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oe1(光电查) - 科学论文

9 条数据
?? 中文(中国)
  • Antimicrobial efficacy of photodynamic therapy on dental implant surfaces: A systematic review of in vitro studies

    摘要: Background: To systematically review the literature regarding the antimicrobial effects of photodynamic therapy (PDT) on the multi-bacterial species and the possible surface alterations of the dental implants as a result of PDT. Methods: The addressed focused question was: “Does PDT show antimicrobial efficacy against multi-bacterial species colonization and result in surface alteration on dental implants?” Electronic databases including MEDLINE and EMBASE up to and including December 2018 were searched. Results: Seven studies were included. Two studies used a total of 110 titanium dental implants, while 1 study included a total of 72 zirconia dental implants. Three studies investigated the antimicrobial PDT effects on titanium discs, while 1 study used titanium plates with germanium prisms. All in-vitro studies used diode laser. Energy fluence was reported only in 2 studies. Power output and density were 100 milliwatts (mW) and 150 mW cm-2, respectively. All in-vitro studies reported the multibacterial species outcomes after the application of antimicrobial PDT. All studies showed a significant reduction in the bacterial load. Only two studies reported the outcomes of microstructural changes on the titanium surface, in which both studies did not report any significant alterations on the titanium implants or discs with the application of PDT. Conclusion: This systematic review demonstrated significant reduction in the bacterial load but inconclusive findings regarding structural alterations on the titanium surface with the use of PDT. The results of this review should be considered preliminary and further in-vitro studies with standardized laser parameters are needed to obtain strong conclusions.

    关键词: systematic review,titanium surface,dental implants,photodynamic therapy,bacterial load

    更新于2025-09-23 15:22:29

  • Clinical and radiographics results at 3 years of RCT with split-mouth design of submerged vs. nonsubmerged single laser-microgrooved implants in posterior areas

    摘要: Aim: To evaluate and compare radiographic crestal bone loss (CBL) and soft tissue parameters around submerged/two-stage and nonsubmerged/one-stage single implants with the same endosseous portion (body design and surface, thread design and distance) and identical intramucosal laser-microgrooved surface, after 3 years of loading. Materials and methods: Twenty submerged/two-stage implants and 20 nonsubmerged/one-stage implants were placed randomly with a split-mouth design in the posterior areas of 20 partially edentulous patients. Radiographic and clinical examinations were carried out at the implant placement, at the delivery of prosthetic restorations, and at each year of the follow-up period. Plaque index (PI), probing depth (PD), bleeding on probing (BOP), and gingival recession (REC) were recorded. Radiographic crestal bone levels were assessed at the mesial and distal aspect of the implant sites. In addition, the influence of the vertical keratinized tissue thickness (KTT) on CBL was investigated. Results: At the delivery of prosthetic restorations, a statistically significant difference (P = 0.013) was found in radiographic mean CBL between submerged and nonsubmerged implants (0.15 ± 0.05 mm vs. 0.11 ± 0.04 mm). At the end of the follow-up period, no statistical difference (P = 0.741) was found in the mean CBL between submerged and nonsubmerged implants (0.27 ± 04 mm vs. 0.26 ± 0.5 mm). The changes in the soft tissues including PI, PD, BOP, and REC had no significant differences in either group. Moreover, KTT did not show a statistical correlation with CBL. Conclusions: After 3 years of loading, no statistical difference was noted in CBL and soft tissue conditions between single submerged two-stage and nonsubmerged one-stage laser-microgrooved implants.

    关键词: Submerged two-stage,Nonsubmerged one-stage,Dental implants,Marginal bone loss

    更新于2025-09-23 15:21:01

  • Evaluation of adjunctive efficacy of diode laser in the treatment of peri-implant mucositis: a randomized clinical trial

    摘要: Peri-implant disease may affect survival of dental implants. The aim of the study is to analyze the effectiveness of diode laser as a supportive modality to the non-surgical conventional treatment of peri-implant mucositis (PiM) and initial peri-implantitis (PI). Twenty-three patients with single implants suffering from PiM or initial PI were selected and randomly divided into two groups; control group (CG) received non-surgical conventional treatment, and test group (TG) received non-surgical conventional treatment and diode laser application with wavelength of 980 nm. Probing pocket depth (PPD) and bleeding on probing (BOP) were recorded at baseline (T0) and at 3 months follow-up (T1). The average of PPD value for TG was 4.04 ± 0.54 mm at T0 and it was 2.98 ± 0.70 mm at T1. In the CG, PPD average was 3.8 ± 1.24 mm at T0 and was 3.54 ± 0.35 mm at T1. In TG, the BOP was positive in 44 sites at T0 and in 6 sites at T1. In CG, the BOP was positively observed in 52 sites at T0 and in 28 sites at T1. The 980-nm diode laser may be considered an adjunct to the conventional non-surgical treatments of PiM and initial PI.

