Cone-beam computed tomographic (CBCT) imaging is a valuable adjunct to endodontic practice. Among... more Cone-beam computed tomographic (CBCT) imaging is a valuable adjunct to endodontic practice. Among the endodontic applications of CBCT imaging, it aids in the diagnosis of apical periodontitis, often in cases in which there is no evidence of pathosis identified by conventional imaging. The purpose of this study was to correlate the presence of apical periodontitis of teeth evaluated with 2-dimensional periapical (PA) radiographs and 3-dimensional CBCT volumes with clinical signs and symptoms. Clinical records were reviewed from patients examined at the graduate endodontics clinic. The examination included clinical examination, sensibility tests, PA radiographs, and limited field-of-view CBCT scans. Of 498 cases, 67 fulfilled the inclusion criteria and were evaluated for apical periodontitis and symptomology. CBCT slices and PA radiographs were evaluated by 2 board-certified endodontists and a board-certified oral and maxillofacial radiologist for the presence of apical periodontitis. Thirty eight of 67 teeth showed the presence of apical radiolucencies on PA radiographs and on CBCT imaging, whereas 14 teeth had no evidence of apical radiolucencies on either imaging modality. Fifteen cases showed the presence of apical radiolucencies visible on CBCT imaging that were not visible on PA radiographic images. The presence of apical radiolucencies on CBCT slices and PA radiographic images was correlated with clinical signs and symptoms, including the chief complaint. This research has important implications to prevent overexposure to radiation and to provide treatment for those patients with persistent symptoms lacking proper diagnosis based on conventional (2D) radiographs.
Part 2 of this prospective clinical study aimed to compare the one-year outcome of root canal ret... more Part 2 of this prospective clinical study aimed to compare the one-year outcome of root canal retreatments, when individual roots and teeth were assessed by periapical radiographs and CBCT. Subjects participating in this study had been referred for management of an endodontic problem associated with one or more root filled teeth. Root canal retreatment was performed by Specialists or postgraduate students under the direct supervision of Specialist endodontic staff. A total of 98 teeth (84 patients) were reassessed clinically and radiographically one year after completion of root canal retreatment. The post operative periapical radiographs and CBCT scans were compared with their respective pre-treatment (diagnostic) periapical radiographs and CBCT scans. The increase or decrease in size of existing periapical radiolucencies and development of new radiolucencies were assessed by a consensus panel consisting of two calibrated examiners. They also determined an appropriate management pl...
Objectives: Assessing the efficacy of calcium silicate cement (Biodentine™) vs. glass ionomer cem... more Objectives: Assessing the efficacy of calcium silicate cement (Biodentine™) vs. glass ionomer cement (GIC, control) as indirect pulp-capping materials in patients suffering reversible pulpitis; comparing effectiveness of cone beam computed tomography (CBCT) vs. radiographs in detecting / monitoring peri-radicular lesion change, T0 and T12 months post-operatively. Methods: 66 restorations (33 Biodentine™, 33 Fuji IX™) were allocated randomly to 53 patients. CBCT / periapical (PA) radiographs were taken at T0 and 12 months. 2 calibrated examiners assessed presence / absence and increase / decrease in size of existing PA radiolucencies under standardised conditions. Kappa coefficient evaluated statistically the effectiveness of CBCT vs. radiographs in detecting PA changes. Chi-square / Mann Whitney tests evaluated associations between PA changes in CBCT with various measures (age, vitality, symptom severity, cavity size, material, p=0.05). Results: Success rates for both Biodentine™ an...
Patel S, Dawood A, Pitt Ford T, Whaites E. The potential applications of cone beam computed tomog... more Patel S, Dawood A, Pitt Ford T, Whaites E. The potential applications of cone beam computed tomography in the management of endodontic problems. International Endodontic Journal, 40, 818-830, 2007.
