International Journal of Implant Dentistry最新文献

Purpose: To assess the diagnostic performance of photon-counting computed tomography (PCCT) in the imaging of peri-implant bone structures and to compare it quantitatively and qualitatively to cone-beam computed tomography (CBCT).

Methods: Thirty titanium implants were placed in ten porcine mandibles. CBCT and PCCT scans were acquired and compared quantitatively regarding image noise and CT-values. Additionally bone thickness was compared to a gold standard at 60 standardized locations by one calibrated investigator in both modalities. Measurement accuracy was assessed by Bland-Altman analysis. Two experienced raters performed qualitative assessments of anatomic structures around the implant using a 5-point visibility scale. These included the bone-implant interface around the implant surface, the bone at the implant shoulder as well as the oral and vestibular bone lamella. Inter-rater agreement was assessed using ICC.

Results: Across all evaluated implants, CT-values in a soft-tissue region of interest adjacent to the implant increased by 11.7 ± 3.9% for CBCT acquisitions, whereas they decreased by 5.3 ± 1.3% for PCCT acquisitions. Similarly, image noise in the respective ROIs is increased by a factor of 63 ± 13% in case of CBCT acquisitions and only by 23 ± 5% in case of PCCT acquisitions. Bone thickness deviations were smaller for PCCT (mean ± SD: 0.06 ± 0.08 mm) than for CBCT (0.39 ± 0.34 mm). Qualitative assessments consistently favored PCCT (p < 0.05) with excellent inter-rater reliability (ICC > 0.75 ) in almost all categories.

Conclusions: PCCT enables superior visualization of peri-implant bone structures with fewer artifacts and improved diagnostic accuracy.

Despite widespread clinical success of dental implants, several fundamental questions remain unresolved: How does osseointegration-a biological phenomenon distinct from conventional bone healing-actually occur? Why does bone-implant contact never reach 100%? Why has there been minimal innovation in commercial implant surfaces over the past three decades? And why has the failure rate plateaued at around 8%? This review introduces the 3D Theory of Osseointegration, which conceptualizes implant integration as governed by three interdependent and dynamic determinants: material composition (Dimension 1), surface topography/roughness (Dimension 2), and time, which critically influences the physicochemical properties of implant surfaces (Dimension 3). For Dimension 1, the biocompatibility of various metals has been extensively studied, with commercially pure titanium and titanium alloys firmly established as the gold standard for dental implants. Dimension 3 underscores the long-overlooked impact of time-specifically, the biological aging of titanium surfaces caused by hydrocarbon accumulation and the loss of hydrophilicity-which significantly diminishes osteoconductivity. Importantly, recent studies have uncovered that this time-dependent degradation, once seen as an inevitable limitation, is in fact fully reversible. UV photofunctionalization restores surface hydrophilicity and removes hydrocarbon contaminants, revitalizing the bioactivity of titanium. This breakthrough not only resolves a long-standing barrier to optimal osseointegration but also establishes quantitative thresholds for key physicochemical parameters-such as carbon content and surface wettability. As a result, Dimensions 1 and 3-material and physicochemical properties-are approaching maturity in terms of optimization. In contrast, Dimension 2, surface topography, remains relatively underdeveloped despite decades of research and the clinical success of microrough surfaces. Now that UV photofunctionalization effectively mitigates biological aging and unlocks the full physicochemical potential of implant surfaces, the advancement of surface topography becomes the next critical frontier. This review critically examines each dimension, their interactions, and the limitations of current topographical design. It advocates for a shift from empirical to mechanism-driven engineering of implant surfaces and underscores the need for intentional synergy across all three dimensions. The 3D Theory of Osseointegration offers a structured framework to inform future implant design and research, aiming to better control and optimize the biological process of integration while acknowledging the complexities that still remain to be fully addressed.

Purpose: This prospective clinical pilot study aimed to evaluate oral health-related quality of life (OHRQoL) and both objective and subjective masticatory function following treatment with implant-supported overdentures on two reduced-diameter titanium-zirconium implants in the edentulous maxilla and mandible.

