Perception of Dental Esthetics: Influence of Restoration Type, Symmetry, and Color in Four Different Countries

2015 ◽  
Vol 28 (1) ◽  
pp. 60-64 ◽  
Author(s):  
Christian Mehl ◽  
Sönke Harder ◽  
Jun Lin ◽  
Oliver Vollrath ◽  
Matthias Kern
2020 ◽  
Vol 02 ◽  
Author(s):  
Pia Chatterjee Kirk

Background: Vital tooth whitening has become an integral part of esthetic dentistry and remains one of the safest and most economic options today to improve dental esthetics without removing tooth structure. The tooth whitening materials have evolved into three categories: dentist-prescribed/dispensed (in office and patient home-use), and over-thecounter purchased and applied by patients. Objective: This review outlines the latest advances in dentist prescribed vital teeth whitening techniques, effects on tooth structure, soft tissues, and dental restoratives. Areas requiring additional research are also discussed. Methods: Electronic and manual literature search was conducted for key words such as tooth bleaching, and dental bleaching techniques using PubMed/MEDLINE, followed by manual selection of the studies that included whitening procedures in vital teeth. Results: The two main whitening agents are carbamide peroxide (CP) and hydrogen peroxide (HP or H2O2) whose concentration, duration of contact, and total treatment time can alter results. In addition, factors including the type of stain, and age of patient can affect results. Although whitening agents can affect tooth structure, restorative materials, and gingival tissues, the changes are temporary or can be treated using minimally invasive techniques. Conclusion: Areas requiring further research include the actual mechanism of whitening, its effect on tooth structure and restorative materials, and the development of an easy method to quantitate the degree of whitening in the dental office.


Philosophy ◽  
2020 ◽  
Vol 96 (1) ◽  
pp. 99-131
Author(s):  
Niels de Haan

AbstractThere is good reason to think that moral responsibility as accountability is tied to the violation of moral demands. This lends intuitive support to Type-Symmetry in the collective realm: A type of responsibility entails the violation or unfulfillment of the same type of all-things-considered duty. For example, collective responsibility necessarily entails the violation of a collective duty. But Type-Symmetry is false. In this paper I argue that a non-agential group can be collectively responsible without thereby violating a collective duty. To show this I distinguish between four types of responsibility and duty in collective contexts: corporate, distributed, collective, shared. I set out two cases: one involves a non-reductive collective action that constitutes irreducible wrongdoing, the other involves a non-divisible consequence. I show that the violation of individual or shared duties both can lead to irreducible wrongdoing for which only the group is responsible. Finally, I explain why this conclusion does not upset any work on individual responsibility.


2013 ◽  
Vol 333 ◽  
pp. 335-359 ◽  
Author(s):  
P.M. Zhang ◽  
P.A. Horvathy ◽  
K. Andrzejewski ◽  
J. Gonera ◽  
P. Kosiński
Keyword(s):  

Symmetry ◽  
2018 ◽  
Vol 10 (11) ◽  
pp. 601
Author(s):  
Orest Artemovych ◽  
Alexander Balinsky ◽  
Denis Blackmore ◽  
Anatolij Prykarpatski

The Lie algebraic scheme for constructing Hamiltonian operators is differential-algebraically recast and an effective approach is devised for classifying the underlying algebraic structures of integrable Hamiltonian systems. Lie–Poisson analysis on the adjoint space to toroidal loop Lie algebras is employed to construct new reduced pre-Lie algebraic structures in which the corresponding Hamiltonian operators exist and generate integrable dynamical systems. It is also shown that the Balinsky–Novikov type algebraic structures, obtained as a Hamiltonicity condition, are derivations on the Lie algebras naturally associated with differential toroidal loop algebras. We study nonassociative and noncommutive algebras and the related Lie-algebraic symmetry structures on the multidimensional torus, generating via the Adler–Kostant–Symes scheme multi-component and multi-dimensional Hamiltonian operators. In the case of multidimensional torus, we have constructed a new weak Balinsky–Novikov type algebra, which is instrumental for describing integrable multidimensional and multicomponent heavenly type equations. We have also studied the current algebra symmetry structures, related with a new weakly deformed Balinsky–Novikov type algebra on the axis, which is instrumental for describing integrable multicomponent dynamical systems on functional manifolds. Moreover, using the non-associative and associative left-symmetric pre-Lie algebra theory of Zelmanov, we also explicate Balinsky–Novikov algebras, including their fermionic version and related multiplicative and Lie structures.


