > 2 mm)] and the three components of the peri­implant soft-tissue phenotype. METHODS: Twenty-six patients received 71 implants that were placed according to supracrestal tissue height (STH) in an equicrestal (n = 17), shallow subcrestal ≈1 mm (n = 33), or deep subcrestal ≈2 mm (n = 21) position. After 3 months of healing, rehabilitation was completed using metal-ceramic crowns on multi-unit abutments of 1.5 mm, 2.5 mm, or 3.5 mm in height, depending on the prosthetic space and STH. Longitudinal clinical parameters (STH, mucosal thickness, and keratinized mucosa width) and radiographic data [bone remodelling and marginal bone loss (MBL)] were collected at 3, 6, 12, and 24 months postsurgery. RESULTS: The gain in STH was significantly greater around the implants placed in a subcrestal ≈2 mm position. After 2 years, the mean change in bone remodelling in the SA group was significantly greater than in the LA group. According to the multiple linear regression, bone remodelling depends primarily on abutment height (ß = -0.43), followed by crestal position (ß = 0.34), and keratinized mucosa width (ß = -0.22), while MBL depends on abutment height (ß = -0.37), and the patient's age (ß = -0.36). CONCLUSIONS: Implants placed in an equicrestal or subcrestal ≈1 mm position with LA undergo less bone remodelling, while the lowest level of MBL occurs in subcrestal ≈2 mm implants with LA. Differing soft-tissue thicknesses combined with the use of either SA or LA produced significant intergroup differences in bone remodelling and MBL. CLINICAL SIGNIFICANCE: Abutment height is the most powerful predictor variable affecting bone remodelling and MBL. Depending on the dimensions of the peri­implant soft-tissue phenotype, placing the implants subcrestally may also be a viable option to decrease bone remodelling and, consequently, reduce MBL. CLINICAL TRIAL REGISTRATION: identification number: NCT05670340.

14.
BMC Oral Health ; 24(1): 842, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39054434

RESUMO

BACKGROUND: The question of whether antibiotic prophylaxis should be administered routinely for dental implant surgery is unresolved. Despite the lack of conclusive supportive evidence, antibiotics are often administered to reduce the risk of infection, which could lead to early implant failure. Increasing antibiotic resistance is a major concern and it is therefore important to reduce the overall use of antibiotics, including in dentistry. The aim of the present systematic review and meta-analysis was to evaluate the efficacy of preoperative antibiotics in preventing early implant failure, in overall healthy patients undergoing dental implant surgery. METHODS: An electronic search was undertaken of PubMed (Medline), Web of Science and the Cochrane Library up to October 1st, 2023, to identify randomized clinical trials (RCTs). All RCTs comparing antibiotic prophylaxis with no antibiotics/placebo in overall healthy patients receiving dental implants were included. The primary outcome was patients with early implant failure. Risk of bias was assessed, data were extracted, a meta-analysis was done, and GRADE certainty-of-evidence ratings were determined. The risk ratio (RR), the risk difference (RD) and 95% confidence intervals (CI) were estimated. RESULTS: After removal of duplicates, 1086 abstracts were screened, and 17 articles were reviewed in full text. Seven RCTs with moderate or low risk of bias and with a total of 1859 patients and 3014 implants were included in the meta-analysis. With reference to early implant failure at patient level, the meta-analysis failed to disclose any statistically significant difference (RR: 0.66, 95% CI: 0.30-1.47) between antibiotic prophylaxis and a placebo. The risk difference was -0.007 (95% CI: -0.035-0.020) leading to a number needed to treat (NNT) of 143. CONCLUSION: Antibiotic prophylaxis for dental implant surgery does not seem to have any substantial effect on early implant failure ( ). The results do not support routine antibiotic prophylaxis for dental implant surgery.


