Clinical implant dentistry and related research最新文献

Objective: To evaluate the efficacy of 3D-printed scaffolds that were osteoinductively functionalized with a bone morphogenetic protein 2 (BMP-2)-incorporated biomimetic calcium phosphate particles (BMP-2-inc. BpNcCaP)/hyaluronic acid (HA) composite gel in vertical bone augmentation in beagle dogs.

Materials and methods: Four Beagle dogs were used in this study. Three months after the extraction of 1st, 2nd, 3rd, and 4th premolars at both sides of the lower jaws of Beagle dogs, one or two critical-size vertical bone defects (4 mm vertical bone defect without buccal and lingual bone) on each side were surgically created. The defects were randomly subjected to the following groups: (1) Control (without bone-defect-filling materials); (2) 3D scaffold; (3) BMP2-inc. BpNcCaP/HA-functionalized 3D scaffold. Six weeks post-surgery, samples were harvested and subjected to micro-CT and histomorphometric analyses.

Results: The struts of the BMP2-inc. BpNcCaP/HA-func. 3D scaffold were covered by a thick layer of cemented irregular particles with an average pore size at 327 ± 27 μm. The BpNcCaP/HA-func. 3D scaffold group bore significantly higher bone volume, bone volume fraction, trabecular number, trabecular thickness, bone mineral density, connectivity density, and bone volumes in three directions (mesiodistal, buccolingual, and apicocoronal) when compared with the groups of Control and 3D scaffold. Moreover, the BMP2-inc. BpNcCaP/HA-func. 3D scaffold group bore significantly lower trabecular separation and exhibited significantly higher bone-to-scaffold contact percentage and newly formed bone area percentage within pores in comparison with 3D scaffold.

Conclusions: BMP2-inc. BpNcCaP/HA-func. 3D scaffold dramatically enhanced vertical alveolar bone augmentation, which suggests a promising application potential of BMP2-inc. BpNcCaP/HA-func. 3D scaffold in dental clinic.

Background: Sinus floor elevation is one of the predictable techniques for augmentation of vertically deficient posterior maxillary alveolar ridges. Several biomaterials were reported to be successful for sinus augmentation, including xenografts and hydroxyapatite. The aim of this study was to compare the quality and quantity of generated bone using xenografts versus nanohydroxyapatite in sinus augmentation.

Methodology: Twenty-four patients/sinuses were randomly assigned into two groups; in the control group, patients underwent sinus floor elevation and augmentation using deproteinized bovine bone (DBB), whereas in the study group, the sinus was augmented using nanohydroxy-apatite bone (NHA). For each patient, the amount of bone height was assessed preoperatively, immediately postoperatively, and 6 months postoperatively. Furthermore, the quality of the newly formed bone was assessed via histological and histomorphometric analyses after 6 months postoperatively.

Results: Both biomaterials showed a good level of consolidation. In the study group, the mean bone height after 6 months was 11.72 ± 1.24 compared to 12.01 ± 1.16 mm in the control group which was not statistically significant (p > 0.05). The mean bone area percent of newly formed bone was 29.84% ± 6.7% for NHA group and 34.73 ± 7.9 for DBB group. Moreover, the mean percent of residual grafting material was 32.43% ± 11.53% for NHA group compared to 30.43% ± 8.27% for DBB group. Histologically, there was no significant difference between both groups regarding different parameters (p > 0.05).

Conclusion: The two-stage sinus floor augmentation using NHA and DBB revealed no statistically significant difference regarding both the quality and the quantity of the regenerated bone. Studies with larger samples and longer follow up are recommended.

Trial registration: ClinicalTrials.gov identifier: NCT03184857.

Aim: Technology improvement and a better understanding of sinus anatomy and wound healing in the past decade have allowed the development of minimally invasive surgical techniques. This systematic review focused on identifying and describing these techniques for vertical and lateral sinus augmentation (VSA and LSA).

Materials and methods: Electronic and hand search were conducted to screen the literature published from January 2003 to May 2024. The selected studies had to include detailed techniques for minimally invasive SA. Data extraction included the study types, sample size, technique/instrument details, and outcome measurements.

Results: A total of 36 articles (27 VSA, 8 LSA with an additional 1 article included both procedures) with 2732 sinus augmentation met the inclusion criteria. Minimally invasive VSA includes the use of modified rotary instruments with stopper, balloon, hydraulic pressure, digital planning, endoscope, and operating microscope. These techniques aim for conservative flap reflection, precise sinus window preparation, and/or controlled sinus membrane elevation. Most of the selected studies (n = 15) did not report the incidence of sinus membrane perforation.

Conclusion: Within the limitations of this review, minimally invasive VSA and LSA achieved sufficient sinus augmentation and implant success with the potential advantages of reduced surgical complications and morbidity. Comparative studies with defined outcomes are encouraged to further validate these useful minimally invasive techniques for SA.

Objectives: The objective of this study is to investigate the effect of collagen matrix with polydeoxyribonucleotide (PDRN) at two concentrations on keratinized tissue (KT) regeneration for buccally positioned implants in canines.

