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1.
Materials (Basel) ; 17(13)2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38998421

RESUMO

This study aimed to histologically evaluate the effects of XPEED® and SLA surface on the mineral apposition rate (MAR) at 3 and 5 weeks in titanium dental implants placed in human bone. In total, 17 titanium dental implants with XPEED® surface (n = 9) used as test and SLA surface (n = 8) used as control were included in this study. Each patient received four doses of tetracycline 500 mg at 12 h intervals 2 weeks prior to biopsy retrieval. Implant retrieval was performed, and retrieved biopsies were carefully treated for histomorphometric evaluation under epifluorescence microscopy. At 3 and 5 weeks, newly formed bone appeared in direct contact with both types of tested surfaces. At 3 weeks, the MAR value was, respectively, 2.0 (±0.18) µm/day for XPEED® implants and 1.5 (±0.10) µm/day for SLA implants (p = 0.017). At 5 weeks, lower MAR values for both XPEED® and SLA implants were noted, with 1.2 (±0.10) µm/day and 1.1 (±0.10) µm/day, respectively (p = 0.046). The overall evaluation by linear regression analysis for both time and implant surfaces showed a decreased osteoblast activity at 5 weeks compared to 3 weeks (p < 0.005). The results of the present study show that the bone apposition rate occurs faster around implants with XPEED® surface at 3 weeks and 5 weeks of healing. MAR values may support the use of implants with XPEED® surfaces in early loading protocols.

2.
Materials (Basel) ; 17(10)2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38793397

RESUMO

Titanium implants undergo an aging process through surface hydrocarbon deposition, resulting in decreased wettability and bioactivity. Plasma treatment was shown to significantly reduce surface hydrocarbons, thus improving implant hydrophilicity and enhancing the osseointegration process. This study investigates the effect of plasma surface treatment on bone-to-implant contact (BIC) of implants presenting a nanostructured calcium-incorporated surface (XPEED®). Following a Randomized Controlled Trial (RCT) design, patients undergoing implant surgery in the posterior maxilla received additional plasma-treated (n = 7) or -untreated (n = 5) 3.5 × 8 mm implants that were retrieved after a 4-week healing period for histological examination. Histomorphometric analysis showed that plasma-treated implants exhibited a 38.7% BIC rate compared to 22.4% of untreated implants (p = 0.002), indicating enhanced osseointegration potential. Histological images also revealed increased bone formation and active osteoblastic activity around plasma-treated implants when compared to untreated specimens. The findings suggest that plasma treatment improves surface hydrophilicity and biological response, facilitating early bone formation around titanium implants. This study underscores the importance of surface modifications in optimizing implant integration and supports the use of plasma treatment to enhance osseointegration, thereby improving clinical outcomes in implant dentistry and offering benefits for immediate and early loading protocols, particularly in soft bone conditions.

3.
Front Bioeng Biotechnol ; 11: 1201177, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37456726

RESUMO

The biomechanics of transplanted teeth remain poorly understood due to a lack of models. In this context, finite element (FE) analysis has been used to evaluate the influence of occlusal morphology and root form on the biomechanical behavior of the transplanted tooth, but the construction of a FE model is extremely time-consuming. Model order reduction (MOR) techniques have been used in the medical field to reduce computing time, and the present study aimed to develop a reduced model of a transplanted tooth using the higher-order proper generalized decomposition method. The FE model of a previous study was used to learn von Mises root stress, and axial and lateral forces were used to simulate different occlusions between 75 and 175N. The error of the reduced model varied between 0.1% and 5.9% according to the subdomain, and was the highest for the highest lateral forces. The time for the FE simulation varied between 2.3 and 7.2 h. In comparison, the reduced model was built in 17s and interpolation of new results took approximately 2.10-2s. The use of MOR reduced the time for delivering the root stresses by a mean 5.9 h. The biomechanical behavior of a transplanted tooth simulated by FE models was accurately captured with a significant decrease of computing time. Future studies could include using jaw tracking devices for clinical use and the development of more realistic real-time simulations of tooth autotransplantation surgery.

