Comparative analysis of optical and numerical models for reflectance and color prediction of monolithic dental resin composites with varying thicknesses.

Objective: To assess the prediction accuracy of recent optical and numerical models for the spectral reflectance and color of monolithic samples of dental materials with different thicknesses.

Methods: Samples of dental resin composites of Aura Easy Flow (Ae1, Ae3 and Ae4 shades) and Estelite Universal Flow Super Low (A1, A2, A3, A3.5, A4 and A5 shades) with thicknesses between 0.

Biomechanical influence of narrow-diameter implants placed at the crestal and subcrestal level in the maxillary anterior region. A 3D finite element analysis.

Purpose: To evaluate the tendency of movement, stress distribution, and microstrain of single-unit crowns in simulated cortical and trabecular bone, implants, and prosthetic components of narrow-diameter implants with different lengths placed at the crestal and subcrestal levels in the maxillary anterior region using 3D finite element analysis (FEA).

Materials And Methods: Six 3D models were simulated using Invesalius 3.0, Rhinoceros 4.

A Multicentric Prospective Study on Maxillofacial Trauma Due to Road Traffic Accidents: The World Oral and Maxillofacial Trauma Project.

The purpose of this prospective multicenter study was to analyze the epidemiology, patterns, and management of maxillofacial fractures due to road traffic accidents (RTAs) worldwide.Between Monday September 30, 2019 and Sunday October 4, 2020,1066 patients with RTAs related fractures were admitted to 14 maxillofacial surgery departments. The following data were analyzed: age, gender, mechanism of injury, alcohol or drug abuse at the time of trauma, maxillofacial fracture site, facial injury severity scale (FISS) score, associated injuries, day and month of trauma, time of treatment, type of treatment and length of hospital stay.

World Oral and Maxillofacial Trauma (WORMAT) project: A multicenter prospective analysis of epidemiology and patterns of maxillofacial trauma around the world.

Background/aim: The World Oral Maxillofacial Trauma (WORMAT) project was performed to analyze the causes and characteristics of maxillofacial fractures managed in 14 maxillofacial surgery divisions over a 1-year period.

Methods: The following data were collected: age, sex, cause and mechanism of maxillofacial fracture, alcohol and/or drug abuse at the time of trauma, fracture site, Facial Injury Severity Scale score (FISS), associated injury, day of trauma, timing and type of treatment, and length of hospitalization. Statistical analyses were performed using SPSS software.

A multicentric prospective analysis of maxillofacial trauma in the elderly population.

Background/aims: The growth of the global elderly population will lead to an increase in traumatic injuries in this group, including those affecting the maxillofacial area, with a heavier load on health systems. The aim of this multicentric prospective study was to understand and evaluate the incidences, causes and patterns of oral and maxillofacial injuries in patients aged over 60 years admitted to 14 maxillofacial surgical departments around the world.

Methods: The following data were collected: gender, cause and mechanism of maxillofacial fracture, alcohol and drug abuse at the time of trauma, fracture site, Facial Injury Severity Scale score, associated injury, day of trauma, timing and type of treatment and length of hospitalization.

Biomechanical effect of an occlusal device for patients with an implant-supported fixed dental prosthesis under parafunctional loading: A 3D finite element analysis.

Statement Of Problem: Whether providing an occlusal device for a patient with bruxism and an implant-supported fixed dental prosthesis leads to improved biomechanics is unclear.

Purpose: The purpose of this 3D finite element analysis (FEA) study was to evaluate the biomechanical behavior of 3-unit implant-supported prostheses under parafunctional forces with and without an occlusal device.

Materials And Methods: Eight 3D models consisting of a posterior (type IV) maxillary bone block with 3 external hexagon implants (Ø4.

Evaluation of Guided Bone Regeneration in Critical Defects Using Bovine and Porcine Collagen Membranes: Histomorphometric and Immunohistochemical Analyses.

Guided bone regeneration (GBR) is a technique used to facilitate bone regeneration, which uses a biocompatible membrane acting as a physical barrier to prevent the adjacent connective tissue from invading the bone defect. The aim of this study was to evaluate and compare the effectiveness of bovine and porcine collagenous membranes as barriers to connective tissue invasion during the repair of critical bone defects in rat calvaria, using histological, histometric, and immunohistochemical analyses. For this study, 72 rats were divided into three groups: clot group (CG), bovine collagen group (BCG), and porcine collagen group (PCG).

Clinical comparison between crestal and subcrestal dental implants: A systematic review and meta-analysis.

Statement Of Problem: How the performance of dental implants is related to their occlusogingival placement, crestal or subcrestal, is unclear.

Purpose: The purpose of this systematic review and meta-analysis was to evaluate marginal bone loss, implant survival rate, and peri-implant soft tissue parameters between implants placed at the crestal and subcrestal bone level.

