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OBJECTIVE: To compare the dosimetry between convex triangular fields of view (FOV) and similar dimension cylindrical FOVs of two cone-beam computed tomography (CBCT) models. METHODS: Optically stimulated luminescence dosimeters (OSLDs) were placed in fiducial anatomical locations in an anthropomorphic phantom representing an adult head male for dosimetry scans. Convex triangular FOVs (100 × 80 mm/maxilla-mandible; 100 × 50 mm mandible; 100 × 50 mm/maxilla) from Veraviewepocs 3D R100 (J. Morita, Kyoto, Japan) (R100) and Veraview® X800 (J. Morita, Kyoto, Japan) (X800) and cylindrical FOVs from R100 and X800 (80 × 80 mm/maxilla-mandible; 80 × 50 mm/mandible; 80 × 50 mm/maxilla) were obtained, resulting in 12 different scan protocols. Equivalent doses for each relevant organ/tissue and the effective dose for each protocol were calculated. Mean effective doses were compared by the two-way analysis of variance (ANOVA) with Tukey's post hoc test to evaluate the effect of the FOV and device (α = 0.05). RESULTS: The effective doses ranged between 69 and 324 µSv for the convex triangular FOVs and 76 and 332 µSv for the cylindrical FOVs. Convex triangular FOVs from the R100 device had effective doses 2.3 to 15.3% lower than their corresponding cylindrical FOVs with similar height (p < 0.05), and that difference ranged between 8.8 and 11.8% for the X800 device (p < 0.05). CONCLUSION: Convex triangular fields of view delivered slightly lower effective doses than the cylindrical fields of view of similar dimensions in the R100 and X800 CBCT devices. CLINICAL RELEVANCE: Understanding the influence of the image geometry formation in effective dose allows optimization to reduce patient dose.
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Tomografia Computadorizada de Feixe Cônico , Radiometria , Adulto , Masculino , Humanos , Doses de Radiação , Tomografia Computadorizada de Feixe Cônico/métodos , Mandíbula/diagnóstico por imagem , Maxila , Imagens de FantasmasRESUMO
The quality of Cone Beam Computed Tomography (CBCT) images is directly influenced by scanning and visualization protocols. Evaluate the subjective quality of the Cone Beam Computed Tomography (CBCT) image of different devices and protocols for diagnosing periodontal structures and correlate the findings with the contrast-to-noise ratio (CNR). One dry dentate mandible was scanned by six CBCT devices: Accuitomo 3D 170, CS 9000, CS 9300, Eagle 3D, i-CAT Classic, and Orthophos XG 3D. All CBCT devices were adjusted to provide a spatial resolution closest to 0.2 mm, and a FOV height limited to less than 100 mm. Cross-sectional images were evaluated randomly. The buccal bone coverage, the periodontal ligament space and the amount of image noise were assessed. The statistics were calculated based on a logistic regression model with the significance level set at 5%. Protocols with large FOVs demonstrated significantly lower image quality. No statistical differences were found regarding buccal bone coverage between the CBCT devices. The CNR showed the highest value for the Accuitomo 60mm x 60mm HiFi 180°, followed by the Accuitomo 60mm x 60mm HiFi 360°, and lower values for the i-Cat Classic and Orthophos XG 3D devices. Most protocols studied presented good image quality in evaluating the buccal bone coverage and periodontal ligament space. However, the exam with the lowest FOV of the Accuitomo 60mm x 60mm HiFi 180° device showed superiority concerning the others.(AU)
A qualidade das imagens de tomografia computadorizada de feixe cônico (CBCT) é diretamente influenciada pelos protocolos de digitalização e visualização. Avaliar a qualidade subjetiva da imagem da Tomografia Computadorizada de Feixe Cone (CBCT) de diferentes aparelhos e protocolos para o diagnóstico de estruturas periodontais e correlacionar os achados com a razão contraste-ruído (RCR). Uma mandíbula dentada seca foi digitalizada por seis dispositivos CBCT: Accuitomo 3D 170, CS 9000, CS 9300, Eagle 3D, i-CAT Classic e Orthophos XG 3D. Todos os dispositivos CBCT foram ajustados para fornecer uma resolução espacial próxima a 0,2 mm e uma altura de FOV limitada a menos de 100 mm. Imagens transversais foram avaliadas aleatoriamente. A cobertura óssea vestibular, o espaço do ligamento periodontal e a quantidade de ruído da imagem foram avaliados. As estatísticas foram calculadas com base em um modelo de regressão logística com nível de significância de 5%. Protocolos com grandes FOVs demonstraram qualidade de imagem significativamente inferior. Não foram encontradas diferenças estatísticas em relação à cobertura óssea vestibular entre os dispositivos CBCT. O CNR apresentou o maior valor para o Accuitomo 60mm x 60mm HiFi 180°, seguido pelo Accuitomo 60mm x 60mm HiFi 360°, e valores menores para os dispositivos i-Cat Classic e Orthophos XG 3D. A maioria dos protocolos estudados apresentou boa qualidade de imagem na avaliação da cobertura óssea vestibular e do espaço do ligamento periodontal. Entretanto, o exame com menor FOV do aparelho Accuitomo 60mm x 60mm HiFi 180° apresentou superioridade em relação aos demais. (AU)
