Irfan Ahmad

Irfan Ahmad

Doctor of Dental Surgery

About

87
Publications
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1,515
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Publications

Publications (87)
Article
Full-text available
The rehabilitation of anterior dental aesthetics involves a multitude of disciplines, each with its own methodologies for achieving a predefined goal. The literature is awash with different techniques for a given predicament, based on both scientific credence, as well as empirical clinical judgements. An example is crown lengthening for correcting...
Book
Full-text available
A digital impression A virtual design A 3D-printed restoration A bioprinted bone scaffold The future of dentistry is here! Exciting, innovative and unimaginable – 3D printing offers all this and more... Thirty years ago, the invention by Charles Hull of SLA (stereolithographic apparatus), or 3D printing, began a revolution in the way dentistry is...
Book
Full-text available
An accessible, one-stop guide to getting the most out of dental photography in clinical practice
Chapter
Digital dental photography consists of extra-oral, intra-oral, portraiture and bench images. Before embarking on a photographic session, it is impor- tant to decide on the intended use of the images. Dental photography can simply be photodocumentation for facilitating a specific treatment or used for marketing, teaching or artistic endeavours. Clin...
Chapter
Shade evaluation and colour science are often misunderstood and daunting since most members of the dental team have little or no formal training about the subject. This shortcoming leads to confusion, adopting hearsay information without scientific backing and ultimately compromising aesthetic dental treatment. Although the dental literature is awa...
Chapter
Besides photographic equipment, there are additional items required for taking intra‐oral pictures, as well as specific clinical considerations to bear in mind. The majority of these requisite items are readily available as part of the dental armamentarium, but a few need to be acquired. Emphasising the importance of cross‐infection control to dent...
Article
The process of tooth eruption consists of two phases, active and passive. While the distinction is unequivocal, the mechanism is ambiguous. This article compares and contrasts altered passive eruption (APE) and active secondary eruption (ASE). Although these phases present with similar clinical manifestations, each has its own etiology, physiogenes...
Patent
Full-text available
Read requests to a commonly accessed storage volume are conditionally issued, depending on whether or not a requested data block is already stored in memory from a prior access or to be stored in memory upon completion of a pending request. A data structure is maintained in memory to track physical memory pages and to indicate for each physical mem...
Patent
Full-text available
Activity level of memory pages is classified in virtual machine environment, so that processes such as live VM migration and checkpointing, among others, can be carried out more efficiently. The method includes the steps of scanning page table entries of hypervisor-managed page tables continuously over repeating scan periods to determine whether me...
Patent
Full-text available
Distributed storage resources having multiple storage units are managed based on data collected from online monitoring of workloads on the storage units and performance characteristics of the storage units. The collected data is sampled at discrete time intervals over a time period of interest, such as a congested time period. Normalized load metri...
Patent
Full-text available
In one embodiment, a latency value is determined for an input/output IO request in a host computer of a plurality of host computers based on an amount of time the IO request spent in the host computer's issue queue. The issue queue of the host computer is used to transmit IO requests to a storage system shared by the plurality of host computers. Th...
Patent
Full-text available
One or more embodiments of the present invention provide a technique for effectively managing virtualized computing systems with an unlimited number of hardware resources. Host systems included in a virtualized computer system are organized into a scalable, peer-to-peer (P2P) network in which host systems arrange themselves into a network overlay t...
Patent
Full-text available
An anomaly in a shared input/output (IO) resource that is accessed by a plurality hosts or clients is detected when a host that is not bound by any QoS policy presents large workloads to a shared IO resource that is also accessed by hosts or clients that are governed by QoS policy. The anomaly detection triggers a response from the hosts or clients...
Patent
Full-text available
Activity level of memory pages is repeatedly classified in a virtual machine environment, so that live VM migration can be carried out more efficiently. The time intervals upon which the activity level of the memory pages are repeatedly classified can be dynamically adjusted to better align its performance with the live VM migration process.
Patent
Full-text available
Two shared data structures are maintained in a storage unit for coordinating statistic collection among multiple hosts that share the storage unit. The first data structure stores information about the number of hosts that possess slots within the second data structure and identifying information about the slots. The second data structure maintains...