    关键词: Mucositis,Debridement,Dental implants,Peri-implant,Diode laser

    更新于2025-09-23 15:19:57

  • Influence of lowa??level laser therapy on implant stability in implants placed in fresh extraction sockets: A randomized clinical trial

    摘要: Background: Low-level laser therapy (LLLT) has been suggested to improve primary stability at the early stages of osseointegration in animal models. However, there is still scarce evidence about its influence on implant stability in humans. Purpose: To assess the influence of LLLT on implant stability in implants placed in fresh extraction sockets. Material and methods: A randomized controlled trial was designed according to the SPIRIT guidelines and is reported following the CONSORT. Patients were randomly allocated according to control or LLLT groups. LLLT consisted in the application of GaAlAs laser (808 nm, avg. power density: 50 mW, circular spot diameter and area: 0.71 cm/0.4cm2) applied in six points in contact mode with peri-implant soft tissue (1.23 minutes in each point of application; dose per point 11 J) before bone perforation and after suturing. The total dose resulted in 66 J per application moment. This LLLT protocol was applied only in the dental implant placement session. Implant stability was by ISQ at implant placement (T0) and the abutment selection (Ta). Digital radiographs for T0 and Ta were used to assess the distance between the implant platform and alveolar bone crest, in millimeters. T-test and Shapiro-Wilk test were used to analyze data between groups using the implant as a unit of analysis. Results: Fifty implants were placed in 44 patients. The insertion torque ranged from 15 to 60 N.cm (mean 35.64 ± 13.34). Two implants of the LLLT and one of the control groups were lost to follow-up and one implant of the control group failed to osseointegrate (4.3%). ISQ at T0 ranged from 17 to 79 (mean 59.33 ± 13.05) and from 40 to 89 (mean 66.46 SD ± 11.56) at Ta. No differences were observed when comparing the groups with ISQ difference (P = .433) or radiographical peri-implant alterations (P = .261). Conclusions: LLLT did not influence implant stability in implants placed in fresh extraction sockets when assessed at healing abutment installation.

    关键词: osseointegration,gallium aluminum arsenide lasers,dental implants,controlled clinical trial

    更新于2025-09-23 15:19:57

  • Ultrashort Pulsed Laser Surface Patterning of Titanium to Improve Osseointegration of Dental Implants

    摘要: Ultrashort pulsed direct laser interference patterning (DLIP) is used to generate hierarchical line-like patterns on titanium surfaces to control cell adhesion and spreading on dental implants, thereby improving osseointegration. The DLIP structures have spatial periods of 3, 5, 10, and 17 μm. They are produced using a laser source with a pulse duration of 10 ps and cumulated energy densities between 0.1 and 78.9 J cm?2. Laser-induced periodic surface structures (LIPSS) and submicron features are obtained on the treated samples. The DLIP treatment leads to the development of a thick titanium oxide layer, which is imaged and quantified using time-of-flight secondary ion mass spectrometry (ToF-SIMS). Several days (30–56) after the laser treatment, specimens with larger spatial periods are hydrophilic, whereas samples with spatial periods of 3 μm are hydrophobic. Seeded human osteoblasts on the laser-structured samples show 2.5 times higher cell numbers after 7 days in vitro culture compared with osteoblasts on a grit-blasted and etched reference sample. Finally, cell adhesion to a structured 3D dental implant is demonstrated.

    关键词: dental implants,surface functionalization,direct laser interference patterning,osseointegration,titanium

    更新于2025-09-19 17:13:59

  • Computer-designed selective laser sintering surgical guide and immediate loading dental implants with definitive prosthesis in edentulous patient: A preliminary method

    摘要: Objective: The aim of this study was to analyze a preliminary method of immediately loading dental implants and a definitive prosthesis based on the computer?aided design/computer?aided manufacturing systems, after 2 years of clinical follow?up. Materials and Methods: The study comprised one patient in good general health with edentulous maxilla. Cone beam computer tomography (CBCT) was performed using a radiographic template. The surgical plan was made using the digital imaging and communications in medicine protocol with ImplantViewer (version 1.9, Anne Solutions, Sao Paulo, SP, Brazil), the surgical planning software. These data were used to produce a selective laser sintering surgical template. A maxilla prototype was used to guide the prosthesis technician in producing the prosthesis. Eight dental implants and a definitive prosthesis were installed on the same day. A post?operative CBCT image was fused with the image of the surgical planning to calculate the deviation between the planned and the placed implants positions. Patient was followed for 2 years. Results: On average, the match between the planned and placed angular deviation was within 6.0 ± 3.4° and the difference in coronal deviation was 0.7 ± 0.3 mm. At the end of the follow?up, neither the implant nor the prosthesis was lost. Conclusions: Considering the limited samples number, it was possible to install the dental implants and a definitive prosthesis on the same day with success.

