Retention forces between primary and secondary CAD/CAM manufactured telescopic crowns: an in vitro comparison of common material combinations.

Objectives: To analyze the retention forces between primary and secondary telescopic crowns milled from various materials and to compare them with the retention forces between cast telescopic crowns made of precious metal alloys.

Materials And Methods: Primary and secondary crowns (N = 60; n = 10 per group) were fabricated using various material combinations (1: zirconia [ZIR]/polyether ether ketone [PEEK]; 2: titanium grade IV [TI]/PEEK; 3: PEEK/PEEK; 4: non-precious alloy [NPA]/PEEK; 5:NPA/NPA), while precious alloy (PA) was used for the control group (6: PA/PA). The retention forces at 10, 1000, 5000, and 10,000 connection and disconnection cycles and the relative weights were analyzed, applying nonparametric repeated measures ANOVA and post hoc Mann-Whitney and Wilcoxon signed-rank tests (α < 0.

CBCT imaging and histopathological characteristics of osteoradionecrosis and medication-related osteonecrosis of the jaw.

Purpose: The purpose of this study was to evaluate the cone-beam computed tomographic (CBCT) imaging and histopathological characteristics of osteoradionecrosis (ORN) and medication-related osteonecrosis of the jaw (MRONJ).

Materials And Methods: Ten surgical specimens from segmental mandibulectomy (3 ORN and 7 MRONJ) were analyzed using CBCT. The CBCT parameters were as follows: high-resolution mode (tube voltage, 90.

Effects of porcelain veneering methods on conformity of the marginal and internal fit of three-unit zirconia framework.

The purpose of this study is to investigate the effects of porcelain veneering methods on the marginal and internal fit of a three-unit zirconia framework. A zirconia master model, in which the lower-left second premolar and the second left molar were used as the abutment, was obtained using an intraoral scanner. Based on the data, three-unit zirconia frameworks for fabricating all-ceramic bridges were designed and milled (FW group).

Pulp tissue reaction to a self-adhesive, resin-based direct pulp capping material containing surface pre-reacted glass-ionomer filler.

Objective: This study aimed to evaluate the effect of direct pulp capping using an experimental self-adhesive resin for direct pulp capping (SRD) containing silica and surface pre-reacted glass-ionomer (S-PRG) filler on pulpal healing and to monitor the dentin bridge formation in rat pulp 2-4 weeks after operation.

Methods: Five types of SRDs (SRD-0: S-PRG fillers 0 wt%; SRD-1: S-PRG fillers 9.1 wt%; SRD-2: S-PRG fillers 18.

Estimation of the Periodontal Inflamed Surface Area by Simple Oral Examination.

The periodontal inflamed surface area (PISA) is a useful index for clinical and epidemiological assessments, since it can represent the inflammation status of patients in one contentious variable. However, calculation of the PISA is difficult, requiring six point probing depth measurements with or without bleeding on probing on 28 teeth, followed by data input in a calculation program. More simple methods are essential for screening periodontal disease or in epidemiological studies.

The Effects of Differences in the Morphologies of the Ulnar Collateral Ligament and Common Tendon of the Flexor-Pronator Muscles on Elbow Valgus Braking Function: A Simulation Study.

The anterior bundle (AB) and posterior bundle (PB) of the ulnar collateral ligament and the anterior common tendon (ACT) and posterior common tendon (PCT) of the flexor-pronator muscles have an independent form and an unclear form. The purpose of this study was to clarify the effect of differences in the morphologies of the AB, PB, ACT, and PCT on the elbow valgus braking function. This investigation examined three elbows.

Collagen-Based Matrices for Osteoconduction: A Preclinical In Vivo Study.

The aim of this study was to evaluate the influence of additional hydroxyapatite (HA) in collagen-based matrices (CM) and membrane placement on bone formation in calvarial defects. Critical size defects in the calvaria of 16 New Zealand White Rabbits were randomly treated with CM or mineralized collagen-based matrices (mCM). Half of the sites were covered with a collagen membrane.

Effect on thickness of a single-layer mouthguard of positional relationship between suction port of the vacuum forming device and the model.

Background/aim: Wearing a mouthguard reduces the risk of sport-related injuries, but the thickness has a large effect on its efficacy and safety. The aim of this study was to investigate the effect on the thickness of a single-layer mouthguard of the positional relationship between the suction port of the vacuum forming device and the model.

Materials And Methods: Ethylene-vinyl-acetate sheets of 4.

Coevolution of enamel, ganoin, enameloid, and their matrix SCPP genes in osteichthyans.

We resolve debate over the evolution of vertebrate hypermineralized tissues through analyses of matrix protein-encoding secretory calcium-binding phosphoprotein (SCPP) genes and phylogenetic inference of hypermineralized tissues. Among these genes, and are found in both sarcopterygians and actinopterygians, whereas and are found only in sarcopterygians and actinopterygians, respectively. Actinopterygian , , and are expressed during the formation of hypermineralized tissues on scales and teeth: ganoin, acrodin, and collar enamel in gar, and acrodin and collar enameloid in zebrafish.

Fabrication of vacuum-formed and pressure-formed mouthguards using polyolefin sheet.