Assuntos
Antibioticoprofilaxia , Falha de Restauração Dentária , Humanos , Implantes Dentários , Antibacterianos/uso terapêutico , Antibacterianos/administração & dosagem , Implantação Dentária Endóssea/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto , Infecção da Ferida Cirúrgica/prevenção & controle
15.
Biology (Basel) ; 13(7)2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-39056666

RESUMO

This study evaluated the bone incorporation process of a screw-shaped internal fixation device made of poly (L-lactide-co-D, L-lactide) (PLDLLA). Thirty-two male Wistar rats received 32 fixation devices (2 mm × 6 mm) randomly assigned to either the right or left tibia and one implant in each animal. After 7, 14, 28, and 42 days, the rats were euthanized and the specimens were subjected to microtomographic computed tomography (microCT) and histomorphometric analyses to evaluate bone interface contact (BIC%) and new bone formation (NBF%) in cortical and cancellous bone areas. The animals euthanized on days 28 and 42 were treated with calcein and alizarin red, and confocal LASER microscopy was performed to determine the mineral apposition rate (MAR). Micro-CT revealed a higher percentage of bone volume (p < 0.006), trabecular separation (p < 0.001), and BIC in the cortical (p < 0.001) and cancellous (p = 0.003) areas at 28 and 42 days than at 7 and 14 days. The cortical NBF at 42 days was greater than that at 7 and 14 days (p = 0.022). No statistically significant differences were observed in cancellous NBF or MAR at 28 and 42 days. Based on these results, it can be seen that the PLDLLA internal fixation device is biocompatible and allows new bone formation around the screw thread.

16.
Biology (Basel) ; 13(7)2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39056725

RESUMO

(1) Objective: The aim of this study was to assess the biological behavior of bone tissue on a machined surface (MS) and modifications made by a laser beam (LS) and by a laser beam incorporated with hydroxyapatite (HA) using a biomimetic method without thermic treatment (LHS). (2) Methods: Scanning electron microscopy coupled with energy-dispersive X-ray spectrometry (SEM/EDX) was performed before and after installation in the rabbit tibiae. A total of 20 Albinus rabbits randomly received 30 implants of 3.75 × 10 mm in the right and left tibias, with two implants on each surface in each tibia. In the animals belonging to the 4-week euthanasia period group, intramuscular application of the fluorochromes calcein and alizarin was performed. In implants placed mesially in the tibiofemoral joint, biomechanical analysis was performed by means of a removal torque (N/cm). The tibias with the implants located distally to the joint were submitted for analysis by confocal laser microscopy (mineral apposition rate) and for histometric analysis by bone contact implant (%BIC) and newly formed bone area (%NBA). (3) Results: The SEM showed differences between the surfaces. The biomechanical analysis revealed significant differences in removal torque values between the MSs and LHSs over a 2-week period. Over a 4-week period, both the LSs and LHSs demonstrated removal torque values statistically higher than the MSs. BIC of the LHS implants were statistically superior to MS at the 2-week period and LHS and LS surfaces were statistically superior to MS at the 4-week period. Statistical analysis of the NBA of the implants showed difference between the LHS and MS in the period of 2 weeks. (4) Conclusions: The modifications of the LSs and LHSs provided important physicochemical modifications that favored the deposition of bone tissue on the surface of the implants.

