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Bioengineering (Basel, Switzerland) Jun 2024While technological advances have made implants a good treatment option with a good long-term prognosis, peri-implantitis, which results in alveolar bone resorption...
While technological advances have made implants a good treatment option with a good long-term prognosis, peri-implantitis, which results in alveolar bone resorption around implants, has been observed in some cases. Micromotion at the implant abutment connection can cause peri-implantitis. However, the temporal progression of micromotion upon loading remains unclear. Therefore, we aimed to longitudinally measure micromotion upon loading application on an implant. Implants with Morse-tapered connections were prepared. Custom titanium abutments were fabricated and tightened onto implant bodies at 35 N. A 100 N vertical load was applied for 200,000 cycles. Micromotion was measured when the load was applied, as was the total implant length and removal torque before and after loading. The micromotion was measured from the position data of the jig of the testing machine during loading. The average removal torque was 30.67 N after 10 min of tightening and 27.95 N after loading, indicating a decrease due to loading. The implant length reduced by 3.6 μm under the load. The average micromotion was 0.018 mm at 2 cycles, 0.016 mm at 100,000 cycles, and 0.0157 mm at 200,000 cycles, indicating implant length reduction under the load but not reaching 0. The micromotion between the implant and abutment under a cyclic load decreased over time but did not completely cease. These results highlight the relationship between micromotion and loading, underscoring the importance of careful monitoring and management to mitigate potential complications, such as peri-implantitis, and ensure optimal performance and durability of the implant.
PubMed: 38927818
DOI: 10.3390/bioengineering11060582 -
Bioengineering (Basel, Switzerland) Jun 2024Over time, numerous surgical procedures and biomaterials have been proposed for the reconstruction of post-extraction bone defects, each with their advantages and...
BACKGROUND
Over time, numerous surgical procedures and biomaterials have been proposed for the reconstruction of post-extraction bone defects, each with their advantages and disadvantages. The main objective of this study was to evaluate dimensional changes in the alveolar bone 3 months after tooth extraction, before implant planning, comparing alveolar ridge preservation (ARP) with spontaneous healing.
METHODS
A total of 84 patients with non-restorable molars were included in the study. Forty-two patients received ARP with advanced platelet-rich fibrin (A-PRF) and spontaneous healing was evaluated in these patients. Cone beam computed tomography (CBCT) analysis performed before and after surgical intervention was used to determine the changes in vertical and horizontal bone dimensions produced after tooth extraction.
RESULTS
CBCT measurements showed reduction in both vertical and horizontal alveolar bone size in both groups. For the study group, the alveolar parameters (height, width) were higher compared to the control group. The percentage variations between dimensional differences from the two groups were 38.58% for height, and for width were 36.88% at 0 mm, 35.56% at 3 mm, 36.61% at 5 mm, and 38.73% at 7 mm. The differences were statistically significant ( ˂ 0.0005).
CONCLUSIONS
The results obtained after ARP with A-PRF showed a reduced loss of bone volume compared to spontaneous healing.
PubMed: 38927802
DOI: 10.3390/bioengineering11060566 -
Bioengineering (Basel, Switzerland) May 2024Rectangular Block Implant (RBIs) were manufactured, using computer-aided-design lathe turning, surface roughened with grit blasting and gamma irradiated. Implants were...
Rectangular Block Implant (RBIs) were manufactured, using computer-aided-design lathe turning, surface roughened with grit blasting and gamma irradiated. Implants were surgically placed into the resorbed edentulous mandibular ridges of both greyhound dogs (ex vivo and in vivo) and humans; the pooled total was 17 placements. The aim was to achieve mechanical stability and full implant submergence without damage to the mandibular canal and without bone fracture: fulfilment of all of these criteria was deemed to be a successful surgical outcome. Rectangular osteotomy sites were prepared with piezo surgical instrumentation. Sixteen implants were fully submerged and achieved good primary stability without bone fracture and without evidence of impingement of the mandibular canal. One implant placement was deemed a failure due to bone fracture: the event of a random successful outcome was rejected ( < 0.01 confidence, binomial analysis). Technique of placement yielded excellent mechanical retention: key biomechanical factors that emerged in this process included under preparation of the osteotomy site with the use of specifically designed trial-fit gauges, the viscoelastic property of the peri-implant bone, the flat faces and cornered edges of the block surfaces which enhance stress distribution and mechanical retention, respectively. It was concluded that the surgical protocol for the RBI placement in the resorbed alveolus is a predictable clinical procedure tailored to its specific, unique biomechanical profile.