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This article presents a retrospective case series of implant site development using titanium mesh (Ti-mesh) in the maxilla. A total of 58 mesh procedures in combination with several different bone grafts (allograft, cellular allograft, and bovine xenograft) and biologics (including recombinant human platelet-derived growth factor, autogenous platelet-rich growth factor, and recombinant human bone morphogenetic protein-2) were performed in 48 patients. Ti-mesh guided bone regeneration procedures were performed 2 to 3 months after extraction of nonrestorable/hopeless teeth, and the implants were placed 6 to 8 months postaugmentation. The mean initial ridge width was 2.0 ± 1.0 mm, and the mean horizontal gain after Ti-mesh procedures was 4.7 ± 1.6 mm. The ridge width was first measured on the cross-sectional presurgical CBCT image and then confirmed clinically during surgical procedures. No statistical difference in the horizontal gain was found among different combinations of bone grafts and biomaterials. Ti-mesh exposure occurred 22% of the time. The middle-aged adults (odds ratio [OR] = 8.59; P = .046) and older adults (OR = 16.66; P = .02) had significantly higher chances of mesh exposure compared to young adults. While all implants were successfully placed, about 56% of the implants had < 2 mm of bone to the facial aspect of the osteotomy and received additional contour augmentation when placed in a prosthetically appropriate position for a screw-retained restoration. This study demonstrates that although Ti-mesh procedures result in significant bone regeneration in narrow alveolar ridges to predictably allow implant placement, the age-related mesh exposure rate and frequency of need for additional contour grafting should be discussed with patients.
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Aumento do Rebordo Alveolar , Implantes Dentários , Idoso , Animais , Regeneração Óssea , Transplante Ósseo , Bovinos , Estudos Transversais , Implantação Dentária Endóssea , Humanos , Maxila/diagnóstico por imagem , Maxila/cirurgia , Pessoa de Meia-Idade , Estudos Retrospectivos , Telas Cirúrgicas , Titânio , Adulto JovemRESUMO
The purpose of this prospective study was to evaluate the success rates and prosthetic complications of implants with a modified sandblasted and acid-etched (SLA) surface inserted for posterior single-implant crown restorations. Final crowns were placed 3 to 4 weeks after surgery, and patient follow-up spanned 10 years in a private practice setting. A total of 22 patients (8 women, 14 men) with 25 posterior implants placed (16 mandible, 9 maxilla) were selected, including only implants for posterior single-implant crowns with insertion torque values of ≥ 35 Ncm at placement. Twenty-one implants passed the reverse torque test at 3 to 4 weeks after implant placement, and final restorations were placed. Three patients (4 implants) had "spinners," and there was one patient dropout after completion of the final restoration. All patients were recalled for clinical exams, digital periapical radiographs, and clinical photos at short-term (≤ 5 years) and long-term (> 5 years) follow-up appointments. The Community Periodontal Index of Treatment Needs was also determined at the initial and follow-up visits. Crestal bone level was measured at crown placement (T1), short-term follow-up (T2; mean: 29.4 months), and long-term follow-up appointments (T3; mean: 114.4 months). Twenty patients (23 implants) returned for examination at T2, and 15 (18 implants) were available at T3. For the 17 implants available at all evaluations, statistically significant bone loss was found from T1 to T2 (0.23 ± 0.30 mm), and the mean crestal bone level appeared stable from T2 to T3. Based on clinical and radiographic findings, the success rate for the implants and restorations at T2 and T3 was graded as 100%. Therefore, it can be stated that an early loading protocol of 3 to 4 weeks using a modified SLA surface at premolar/molar single-tooth locations can result in favorable clinical and radiographic long-term results.
