Sharif Digital Repository

Dentistry technology has been developed drastically during past two decades and the application of software and automated digital equipment have been proposed to have the most influence. Digital dental workflow includes four phases: scan, design, production planning and production which in each of the phases, the various software packages and digital devices are required. In addition, workflow in dentistry requires intensive cooperation among dentists, dental laboratories, technicians, imaging and production centres. This paper has developed anovel platform for digital dentistry, which facilitates the interoperability among different digital components and improves digital workflow in... 

Due to the important role of commitment and trust in the relationship marketing, the factors which can directly result in a committed relationship along with the factors which can influence the commitment through influencing trust, according to the model of commitment and trust by (Morgan & Hunt, 1994) have been introduced and their level of importance has been investigated here. The article uses fuzzy cognitive maps (FCMs) in the proposed model to find the most important paths leading to relationship commitment. The FCM analyzes the responses of a group of 30 people including general practitioners in dentistry, managers of dental departments in some of the public clinics and hospitals who... 

Objectives: Detecting caries lesions is challenging for dentists, and deep learning models may help practitioners to increase accuracy and reliability. We aimed to systematically review deep learning studies on caries detection. Data: We selected diagnostic accuracy studies that used deep learning models on dental imagery (including radiographs, photographs, optical coherence tomography images, near-infrared light transillumination images). The latest version of the quality assessment tool for diagnostic accuracy studies (QUADAS-2) tool was used for risk of bias assessment. Meta-analysis was not performed due to heterogeneity in the studies methods and their performance measurements.... 

Introduction of digital solutions has made dentistry more efficient and effective in response to patients’ demands. Moreover, digital solution helps participants to manage daily workflow simpler than traditional practices. Scanners, CAD/CAM software, CNC machines and 3D printers are components of digital solutions in current dentistry. Responding to patients as quickly as possible is essential in medical fields and dentistry has similar situations. On the other hand, demands in dentistry are highly customized that it makes managing orders more difficult because each order needs special design and production. Thus, this paper assesses orders in digital dentistry and develops a mathematical... 

Recent enhancements in computer aided design and manufacturing have made dentistry workflow more effective. Dental products are highly customized and personalized for patients. So, they require manufacturing processes for flexibility and agility and fulfilling requirements like quality, delivery time and cost. Various types of scanners, design software and production devices are used by stakeholders in digital dentistry. Also, other stakeholders such as dentists, dental surgeons and lab technicians work together to respond to patient demands to produce the required products while they are distributed in different geographical locations. This paper introduces a new practical and... 

This article presents a method for determination of meshing force distribution on contact region of spur gear teeth. In this method it is assumed that there are inter-connected springs on the teeth profile. These springs treat as capacitive fields. The compliance matrices of these fields are determined from the results of finite element analysis done on 3-D model of a gear. The tooth compliance matrix is used as a reference data to determine the tooth deformations for any meshing situation. The meshing force distribution is calculated using this reference data and Hertz theory for contacting bodies. The results of this analysis help in stress analysis under real operation conditions and more... 

Radiopacity is sometimes an essential characteristic of biomaterials that can help clinicians perform follow-ups during pre- and post-interventional radiological imaging. Due to their chemical composition and structure, most bioceramics are inherently radiopaque but can still be doped/mixed with radiopacifiers to increase their visualization during or after medical procedures. The radiopacifiers are frequently heavy elements of the periodic table, such as Bi, Zr, Sr, Ba, Ta, Zn, Y, etc., or their relevant compounds that can confer enhanced radiopacity. Radiopaque bioceramics are also intriguing additives for biopolymers and hybrids, which are extensively researched and developed nowadays for... 

Background: Most dentists complain of musculoskeletal disorders which can be caused by prolonged static posture lack of suitable rest and other physical and psychological problems. Objective: We evaluated a chair with a new ergonomic design which incorporated forward leaning chest and arm supports. Methods: The chair was evaluated in the laboratory during task simulation and EMG analysis on 12 students and subjectively assessed by 30 professional dentists using an 18-item questionnaire. EMG activity of right and left trapezius muscles for 12 male students with no musculoskeletal disorders was measured while simulating common tasks like working on the teeth of the lower jaw. Results:... 

Purpose: The purpose of this paper is to evaluate the galvanic corrosion of nitinol orthodontic wires with six dental alloys in artificial saliva and consider the effect of initiated localized corrosion and real surfaces of anode and cathode on galvanic current. Design/methodology/approach: Linear polarization and cyclic polarization curves for each alloy in de-aerated Duffo and Castillo's artificial saliva are obtained. Galvanic corrosion investigation is conducted by polarization curve intersection and mixed potential theory methods. In order to verify the initiation of localized corrosion, scanning electron microscopy is used. Findings: Initiation of localized corrosion on the anode... 

This article presents a routine for prediction of the crack growth path in gears. Crack simulation helps in determining failure modes and crack detecting by vibration monitoring. To simulate crack propagation an effective method is developed by which the meshing force is calculated based on the compliance of meshing teeth in every stage of crack growth. In this method the compliance matrix of the tooth is calculated using three-dimensional boundary element analysis without the need for simultaneously modelling two meshing gears. The force distribution on the contact area is then calculated using Hertz theory and compliance matrices of meshing teeth. The method is used in prediction of the...