Khaled Khalaf

• PhD, BDS, LDS (A), DAS (Orth.), FDS (Orth) RCS (Eng), FFDRCSI (Orth.), M Orth RCS (Eng), M Orth RCS (Edin), MFDSRCS (Eng), MFDSRCS (Edin), MFDSRCPS (Glasg), CASAP (T&L), FHEA (UK)
• Director of the Institute of Dentistry and Professor in Orthodontics at Institute of Dentistry University of Aberdeen UK

Background This study is a pioneer systematic review and meta-analysis aimed at comparing the influence of Class II and Class III skeletal malocclusions on pharyngeal airway dimensions. It stands as the inaugural comprehensive assessment to collate and analyze the disparate findings from previously published articles on this topic. The objective of...

The aim of this study is to investigate whether the genetic, epigenetic and environmental factors that give rise to supernumeraries in the maxillary incisor region and larger dimensions of the adjacent maxillary incisors are also associated with variations in the morphology of the mandibular incisors. If so, this would contribute to understanding t...

Background In recent years, social networking sites (SNSs) have evolved beyond connection and networking to become a powerful instructional tool. There is still a dearth of knowledge on the professional use of SNSs for education particularly among students from diverse backgrounds. This study examined the extent and pattern of SNSs usage for educat...

Objectives: The aim of this study was to evaluate senior students’ and dental graduates' perception of professionalism as defined by international regulatory bodies and to assess students’ ability to apply such knowledge in clinical-based scenarios. Materials and Methods: Knowledge of professional competencies was conducted using a survey based on...

Objectives: This study investigated the effect of learning by observation on the development of fine motor skills related to endodontic manual instrumentation. We evaluated if learning by observation with guidance had any influence upon operator performance under tense or taxing conditions. Materials and Methods: Dental students prepared standardi...

Background In recent years, social networking sites (SNSs) have evolved beyond connection and networking to become a powerful instructional tool. There is still a dearth of knowledge on the professional use of SNS for education particularly among students from diverse backgrounds. This study examined the extent and pattern of usage SNS in education...

Patients with hypodontia appear to have a different craniofacial morphology as compared with controls. They tend to have more class III skeletal pattern and retroclined upper and lower soft tissue lips as a consequence of retroclined upper and lower incisors. These features are more pronounced as the severity of the hypodontia increases. In additio...

Cervical root resorption is an uncommon, aggressive form of external resorption that occurs on the root surface of a permanent tooth and presents clinically as a characteristic pinkish discoloration of the tooth. The cause of cervical root resorption is poorly understood, and it has been suggested that orthodontic treatment may play a role in causi...

Background The aim of this systematic review was to address the clinical effectiveness of space maintainers and space regainers in the prevention and correction of dental arch decreases in mixed dentition. Methods An electronic search was conducted using five databases: the Cochrane Database for Systematic Reviews, EBSCO Host, ScienceDirect, PubMe...

Titanium particles as a product of degradation have been detected in periimplant oral tissues and it has been assumed that implants were the source of these particles. Periimplantitis sites had higher concentrations of particles in comparison to healthy implant sites. Several factors have been identified in the degradation of dental implant surface...

Titanium particles as a product of degradation have been detected in periimplant oral tissues and it has been assumed that implants were the source of these particles. Periimplantitis sites had higher concentrations of particles in comparison to healthy implant sites. Several factors have been identified in the degradation of dental implant surface...

Background Effective root canal treatment involves cleaning and shaping root canals using a range of instrumentation procedures and techniques. The aim of this review was to provide an update on root canal hand instrumentation techniques and how to overcome iatrogenic errors. Methods A comprehensive search was carried out using multiple databases,...

Background Professional competencies are integral part of the competent dental graduate that include professional attitude and behaviour, ethics and communication skills. The aim of this study was to evaluate senior students’ and dental graduates' perception of professionalism as defined by international regulatory bodies and to assess students’ ab...

Learning dental procedures is a complex task involving the development of fine motor skills. The reported use of theories and/ or evidence for designing learning activities to develop the fi-ne motor skills needed for dental practice is limited. The aim of this review is to explore the available body of knowledge related to learning motor skills re...

Objectives. To evaluate the effectiveness of rapid palatal expansion in the treatment of nocturnal enuresis among 6–18-year-old children and adolescents. Methods. Comprehensive searches were carried out in 6 electronic databases (EBSCO, ProQuest, Clinical Key, Science Direct, SCOPUS, and OVID) and supplemented by additional manual searches in 4 ort...

Purpose: Different approaches have been proposed to treat malocclusion secondary to the treatment of maxillofacial trauma. This study aimed to investigate the efficacy of prosthodontic treatment, orthodontic treatment, and implant-supported rehabilitation for the management of secondary malocclusion after maxillofacial trauma. Study selection: We...