We investigated the root canal configuration of maxillary premolars in a Spanish population by us... more We investigated the root canal configuration of maxillary premolars in a Spanish population by using cone-beam computed tomography. Images of 804 maxillary first and second premolars were obtained from 620 patients who underwent cone-beam computed tomography scanning during preoperative assessment (before implant surgery, orthodontic treatment, dentoalveolar trauma diagnosis, or difficult root canal treatment). We determined tooth position, number of roots, root canal configuration (Vertucci's classification), number of root canals, and number of apical foramina per root and used the χ(2) test to analyze the correlation between root number and tooth position. In the maxillary first premolar group (n = 430), 46% (n = 198) had 1 root, 51.4% (n = 221) had 2 roots, and 2.6% (n = 11) had 3 roots. Most exhibited a type IV canal configuration (n = 227, 52.8%). Single-rooted teeth had a more variable canal configuration, whereas most 2-rooted teeth showed a type IV configuration (n = 215, 97.3%). In the maxillary second premolar group (n = 374), 82.9% (n = 310) had 1 root, 15.5% (n = 58) had 2 roots, and 1.6% (n = 6) had 3 roots. The majority of single-rooted second premolars exhibited a type I configuration (n = 147, 47.2%). Overall, type VIII canals were only observed in 3-rooted teeth. No statistical correlation was evident between root number and gender and tooth position. There was a high frequency of 2-rooted and single-rooted teeth among maxillary first and second premolars, respectively. The canal morphology of single-rooted teeth was highly variable.
Although the pathogenesis and etiology of external cervical resorption (ECR) are not well underst... more Although the pathogenesis and etiology of external cervical resorption (ECR) are not well understood, several predisposing factors have been reported to potentially contribute toward the initiation of ECR. However, a potential link between systemic medication and ECR has not been reported. Bisphosphonates (BSPs) are 1 group of these medications (the amino-containing BSP), which are associated with an acute-phase response and the release of proinflammatory cytokines, which could be associated with the initiation of ECR. Therefore, a possible causal link between BSPs and ECR could be drawn.
The purpose of this study was to determine whether there is a difference in the in vivo diagnosti... more The purpose of this study was to determine whether there is a difference in the in vivo diagnostic accuracy of digital radiography (DR) and cone-beam computed tomography (CBCT) imaging in the detection of vertical root fracture (VRF). The presence/absence of VRF was confirmed by visual inspection of the extracted root surface and was the reference standard against which both imaging modalities were compared. Twenty-one unsalvageable teeth from 20 patients that had been radiographed and scanned with CBCT imaging were included in the study. The teeth were atraumatically extracted and visually inspected under a microscope to confirm the presence/absence of fracture. The widest point of each fracture was recorded using an optical coherence tomography scanner in order to quantify the size of fractures. Images were viewed under standardized conditions by 13 examiners and repeated 2 weeks later to assess their consistency. DR and CBCT imaging showed similarly poor sensitivity of 0.16 and 0...
To clinically assess the diagnostic yield from single parallel periapical, two parallax radiograp... more To clinically assess the diagnostic yield from single parallel periapical, two parallax radiographs and cone beam computed tomography (CBCT) by comparing the prevalence of periapical lesions associated with individual roots, and the total number of root canals in root-treated teeth in patients referred for root canal retreatment. Single and parallax periapical radiographs, and CBCT scans, were taken of 100 teeth in 78 patients who had been referred for root canal retreatment. The presence of a periapical lesion associated with each specific root and the number of identifiable root canals were assessed using each imaging modality by a consensus panel of two examiners. The number of root canals was confirmed using the dental-operating microscope during treatment. In addition, the panel was asked to decide whether they felt they had adequate information to manage each case. A total of 209 paired roots were assessed for periapical lesions. Lesions were identified in 41%, 38% and 68% of ...
Cone beam computed tomography (CBCT) is an extra-oral imaging system which produces 3-dimensional... more Cone beam computed tomography (CBCT) is an extra-oral imaging system which produces 3-dimensional scans of the maxillofacial skeleton. It is useful in overcoming the limitations of conventional radiography. CBCT is a valuable aid in providing additional information for diagnosis and enabling more predictable management of complex endodontic problems compared to using intra-oral radiographs alone. There are potential indications for the use of CBCT in diagnosis and treatment planning.