Methods: Four implants were placed in the edentulous mandible of five dogs simultaneously with KT removal. The implants were positioned buccally with respect to the ridge crest. After 2 months, KT augmentation was performed applying the following treatment modalities:(1) free gingival graft (FGG), (2) xenogeneic collagen matrix (XCM), (3) XCM loaded with 2 mg/mL PDRN (PDRN2), and (4) XCM loaded with 4 mg/mL PDRN (PDRN4). All animals were sacrificed 3 months later. Outcomes included clinical (KT height) and histomorphometric measurements (KT height/length, level of the mucosa, mucosal thickness, supracrestal soft tissue height).

Results: Clinical and histomorphometric KT formation at 3 months was greatest in groups with FGG (4.70 ± 1.00/3.94 ± 0.93 mm) and PDRN2 (4.85 ± 1.43/3.95 ± 0.87 mm). Group PDRN2 (1.87 ± 1.50 mm) showed a higher marginal mucosal level with respect to the implant platform compared to other groups (range: 0.57 ± 0.97-0.69 ± 1.14 mm). All groups presented a soft tissue thickness of < 2 mm on the buccal aspect of the implants.

Conclusions: Based on the limitations of this pilot preclinical study, XCM with 2 mg/mL of PDRN demonstrated a potential for KT augmentation.

Objective: The study evaluates three biologically active substances with known bone-inductive potential on previously decontaminated titanium (Ti) discs.

Material and methods: Rough and smooth Ti surfaces were contaminated with a multispecies biofilm and cleaned with a chitosan brush. Discs were treated either with injectable-platelet-rich fibrin (i-PRF), advanced platelet-rich fibrin (A-PRF+), or enamel matrix derivatives (EMDs) before osteoblast seeding.

Results: Biocompatibility, adhesion, migration, and gene expression of runt-related transcription factor 2 (RUNX2), collagen Type I Alpha 2 (COL1a2), alkaline phosphatase (ALP), osteocalcin (OC), and osteonectin (ON) were performed. All the tested biologic agents similarly increased cell viability. Specifically, osteoblasts seeded over i-PRF and EMD-treated surfaces showed improvement in adhesion and migration and significantly increased ALP, OC, ON, RUNX-2, and COL1a2 mRNA levels up to 2.8 fold (p < 0.05) with no differences between Ti surfaces.

Conclusions: i-PRF and EMD possess beneficial bioactive properties that enhance tissue healing and promote regeneration on thoroughly sterilized surfaces. Biologically active materials may hold the potential to influence the process of implant re-osseointegration, which warrants more research since sterilization of the affected surfaces under clinical conditions is still not reliably possible and remains one of the greatest challenges.

Objective: Soft tissue seal around implants ensures stable osseointegration and a long-term survival of dental implants. Different surface modification and decontamination for implant abutments were endorsed in order to improve peri-implant soft tissue healing, such as laser, plasma spray, acid etching, and steaming. The aim of this study was to evaluate the response of peri-implant soft tissue to titanium abutments treated with Erbium-doped: Yttrium-Aluminum-Garnet (Er:YAG) laser versus plasma spray.

Methods: Twenty-four patients who required implant placement in the maxillary arch participated in this study. Patients were divided into three groups, abutments treated with Er:YAG laser versus cold plasma spray and untreated abutments. Fourteen days following the implant abutment insertion, soft tissue peri-implant biopsies were taken for histological, histochemical, and immunohistochemical evaluation. Scanning electron microscopy was done for the abutments; plaque index (PI) and gingival index (GI) were assessed 14 days and 3 months following final restoration.

Results: Regarding the histological results, the least mean inflammatory cell count was in the plasma group (174.09 ± 40.67), followed by the laser group (654.27 ± 85.95) and the control group (852.00 ± 117.98), with statistically significant differences between them. The mean area fraction of collagen fibers showed the highest value in the plasma group (9.73 ± 1.91), followed by the laser group (3.25 ± 0.49), while the lowest value was found in the control group (1.17 ± 0.51). The immunohistochemical expression of E-cadherin was significantly higher and uniformly distributed in the plasma group (42.4 ± 11.2%) followed by the laser group (15.4 ± 4.07%) and the control group (6.8 ± 1.7%). SEM analysis of healing abutments showed fibroblast-like cells, which were more developed with dense fibers in the plasma group; laser group fibers showed fewer and more delicate fibers than the plasma group, while no fibers were detected in the control group.

Conclusion: Within the limitations of this feasibility study, the present data concluded that plasma spray and Erbium: YAG laser can be used for abutment surface treatment to achieve better peri-implant soft tissue healing. Clinically and histologically, plasma spray showed a better effect on the peri-implant soft tissues by reducing the inflammatory reaction, promoting collagen fiber formation, higher fibroblast-like cell attachment, and upregulating E-cadherin expression than Erbium: YAG laser and control groups.

Background: The learning curve effect of dynamic computer-assisted implant surgery (D-CAIS) was observed among inexperienced novice surgeons. The learning curves can provide valuable information for novice surgeons and valid comparisons between new and conventional techniques. Recently, robotic computer-assisted implant surgery (R-CAIS) has shown promise as a novel dental implant surgical technique for both partially and edentulous patients. However, its learning curve remains unknown.