Material And Methods: Two independent reviewers searched the PubMed/MEDLINE, Embase, and Cochrane Library databases for randomized clinical trials published up to September 2020.

A 3D Finite Element Analysis of Bone Tissue in 3-Unit Implant-Supported Prostheses: Effect of Splinting Factor and Implant Length and Diameter.

This study aimed to assess the effects of splinting in 3-unit implant-supported prostheses with varying the splinting factor, length of the implant, and the diameter of the 1°molar (1°M) implant on cortical bone tissue (CBT). Twelve 3D models were simulated, which represented the posterior maxillary with 3 implants, supporting 3-unit FDP varying the splinting factor (single-unit crowns, splinted crowns straight-line and offset implant configuration [OIC]), length of the implant (7mm and 8,5mm), and the diameter of the 1°M (Ø4 mm and Ø5 mm). The CBT was analyzed by maximum principal stress and microstrain maps.

Surgical Treatment of Bilateral Atrophic Mandible Fracture.

Poor proprioception, weakness, and impaired reflexes increase the incidence of facial fracture in the elderly. Mandibular fractures in these people range from 10.1% to 56%.

A Novel Analysis via Micro-CT Imaging Indicates That Chemically Modified Tetracycline-3 (CMT-3) Inhibits Tooth Relapse after Orthodontic Movement: A Pilot Experimental Study.

Objective: To evaluate the effect of chemically modified tetracycline-3 (CMT-3) and simvastatin on tooth relapse after orthodontic movement in rats using a novel analysis method employing high-resolution micro-CT (Micro-CT) images. In addition, the correlation between bone density and orthodontic relapse was also evaluated for each experimental group.

Methods: Forty adult male Wistar rats had stainless steel springs installed on their left upper first molars in order to generate tooth movement for 18 days.

Bone regeneration with recombinant human bone morphogenetic protein 2: a systematic review.

Aim: The aim of this work was to perform a systematic literature review on the clinical application of rhBMP-2 in bone reconstruction prior to placing implants.

Materials And Methods: A PUBMED search was made about the subject and nine clinical trials were selected according to strict inclusion criteria.

Results: Overall success rates of bone regeneration with rhBMP-2 was 81.

Lipoma on the Lower Lip.

Lipoma is a benign tumor of fat tissue, found frequently in subcutaneous tissues. However, oral manifestations are relatively rare. The present patient illustrates the successful treatment of a lipoma treated by complete excision of the lesion.

Assessment of bone repair in critical-size defect in the calvarium of rats after the implantation of tricalcium phosphate beta (β-TCP).

Objectives: Evaluating the osteoconductive property of tricalcium phosphate beta (β-TCP) in comparison to that of inorganic bovine bone for repair in a critical-size defect in the rat calvarium.

Materials And Methods: Critical-size defects of 7mm were made with a trephine in the calvaria of 48 Wistar rats. The animals were divided into four groups, and the defects in each group were filled with tricalcium phosphate beta (β-TCP), inorganic bovine bone (Bio-Oss), autogenous bone, or left empty.

Surgical Treatment of Posttraumatic Ophthalmoplegia Through the Reconstruction of the Lateral Orbital Wall.

Orbital fractures are injuries frequently related to traumas of the midface. These fractures can be associated with ocular lesions, ranging from small abrasions on the cornea to serious complications such as hyphema and ocular globe rupture. Diplopia and ophthalmoplegia are common findings in orbital fractures.

Influence of post-etching surface treatment and thermo-mechanical cycling on fracture strength of ceramics.

Backgroung: The aim of this study was to evaluate fracture strength of lithium disilicate-based ceramic crowns submitted to neutralization of hydrofluoric acid (HF) precipitates associated with ultrasonic bath and to thermo-mechanical cycling.

Methods: Eighty human molars received conventional full crown preparation after being included in polyurethane standard to simulate periodontal ligament. After scanning, the ceramic blocks were machined using CAD/CAM system to obtain the crowns.

Reconstruction of Frontal Bone With Custom-Made Prosthesis Using Rapid Prototyping.

Frontal bone fracture treatment is still an issue of research in craniofacial surgery and neurosurgery. The aims of the treatment are to reduce the complication risks and to keep the aesthetic of the face. Before the management of this fracture type, it is necessary to consider the permanence or not of the frontal sinus function.

Work-related activities that may contribute to musculoskeletal symptoms among dental students: validation study.

Background: Dentists are exposed to occupational hazards, such as musculoskeletal disorders, in which symptoms can manifest early in clinical practice.

Objectives: To estimate the reliability and validity of the Portuguese version of the "Questionnaire on work-related activities that may contribute to musculoskeletal symptoms" when applied to dental students.

Methods: 553 Brazilian students participated in the study.