Background: Mouthguard should be worn to decrease orofacial trauma. Custom-made mouthguards are usually fabricated using ethylene vinyl acetate sheet or polyolefin sheet. However, the difference of the characteristics of the mouthguard formed by polyolefin sheet has not been cleared enough.

Relationships between the upper central incisor crown forms and degree of labial inclination, overbite, and overjet in Japanese young adults.

Purpose: The present study aimed to investigate the relationships between the crown form of the upper central incisor and their labial inclination, overbite, and overjet.

Materials And Methods: Maxillary and mandibular casts of 169 healthy dentitions were subjected to 3D dental scanning, and analyzed using CAD software. The crown forms were divided into tapered, square, and ovoid based on the mesiodistal dimensions at 20% of the crown height to that at 40%.

Association between Drinking Habits and Oral Symptoms: A Cross-Sectional Study Based on Japanese National Statistical Data.

Aim: The purpose of this study was to investigate the association between drinking habits and subjective symptoms of the oral cavity based on Japanese national statistical data.

Methods: The subjects were 8,698 respondents of the Japan National Livelihood Survey 2013, in their 30s to 60s. The association between drinking habits and each survey item was investigated by contingency table analysis and binary logistic regression analysis.

In vitro Activity of Oral Health Care Products on Candida Biofilm Formation.

The activity of mouthwash ingredients used in daily oral care (chlorhexidine digluconate, benzalkonium chloride, povidone iodine solution, tea tree oil) and of nystatin was evaluated not only on planktonic Candida albicans or C. glabrata, but also on the inhibition of biofilm formation. A microbroth dilution technique was used to determine the minimum inhibitory concentration of the substances against two laboratory strains and seven clinical isolates.

Morphological characteristics of the plantar calcaneocuboid ligaments.

Background: The aim of this study was to clarify the differences in morphological features between the long plantar ligament (LPL) and the short plantar ligament (SPL).

Methods: This investigation examined 50 legs from 25 Japanese cadavers. The LPL and SPL of each leg were classified into one of three types based on the shape and number of fiber bundles.

Effects of plastic bracket primer on the shear bond strengths of orthodontic brackets.

Background/purpose: To assess the usefulness of plastic bracket primer (PBP) for improving the bond strength of plastic brackets (PBs) using three types of orthodontic brackets, including PBs, metal brackets (MBs), and ceramic brackets (CBs).

Materials And Methods: A total of 162 premolars were gathered and divided equally into six groups of 27. Three groups were tested with the application of PBP (PB+, MB+, and CB+), and three groups were tested without primer (groups PB-, MB-, and CB-).

Questionnaire survey of angiogenesis inhibitor-related oral complications based on a nation-wide study in Japan.

Background/purpose: The prevalence of oral adverse events and dental treatments related complications during the molecular targeted drugs therapy remains unclear. The purpose of this study was to investigate the contents of dental treatment-related complications in Japanese patients during molecular targeted therapy.

Materials And Methods: The nation-wide survey of dental treatment related complications was performed by the Japanese Society of Dentistry for Medically Compromised Patient as retrospective cohort study.

Difference in laminated mouthguard thickness according to the laminate order.

Background/aim: Mouthguard thickness should be maintained to prevent oral trauma by protecting the teeth and the surrounding soft tissue. The aim of this study was to examine the difference in laminated mouthguard thickness according to the laminate order.

Materials And Methods: The mouthguard sheets used in this study were 2.

A multicenter prospective cohort study on the effect of smoking cessation on periodontal therapies in Japan.

Few prospective studies have reported the effects of periodontal therapy on patients who attempted to quit smoking. This study aimed to assess how smoking cessation affects periodontal therapy. Twenty-five smokers with periodontitis were investigated by dividing them into two groups, a smoking cessation support group and a continued smoking group.

Quantitative evaluation of elasticity of lower orbicularis oris muscle during the lip closing measurement using sonographic elastography.

Background: Lip closing functions have never been evaluated from the viewpoint of elastic properties.

Objectives: The purpose of the present study was to investigate the behavior of the lower orbicularis oris muscle during a button-pull exercise to measure lip closing force and quantitatively evaluate its elastic properties using sonographic elastography.

Methods: Appropriate compression loads for elastography were randomly measured on one of three types of acoustic couplers on three examiners.

Dental implant care and trouble among dependent patients based on the questionnaire survey among Japanese dental practitioners.

Background: Self-care and professional care of implants may prove difficult for elderly people who require nursing care. However, the actual state of care and problems remains unknown. In this study, we investigated the actual state of implant problems in elderly people living in their own home or in a nursing home who received visiting dental treatment.

Marginal and internal fit of three-unit fixed dental prostheses fabricated from translucent multicolored zirconia: Framework versus complete contour design.

Statement Of Problem: Translucent multicolored zirconia materials enable more esthetic complete contour zirconia fixed dental prostheses (FDPs) than conventional zirconia, which exhibits low translucency and high opacity and is monochromatic. However, how the marginal and internal fit of translucent multicolored zirconia FDPs compare with those of traditional frameworks that require veneering is unclear.

Purpose: The purpose of this in vitro study was to compare the marginal and internal fit of frameworks and complete contour 3-unit FDPs fabricated from translucent multicolored zirconia.