Assuntos
Perda do Osso Alveolar , Implantes Dentários , Perda do Osso Alveolar/diagnóstico por imagem , Coroas , Implantação Dentária Endóssea , Planejamento de Prótese Dentária , Prótese Dentária Fixada por Implante , Feminino , Seguimentos , Humanos , Masculino , Osseointegração , Estudos Prospectivos , TitânioRESUMO
OBJECTIVES: To investigate the frequency and reasons for retaking cone beam computed tomography (CBCT) scans in an oral and maxillofacial radiology imaging clinic in a dental institution. MATERIALS AND METHODS: A retrospective cohort chart audit of the patient image database was performed for 1737 patients attending the Diagnostic Imaging clinic at the Prince Philip Dental Hospital from February 2016 to May 2019, and the rate of, and reasons for, CBCT image re-exposure was tallied. Patient demographics (age and gender) and CBCT acquisition parameters (CBCT unit, field-of-view (FOV), scanned region of interest, and exposure time) were recorded and correlated to retake analysis. RESULTS: The retake rate was 4.6% (80/1737). The most common reasons for re-exposure were incomplete FOV coverage (57.5%) and motion artifacts (27.5%). Patients under 12 years of age had a significantly higher risk for motion artifacts. CBCT for the temporomandibular joint (TMJ) had a significantly higher risk for incomplete FOV coverage. CONCLUSIONS: Children (less than 12 years of age) demonstrate a higher frequency of retakes, principally due to motion artifacts. TMJ CBCT examinations have a higher frequency of retakes due to an incomplete FOV coverage. CLINICAL RELEVANCE: Information regarding the frequency and reasons for CBCT retakes is beneficial to identify procedures, practices, or patients susceptible to additional radiation exposure and implement appropriate and specific quality control protocols.
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Artefatos , Tomografia Computadorizada de Feixe Cônico , Criança , Humanos , Imagens de Fantasmas , Estudos Retrospectivos , Articulação TemporomandibularRESUMO
BACKGROUND: The authors conducted a survey of the American Academy of Pediatric Dentistry (AAPD) to determine awareness of the Image Gently Campaign in Dentistry (IGCD) and to ascertain radiologic practices, including radiation dose-reduction strategies such as rectangular collimation. METHODS: An institutional review board approved an electronic survey sent to 7,087 AAPD members covering practitioner demographic characteristics, radiographic techniques, and dose-reduction practices, including rectangular collimation. Responses were tabulated and analyzed using binomial tests, χ2 tests, and Fisher exact tests. RESULTS: A total of 1,124 pediatric dentists or residents in pediatric dentistry responded, (response rate 16%, margin of error ± 2.7%). The largest group (23.8%) graduated after 2010. More than 90% indicated that they followed American Dental Association (ADA)-AAPD radiation exposure guidelines, but only 33.5% were aware of IGCD. Almost all respondents used direct digital systems, storage phosphor plates, or both. Only 22.3% (n = 220) used rectangular collimation. Nonusers indicated that they were unfamiliar with collimation (33.3%) or concerned about potential for increased cone cuts (30.2%), 11.6% of respondents were unaware of any regulatory requirements for inspections of radiographic equipment recurring at regular intervals, and 4.1% of respondents considered use of lead aprons optional. CONCLUSIONS: Although the pediatric dentists surveyed believe they are in compliance with ADA-AAPD guidelines, most are unaware of IGCD recommendations. Use of digital radiography is almost ubiquitous, but use of rectangular collimation is limited. PRACTICE IMPLICATIONS: Dentists treating children should be familiar with ADA-AAPD radiation exposure guidelines and should consider using the dose-reduction strategies recommended by IGCD.