External cervical resorption (ECR) is the loss of dental hard tissue as a result of odontoclastic... more External cervical resorption (ECR) is the loss of dental hard tissue as a result of odontoclastic action; it usually begins on the cervical region of the root surface of the teeth. The etiology, predisposing factors, diagnosis, and management of ECR are reviewed. Effective management and appropriate treatment can only be carried out if the true nature and exact location of the ECR lesion are known. The role of cone beam computed tomography as a diagnostic adjunct for the management of ECR is also reviewed. (J Endod 2009;35:616-625)
Resorption of teeth is reviewed from a diagnostic perspective to clarify the confusion as to whet... more Resorption of teeth is reviewed from a diagnostic perspective to clarify the confusion as to whether it is external or internal. The key features of the various types (external surface, transient apical breakdown, external inflammatory, external replacement, external cervical and internal) are described and illustrated by cases. Management and appropriate treatment is dependent on the correct diagnosis. Diagnosis of resorption is essential to the appropriate management.
Niazi SA, Al-Ali WM, Patel S, Foschi F, Mannocci F. Synergistic effect of 2% chlorhexidine combin... more Niazi SA, Al-Ali WM, Patel S, Foschi F, Mannocci F. Synergistic effect of 2% chlorhexidine combined with proteolytic enzymes on biofilm disruption and killing.
Introduction: The purpose of this study was to compare the prevalence of apical periodontitis (AP... more Introduction: The purpose of this study was to compare the prevalence of apical periodontitis (AP) on individual roots of teeth with irreversible pulpitis viewed with periapical (PA) radiographs and cone-beam computed tomography (CBCT) scans. Methods: PA radiographs and CBCT scans were taken of 138 teeth in 130 patients diagnosed with irreversible pulpitis (symptomatic and asymptomatic). Two calibrated examiners assessed the presence or absence of AP lesions by analyzing the PA and CBCT images. A consensus was reached in the event of any disagreement. The data were analyzed using the hypothesis test, and significance was set at P # .05. Results: Three hundred seven paired roots were assessed with both PA and CBCT images. A comparison of the 307 paired roots revealed that AP lesions were present in 10 (3.3%) and absent in 297 (96.7%) pairs of roots when assessed with PA radiography. When the same 307 sets of roots were assessed with CBCT scans, AP lesions were present in 42 (13.7%) and absent in 265 (86.3%) paired roots. The prevalence of AP lesions detected with CBCT was significantly higher in the symptomatic group compared with the asymptomatic group (P < .05). An additional 22 roots were identified with CBCT alone. Conclusions: The present study highlights the advantages of using CBCT for detecting AP lesions, especially in teeth with symptomatic irreversible pulpitis. (J Endod 2012;38:1588-1591
Introduction: This study aimed to investigate in an ex vivo model the reduction in patient radiat... more Introduction: This study aimed to investigate in an ex vivo model the reduction in patient radiation dose while maintaining accurate linear measurements by comparing cone-beam computed tomography (CBCT) scans taken at 360 versus 180 rotation, with porcine jaw specimens as a reference standard. Methods: CBCT scans of 12 sectioned porcine hemimandibles at 360 and 180 rotations were taken with standardized clinical exposure parameters. To assess interobserver variability, 6 assessors who were blinded to the degree of rotation took linear measurements of anatomic structures on each scan. The measurements were repeated after 2 weeks to assess intraobserver variability. Accuracy of measurement was judged against the corresponding measurements taken from the porcine jaw specimens. Results: Intraclass correlations signaled good-toexcellent intraobserver and interobserver agreement (0.65-0.98 and 0.79-0.98), respectively. Mixed regression analysis found no significant difference between the measurements from 180 or 360 rotations and no difference between the 2 rotations and porcine jaw specimens. Conclusions: A CBCT image sufficient to make accurate clinical measurements with a reduced radiation exposure may be obtained by using 180 rotation of the CBCT tube head. (J Endod 2013;39:394-397)
The purpose of this study was to determine the effect of alteration of the exposure parameters of... more The purpose of this study was to determine the effect of alteration of the exposure parameters of a cone-beam computed tomographic (CBCT) scan on the detection of the presence or absence of simulated horizontal root fractures (HRFs). CBCT scans of the lower incisor region of 5 human, dentate, dry mandibles were performed with 11 different exposure parameters. Ten teeth were extracted, and simulated HRFs were created near the apical thirds of the root. The fragments were reattached and the teeth replanted. The mandibles were rescanned over the same range of exposure parameters. Receiver operator characteristic analysis and kappa analyses were performed to assess diagnostic accuracy and intra- and interexaminer agreement for each scan setting. The overall Az value (area under receiver operator curve) for the manufacturer's default setting was 0.95. The sensitivity was 0.94 and the specificity 0.96. A reduction in the tube current to 2 mA at 360° or 180° of rotation had no signific...
Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine, 2010
This is an explanatory article introducing the combination of various technologies used in implan... more This is an explanatory article introducing the combination of various technologies used in implant and restorative dentistry. The aim of the article is to provide an overview of some of the techniques supporting the restorative treatment plan at various stages to provide contemporary, state-of-the-art bridgework based on dental implants. It is a discussion of the way existing technologies used in fields of engineering and medicine are brought together to form a complete process.
Internal root resorption is the progressive destruction of intraradicular dentin and dentinal tub... more Internal root resorption is the progressive destruction of intraradicular dentin and dentinal tubules along the middle and apical thirds of the canal walls as a result of clastic activities. The prevalence, etiology, pathogenesis, histologic manifestations, differential diagnosis with cone beam computed tomography, and treatment perspectives involved in internal root resorption are reviewed. The majority of the documentation that exists in the literature is in the form of case reports, and there are only a limited number of studies that attempted to examine the histologic manifestations and biologic aspects of the disease. This might be due, in part, to the relatively rare occurrence of this type of resorption and the lack of an in vivo model, apart from the previous attempt on the use of diathermy, to predictably reproduce the condition for study. From a histologic perspective, internal root resorption is manifested in one form that is purely destructive, internal (root canal) inflammatory resorption, and another that is accompanied by repair, internal (root canal) replacement resorption that is featured by the deposition of metaplastic bone/cementum-like tissues adjacent to the sites of resorption. From a differential diagnosis perspective, the advent of cone beam computed tomography has considerably enhanced the clinician&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s capability of diagnosing internal root resorption. Nevertheless, root canal treatment remains the treatment of choice for this pathologic condition to date.
Cone-beam computed tomographic (CBCT) imaging is a valuable adjunct to endodontic practice. Among... more Cone-beam computed tomographic (CBCT) imaging is a valuable adjunct to endodontic practice. Among the endodontic applications of CBCT imaging, it aids in the diagnosis of apical periodontitis, often in cases in which there is no evidence of pathosis identified by conventional imaging. The purpose of this study was to correlate the presence of apical periodontitis of teeth evaluated with 2-dimensional periapical (PA) radiographs and 3-dimensional CBCT volumes with clinical signs and symptoms. Clinical records were reviewed from patients examined at the graduate endodontics clinic. The examination included clinical examination, sensibility tests, PA radiographs, and limited field-of-view CBCT scans. Of 498 cases, 67 fulfilled the inclusion criteria and were evaluated for apical periodontitis and symptomology. CBCT slices and PA radiographs were evaluated by 2 board-certified endodontists and a board-certified oral and maxillofacial radiologist for the presence of apical periodontitis. Thirty eight of 67 teeth showed the presence of apical radiolucencies on PA radiographs and on CBCT imaging, whereas 14 teeth had no evidence of apical radiolucencies on either imaging modality. Fifteen cases showed the presence of apical radiolucencies visible on CBCT imaging that were not visible on PA radiographic images. The presence of apical radiolucencies on CBCT slices and PA radiographic images was correlated with clinical signs and symptoms, including the chief complaint. This research has important implications to prevent overexposure to radiation and to provide treatment for those patients with persistent symptoms lacking proper diagnosis based on conventional (2D) radiographs.
Part 2 of this prospective clinical study aimed to compare the one-year outcome of root canal ret... more Part 2 of this prospective clinical study aimed to compare the one-year outcome of root canal retreatments, when individual roots and teeth were assessed by periapical radiographs and CBCT. Subjects participating in this study had been referred for management of an endodontic problem associated with one or more root filled teeth. Root canal retreatment was performed by Specialists or postgraduate students under the direct supervision of Specialist endodontic staff. A total of 98 teeth (84 patients) were reassessed clinically and radiographically one year after completion of root canal retreatment. The post operative periapical radiographs and CBCT scans were compared with their respective pre-treatment (diagnostic) periapical radiographs and CBCT scans. The increase or decrease in size of existing periapical radiolucencies and development of new radiolucencies were assessed by a consensus panel consisting of two calibrated examiners. They also determined an appropriate management pl...