Methods: Ten edentulous patients received two implants each in the maxillary and mandibular canine regions. Implant-supported overdentures were placed after a conventional healing period. Patients completed a shortened form of the Oral Health Impact Profile (OHIP-G14) and rated their chewing ability on a visual analog scale (VAS) at baseline and after 6, 12, 24, and 36 months. A standardized masticatory function test assessed objective chewing function. Statistical analysis comprised descriptive analysis and changes or differences in means were analyzed using different tests (Wilcoxon signed rank test, Friedman test).

Results: Significant increases in subjective ability to eat various foods were noted after six months (P ≤.05). The mean total OHIP score decreased significantly from 33.2 at baseline to 4.7 at the 36-month follow-up. Objective masticatory efficacy showed significant improvement immediately after treatment (P =.005), with effects consistent over 36 months. At that time, six maxillary implants had been lost, while no mandibular implants had failed.

Conclusions: In this clinical pilot study, the rehabilitation of a completely edentulous maxilla and mandible with two implants and a removable overdenture significantly enhanced OHRQoL and both subjective and objective masticatory ability over an observation period of 36 months.

Objective: • To systematically determine the effectiveness of biphasic calcium phosphate (BCP) as bone substitute materials (BSM) compared to other BSMs for new bone formation in dental implant treatment through a network meta-analysis (NMA).

Materials and method: • Following PRISMA-NMA guidelines, randomized controlled trials (RCTs) on lateral sinus augmentation and dental implants comparing BCP with other BSMs for histomorphometric new bone formation were included. Studies were retrieved from MEDLINE, Cochrane, Scopus, and Embase (up to November 2024), with quality assessed via the Cochrane risk of bias 2 (RoB2.0) tool. Analysis included direct and network meta-analyses using a random-effects model, with SUCRA scores determining treatment rankings. The PROSPERO registration number was CRD42024607526.

Results: • Of 268 studies, 11 met criteria, covering 283 patients and 362 sinus augmentations using autografts (AB), allografts (AL), beta tricalcium phosphate (TCP), BCP, and xenografts (Xeno). NMA showed AB resulted in 12.33% more new bone formation than BCP (95% CI: 10.74, 13.93), with AL showing 5.14% more (95% CI: 3.33, 6.95). Xeno showed 4.14% less bone formation than BCP (95% CI: -6.38, -1.90). AB ranked highest for new bone formation, followed by AL, BCP, TCP, and Xeno. Residual graft material was highest in Xeno (6.21%; 95% CI: 2.81, 9.61).

Conclusion: • BCP demonstrated sufficient new bone formation, outperforming xenografts in both bone formation and residual graft material. While autografts and allografts exhibited superior bone regeneration, BCP remains an effective option for bone augmentation treatments.

Purpose: To evaluate the marginal and internal compatibility of computer-aided design and computer-aided manufacturing crowns produced via a digital workflow using an intraoral scanner, and to compare this digital-detection technique with the conventional fit test using silicone rubber (silicone-compatibility technique) on various abutments.

Methods: Implant bodies were placed in the maxillary right central incisor and mandibular right first molar of reference models. Digital scans were acquired using an intraoral scanner, and abutments were prepared. Twenty-four crowns with a cement space of 70 μm were fabricated from the digital file of the abutment. The crown's inner surface, abutment, and occlusal surface were scanned. The gaps between the crown and abutment were measured using stereoscopic image analysis software based on standard triangulated language data, and the accuracy of the fit was verified using silicone rubber.

Results: Significant differences (P < 0.05) were observed between the silicone-compatibility and digital-detection techniques for the maxillary central incisor at the incisal edge and the palatal lower region, and for the mandibular first molar at the occlusal surface and the center of lingual axis. The digital-detection technique yielded values closer to 70 μm for the cement space. The values measured using the silicone-compatibility technique exhibited greater variation than those measured using the digital-detection technique.