PubMed: 38927768
DOI: 10.3390/bioengineering11060532 -
Antibiotics (Basel, Switzerland) Jun 2024This comprehensive review aimed (1) to characterize the sub- and supragingival microbiome in patients with biofilm-induced gingivitis (including experimental... (Review)
Review
This comprehensive review aimed (1) to characterize the sub- and supragingival microbiome in patients with biofilm-induced gingivitis (including experimental gingivitis), (2) to assess its stability and evolution over time, and (3) to assess the impact of biofilm control measures on this stability. An electronic search of the MEDLINE/PubMed database until December 2023 was conducted. NCBI Taxonomy, eHOMD 16S rRNA Reference Sequence, and Tree Version 15.23 databases were used to standardize taxonomic nomenclature. Out of 89 papers initially retrieved, 14 studies were finally included: 11 using experimental gingivitis as a model and three randomized clinical trials evaluating the impact of biofilm control measures. Among them, five characterized the subgingival microbiome, nine the supragingival microbiome, and one both the sub- and supragingival microbiome. In addition, five studies evaluated the effect of toothpaste, and four studies evaluated the effect of mouth rinses. The diversity and structure of the microbiome differed significantly between patients with periodontal health and those with biofilm-induced gingivitis (including experimental gingivitis). Those differences were not reversed through conventional oral hygiene measures. Specific antiseptic agents, especially if delivered as mouth rinses, may have an impact on the supra- and subgingival microbiome in gingivitis.
PubMed: 38927237
DOI: 10.3390/antibiotics13060571 -
Biomolecules Jun 2024Osteoblastic responses play a crucial role in the success of oral implants. Enhanced proliferation of osteoblast cells is associated with reduced cell mortality and an... (Comparative Study)
Comparative Study
INTRODUCTION
Osteoblastic responses play a crucial role in the success of oral implants. Enhanced proliferation of osteoblast cells is associated with reduced cell mortality and an increase in bone regeneration. This study aims to evaluate the osteoblastic responses following oral implantation.
MATERIALS AND METHODS
Osteoblast stem cells were harvested and subsequently cultivated using cell culture techniques. The osteoblastic phenotype of the extracted cells was confirmed by examining the extracellular matrix. Cell morphogenesis on functionalized biomaterial surfaces was assessed through indirect immunofluorescence staining. The cellular response was investigated in the presence of two types of implant materials: titanium (Ti) and alumina-toughened zirconia (ATZ). Cell viability and apoptosis were quantitatively assessed using MTT assays and flow cytometry, respectively.
RESULTS
The survival of osteoblastic lineage cells was moderately reduced post-implantation. Viability in the Ti implant group remained at approximately 86%, while in the ATZ group, it was observed at 75%, which is considered acceptable. Moreover, there was a significant disparity in cell survival between the two implant groups ( < 0.05). Analysis of apoptosis levels at various concentrations revealed that the rate of apoptosis was 3.6% in the control group and 18.5% in the ATZ group, indicating that apoptosis or programmed cell death in the ATZ-treated group had increased nearly four-fold ( < 0.05).
CONCLUSIONS
The findings of this study indicate a reduction in osteoblastic cell line survival following implant treatment, with titanium implants exhibiting superior performance in terms of cell survival. However, it was also noted that the incidence of apoptosis in osteoblast cells was significantly higher in the presence of zirconium-based implants.