Objectives: Assessing the efficacy of calcium silicate cement (Biodentine™) vs. glass ionomer cem... more Objectives: Assessing the efficacy of calcium silicate cement (Biodentine™) vs. glass ionomer cement (GIC, control) as indirect pulp-capping materials in patients suffering reversible pulpitis; comparing effectiveness of cone beam computed tomography (CBCT) vs. radiographs in detecting / monitoring peri-radicular lesion change, T0 and T12 months post-operatively. Methods: 66 restorations (33 Biodentine™, 33 Fuji IX™) were allocated randomly to 53 patients. CBCT / periapical (PA) radiographs were taken at T0 and 12 months. 2 calibrated examiners assessed presence / absence and increase / decrease in size of existing PA radiolucencies under standardised conditions. Kappa coefficient evaluated statistically the effectiveness of CBCT vs. radiographs in detecting PA changes. Chi-square / Mann Whitney tests evaluated associations between PA changes in CBCT with various measures (age, vitality, symptom severity, cavity size, material, p=0.05). Results: Success rates for both Biodentine™ an...
Patel S, Dawood A, Pitt Ford T, Whaites E. The potential applications of cone beam computed tomog... more Patel S, Dawood A, Pitt Ford T, Whaites E. The potential applications of cone beam computed tomography in the management of endodontic problems. International Endodontic Journal, 40, 818-830, 2007.
We investigated the root canal configuration of maxillary premolars in a Spanish population by us... more We investigated the root canal configuration of maxillary premolars in a Spanish population by using cone-beam computed tomography. Images of 804 maxillary first and second premolars were obtained from 620 patients who underwent cone-beam computed tomography scanning during preoperative assessment (before implant surgery, orthodontic treatment, dentoalveolar trauma diagnosis, or difficult root canal treatment). We determined tooth position, number of roots, root canal configuration (Vertucci&amp;amp;amp;amp;amp;amp;#39;s classification), number of root canals, and number of apical foramina per root and used the χ(2) test to analyze the correlation between root number and tooth position. In the maxillary first premolar group (n = 430), 46% (n = 198) had 1 root, 51.4% (n = 221) had 2 roots, and 2.6% (n = 11) had 3 roots. Most exhibited a type IV canal configuration (n = 227, 52.8%). Single-rooted teeth had a more variable canal configuration, whereas most 2-rooted teeth showed a type IV configuration (n = 215, 97.3%). In the maxillary second premolar group (n = 374), 82.9% (n = 310) had 1 root, 15.5% (n = 58) had 2 roots, and 1.6% (n = 6) had 3 roots. The majority of single-rooted second premolars exhibited a type I configuration (n = 147, 47.2%). Overall, type VIII canals were only observed in 3-rooted teeth. No statistical correlation was evident between root number and gender and tooth position. There was a high frequency of 2-rooted and single-rooted teeth among maxillary first and second premolars, respectively. The canal morphology of single-rooted teeth was highly variable.
Although the pathogenesis and etiology of external cervical resorption (ECR) are not well underst... more Although the pathogenesis and etiology of external cervical resorption (ECR) are not well understood, several predisposing factors have been reported to potentially contribute toward the initiation of ECR. However, a potential link between systemic medication and ECR has not been reported. Bisphosphonates (BSPs) are 1 group of these medications (the amino-containing BSP), which are associated with an acute-phase response and the release of proinflammatory cytokines, which could be associated with the initiation of ECR. Therefore, a possible causal link between BSPs and ECR could be drawn.