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Exposição à Radiação , Radiografia Dentária Digital , Criança , Odontólogos , Humanos , Doses de Radiação , Inquéritos e Questionários , Estados UnidosRESUMO
This case series describes a reconstruction method applied to a cone beam computed tomography (CBCT) projection data set that used selected basis projection images to improve diagnostic image quality for patients who moved during the radiographic procedure. Reconstructed volumetric data from 6 patients at 2 institutions initially exhibited characteristic double contour images as a result of motion artifacts. For each case, the CBCT basis images from the entire projection data set were displayed as a cine sequence, and patient movement was identified during the first or last 90-degrees of a full 360-degree acquisition trajectory. Employing a useful reconstruction function of proprietary software, a secondary reconstruction was performed by discarding data acquired during the first and last 90-degree rotation. For all cases, this method provided a volumetric data set without motion artifact. General practitioners can apply this clinical method, whenever appropriate, to avoid a rescan and keep patient exposure "as low as diagnostically acceptable."
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Artefatos , Tomografia Computadorizada de Feixe Cônico , Algoritmos , Humanos , Processamento de Imagem Assistida por Computador , Movimento , Imagens de FantasmasRESUMO
OBJECTIVES: Working Group 5 was assigned the task to review the current knowledge in the area of digital technologies. Focused questions on accuracy of linear measurements when using CBCT, digital vs. conventional implant planning, using digital vs. conventional impressions and assessing the accuracy of static computer-aided implant surgery (s-CAIS) and patient-related outcome measurements when using s-CAIS were addressed. MATERIALS AND METHODS: The literature was systematically searched, and in total, 232 articles were selected and critically reviewed following PRISMA guidelines. Four systematic reviews were produced in the four subject areas and amply discussed in the group. After emendation, they were presented to the plenary where after further modification, they were accepted. RESULTS: Static computer-aided surgery (s-CAIS), in terms of pain & discomfort, economics and intraoperative complications, is beneficial compared with conventional implant surgery. When using s-CAIS in partially edentulous cases, a higher level of accuracy can be achieved when compared to fully edentulous cases. When using an intraoral scanner in edentulous cases, the results are dependent on the protocol that has been followed. The accuracy of measurements on CBCT scans is software dependent. CONCLUSIONS: Because the precision intraoral scans and of measurements on CBCT scans and is not high enough to allow for the required accuracy, s-CAIS should be considered as an additional tool for comprehensive diagnosis, treatment planning, and surgical procedures. Flapless s-CAIS can lead to implant placement outside of the zone of keratinized mucosa and thus must be executed with utmost care.
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Desenho Assistido por Computador , Tomografia Computadorizada de Feixe Cônico/métodos , Imageamento Tridimensional/métodos , Cirurgia Assistida por Computador/métodos , Consenso , Bases de Dados Factuais , Implantação Dentária Endóssea , Técnica de Moldagem Odontológica , Prótese Dentária Fixada por Implante , Humanos , Boca Edêntula/cirurgia , Planejamento de Assistência ao Paciente , Medidas de Resultados Relatados pelo Paciente , Reprodutibilidade dos Testes , SoftwareRESUMO
OBJECTIVE: The aim of this systematic review was to identify, review, analyze, and summarize available evidence on the accuracy of linear measurements when using maxillofacial cone beam computed tomography (CBCT) specifically in the field of implant dentistry. MATERIAL AND METHODS: The search was undertaken in April 2017 in the National Library of Medicine database (Medline) through its online site (PubMed), followed by searches in the Cochrane, EMBASE, ScienceDirect, and ProQuest Dissertation and Thesis databases. The main inclusion criterion for studies was that linear CBCT measurements were performed for quantitative assessment (e.g., height, width) of the alveolar bone at edentulous sites or measuring distances from anatomical structures related to implant dentistry. The studies should compare these values to clinical data (humans) or ex vivo and/or experimental (animal) findings from a "gold standard." RESULTS: The initial search yielded 2,516 titles. In total, 22 studies were included in the final analysis. Of those, two were clinical and 20 ex vivo investigations. The major findings of the review indicate that CBCT provides cross-sectional images that demonstrate high accuracy and reliability for bony linear measurements on cross-sectional images related to implant treatment. A wide range of error has been reported when performing linear measurements on CBCT images, with both over- and underestimation of dimensions in comparison with a gold standard. A voxel size of 0.3 to 0.4 mm is adequate to provide CBCT images of acceptable diagnostic quality for implant treatment planning. CONCLUSIONS: CBCT can be considered as an appropriate diagnostic tool for 3D preoperative planning. Nevertheless, a 2 mm safety margin to adjacent anatomic structures should be considered when using CBCT. In clinical practice, the measurement accuracy and reliability of linear measurements on CBCT images are most likely reduced through factors such as patient motion, metallic artefacts, device-specific exposure parameters, the software used, and manual vs. automated procedures.