Patent
Full-text available
A method for measuring latencies caused by processing performed within a common resource is provided. A current latency value representing a time of residency of an IO request in a queue prior to receipt of acknowledgment from the common resource of completion of the IO request is received from a device comprising the queue, which maintains entries...
Patent
Full-text available
Techniques are disclosed for managing memory within a virtualized system that includes a memory compression cache. Generally, the virtualized system may include a hypervisor configured to use a compression cache to temporarily store memory pages that have been compressed to conserve memory space. A “first-in touch-out” (FITO) list may be used to ma...
Article
Objective The aim of the current study was to investigate the psychosocial impact of dental aesthetics among patients who received anterior implant-supported prostheses.Methods The current study is a cross-sectional evaluation involving 115 individuals who had gone through treatment at the dental clinics of general hospitals. Participants completed...
Article
Full-text available
Virtualized datacenters strive to reduce costs through workload consolidation. Workloads exhibit a diverse set of IO behaviors and varying IO load that makes it difficult to estimate the IO performance on shared storage. As a result, system administrators often resort to gross overprovisioning or static partitioning of storage to meet application d...
Article
Full-text available
Managing resources at large scale while providing per-formance isolation and efficient use of underlying hard-ware is a key challenge for any cloud management soft-ware. Most virtual machine (VM) resource management systems like VMware DRS clusters, Microsoft PRO and Eucalyptus, do not currently scale to the number of hosts and VMs supported by clo...
Conference Paper
Storage management in virtualized environments is considered as one of the biggest cost factors. According to some estimates, majority of the cost and performance problems are related to storage devices. In this tutorial, we will discuss some of the key storage technologies deployed in virtual datacenters. We will discuss a set of unique challenges...
Conference Paper
Interrupt coalescing is a well known and proven technique for reducing CPU utilization when processing high IO rates in network and storage controllers. Virtualization introduces a layer of virtual hardware for the guest operating system, whose interrupt rate can be controlled by the hypervisor. Unfortunately, existing techniques based on high-reso...
Article
Full-text available
After the demise of the Industrial Age, we currently live in an 'Information Age' fuelled mainly by the Internet, with an ever-increasing medically and dentally literate population. The media has played its role by reporting scientific advances, as well as securitising medical and dental practices. Reality television such as 'Extreme makeovers' has...
Conference Paper
Full-text available
Live migration of virtual hard disks between storage arrays has long been possible. However, there is a dearth of online tools to perform automated virtual disk placement and IO load balancing across multiple storage arrays. This problem is quite challenging because the performance of IO workloads depends heavily on their own characteristics and th...
Article
Full-text available
This part of our series specifically addresses extra-oral dental photography consisting of portraiture and dental laboratory pictures. Portraiture, which is achieved using three types of illumination, natural daylight, bi-lateral camera mounted flashes (as for intra-oral images) or studio flashes, can be further divided into full face and dento-fac...
Article
Full-text available
The majority of pictures taken in the dental surgery are intra-oral and this article looks at the practicalities involved in full-arch, quadrant occlusal, lingual (or palatal) and lateral views, as well as magnified images, oral mucosa, enamel texture, dentine strata and shade analysis for artificial restorations. Additionally, the issue of cross-i...
Article
Full-text available
Having successfully taken a digital image, the next step is deciding what to do with it. Should it be cropped, correctly orientated, manipulated, compressed, scaled, sharpened, archived (and if so, which file format is the most suitable), or even discarded? The premise of this part of our series is to answer these and other questions related to pos...
Article
Full-text available
The final part of this series on digital dental photography details how to use images to their maximum potential. The purpose and uses of dental photography have previously been covered in Part 2, and the ensuing discussion concentrates on the technical aspects of printing, publishing and audio-visual presentations.
Article
Full-text available
Effective lighting is the key to success in all photography but particularly in dental photography. This part of the series on digital dental photography examines the colour/space/time triad which is achieved by the presence and manipulation of light, be it daylight, flashlight or other forms of illumination. In addition, the effect of reflectors i...
Article
Full-text available
Once the appropriate camera and equipment have been purchased, the next considerations involve setting up and calibrating the equipment. This article provides details regarding depth of field, exposure, colour spaces and white balance calibration, concluding with a synopsis of camera settings for a standard dental set-up.