Conclusions: The novel digital-detection technique had superior or equivalent performance compared to the silicone-compatibility technique and could be beneficial for verifying crown fitness accuracy.

Purpose: This study aims to investigate the potential complication of implant displacement into the maxillary sinus, exploring its etiology and various management strategies, while proposing a systematic approach for clinicians to effectively address this evolving complication.

Materials and methods: This retrospective multi-center cohort study evaluated patients with dental implant migration into the maxillary sinus treated between 2010 and 2023 at two Israeli medical centers. Data included demographics, symptoms, clinical findings, and treatment modalities.

Results: 32 patients (mean age: 62.3 years) were analyzed, with a notable incidence of sinusitis and oroantral fistulas. 91% required surgical intervention, predominantly Functional Endoscopic Sinus Surgery (63%). The majority of displacements occurred during the implantation process, often correlating with clinical symptoms.

Conclusion: As shown in our study, displacement of implants into maxillary sinus, often leads to sinusitis and oroantral fistula. A proposed treatment algorithm emphasizes surgical intervention, particularly Functional Endoscopic Sinus Surgery, based on symptoms and clinical signs.

Purpose: This retrospective study aimed to evaluate the incidence of dehiscence following bone augmentation with patient-specific titanium meshes and to identify factors associated with its occurrence.

Material and methods: Patients who underwent bone grafting with patient-specific titanium mesh between December 2014 and October 2021 were included. The primary outcome was the occurrence of dehiscence. The occurrence of dehiscences was recorded during the following time phases, enabling the determination of whether dehiscences occur early (< 2 weeks), in the mid-term (2-9 weeks), or later in the healing phase (> 9 weeks).

Results: A total of 78 patients undergoing 85 titanium mesh augmentations were included, with a mean follow-up period of 1.2 years. Dehiscence occurred in 33 meshes (38.8%), with 51.5% of these events arising during the early healing phase. In no case was premature removal of the titanium mesh required due to dehiscence. A statistically significant association was observed between dehiscence and both smoking behavior (p < 0.001) and the anatomical location of the maxillary defect (p = 0.029). No significant associations were found between dehiscence and gender (p = 0.160), periodontitis (p = 0.512), gingival phenotype (p = 0.495), defect type (p = 0.490), augmented bone volume (p = 0.373), or incision type (p = 0.354). Logistic regression analysis further identified smoking (odds ratio: 7.07; 95% CI: 2.19-22.80) and maxillary defect alveolar (odds ratio: 11.86; 95% CI: 0.34-4.60) as significant predictors of dehiscence.

Conclusion: Dehiscence following customized titanium mesh augmentation was significantly associated with smoking and the location of the maxillary defect, underscoring the importance of early detection and timely intervention.

Purpose: The objective of this study was to evaluate the effect of flap suturing on the movement of graft materials during Guided Bone Regeneration (GBR) and to analyze the stability of moldable octacalcium phosphate (mOCP) depending on the type of graft material and membrane fixation method using Cone Beam Computed Tomography (CBCT).

Methods: A total of 60 standardized rectangular-shaped bone defects were created in the alveolar ridges of mandibles from 5-6-month-old pigs (20 defects per group), and implants (4.0 mm in diameter, 10.0 mm in height) were placed into each defect. The control group employed particle-type OCP and a collagen membrane, experimental group 1 utilized particle-type OCP and a collagen membrane with fixation pins, and experimental group 2 employed mOCP and a collagen membrane. CBCT analysis was performed to evaluate changes in horizontal thickness (HT) at the grafted sites.

Results: CBCT analysis revealed that the percentage reduction in HT at the implant shoulder level was significantly lower in experimental group 1 (16.7%) and experimental group 2 (16.3%) compared to the control group (31.5%), with no statistically significant difference observed between experimental groups 1 and 2.

Conclusion: The use of mOCP in guided bone regeneration demonstrated comparable volumetric stability to grafts utilizing collagen membranes fixed with titanium pins, suggesting its potential to simplify surgical procedures by eliminating the need for additional fixation devices.