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Tomografia Computadorizada de Feixe Cônico/métodos , Implantação Dentária Endóssea , Implantes Dentários , Planejamento de Assistência ao Paciente , Processo Alveolar/anatomia & histologia , Processo Alveolar/diagnóstico por imagem , Processo Alveolar/cirurgia , Animais , Bases de Dados Factuais , Ossos Faciais/anatomia & histologia , Ossos Faciais/diagnóstico por imagem , Ossos Faciais/cirurgia , Humanos , Mandíbula/anatomia & histologia , Mandíbula/diagnóstico por imagem , Mandíbula/cirurgia , Maxila/anatomia & histologia , Maxila/diagnóstico por imagem , Maxila/cirurgia , Reprodutibilidade dos Testes , SoftwareRESUMO
INTRODUCTION: We aimed to investigate the incidence and severity of orthodontically induced inflammatory root resorption (OIIRR) on maxillary incisors with clear aligner therapy using cone-beam computed tomography and to identify possible risk factors. METHODS: The root lengths of maxillary incisors were measured on orthogonal images from pretreatment and posttreatment cone-beam computed tomography examinations of 160 patients who received comprehensive orthodontic treatment with clear aligners. RESULTS: Mean absolute reductions in root length varied between 0.47 ± 0.61 mm and 0.55 ± 0.70 mm and were not significantly different between maxillary central and lateral incisors. The prevalence of severe OIIRR, defined as both maxillary central incisors experiencing greater than a 25% reduction in root length, was found to be 1.25%. Potential risk factors included sex, malocclusion, crowding, and posttreatment approximation of apices to the cortical plates. Race, interproximal reduction, previous trauma to the teeth, elastics, age, treatment duration, and pretreatment approximation of apices to the cortical plates did not significantly affect the amount of OIIRR. CONCLUSIONS: Comprehensive treatment with clear aligners resulted in minimal root resorption. Sex, malocclusion, crowding, and posttreatment approximation to the cortical plates significantly affected the percentage of change in root length. Posttreatment approximation of root apices to the palatal cortical plate showed the strongest association for increased OIIRR.
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Tomografia Computadorizada de Feixe Cônico , Aparelhos Ortodônticos/efeitos adversos , Ortodontia Corretiva/efeitos adversos , Reabsorção da Raiz/diagnóstico por imagem , Reabsorção da Raiz/etiologia , Adulto , Feminino , Humanos , Incidência , Incisivo , Masculino , Maxila , Desenho de Aparelho Ortodôntico , Estudos Retrospectivos , Fatores de Risco , Reabsorção da Raiz/epidemiologiaRESUMO
OBJECTIVE: The objective of the study was to compare estimates of pediatric cumulative exposure and lifetime attributable risk (LAR) of radiation-induced cancer from dental radiology between cleft palate (CP) subjects and age- and gender-matched controls (non-CP), with and without orthodontic treatment. MATERIALS AND METHODS: The radiation exposure frequency of CP subjects and non-CP controls with and without orthodontic treatment was compared for two-dimensional radiography (intra-oral, panoramic and cephalometric radiography), computed tomography (CT), and cone-beam CT (CBCT) using cumulative radiation dose as an estimate. From this dose estimate, the age- and gender-dependent risk for radiation-induced stochastic effects was calculated for each patient group. RESULTS: CP patients received more radiographic examinations than non-CP controls, with the exception of intra-oral radiographs. The cumulative dose to CP patients was considerably higher (1963 µSv at the age of 20 years) than non-CP patients with (597 µSv) and without (383 µSv) orthodontic treatment, primarily due to the higher frequency of CT scanning. Accordingly, CP patients had a three to five times higher LAR than non-CP patients. CONCLUSIONS: This study suggests a significantly higher lifetime radiation exposure to CP patients than non-CP controls from dental radiographic procedures. Diagnostic benefits from the use of CT and CBCT in children must be justified and appropriate dose optimization strategies implemented. CLINICAL RELEVANCE: The present study indicates the need for proper justification and optimization of pediatric exposures in dentistry, with a special focus on high-risk groups.