Article
Full-text available
With so many cameras and systems on the market, making a choice of the right one for your practice needs is a daunting task. As described in Part 1 of this series, a digital single reflex (DSLR) camera is an ideal choice for dental use in enabling the taking of portraits, close-up or macro images of the dentition and study casts. However, for the s...
Article
Full-text available
Although the primary purpose of using digital photography in dentistry is for recording various aspects of clinical information in the oral cavity, other benefits also accrue. Detailed here are the uses of digital images for dento-legal documentation, education, communication with patients, dental team members and colleagues and for portfolios, and...
Article
Full-text available
Although we live in a digital age, our knowledge of the processes and technology involved is often limited. As a foundation to understanding the subsequent parts of this series, this part describes the fundamental aspects of digital photography, which includes the sensors, processing and display.
Article
Full-text available
This paper is the first article in a new ten-part series on digital dental photography. Part 1 previews and outlines the contents of the subsequent papers and in addition, defines the aims and objectives of a digital dental image and the features that are required for an ideal intra-oral picture.
Article
Full-text available
Virtualization has been effective in providing performance isolation and proportional allocation of resources, such as CPU and memory between VMs by using automated distributed resource schedulers and VM migration. Storage VMotion allows users to migrate virtual hard disks from one data store to another without stopping the virtual machine. There i...
Conference Paper
Full-text available
Rapid adoption of virtualization technologies has led to increased utilization of physical resources, which are mul- tiplexed among numerous workloads with varying demands and importance. Virtualization has also accelerated the de- ployment of shared storage systems, which offer many ad- vantages in such environments. Effective resource manage- men...
Article
Full-text available
Server virtualization is accelerating the already existing need for shared storage area network (SAN) infrastructure for the associated benefits of migration, flexible manage-ment and economies of sharing. Understanding the charac-teristics of a workload in terms of access locality, IO sizes, read write ratio etc. is crucial for effective placement...
Article
Full-text available
Interrupt coalescing is a proven technique for reducing CPU utilization when processing high IO rates in storage and networking controllers. Virtualization introduces a layer of virtual hardware whose interrupt rate can be con-trolled by the hypervisor. In this paper, we present the design and implementation of a virtual interrupt coalesc-ing schem...
Article
Full-text available
Deployment of shared storage systems is increasing with rapid adoption of virtualization technologies to provide i so- lation, better management and high utilization of resource s. Quality of service (QoS) in such environments is quite de- sirable for meeting IO demands of virtual machines. The lack of QoS support at typical storage arrays, simulta...
Chapter
Aesthetic dentistry has become increasingly important to dentists and their patients. This book is designed as a springboard to assist clinicians in developing the aesthetic potential of restorative procedures. The book marries evidence-based principles with handy hints and tips the author has distilled from years of clinical experience. This combi...
Chapter
Half TitleTitleCopyrightContentsDedicationForewordPreface
Conference Paper
Collection of detailed characteristics of disk I/O for workloads is the first step in tuning disk subsystem performance. This paper presents an efficient implementation of disk I/O workload characterization using online histograms in a virtual machine hypervisor VMware ESX Server. This technique allows transparent and online collection of essential...
Article
Full-text available
Welcome to the second article in the Vital Guide Series. Here, Irfan Ahmad points out the seven deadly sins of aesthetic dentistry and how to spot them. Test yourself by answering our CPD questions, which are designed to get you thinking about the article and to help you remember some of the key points. The answers to the questions in the spring is...
Article
Full-text available
Unlabelled: Ceramics were invented by the Chinese during the T'ang Dynasty, where they quickly became a precious commodity. By the early 18th Century, ceramics found its way into dentistry due to its high strength, biocompatibility, and malleability. Today, ceramic materials are a staple in dentistry, available in both naturally based and partiall...
Article
Full-text available
The purpose of this series is to convey the principles governing our aesthetic senses. Usually meaning visual perception, aesthetics is not merely limited to the ocular apparatus. The concept of aesthetics encompasses both the time-arts such as music, theatre, literature and film, as well as space-arts such as paintings, sculpture and architecture.