Prior research has demonstrated that motor skill learning is often disrupted by self-focus and attempts to control movement. The propensity for reinvestment (i.e., self-focus and movement control) has been associated with poor motor skill learning in sport and surgery, but it has not yet been examined in dental education. Therefore, the aim of this...

Objectives: This study aims to evaluate the impact of stress on the clinical performance of endodontics dental students. Method: The study sample consists of 16 randomly selected fourth-year dental students who had completed pre-clinical activities stipulated in their curriculum. The distal canal of a plastic mandibular first molar is prepared on...

Learning dental procedures is a complex task involving the development of fine motor skills. The reported use of theories and/ or evidence for designing learning activities to develop the fine motor skills needed for dental practice is limited. The aim of this review is to explore the available body of knowledge related to learning fine motor skill...

This study aimed to evaluate the impact of errorless and errorful learning, on acquisition of root canal hand‐instrumentation skills. Dental students prepared standardised canals of different diameters and curvatures. Learning involved minimising (errorless: n = 21) or maximising errors (errorful: n = 21). Students who had completed accredited pre‐...

Background: The aim of this systematic review was to address the clinical effectiveness of space maintainers and space regainers in the prevention and correction of dental arch decrease in the mixed dentition. Methods: An electronic search was conducted using five databases and 6 relevant journals. Inclusion criteria were: Randomized Controlled Cli...

Introduction: Restorative dental treatment is a complex task involving various procedures which require the development and integration of both theoretical knowledge and fine motor skills. It aims to provide the theoretical background and role of key factors in learning these skills. Materials and Methods: The following electronic databases were s...

Objectives: The aim of the study was to evaluate the perception of smile aesthetics in patients with varying degrees of anterior crowding and spacing among dental specialists, dentists, dental students, and laypersons and to assess the effect of the lips position. Materials and methods: Clinical photos of cases of anterior crowding (mild, modera...

Introduction: Dental education involves teaching and assessing the acquisition of verifiable domains that require superior psychomotor, communication, and cognitive skills. Evolving technologies and methods of assessment could enhance student's learning environment and improve tutor assessment experience. The aim of this study was to review the cu...

Background: To investigate the effectiveness of technology-enhanced teaching and assessment methods of undergraduate preclinical skills in comparison to conventional methods. Methods: A comprehensive search strategy was implemented using both manual and electronic search methods, including PubMed, Wiley, ScienceDirect, SCOPUS, and the Cochrane C...

Abstract Background: To investigate the effectiveness of technology-enhanced teaching and assessment methods of undergraduate preclinical skills in comparison to conventional methods. Methods: A comprehensive search strategy was implemented using both manual and electronic search methods, including PubMed, Wiley, ScienceDirect, SCOPUS, and the Coc...

Background: To investigate the effectiveness of technology-enhanced teaching and assessment methods of undergraduate preclinical skills in comparison to conventional methods. Methods: A comprehensive search strategy was implemented using both manual and electronic search methods, including PubMed, Wiley, ScienceDirect, SCOPUS, and the Cochrane Cent...

Background: To investigate the effectiveness of technology-enhanced teaching and assessment methods of undergraduate preclinical skills in comparison to conventional methods. Methods: A comprehensive search strategy was implemented using both manual and electronic search methods, including PubMed, Wiley, ScienceDirect, SCOPUS, and the Cochrane Cent...

Background Dental education involves teaching and assessing the acquisition of verifiable domains that require superior psychomotor, communication, and cognitive skills. Evolving technologies and methods of assessment could enhance student learning environment and improve tutor assessment experience. Objective The aim of this study was to introduc...

Objectives The aim of this study was to compare root dimensions (length and mesiodistal widths) between subjects with mild hypodontia and an age- and sex-matched control group. Materials and Methods Root dimension measurements of all permanent teeth excluding third molars were made on standardly taken orthopantomograms of 50 individuals (25 hypodon...

Aim: The aim of this study was to investigate variations in the number of roots and root canals in first permanent lower molars (FPLMs) using cone beam computed tomography (CBCT). Materials and methods: A total of 640 CBCT images were analyzed using SIDEXIS XG software version 2.62 (Sirona Dental Systems, Bensheim, Germany). The entire root anat...

Design: Systematic review Data source: A search strategy was implemented using both manual hand search and electronic databases, including Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, ScienceDirect, Scopus and Ebsco. Study eligibility criteria: Randomized controlled clinical trials Participants: Children in the early or late mi...

An anterior crossbite is defined as an abnormal reversed labiolingual relationship of the incisors, where one or more primary or permanent maxillary incisors are located palatally to the mandibular incisors. The prevalence of the anterior crossbite in the literature varies between 2.2% and 12% depending on the age of patients, ethnicity of the incl...

Background Orthodontic tooth movement represents a series of events at both cellular and molecular levels which in turn stimulates inflammatory pathway to induce tooth movement. Some drugs taken by patients have a negative effect which can block this pathway, on the other hand, others may influence these events and reduce treatment time. Search Me...