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Fissura Palatina/diagnóstico por imagem , Exposição à Radiação , Radiografia Dentária , Cefalometria , Criança , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Masculino , Neoplasias Induzidas por Radiação/etiologia , Ortodontia Corretiva , Radiografia Panorâmica , Estudos Retrospectivos , Risco , Tomografia Computadorizada por Raios XRESUMO
Numerous benign cysts or solid tumors may present in the jaws. These arise from tooth-forming tissues in the dental alveolus or from nonodontogenic tissues in the basal bone of the mandible and maxilla. Radiologists provide 2 deliverables to assist in diagnosis and management: (1) appropriately formatted images demonstrating the location and extent of the lesion and (2) interpretive reports highlighting specific radiologic findings and an impression providing a radiologic differential diagnosis. This article provides guidance on essential image protocols for planning treatments, a radiologic differential diagnostic algorithm based on location and pattern recognition, and a summary of the main features of benign odontogenic lesions.
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Algoritmos , Cistos Maxilomandibulares/diagnóstico por imagem , Neoplasias Maxilomandibulares/diagnóstico por imagem , Intensificação de Imagem Radiográfica/métodos , Radiografia Dentária/métodos , Diagnóstico Diferencial , HumanosRESUMO
PURPOSE: To determine the effectiveness of cone beam computed tomography (CBCT) images obtained with different kilovoltage settings compared with intraoral periapical photostimulable storage phosphor (PSP) plate images in the detection of chemically created peri-implant defects utilizing a bovine rib bone model in vitro. MATERIALS AND METHODS: After placing 80 implants in bovine ribs, peri-implant circumferential bone defects of different sizes were created with 70% perchloric acid. CBCT images (3D Accuitomo 170) were acquired at 90 and 75 kVp, and intraoral periapical images were acquired using a PSP system (Carestream KODAK, CS 7600). Using a 5-point Likert scale, two oral and maxillofacial radiologists (OMR) and two oral and maxillofacial surgeons (OMS) evaluated the likelihood of a bone defect being absent or present. The kappa statistic was used to compare observer agreement, and area under the curve values were compared using analysis of variance and the post hoc Tukey test. Significance was set at P ≤ .05. RESULTS: PSP reliability ranged from discordance to slight for small defects and fair to moderate for larger defects. For CBCT, OMRs had good agreement for defects using 90 kVp, and slight to fair using 75 kVp. Agreement for OMS observations was fair for 75 kVp, and varied from slight to good for 90 kVp. Small lesions were detected more effectively by CBCT than by PSP, and larger lesions were detected more effectively by CBCT at 90 kVp than by CBCT at 75 kVp or by PSP. CONCLUSION: CBCT imaging at 90 kVp was associated with a significantly higher rate of detection of both small and large chemically simulated bone defects than PSP or CBCT at 75 kVp. CBCT imaging at 75 kVp proved better than PSP for the detection of small defects.