Purpose: The aim of this study was to explore the learning curve of dental implant placement surgery with a task-autonomous robotic system among young dentists with different specialties.

Methods and materials: Four young dentists (mean age: 25.3 ± 1.5 years at the beginning of their first attempt) with equal representation of males and females and with different specialties participated in this study. None of the participants had prior experience in R-CAIS. Each operator placed eight implants over eight attempts using a semi-active task-autonomous robotic system. Among the eight implants, four were straight lateral incisor implants, and four were 30°-tilted premolar implants. The implants were placed in each dental quadrant of the maxillary and mandibular jaw modules. The operation time was recorded. Coronal, apical, and angular deviations between the planned and actual sites of implant placement were measured by merging preoperative and postoperative cone-beam computed tomography (CBCT) scans. The data were analyzed with repeated-measures ANOVA (α = 0.05).

Results: The mean time for implant placement was associated with the number of attempts (p < 0.01). The time taken for the second attempt was significantly shorter than that of the first attempt (33.26 vs. 30.47 min; p < 0.001) then it plateaued. Three-dimensional (3D) angular (p = 0.31), coronal deviation (p = 0.26), and apical deviation (p = 0.06) did not differ significantly among attempts. The mean values and standard deviations of 3D coronal deviation, 3D apical deviation, and 3D angular deviation were 0.71 ± 0.31 mm, 0.72 ± 0.30 mm, and 0.94 ± 0.58°, respectively. Neither the position of the jaw (p > 0.59) nor the tilt angle of the implant (straight or 30°-tilted, p > 0.85) was related to implant placement accuracy.

Conclusions: Dentists quickly learned the basic workflow of R-CAIS and thus facilitated the clinicians in the mastery of implant placement on edentulous jaw modules, leading to a comparable operating speed and high precision. Moreover, the accuracy of placement of straight and tilted implants in both the maxilla and mandible with R-CAIS was satisfactory.

Objectives: To assess the costs and efforts of maintenance therapy following implant treatment with fixed restoration over an observation period of 10 years.

Material and methods: This randomized controlled clinical trial included 64 patients who were randomly assigned to receive one of two implant systems (AST or STM) and fixed restoration. Patients were included in a regular maintenance program and were examined at loading, 1, 3, 5, 8, and 10 years. Outcome measures included technical and biological complications, time, efforts, and costs to resolve them.

Results: A total of 97 implants were placed in 64 patients (AST: 54, STM: 43). Patient recall rates at 5 and 10 years were 89% and 67%. In general, technical complications were resolved within one to two appointments (mean = 1.5), and biological complications required a mean of 1.3 appointments. The overall regular maintenance time for the period of 10 years amounted to 77 min per year. Technical complications occurred in 39.5% of the patients, with screw-loosening being the most common one (43.4% of all complications). The most time-consuming technical complication was abutment fracture (94 min ± 68), followed by screw fracture (84 min ± 38). The prevalence of peri-implant mucositis on the patient level was 30.2%, and it was 9.3% for peri-implantitis. The average annual maintenance costs amounted to 9% of the initial cost of the implant treatment over the period of 10 years.

Conclusions: Additional regular maintenance costs and costs due to the treatment of potential complications have to be taken into consideration when placing dental implants. The majority of technical complications could be resolved within one appointment, whereas the time needed to treat biological complications varied between one and three appointments for peri-implantitis.

Objectives: To compare patients' satisfaction and oral health-related quality of life (OHRQoL) in edentulous patients treated by All-on-4 and All-on-6 implant-supported fixed prostheses rehabilitation over 3-7 years.

Methods: All patients (n = 125) were divided into short-term (3-5 years, n = 71) and long-term (5-7 years, n = 54) follow-up groups. Patients' satisfaction was examined in a cross-sectional survey. OHRQoL and psychological impact were evaluated using the Oral Health Impact Profile (OHIP). Comparison of All-on-4 and All-on-6, including OHIP values, satisfaction scores, treatment duration and complications, were analyzed using the Chi-square test and the Mann-Whitney U test. Potential influence of patient-related factors on patient-reported outcome measures (PROMs) were analyzed via the Mann-Whitney U test, the Kruskal-Wallis test and multiple regression analyses. Power calculation was conducted in R Studio.

Results: Both All-on-4 and All-on-6 follow-up groups showed high scores in total satisfaction and PROMs, including chewing comfort, aesthetics, cleanability, and stability, with no significant difference (p > 0.05). Meanwhile, no significant differences were observed in the OHIP scores between two groups in both follow-up durations (p > 0.05). However, in patients with 3-5 years follow-up, All-on-4 group had significantly lower phonetic satisfaction scores than All-on-6 group (p < 0.05). Additionally, during both follow-up periods, All-on-4 patients exhibited notably superior psychological effect in contrast to All-on-6 patients (p < 0.05).

Conclusions: Edentulous patients treated by four or six implant-supported fixed prostheses showed same high satisfaction in oral health-related quality of life in both 3-5 years and 5-7 years follow-ups.