Article
Full-text available
The purpose of this series is to convey the principles governing our aesthetic senses. Usually meaning visual perception, aesthetics is not merely limited to the ocular apparatus. The concept of aesthetics encompasses both the time-arts such as music, theatre, literature and film, as well as space-arts such as paintings, sculpture and architecture.
Article
Full-text available
The purpose of this series is to convey the principles governing our aesthetic senses. Usually meaning visual perception, aesthetics is not merely limited to the ocular apparatus. The concept of aesthetics encompasses both the time-arts such as music, theatre, literature and film, as well as space-arts such as paintings, sculpture and architecture.
Article
Full-text available
The purpose of this series is to convey the principles governing our aesthetic senses. Usually meaning visual perception, aesthetics is not merely limited to the ocular apparatus. The concept of aesthetics encompasses both the time-arts such as music, theatre, literature and film, as well as space-arts such as paintings, sculpture and architecture.
Article
Full-text available
The purpose of this series is to convey the principles governing our aesthetic senses. Usually meaning visual perception, aesthetics is not merely limited to the ocular apparatus. The concept of aesthetics encompasses both the time — arts such as music, theatre, literature and film, as well as space — arts such as paintings, sculpture and architect...
Article
Significant material advancements have resulted in the increased application of porcelain materials as an ideal restorative substitute for tooth enamel and dentin. This discussion introduces a synthetic, low-fusing, quartz glass-ceramic system for the fabrication of fixed dental prostheses. This article evaluates and compares the properties of this...
Article
Dentistry is often described as a fusion of art and science. While the scientific aspect is well documented, the artistic component is nebulous and often subject to interpretation. The use of the word "aesthetic" as a description of artistic dentistry is essentially flawed. While it forms part of artistic concepts, aesthetics is not the quintessent...
Article
This paper discusses the use of four types of ceramics; zirconia, leucite reinforced glass, densely-sintered pure aluminium oxide and a low fusing porcelain, for the restitution of anterior aesthetics. Recent advances in dental ceramic technology have made this scenario a reality, which only a decade ago, was thought elusive. While ceramics offer o...
Article
In addition to outlining the fundamental principles of color and its qualitative and quantitative measurement, the first part of this article explained the chemical, physical, physiological, and psychological realization of color. To complete this discussion, the second part focuses on numerous variables that affect shade determination in the clini...
Article
The purpose of this article is to demonstrate the versatil- ity and enhanced aesthetic results provided by laboratory- fabricated composite resin restorations. This discussion describes the scientific premise of polyglass materials and applies these principles in two case presentations. While the ensuing results are readily available with contempo-...
Article
Although color is evident in daily function, it is often misunderstood and obscured by misconceptions. While the literature focuses on mathematical formulas and specific facets of color, little research exists on the fundamental aspects of color realization. This article demonstrates the principles of color, which include definitions, measurements,...
Article
Due to their enhanced optical properties (eg, translucency, value, chroma), ceramic systems can provide natural aesthetics for restorations placed in the anterior segment. In endodontically treated teeth with stained dentin, however, the use of translucent ceramic materials may be contraindicated unless the underlying discoloration can be masked. T...
Article
In the pursuit of esthetic restorations for nonvital teeth, the introduction of a tooth-colored intraradicular post system is described. Conventional metallic posts can corrode and may cause inflammatory reactions and discoloration of the periodontium. Zirconium dioxide is a chemically stable ceramic with physical and optical properties that make i...
Article
While aesthetics is traditionally regarded as an artistic concept, quantifiable scientific principles are used in its development. Dental aesthetics are governed by mathematical parameters that, when applied by the clinician and laboratory technician, can achieve restorations with a unique aesthetic appearance. These geometric laws should not be vi...
Article
Three new species of Hemicycliophora are described and illustrated. Hemicycliophora altapadii sp.n. is characterized by its relatively large body size; conoid lip region with three annules, indented dorsovcntrally; a rectangular oral disc; elongated vulval lips; absence of longitudinal lines and R>370. H. meghalayaensis sp.n. also has a relatively...
Article
Criconemoides chamoliensis n. sp. is characterized by 54-65 ornamented body annules, absence of submedian lobes, enlarged pseudolips connected laterally, stylet 64-75 μm long and acutely conoid tail. Mesocriconema paronostris (Deswal & Bajaj, 1987) is redescribed with SEM illustrations.