The purpose of this study was to determine whether there is a difference in the in vivo diagnosti... more The purpose of this study was to determine whether there is a difference in the in vivo diagnostic accuracy of digital radiography (DR) and cone-beam computed tomography (CBCT) imaging in the detection of vertical root fracture (VRF). The presence/absence of VRF was confirmed by visual inspection of the extracted root surface and was the reference standard against which both imaging modalities were compared. Twenty-one unsalvageable teeth from 20 patients that had been radiographed and scanned with CBCT imaging were included in the study. The teeth were atraumatically extracted and visually inspected under a microscope to confirm the presence/absence of fracture. The widest point of each fracture was recorded using an optical coherence tomography scanner in order to quantify the size of fractures. Images were viewed under standardized conditions by 13 examiners and repeated 2 weeks later to assess their consistency. DR and CBCT imaging showed similarly poor sensitivity of 0.16 and 0...
To clinically assess the diagnostic yield from single parallel periapical, two parallax radiograp... more To clinically assess the diagnostic yield from single parallel periapical, two parallax radiographs and cone beam computed tomography (CBCT) by comparing the prevalence of periapical lesions associated with individual roots, and the total number of root canals in root-treated teeth in patients referred for root canal retreatment. Single and parallax periapical radiographs, and CBCT scans, were taken of 100 teeth in 78 patients who had been referred for root canal retreatment. The presence of a periapical lesion associated with each specific root and the number of identifiable root canals were assessed using each imaging modality by a consensus panel of two examiners. The number of root canals was confirmed using the dental-operating microscope during treatment. In addition, the panel was asked to decide whether they felt they had adequate information to manage each case. A total of 209 paired roots were assessed for periapical lesions. Lesions were identified in 41%, 38% and 68% of ...
Cone beam computed tomography (CBCT) is an extra-oral imaging system which produces 3-dimensional... more Cone beam computed tomography (CBCT) is an extra-oral imaging system which produces 3-dimensional scans of the maxillofacial skeleton. It is useful in overcoming the limitations of conventional radiography. CBCT is a valuable aid in providing additional information for diagnosis and enabling more predictable management of complex endodontic problems compared to using intra-oral radiographs alone. There are potential indications for the use of CBCT in diagnosis and treatment planning.
External cervical resorption (ECR) is the loss of dental hard tissue as a result of odontoclastic... more External cervical resorption (ECR) is the loss of dental hard tissue as a result of odontoclastic action; it usually begins on the cervical region of the root surface of the teeth. The etiology, predisposing factors, diagnosis, and management of ECR are reviewed. Effective management and appropriate treatment can only be carried out if the true nature and exact location of the ECR lesion are known. The role of cone beam computed tomography as a diagnostic adjunct for the management of ECR is also reviewed. (J Endod 2009;35:616-625)
Resorption of teeth is reviewed from a diagnostic perspective to clarify the confusion as to whet... more Resorption of teeth is reviewed from a diagnostic perspective to clarify the confusion as to whether it is external or internal. The key features of the various types (external surface, transient apical breakdown, external inflammatory, external replacement, external cervical and internal) are described and illustrated by cases. Management and appropriate treatment is dependent on the correct diagnosis. Diagnosis of resorption is essential to the appropriate management.
Niazi SA, Al-Ali WM, Patel S, Foschi F, Mannocci F. Synergistic effect of 2% chlorhexidine combin... more Niazi SA, Al-Ali WM, Patel S, Foschi F, Mannocci F. Synergistic effect of 2% chlorhexidine combined with proteolytic enzymes on biofilm disruption and killing.