4.
Sci Rep ; 13(1): 2598, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36788333

RESUMO

Lack of evidence exists related to the investigation of the accuracy and efficacy of novice versus experienced practitioners for dental implant placement. Hence, the following in vitro study was conducted to assess the accuracy of implant positioning and self-efficacy of novice compared to experienced surgeons for placing implant using freehand (FH), pilot drill-based partial guidance (PPG) and dynamic navigation (DN) approaches. The findings revealed that DN significantly improved the angular accuracy of implant placement compared with FH (P < 0.001) and PPG approaches (P < 0.001). The time required with DN was significantly longer than FH and PPG (P < 0.001), however, it was similar for both novice and experienced practitioners. The surgeon's self-confidence questionnaire suggested that novice practitioners scored higher with both guided approaches, whereas experienced practitioners achieved higher scoring with PPG and FH compared to DN. In conclusion, implant placement executed under the guidance of DN showed high accuracy irrespective of the practitioner's experience. The application of DN could be regarded as a beneficial tool for novices who offered high confidence of using the navigation system with the same level of accuracy and surgical time as that of experienced practitioners.


Assuntos
Implantes Dentários , Cirurgiões , Cirurgia Assistida por Computador , Humanos , Projetos de Pesquisa , Duração da Cirurgia
5.
J Clin Periodontol ; 50(4): 500-510, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36574768

RESUMO

AIM: Alveolar ridge resorption following tooth extraction often renders a lateral bone augmentation inevitable. Some patients, however, suffer from severe early (during graft healing, Eres ) and/or late (during follow-up, Lres ) graft resorption. We explored the hypothesis that the "individual phenotypic dimensions" may partially explain the degree of such resorptions. MATERIALS AND METHODS: Patients who underwent a guided bone regeneration (GBR) procedure were screened for inclusion according to the following criteria: (1) a relatively symmetrical maxillary arch; (2) an intact contra-lateral alveolar bone dimension; (3) the availability of a pre-operative cone-beam CT (CBCT); (4) a CBCT taken immediately after GBR, and (5) at least one CBCT scan ≥6 months after surgery. CBCT scans from different timepoints were registered and imported into the Mimics software (Materialise, Leuven, Belgium). Bone dimensions of the contra-lateral site of the augmentation, representing the "individual phenotypical dimension (IPD) of the alveolar crest", were superimposed on the augmented site and registered accordingly. As such, Eres and Lres could be measured over time, in relation to the IPD (in two dimensions; per millimetre apically from the alveolar crest, in the centre of the GBR), as well as in three dimensions (the entire GBR, 2 mm away from the mesial, distal, and apical border for standardization). RESULTS: A total of 17 patients (23 augmented sites) were included. After Eres , the outline of the augmentation was in general located ±1 mm outside the IPD, but ≥1.5 years after GBR, it further moved towards the IPD (85% within 0.5 mm distance). CONCLUSIONS: Within the limitations of this study, the results indicate that the dimensions of a lateral bone augmentation are defined by the "individual phenotypic bone boundaries" of the patient.


Assuntos
Perda do Osso Alveolar , Aumento do Rebordo Alveolar , Humanos , Transplante Ósseo/métodos , Perda do Osso Alveolar/diagnóstico por imagem , Perda do Osso Alveolar/cirurgia , Implantação Dentária Endóssea/métodos , Processo Alveolar/diagnóstico por imagem , Processo Alveolar/cirurgia , Regeneração Óssea , Aumento do Rebordo Alveolar/métodos
6.
Int J Implant Dent ; 8(1): 42, 2022 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-36210395

RESUMO

PURPOSE: This study aimed to investigate the performance of novice versus experienced practitioners for placing dental implant using freehand, static guided and dynamic navigation approaches. METHODS: A total of 72 implants were placed in 36 simulation models. Three experienced and three novice practitioners were recruited for performing the osteotomy and implant insertion with freehand, surgical guide (pilot-drill guidance) and navigation (X-Guide, X-Nav technologies) approaches. Each practitioner inserted 4 implants per approach randomly with a 1-week gap to avoid memory bias (4 insertion sites × 3 approaches × 6 practitioners = 72 implants). The performance of practitioners was assessed by comparing actual implant deviation to the planned position, time required for implant placement and questionnaire-based self-confidence evaluation of practitioners on a scale of 1-30. RESULTS: The navigation approach significantly improved angular deviation compared with freehand (P < 0.001) and surgical guide (P < 0.001) irrespective of the experience. Surgical time with navigation was significantly longer compared to the freehand approach (P < 0.001), where experienced practitioners performed significantly faster compared to novice practitioners (P < 0.001). Overall, self-confidence was higher in favor of novice practitioners with both guided approaches. In addition, the confidence of novice practitioners (median score = 26) was comparable to that of experienced practitioners (median score = 27) for placing implants with the navigation approach. CONCLUSIONS: Dynamic navigation system could act as a viable tool for dental implant placement. Unlike freehand and static-guided approaches, novice practitioners showed comparable accuracy and self-confidence to that of experienced practitioners with the navigation approach.