17.
Biomimetics (Basel) ; 9(7)2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-39056849

RESUMO

Currently, titanium and its alloys have emerged as the predominant metallic biomaterials for orthopedic implants. Nonetheless, the relatively high post-operative infection rate (2-5%) exacerbates patient discomfort and imposes significant economic costs on society. Hence, urgent measures are needed to enhance the antibacterial properties of titanium and titanium alloy implants. The titanium dioxide nanotube array (TNTA) is gaining increasing attention due to its topographical and photocatalytic antibacterial properties. Moreover, the pores within TNTA serve as excellent carriers for chemical ion doping and drug loading. The fabrication of TNTA on the surface of titanium and its alloys can be achieved through various methods. Studies have demonstrated that the electrochemical anodization method offers numerous significant advantages, such as simplicity, cost-effectiveness, and controllability. This review presents the development process of the electrochemical anodization method and its applications in synthesizing TNTA. Additionally, this article systematically discusses topographical, chemical, drug delivery, and combined antibacterial strategies. It is widely acknowledged that implants should possess a range of favorable biological characteristics. Clearly, addressing multiple needs with a single antibacterial strategy is challenging. Hence, this review proposes systematic research into combined antibacterial strategies to further mitigate post-operative infection risks and enhance implant success rates in the future.

18.
Dent J (Basel) ; 12(7)2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-39056980

RESUMO

This clinical report presents a technique to reconstruct extensively resected mandibles using a combination of autologous bone grafts and additive manufacturing techniques. Mandibular defects, often arising from trauma, tumors, or congenital anomalies, can severely impact both function and aesthetics. Conventional reconstruction methods have their limitations, often resulting in suboptimal outcomes. In these reports, we detail clinical cases where patients with different mandibular defects underwent reconstructive surgery. In each instance, autologous grafts were harvested to ensure the restoration of native bone tissue, while advanced virtual planning techniques were employed for precise graft design and dental implant placement. The patients experienced substantial improvements in masticatory function, speech, and facial aesthetics. Utilizing autologous grafts minimized the risk of rejection and complications associated with foreign materials. The integration of virtual planning precision allowed customized solutions, reducing surgical duration and optimizing implant positioning. These 2 cases underscores the potential of combining autologous grafts with virtual planning precision and dental implants produced by additive manufacturing for mandible reconstruction.

19.
Dent J (Basel) ; 12(7)2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-39056981

RESUMO

The importance of augmenting the peri-implant soft- and hard-tissue architecture is now widely accepted. However, while most contemporary research supports this premise, clinicians are encountering peri-implant soft tissue defects with increasing frequency, which they are therefore required to reconstruct. These complications can result from the difficulty of establishing an appropriate diagnosis and treatment plan or from suboptimal clinical situations (implant malposition, insufficient vestibular alveolar bone thickness or inadequate mucosal thickness). In this context, it is the peri-implant soft-tissue phenotype that most influences esthetic and health-related results in the short and long term. This article describes two clinical cases in which a modification of the apical access technique is presented that may be useful in clinical scenarios requiring large gains in mucosal thickness. Use of the modified bilaminar apical access with de-epithelialized free gingival graft technique showed promising results, with a significant increase in mucosal thickness and satisfactory outcomes in esthetics and peri-implant health.

20.
Dent J (Basel) ; 12(7)2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39057013

RESUMO

The objective of this study was to evaluate microbial leakage by means of genome counts, through the implant-abutment interface in dental implants with different Morse taper abutments. Fifty-six samples were prepared and divided in four groups: CMC TB (14 Cylindrical Implants-14 TiBase Abutments), CMX TB (14 Conical Implants-14 TiBase Abutments), CMX PU (14 Conical Implants-14 Universal Abutment) and CMX U (14 Tapered Implants-14 UCLA Abutments). Assemblies had their interface submerged in saliva as the contaminant. Samples were subjected either to thermomechanical cycling (2 × 106 mechanical cycles with frequency of 5 Hz and load of 120 N simultaneously with thermal cycles of 5-55 °C) or thermal cycling (5-55 °C). After cycling, the contents from the inner parts of assemblies were collected and analyzed using the Checkerboard DNA-DNA hybridization technique. Significant differences in the total genome counts were found after both thermomechanical or thermal cycling: CMX U > CMX PU > CMX TB > CMC TB. There were also significant differences in individual bacterial counts in each of the groups (p < 0.05). Irrespective of mechanical cycling, the type of abutment seems to influence not only the total microbial leakage through the interface, but also seems to significantly reflect differences considering individual target species.

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