Topics: Zirconium; Titanium; Osteoblasts; Aluminum Oxide; Cell Survival; Apoptosis; Animals; Dental Implants; Humans; Cell Proliferation; Cells, Cultured; Surface Properties
PubMed: 38927122
DOI: 10.3390/biom14060719 -
Periodontology 2000 Jun 2024The purpose of this review was to summarize the evidence with regard to behavioral and psychosocial assessment of the periodontitis patient, the candidate for implant... (Review)
Review
The purpose of this review was to summarize the evidence with regard to behavioral and psychosocial assessment of the periodontitis patient, the candidate for implant therapy, and the peri-implantitis patient. Periodontitis has an adverse effect on quality of life and its treatment can lead to significant improvements experienced by the patient. The latter is true for rehabilitation with dental implants, although patients harbor diverse expectations and perceptions of implant therapy, which can often interfere with satisfaction and/or influence long-term success. A thorough behavioral assessment of the candidate for implant therapy is essential, which should include, perceptions, expectations, as well as risk for behavioral disorders. Remedial action is essential to correct misperceptions and any identified risks. Finally, patients have limited awareness of limited ability to identify signs of peri-implantitis. The diagnosis of peri-implantitis can be a cause of significant distress, resentment, and loss of trust to the treatment and the caregivers. Despite documented value in clinical research, currently available instruments assessing patient-reported outcomes have little application in day-to-day clinical practice. Face-to-face patient to doctor open-ended communication remains the most effective way to comprehensively establish the long-term "therapeutic alliance" essential for the long journey for the periodontitis patient.
PubMed: 38927002
DOI: 10.1111/prd.12589 -
International Journal of Oral and... Jun 2024This study aimed to determine the accuracy of large language models (LLMs) in answering oral and maxillofacial surgery (OMS) multiple choice questions. A total of 259...
This study aimed to determine the accuracy of large language models (LLMs) in answering oral and maxillofacial surgery (OMS) multiple choice questions. A total of 259 questions from the university's question bank were answered by the LLMs (GPT-3.5, GPT-4, Llama 2, Gemini, and Copilot). The scores per category as well as the total score out of 259 were recorded and evaluated, with the passing score set at 50%. The mean overall score amongst all LLMs was 62.5%. GPT-4 performed the best (76.8%, 95% confidence interval (CI) 71.4-82.2%), followed by Copilot (72.6%, 95% CI 67.2-78.0%), GPT-3.5 (62.2%, 95% CI 56.4-68.0%), Gemini (58.7%, 95% CI 52.9-64.5%), and Llama 2 (42.5%, 95% CI 37.1-48.6%). There was a statistically significant difference between the scores of the five LLMs overall (χ = 79.9, df = 4, P < 0.001) and within all categories except 'basic sciences' (P = 0.129), 'dentoalveolar and implant surgery' (P = 0.052), and 'oral medicine/pathology/radiology' (P = 0.801). The LLMs performed best in 'basic sciences' (68.9%) and poorest in 'pharmacology' (45.9%). The LLMs can be used as adjuncts in teaching, but should not be used for clinical decision-making until the models are further developed and validated.
PubMed: 38926015
DOI: 10.1016/j.ijom.2024.06.003 -
Journal of Prosthodontic Research Jun 2024This study aimed to evaluate the 10-year outcomes of partial fixed dental prostheses (P-FDPs) fabricated using metal-free fiber-reinforced composite (FRC) resin...
PURPOSE
This study aimed to evaluate the 10-year outcomes of partial fixed dental prostheses (P-FDPs) fabricated using metal-free fiber-reinforced composite (FRC) resin frameworks veneered with composite resin and supported by short and extra-short implants.
METHODS
This study included 28 patients with 38 FRC prostheses supported by 96 implants. Implant and prosthesis survival and success rates were evaluated using Kaplan-Meier analysis.