    关键词: immediate loading dental implant,Computer-assisted surgery,dental implants

    更新于2025-09-11 14:15:04

  • Femtosecond laser microstructuring of alumina toughened zirconia for surface functionalization of dental implants

    摘要: The continuous need for high-performance implants that can withstand mechanical loads while promoting implant integration into bone has focused recent research on the surface modification of hard ceramics. Their properties of biocompatibility, high mechanical and fatigue resistance and aesthetic color have contributed to its successful applications in dentistry. Alumina toughened Zirconia (ATZ) has been gaining attention as a material for dental implants applications due to its advanced mechanical properties and minimal degradation at body temperature. Still, in order to improve tissue response to this bioinert material, additional modifications are desirable. Improving the surface functionality of this ceramic could lead to enhanced implant-tissue interaction and subsequently, a successful implant integration. In this work, microtopographies were developed on the surface of Alumina toughened Zirconia using an ultrafast laser methodology, aiming at improving the cellular response to this ceramic. Microscale grooves and grid-like geometries were produced on ATZ ceramics by femtosecond laser ablation, with a pulse width of 150 fs, wavelength of 800 nm and repetition rate of 1 kHz. The variation of surface topography, roughness, chemistry and wettability with different laser processing parameters was examined. Cell-surface interactions were evaluated for 7 days on both microstructured surfaces and a non-treated control with pre-osteoblasts, MC3T3-E1 cells. Both surface topographies showed to improve cell response, with increased metabolic activity when compared to the untreated control and modulating cell morphology up to 7 days. The obtained results suggest that femtosecond laser texturing may be a suitable non-contact methodology for creating tunable micro-scale surface topography on ATZ ceramics to enhance the biological response.

    关键词: Femtosecond laser microtexturing,Dental implants,Hard ceramics,Alumina toughened zirconia,Surface topography,Biological response

    更新于2025-09-11 14:15:04

  • Evaluation of linear measurements of implant sites based on head orientation during acquisition: An ex vivo study using cone-beam computed tomography

    摘要: Purpose: This study evaluated the effect of various head orientations during cone-beam computed tomography (CBCT) image acquisition on linear measurements of potential implant sites. Materials and Methods: Six dry human skulls with a total of 28 implant sites were evaluated for seven different head orientations. The scans were acquired using a Hitachi CB-MercuRay CBCT machine. The scanned volumes were reconstructed. Horizontal and vertical measurements were made and were compared to measurements made after simulating the head position to corrected head angulations. Data was analyzed using a two-way ANOVA test. results: Statistical analysis revealed a significant interaction between the mean errors in vertical measurements with a marked difference observed at the extension head position (P<0.05). Statistical analysis failed to yield any significant interaction between the mean errors in horizontal measurements at various head positions. conclusion: Head orientation could significantly affect the vertical measurements in CBCT scans. The main head position influencing the measurements is extension. (Imaging Sci Dent 2015; 45: 73-80)

    关键词: Dental Implants,Dimensional Measurement Accuracy,Patient Positioning,Cone-Beam Computed Tomography

    更新于2025-09-10 09:29:36

  • Quantification of image artifacts from navigation markers in dynamic guided implant surgery and the effect on registration performance in different clinical scenarios

    摘要: Purpose: Different navigation markers in dynamic guided implant surgery could cause different degrees of artifacts, which would affect the accuracy and efficiency of the implant navigation system. This study aimed to quantify artifacts caused by navigation markers made of different materials and to evaluate their effects on registration accuracy under various oral conditions. Materials and Methods: Four U-shaped tubes with different navigation markers (440c stainless steel, silicon nitride, zirconium oxide, and aluminium oxide) were produced by three-dimensional printing. Four kinds of maxillary plaster models were prepared to stimulate four tooth crown conditions. U-shaped tubes combined with different tooth models were scanned using cone beam computed tomography (CBCT). The size of artifacts from different navigation markers and registration rate were measured. Abrasion performance of navigation markers was evaluated by scanning electron microscopy (SEM) images. Results: Aluminium oxide navigation markers showed the fewest artifacts. Silicon nitride markers caused fewer artifacts than zirconium oxide and 440c stainless steel ones (P < .05) and had the best registration performance under all tooth crown conditions with the lowest volume of abrasion. Registration data suggested aluminium oxide worked badly under artificial crown and natural tooth conditions for its lower radiopacity, and zirconium oxide worked undesirably in edentulous conditions. 440c stainless steel was worst in all dental conditions. Conclusion: Navigation markers made of silicon nitride have the best overall performance and perform the best in registration under all circumstances owing to less artifact generation, better radiopacity, and desirable abrasion resistance. Silicon nitride can be regarded as an ideal material, including but not limited to oral implant navigator-guided surgery.

    关键词: Dental implants,Navigation marker,Cone-Beam Computed Tomography,Artefacts,Dynamic guided,Registration

    更新于2025-09-09 09:28:46