Assuntos
Implantes Dentários , Cirurgia Assistida por Computador , Implantação Dentária Endóssea , Osteotomia
7.
Clin Oral Investig ; 26(8): 5117-5128, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35687196

RESUMO

The dental practice has largely evolved in the last 50 years following a better understanding of the biomechanical behaviour of teeth and its supporting structures, as well as developments in the fields of imaging and biomaterials. However, many patients still encounter treatment failures; this is related to the complex nature of evaluating the biomechanical aspects of each clinical situation due to the numerous patient-specific parameters, such as occlusion and root anatomy. In parallel, the advent of cone beam computed tomography enabled researchers in the field of odontology as well as clinicians to gather and model patient data with sufficient accuracy using image processing and finite element technologies. These developments gave rise to a new precision medicine concept that proposes to individually assess anatomical and biomechanical characteristics and adapt treatment options accordingly. While this approach is already applied in maxillofacial surgery, its implementation in dentistry is still restricted. However, recent advancements in artificial intelligence make it possible to automate several parts of the laborious modelling task, bringing such user-assisted decision-support tools closer to both clinicians and researchers. Therefore, the present narrative review aimed to present and discuss the current literature investigating patient-specific modelling in dentistry, its state-of-the-art applications, and research perspectives.


Assuntos
Inteligência Artificial , Cirurgia Bucal , Tomografia Computadorizada de Feixe Cônico/métodos , Humanos , Modelagem Computacional Específica para o Paciente , Medicina de Precisão
8.
J Dent ; 116: 103891, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34780873

RESUMO

OBJECTIVES: The objective of this study is the development and validation of a novel artificial intelligence driven tool for fast and accurate mandibular canal segmentation on cone beam computed tomography (CBCT). METHODS: A total of 235 CBCT scans from dentate subjects needing oral surgery were used in this study, allowing for development, training and validation of a deep learning algorithm for automated mandibular canal (MC) segmentation on CBCT. Shape, diameter and direction of the MC were adjusted on all CBCT slices using a voxel-wise approach. Validation was then performed on a random set of 30 CBCTs - previously unseen by the algorithm - where voxel-level annotations allowed for assessment of all MC segmentations. RESULTS: Primary results show successful implementation of the AI algorithm for segmentation of the MC with a mean IoU of 0.636 (± 0.081), a median IoU of 0.639 (± 0.081), a mean Dice Similarity Coefficient of 0.774 (± 0.062). Precision, recall and accuracy had mean values of 0.782 (± 0.121), 0.792 (± 0.108) and 0.99 (± 7.64×10-05) respectively. The total time for automated AI segmentation was 21.26 s (±2.79), which is 107 times faster than accurate manual segmentation. CONCLUSIONS: This study demonstrates a novel, fast and accurate AI-driven module for MC segmentation on CBCT. CLINICAL SIGNIFICANCE: Given the importance of adequate pre-operative mandibular canal assessment, Artificial Intelligence could help relieve practitioners from the delicate and time-consuming task of manually tracing and segmenting this structure, helping prevent per- and post-operative neurovascular complications.


Assuntos
Aprendizado Profundo , Tomografia Computadorizada de Feixe Cônico Espiral , Inteligência Artificial , Tomografia Computadorizada de Feixe Cônico , Humanos , Processamento de Imagem Assistida por Computador , Canal Mandibular
9.
Case Rep Dent ; 2017: 9315070, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29362679

RESUMO

Different techniques for the enucleation of jaw cyst lesion in the oral and maxillofacial regions have been proposed, including the bone lid technique. The purpose of this case report is to describe the case of a cystic lesion, approached with the bone lid technique performed using a piezoelectric device, with an 8-month clinical and radiographic follow-up. A 14-year-old male patient was treated for a suspicious lesion detected on a panoramic radiograph. The concerned area was surgically accessed, and a radiographically predetermined bony window was drawn, and the beveled bony lid was removed. The underlying lesion was enucleated and sent for pathology as a routine procedure, and the removed bony lid was repositioned in situ and secured with a collagen tape. Healing was uneventful with limited swelling and reduced pain. A complete radiographic bone healing at the previously diseased site was confirmed with an 8-month cone beam computed tomography (CBCT) scan with no buccal bone resorption nor ridge collapse. The bone lid technique with a piezoelectric device was noninvasive and atraumatic in this case. Further studies are needed and could lead to the adaptation of this approach as a possible standard of care.

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