RESULTS
The 10-year implant survival and success rate, as determined by Kaplan-Meier analysis, was 96.9%, and the prosthesis survival and success rates were 94.7% and 92.0%, respectively. None of the parameters under investigation were significantly correlated with prosthetic survival or successful outcomes, but three parameters were correlated with higher peri-implant bone levels: implant placement in the mandible as opposed to the maxilla, shorter P-FDP spans, and natural teeth on the opposing arch.
CONCLUSIONS
FRC P-FDPs supported by short and extra-short implants presented high, up to 10-year, survival and success rates, when used to restore partially edentulous arches.
PubMed: 38925987
DOI: 10.2186/jpr.JPR_D_23_00005 -
Journal of Prosthodontic Research Jun 2024Marginal bone loss (MBL) occurs in the periapical cervical bone after dental implant placement and abutment connection. MBL may not result in peri-implantitis; however,...
PURPOSE
Marginal bone loss (MBL) occurs in the periapical cervical bone after dental implant placement and abutment connection. MBL may not result in peri-implantitis; however, it is always accompanied by MBL. Recent studies have demonstrated that early MBL is a predictor of peri-implantitis. In this narrative review, we aimed to provide an evidence base for recommended treatment strategies for clinicians to prevent MBL.
STUDY SELECTION
We reviewed the recent literature and performed a narrative synthesis of the evidence, focusing on available systematic reviews and meta-analyses of implant marginal bone resorption.
RESULTS
The available evidence indicates that certain biological, material, and technical factors can influence MBL and consequently dictate the risk of developing peri-implant disease in later years. The order of the impact of the strength of each factor is unknown. Current recommendations to prevent MBL include controlling patients' smoking and hemoglobin A1c levels to sufficiently low levels before surgery and throughout their lifetime. Regarding the material, a platform-switching, conical-connecting implant system, and an abutment with a height of at least 2 mm should be selected. Placement should be performed using techniques that ensure sufficient soft tissue (keratinized gingival width > 2 mm, supracrestal tissue height > 3 mm), and non-undersized preparations in the cortical bone should be made with connected concave abutments during primary or secondary surgery. Patients should receive supportive peri-implant therapy during maintenance.
CONCLUSIONS
MBL development is multifactorial and can be reduced by considering the biological, material, and technical factors.
PubMed: 38925986
DOI: 10.2186/jpr.JPR_D_23_00223 -
Journal of Prosthodontic Research Jun 2024Occlusal overload can cause late implant loss. However, whether the magnitude of the occlusal force is a risk factor for late implant loss remains unclear. Thus, this...
PURPOSE
Occlusal overload can cause late implant loss. However, whether the magnitude of the occlusal force is a risk factor for late implant loss remains unclear. Thus, this clinical study aimed to determine the relationship between the gonial angle (GoA), which is associated with the magnitude of occlusal force, and late implant loss.
METHODS
All implants with fixed prostheses placed at the Niigata University Hospital between April 2006 and August 2019 were included in this retrospective study. The implants with and without late loss were compared. Relevant variables, including smoking habits, diabetes mellitus status, remaining dentition, implant length and diameter, prosthesis design, retention systems, splinting, and GoA were assessed. Log-rank test and Cox proportional hazards regression analysis were used to estimate the adjusted hazard ratio (aHR) and to calculate the corresponding 95% confidence intervals (CI) for late implant loss.
RESULTS
A total of 919 patients (349 men and 570 women) with 2512 implants were included in this study. Cox proportional hazards regression analysis revealed that a 10° decrease in the GoA (aHR, 1.588; 95% CI, 1.115-1.766; P = 0.010), smoking habits (aHR, 3.909; 95% CI, 2.131-7.168; P < 0.001), and male sex (aHR, 2.584; 95% CI, 1.376-4.850; P = 0.003) were significantly associated with late implant loss.
CONCLUSIONS
Within the limitations of this retrospective study of 2512 implants, smaller GoA, smoking habits, and male sex were risk factors for late implant loss.
PubMed: 38925984
DOI: 10.2186/jpr.JPR_D_23_00267