Supernumerary teeth in the premolar region, unlike other supernumeraries, occur more often in the mandible where they are generally of the supplemental type. Occasionally, they are conical or smaller than normal, particularly in the upper premolar regions. -ey might occur singly or in multiples, be erupted or impacted, but the majority have been fo...

Hypodontia is defined as the condition in which there is one to six congenitally missing teeth excluding the third molars and is the most common developmental anomaly in humans with a reported range of 4.4% to 13.4%. It most commonly affects the permanent dentition, with the mandibular second premolars having the highest incidence followed by the m...

Self-perception of smile aesthetics has been suggested as the most common reason for seeking orthodontic treatment and a perfect aesthetic healthy smile has always been the desired goal for dental professionals. However, perception of smile aesthetics may vary between dental healthcare professionals and patients. Therefore, the purpose of this stud...

Self-perception of smile aesthetics has been suggested as the most common reason for seeking orthodontic treatment and a perfect aesthetic healthy smile has always been the desired goal for dental professionals. However, perception of smile aesthetics may vary between dental healthcare professionals and patients. Therefore, the purpose of this stud...

Objectives To compare tooth size between subjects with mild, moderate and severe hypodontia and a control group. Material and Methods The study comprised 120 patients with hypodontia divided into three groups of 40 mild (≤2 teeth congenitally missing), 40 moderate (3-5 teeth congenitally missing) and 40 severe (≥6 teeth congenitally missing) hypod...

The purpose of the present study is to investigate whether there are significant differences in the alveolar bone height of a group of individuals with mild hypodontia when compared to a matched in age and gender control group of unaffected individuals. A retrospective cross-sectional analytical study of panoramic radiographs (OPTs) of patients wit...

The congenital absence of a maxillary central incisor is a rare condition. This case report described a 16 years old male presented to the Orthodontic Department at Aberdeen Dental Hospital U.K. with a congenitally absent maxillary right central incisor in association with the congenital absence of both maxillary lateral incisors. Multidisciplinary...

To determine the prevalence and factors associated with hypotonia. Systematic review and meta-analysis. A search strategy was developed along with inclusion criteria and run in MEDLINE and EMBASE (published from 2002 to August 2012) databases to reveal all studies on the prevalence of hypodontia or associated factors. A hand search of reference lis...

Assessment of tooth morphology is an important part of the diagnosis and management of hypodontia patients. Several techniques have been used to analyze tooth form in hypodontia patients and these have shown smaller tooth dimensions and anomalous tooth shapes in patients with hypodontia when compared with controls. However, previous studies have ma...

The purpose of the present study was to investigate factors affecting the formation, severity and location of white spot lesions in patients completing fixed appliance therapy. A total of 45 patients (19 males and 26 females, mean age 15.81 years, standard deviation 2.89 years) attending consecutively Aberdeen Dental Hospital (ADH) between January...

To investigate the static frictional resistance at the bracket/archwire interface in two recently introduced bracket systems and compare them to conventional ceramic and conventional metal bracket systems. Three variables were considered including the bracket system, archwire type and archwire angulation. Four bracket systems were tested in vitro:...

Objective: Assessment of tooth morphology is essential in the diagnosis and management of hypodontia patients. Several techniques have been used to quantify tooth shape in hypodontia patients and these have shown smaller tooth dimensions and anomalous tooth shapes in these patients when compared with controls. However, previous studies have mainly...

Objective: Accurate quantification of variation in tooth shape is important in hypodontia patients. Several techniques have been used to quantify tooth size and shape in hypodontia patients and have shown smaller tooth dimensions and anomalous tooth shapes in those patients when compared with controls. However, previous studies have mainly used 2D...

As part of ongoing studies of the aetiology of dental anomalies the aims of this study were to identify multiple components of tooth size of the upper permanent incisors in 34 patients with supernumerary teeth and to compare them with those in a control group to determine whether the presence of a supernumerary tooth has a local effect on the size...

The aim of this study was to compare the dental arch sizes in a group of oligodontia patients with a group of age- and sex-matched untreated Class I control patients. Dental casts were measured of 50 oligodontia patients and 50 untreated Class I patients between 8 and 16 years old. For each subject, dental arch length and width parameters were meas...

Fluctuating dental asymmetry as an indication of the effect of environmental insults during tooth development requires further investigation. The aim of this study was to assess asymmetry in tooth crown dimension for the increased range of parameters possible with image analysis compared to previous manual measurements. Study models of 25 male and...

The aim of this study was to compare tooth size measurements between patients with supernumerary teeth and a control group. The supernumerary group consisted of 56 subjects (21 females and 35 males) and the control group of 40 subjects (20 females and 20 males). All available permanent teeth on the dental casts were imaged and measured from both bu...

A multifactorial model based on an underlying continuous distribution of tooth size, with thresholds determining hypodontia and supernumeraries, has been proposed [1]. Our aim is to investigate this model by comparing tooth morphology of affected patients and their first degree relatives with normal controls. An image analysis system [2] was used t...