Article
Full-text available
Des populations d'#Hemicycliophora dhirendri$ Husain & Khan, 1967 provenant d'Aligarh, la localité type, et de Saharanpur, U.P. (Inde) ont été étudiées de façon détaillée. Les comparaisons faites avec #H. labiata$ Colbran, 1960 indiquent que ces deux espèces sont presque indistinguables l'une de l'autre. En conséquence, #H. dhirendri$ doit être con...
Article
Full-text available
Deux nouvelles espèces de #Plectidae$ sont décrites et illustrées. #Tylocephalus palmatus$ n. sp. présente les caractères suivants : L = 0,41-0,61 mm; a = 14-18; b = 3,6-4,3; c = 13,1-13,9; V = 42-49. Cette nouvelle espèce est proche de #T. auriculatus$ (Buetschli, 1873) Anderson, 1966 et de #T. andinus$ Zell, 1993. #Plectus refusus$ n. sp. présent...
Article
Full-text available
Two new species of Chronogaster in India were described and illustrated, based on light and scanning electron microscopy. Chronogaster neotypica n. sp. collected from a sewage slurry was characterized by a medium-sized body, a ventral tail mucro without additional spines, absence of longitudinal incisures in lateral fields, and by the presence of c...
Article
Full-text available
SEM observations were made on the morphology of the nygolaim, Laevides symmetricus Khan et al., 1990 and its embryonic development was studied. The cuticle is marked with fine transverse striations, lips are amalgamated with an asteroid oral aperture and the papillae arranged in a 6 + 10 pattern. Mural tooth with slit-like laterodorsal aperture. Ve...
Article
Detailed SEM observations were made on Tobrilus paludicola Micoletzky, 1925 and on its developmental biology. The cuticle is marked with fine transverse striations. The lip region is continuous and lips are broadly triangular in shape. The labial papillae are in a 6+6+4 arrangement. Amphids are small, ovoid, post-labial apertures. Embryonic develop...
Article
Full-text available
Detailed SEM observations were made on Mononchoides fortidens (Schuurmans Stekhoven, 1951) Taylor & Hechler, 1966. The cuticle is marked with fine transverse striations and prominent longitudinal ridges or folds. The lip region is continuous and the lips are not prominent. Each lip bears a single papilla but in males four additional setose cephalic...
Article
Full-text available
Scleroactinolaimus n. gen. is distinguished by its unusual cheilostomal armature consisting of four sclerotized vertical plates in addition to four onchia. The new genus is related to Egtitus Thorne, 1967, Neoactinolaimus Thorne, 1967 and Mactinolaimus Andrássy, 1970 but differs from them in the nature of cheilostomal armature and an unusually slen...
Article
Full-text available
SUMMARY Diploscapter orientalis reproduces parthenogenetically. The eggs are elongate, measuring 45-55 x 20-30 pm with blunt spines on their surface. Most eggs are laid in the single ce11 stage. Hatching takes about 13-17 h from the time of oviposition. The newly hatched juveniles lack labial hooks which develop later in the second stage juveniles....
Article
Full-text available
Detailed observations have been made on Doylaimus stagnalis with the scanning electron microscope. The cuticle on the lip region is sculptured, lips are amalgamated and provided with the usual sixteen sensilla. The longitudinal ridges (bands) on the cuticle are made up of four to seven discrete cuticular folds. The ridges which extend from the neck...
Article
Mononchoides fortidens reproduced by amphimixis. Smooth, elongate eggs measuring 60-80 x 35-45 μm were laid in single-cell stage. Embryonic and post-embryonic development lasted for 16-20 h and 3-6 days respectively. Sexes were first distinguished during second moulting by the anterior elongation of primordium in males and anterior as well as poste...

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Projects

Projects (6)
Project
A comprehensive update of Prosthodontics at a Glance (First Edition)
Project
Co-authored with Fahad Al-Harbi. This book is a guide for all dental disciplines and specialities, covering a practical approach for achieving consistently predictable and repeatable high quality documentation.
Project
Clinical decision making for treating fluorosed teeth