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Tomografia Computadorizada de Feixe Cônico/métodos , Processamento de Imagem Assistida por Computador/métodos , Peri-Implantite/diagnóstico por imagem , Animais , Bovinos , Humanos , Variações Dependentes do Observador , Peri-Implantite/induzido quimicamente , Radiografia Dentária , Reprodutibilidade dos Testes , Costelas/diagnóstico por imagem , Costelas/cirurgiaRESUMO
Contemporary periodontal therapy has evolved to become more interdisciplinary and increasingly involves more complex treatments, including bone and soft-tissue regenerative procedures. Therapeutic options require an imaging modality or combination of techniques that are capable of providing a diagnostic osseous baseline and facilitating quantification of smaller increments of bony change, both loss and additive, which are comparable over time. Intra-oral and panoramic radiography are the modalities most commonly used to identify the location, quantify the amount and the pattern of alveolar bone loss and determine response to therapy. Cone-beam computed tomography imaging offers specific advantages for periodontal diagnosis in that three-dimensional images of dental and alveolar bone structures can be rendered with accuracy. Cone-beam computed tomography has been shown to be clinically efficacious in demonstrating localized defects, such as furcation involvement and intrabony vertical and buccal/lingual defects, and in assessing the effects of regenerative therapy. In these situations, limited-field-of-view, high-resolution protocols are indicated.
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Tomografia Computadorizada de Feixe Cônico/métodos , Periodontite/diagnóstico por imagem , Periodontite/terapia , Radiografia Dentária Digital/métodos , Radiografia Panorâmica/métodos , Perda do Osso Alveolar/diagnóstico por imagem , Perda do Osso Alveolar/terapia , Humanos , Imageamento Tridimensional/métodos , Interpretação de Imagem Radiográfica Assistida por ComputadorRESUMO
Digital advances have changed implant planning to improve outcomes in placement and restoration. Layering multiple image inputs, such as volumetric radiology, photography, and 3-dimensional (3D) surface scans, has allowed better assessment of patients with partial or complete edentulism, and this can aid in producing 3D visual predictions, implant guides, and prosthetics to execute the proposed plan.
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Implantação Dentária/métodos , Imageamento Tridimensional/métodos , Tomografia Computadorizada de Feixe Cônico/métodos , Implantes Dentários , Humanos , Radiografia Dentária/métodosRESUMO
PURPOSE: To compare the choice and placement of virtual dental implants in the posterior edentulous bounded regions using the full cross-sectional and transaxial capabilities of cone beam computed tomography (CBCT) vs reformatted panoramic images and three-dimensional (3D) virtual models. MATERIALS AND METHODS: Fifty-two cases with posterior bounded edentulous regions (61 dental implant sites) were identified from a retrospective audit of 4,014 radiographic volumes. Two image sets were created from selected CBCT data: (1) a combination of reformatted panoramic imaging and a 3D model (PIref/3D), and (2) the full 3D power in CBCT image volume analyses (XS). One virtual implant was placed by consensus of three prosthodontists in each image set: PIref/3D and XS. The choice of implant length and the perceived need for ridge augmentation were recorded for implant placement in both test situations. All the virtual implant placements from both PIref/3D and XS image sets were inspected retrospectively using virtual 3D models, and the number of exposed threads on both the buccal and lingual/palatal aspects of the virtual dental implant was evaluated. The chi-square and paired t tests were used with the level of significance set at α = .05. RESULTS: Shorter implants were chosen more often using XS than PIref/3D (P = .001). Fewer threads were exposed when placed with XS than with PIref/3D (P = .001). The use of XS reduced the perceived need for ridge augmentation compared with PIref/3D (P = .001). CONCLUSION: The use of the full 3D power of CBCT (including cross-sectional images in all three orthagonal planes and transaxially) provides supplemental information that significantly changes the choice of virtual implant length and vertical position of the implant, and reduces the frequency of perceived need for ridge augmentation before implant placement.