2019 ◽  
Vol 22 (1) ◽  
pp. Process
Author(s):  
Shereen Ahmed Nossair ◽  
Tarek Salah ◽  
Kamal Khaled Ebeid

Objective: This study was designed to evaluate the biaxial flexural strength (BFS) of different types of unshaded and shaded monolithic zirconia. Material and Methods: 120 monolithic zirconia ceramic discs were fabricated. They were divided into twelve groups (n=10), Group 1; Bruxzir unshaded, Group 2; Bruxzir shaded A2, Group 3; Bruxzir anterior white, Group 4; Bruxzir anterior shade A2, Group 5; Prettau unshaded, Group 6; Prettau shaded with A2 coloring liquid, Group 7; Prettau anterior white, Group 8; Prettau anterior shaded with A2 coloring liquid, Group 9; Katana HT white, Group 10; Katana HT shade A2, Group 11; Katana ST white, Group 12; Katana ST shade A2. All discs were milled using a dental milling machine, and had final dimensions after sintering of 15 mm diameter and 1 mm thickness. BFS was tested using piston on three ball technique. Results:  One-way ANOVA revealed significant differences among the 12 groups. Tukey post-hoc tests revealed no significant differences between the groups 3, 4, ,7 ,8 11, and 12. However, they all had BFS values that are significantly lower than all other groups. Group 2 showed statistically significant higher BFS values when compared to group 3,4, 7, 8, 11, and 12 while it showed statistically significant lower values when compared to groups 1, 5, 6, 9, and 10. Conclusion: Increase in the yttria content in zirconia led to a decrease in its BFS. Shading of zirconia did not have a significant effect on the final strength of zirconia. KeywordsDental ceramics; Dental esthetics; Flexural strength; Shaded zirconia. 


Author(s):  
Yue-Liang Wu

Starting from the motional property of functional field based on the action principle of path integral formulation while proposing maximum coherence motion principle and maximum locally entangled-qubits motion principle as guiding principles, we show that such a functional field as fundamental building block appears naturally as an entangled qubit-spinor field expressed by a locally entangled state of qubits. Its motion brings about the appearance of Minkowski space–time with dimension determined by the motion-correlation [Formula: see text]-spin charge and the emergence of [Formula: see text]-spin/hyperspin symmetry as fundamental symmetry. Intrinsic [Formula: see text]-spin charge displays a periodic feature as the mod 4 qubit number, which enables us to classify all entangled qubit-spinor fields and space–time dimensions into four categories with respect to four [Formula: see text]-spin charges [Formula: see text]. An entangled decaqubit-spinor field in 19-dimensional hyper-space–time is found to be a hyperunified qubit-spinor field which unifies all discovered leptons and quarks and brings on the existence of mirror lepton–quark states. The inhomogeneous hyperspin symmetry [Formula: see text] as hyperunified symmetry in association with inhomogeneous Lorentz-type symmetry [Formula: see text] and global scaling symmetry provides a unified fundamental symmetry. The maximum locally entangled-qubits motion principle is shown to lay the foundation of hyperunified field theory, which enables us to comprehend long-standing questions raised in particle physics and quantum field theory.


2018 ◽  
Vol 1 (2) ◽  
pp. 93
Author(s):  
Fidiyah Inayati ◽  
I Gusti Aju Wahju Ardani

Background: Patients with congenital absence of a mandibular lateral incisor are often found having difficulty in achieving adequate functional occlusion. It may affect esthetics, mastication, speech, and occlusal balance. Purpose: This paper reported an agenesis treatment of one mandibular lateral incisor case using a space closure method. Case: A twenty-three years old female patient with agenesis of tooth 42, mandibular anterior crowding, multiple diastema on mandibular anterior teeth, and skeletal class III malocclusion. Case Management: Space closure method was chosen to correct the agenesis by considering the class III skeletal malocclusion and multiple diastema condition. Conclusion: Space closure method treatment improved the patient’s facial and dental esthetics, and it provided a good functional occlusion, despite the absence of a mandibular lateral incisor, which generally impairs the adequate incisal guidance.


2016 ◽  
Vol 2016 ◽  
pp. 1-12 ◽  
Author(s):  
Fernando Pedrin Carvalho Ferreira ◽  
Anderson Paulo Barbosa Lima ◽  
Eliana de Cássia Molina de Paula ◽  
Ana Claudia de Castro Ferreira Conti ◽  
Danilo Pinelli Valarelli ◽  
...  

Improving facial and dental appearance and social interaction are the main factors for special needs (SN) patients to seek orthodontic treatment. The cooperation of SN patients and their parents is crucial for treatment success.Objective. To show through a case report the satisfactory results, both functional and esthetic, in patients with intellectual disability, congenital nystagmus, and severe scoliosis.Materials Used. Pendulum device with mini-implants as anchorage unit.Results. Improvement of facial and dental esthetics, correction of Class II malocclusion, and no root resorption shown in the radiographic follow-up.Conclusion. Knowing the limitations of SN patients, having a trained team, motivating and counting on the cooperation of parents and patients, and employing quick and low-cost orthodontic therapy have been shown to be the essential factors for treatment success.


Sign in / Sign up

Export Citation Format

Share Document