Introduction: The purpose of this study was to compare the prevalence of apical periodontitis (AP... more Introduction: The purpose of this study was to compare the prevalence of apical periodontitis (AP) on individual roots of teeth with irreversible pulpitis viewed with periapical (PA) radiographs and cone-beam computed tomography (CBCT) scans. Methods: PA radiographs and CBCT scans were taken of 138 teeth in 130 patients diagnosed with irreversible pulpitis (symptomatic and asymptomatic). Two calibrated examiners assessed the presence or absence of AP lesions by analyzing the PA and CBCT images. A consensus was reached in the event of any disagreement. The data were analyzed using the hypothesis test, and significance was set at P # .05. Results: Three hundred seven paired roots were assessed with both PA and CBCT images. A comparison of the 307 paired roots revealed that AP lesions were present in 10 (3.3%) and absent in 297 (96.7%) pairs of roots when assessed with PA radiography. When the same 307 sets of roots were assessed with CBCT scans, AP lesions were present in 42 (13.7%) and absent in 265 (86.3%) paired roots. The prevalence of AP lesions detected with CBCT was significantly higher in the symptomatic group compared with the asymptomatic group (P < .05). An additional 22 roots were identified with CBCT alone. Conclusions: The present study highlights the advantages of using CBCT for detecting AP lesions, especially in teeth with symptomatic irreversible pulpitis. (J Endod 2012;38:1588-1591
Introduction: This study aimed to investigate in an ex vivo model the reduction in patient radiat... more Introduction: This study aimed to investigate in an ex vivo model the reduction in patient radiation dose while maintaining accurate linear measurements by comparing cone-beam computed tomography (CBCT) scans taken at 360 versus 180 rotation, with porcine jaw specimens as a reference standard. Methods: CBCT scans of 12 sectioned porcine hemimandibles at 360 and 180 rotations were taken with standardized clinical exposure parameters. To assess interobserver variability, 6 assessors who were blinded to the degree of rotation took linear measurements of anatomic structures on each scan. The measurements were repeated after 2 weeks to assess intraobserver variability. Accuracy of measurement was judged against the corresponding measurements taken from the porcine jaw specimens. Results: Intraclass correlations signaled good-toexcellent intraobserver and interobserver agreement (0.65-0.98 and 0.79-0.98), respectively. Mixed regression analysis found no significant difference between the measurements from 180 or 360 rotations and no difference between the 2 rotations and porcine jaw specimens. Conclusions: A CBCT image sufficient to make accurate clinical measurements with a reduced radiation exposure may be obtained by using 180 rotation of the CBCT tube head. (J Endod 2013;39:394-397)
The purpose of this study was to determine the effect of alteration of the exposure parameters of... more The purpose of this study was to determine the effect of alteration of the exposure parameters of a cone-beam computed tomographic (CBCT) scan on the detection of the presence or absence of simulated horizontal root fractures (HRFs). CBCT scans of the lower incisor region of 5 human, dentate, dry mandibles were performed with 11 different exposure parameters. Ten teeth were extracted, and simulated HRFs were created near the apical thirds of the root. The fragments were reattached and the teeth replanted. The mandibles were rescanned over the same range of exposure parameters. Receiver operator characteristic analysis and kappa analyses were performed to assess diagnostic accuracy and intra- and interexaminer agreement for each scan setting. The overall Az value (area under receiver operator curve) for the manufacturer's default setting was 0.95. The sensitivity was 0.94 and the specificity 0.96. A reduction in the tube current to 2 mA at 360° or 180° of rotation had no signific...
Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine, 2010
This is an explanatory article introducing the combination of various technologies used in implan... more This is an explanatory article introducing the combination of various technologies used in implant and restorative dentistry. The aim of the article is to provide an overview of some of the techniques supporting the restorative treatment plan at various stages to provide contemporary, state-of-the-art bridgework based on dental implants. It is a discussion of the way existing technologies used in fields of engineering and medicine are brought together to form a complete process.
Internal root resorption is the progressive destruction of intraradicular dentin and dentinal tub... more Internal root resorption is the progressive destruction of intraradicular dentin and dentinal tubules along the middle and apical thirds of the canal walls as a result of clastic activities. The prevalence, etiology, pathogenesis, histologic manifestations, differential diagnosis with cone beam computed tomography, and treatment perspectives involved in internal root resorption are reviewed. The majority of the documentation that exists in the literature is in the form of case reports, and there are only a limited number of studies that attempted to examine the histologic manifestations and biologic aspects of the disease. This might be due, in part, to the relatively rare occurrence of this type of resorption and the lack of an in vivo model, apart from the previous attempt on the use of diathermy, to predictably reproduce the condition for study. From a histologic perspective, internal root resorption is manifested in one form that is purely destructive, internal (root canal) inflammatory resorption, and another that is accompanied by repair, internal (root canal) replacement resorption that is featured by the deposition of metaplastic bone/cementum-like tissues adjacent to the sites of resorption. From a differential diagnosis perspective, the advent of cone beam computed tomography has considerably enhanced the clinician&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s capability of diagnosing internal root resorption. Nevertheless, root canal treatment remains the treatment of choice for this pathologic condition to date.
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