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Tomografia Computadorizada de Feixe Cônico , Implantação Dentária Endóssea/métodos , Implantes Dentários , Imageamento Tridimensional/métodos , Desenho Assistido por Computador , Tomografia Computadorizada de Feixe Cônico/métodos , Estudos Transversais , Feminino , Humanos , Arcada Parcialmente Edêntula/cirurgia , Masculino , Estudos RetrospectivosRESUMO
BACKGROUND: The aim of this study is to determine the influence of field of view (FOV) and number of acquisition projection images (frames) on the detection of chemically simulated peri-implant defects by cone-beam computed tomography (CBCT) using an in vitro bovine rib bone model. METHODS: Eighty implants were placed in bovine ribs in which small and large bone defects were created using 70% perchloric acid. CBCT images were acquired at three acquisition protocols: protocol 1 (FOV 4 × 4 cm, 0.08-mm voxel size, 1,009 frames [high fidelity]; protocol 2 (same as protocol 1 except 512 frames [standard]); and protocol 3 (FOV 14 × 5 cm, 0.25-mm voxel size; high fidelity). Two oral and maxillofacial radiologists (OMRs) and two oral and maxillofacial surgeons (OMSs) rated the presence or absence of bone defects on a five-point scale. κ and area under the curve (AUC) were calculated and compared using analysis of variance with post hoc Tukey test at P ≤ 0.05. RESULTS: Intra- and interobserver agreement for OMRs ranged from moderate to good and from slight to moderate for OMSs. For the detection of small lesions, protocol 1 (AUC 0.813 ± 0.045) provided higher detection rates than protocol 2 (AUC 0.703 ± 0.02) and protocol 3 (AUC 0.773 ± 0.55) [F(2,9) = 1.6377]. For larger defects, the trends were similar, with protocol 1 (AUC 0.852 ± 0.108) providing higher detection rates than protocol 2 (AUC 0.730 ± 0.045) and protocol 3 (AUC 0.783 ± 0.058) [F(2,9) = 1.9576]. CONCLUSION: Within the limits of this study, optimal detection of chemically simulated pericircumferential implant crestal bone defects is achieved at the least radiation detriment using the smallest FOV, the highest number of acquisition frames, and the smallest voxel.
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Tomografia Computadorizada de Feixe Cônico/normas , Processamento de Imagem Assistida por Computador/normas , Peri-Implantite/diagnóstico por imagem , Animais , Área Sob a Curva , Bovinos , Implantes Dentários , Técnicas In Vitro , Variações Dependentes do Observador , Percloratos/efeitos adversos , Peri-Implantite/induzido quimicamente , Curva ROC , Distribuição Aleatória , Costelas/efeitos dos fármacosAssuntos
Redes de Comunicação de Computadores/legislação & jurisprudência , Health Insurance Portability and Accountability Act , Processamento de Imagem Assistida por Computador/métodos , Legislação Odontológica , Privacidade/legislação & jurisprudência , Compressão de Dados/métodos , Correio Eletrônico , Humanos , Internet , Radiografia Dentária , Software , Estados UnidosRESUMO
PURPOSE: To analyze available evidence on the incidence of anatomical variations or disease of the maxillary sinuses as identified by cone beam computed tomography (CBCT) in dentistry. MATERIALS AND METHODS: A focused question was developed to search the electronic databases MEDLINE, EMBASE, the Cochrane Oral Health Group Trials Register, and CENTRAL and identify all relevant papers published between 1980 and January 19, 2013. Unpublished literature at ClinicalTrials.gov, in the National Research Register, and in the Pro-Quest Dissertation Abstracts and Thesis database was also included. Studies were included irrespective of language. These results were supplemented by hand and gray literature searches. RESULTS: Twenty-two studies were identified. Twenty were retrospective cohort studies, one was a prospective cohort study, and one was a case control study. The main indication for CBCT was dental implant treatment planning, and the majority of studies used a small field of view for imaging. The most common anatomical variations included increased thickness of the sinus membrane, the presence of sinus septa, and pneumatization. Reported sinus disease frequency varied widely, ranging from 14.3% to 82%. There was a wide range in the reported prevalence of mucosal thickening related to apical pathology, the degree of lumenal opacification, features of sinusitis, and the presence of retention cysts and polyps. More pathologic findings in the maxillary sinus were reported in men than in women, and the medial wall and sinus floor were most frequently affected. CONCLUSION: CBCT is used primarily to evaluate bony anatomy and to screen for overt pathology of the maxillary sinuses prior to dental implant treatment. Differences in the classification of mucosal findings are problematic in the consistent and valid assessment of health and disease of the maxillary sinus.