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Topic:Computed Tomography

Computed Tomography (CT) in horses is an advanced imaging technique used to obtain detailed cross-sectional images of equine anatomy. This non-invasive method utilizes X-ray technology combined with computer processing to create detailed images of bones, soft tissues, and other internal structures. CT is particularly useful for diagnosing complex conditions in the head, neck, and limbs of horses, offering enhanced visualization compared to traditional radiography. The technique is valuable for identifying fractures, dental issues, sinus diseases, and other abnormalities. This page compiles peer-reviewed research studies and scholarly articles that explore the applications, advancements, and clinical implications of computed tomography in equine medicine.
Usefulness of caudomedial-craniolateral oblique radiographic views for the diagnosis of injury to the origin of the cranial cruciate ligament in two horses.
Journal of the American Veterinary Medical Association    February 5, 2019   Volume 254, Issue 4 508-511 doi: 10.2460/javma.254.4.508
Aldrich ED, Goodrich LR, Contino EK, Kawcak CE, Barrett MF, King MR, Valdés-Martínez A.CASE DESCRIPTION A 12-year-old mixed-breed mare (horse 1) and 6-year-old Friesian gelding (horse 2) were examined for chronic lameness associated with the stifle joint. CLINICAL FINDINGS Lameness examination revealed effusion of the right (horse 1) or left (horse 2) femoropatellar and medial femorotibial joints and grade 3/5 (horse 1) or 4/5 (horse 2) lameness. A diagnosis of cranial cruciate ligament (CCL) injury with associated mineralization and avulsion (horse 1) or mineralization alone (horse 2) was facilitated in both horses with a caudomedial-craniolateral oblique radiographic view obta...
Computed tomographic dimensions of the normal adult equine eye.
Veterinary ophthalmology    February 4, 2019   Volume 22, Issue 5 651-659 doi: 10.1111/vop.12636
Hollis AR, Dixon JJ, Berlato D, Murray R, Weller R.There are limited data on whether the dimensions of the equine eye and its internal structures change with bodyweight in horses. The aim of this study was to identify whether the size of the equine eye and its individual structures varied in a predictable manner with bodyweight, and to examine the reliability of computed tomography (CT) scans in the measurement of the equine eye. Ninety horses which had undergone CT examination of the head for non-ocular disease were included. All measurements of the eye were performed twice on all eyes by the same operator to quantify intra-operator agreement...
Three-dimensional CT observation of position and movability of the scapula in the horse using carcasses of Falabella.
Anatomia, histologia, embryologia    January 29, 2019   Volume 48, Issue 3 250-255 doi: 10.1111/ahe.12430
Endo H, Nguyen ST, Yoshida M, Kudo K.The three-dimensionally real position and movement of the scapula in the lateral side of the ribcage could not be clarified in the horse, since the body size of the horse is too large to apply the CT scanning and image analysis methods. In this study, therefore, we examined the position and the movability of scapula using a carcass of the Falabella which is one of the smallest breeds of the horse. The whole skeletal system in thoracic part of the Falabella could be three-dimensionally observed by CT scanning method. The three-dimensional images show that the scapula cranially slides and the ve...
Osteochondroma of the First Phalanx in Tbourida Horses.
Frontiers in veterinary science    January 8, 2019   Volume 5 328 doi: 10.3389/fvets.2018.00328
Seghrouchni M, Bollo E, Piro M, Alyakine H, Bouayad H, Chakir J, Azrib R, Allali KE.This study aimed at describing anatomo-histopathological and imaging features, using computed tomography and magnetic resonance imaging on six forelimbs of Tbourida horses, that presented a particular bone exostosis on the dorsal and proximal part of the first phalanx, diagnosed by X-ray. Gross anatomy of the bone exostosis revealed an irregular surface with poly-lobulated tissue masses showing a cauliflower shape. The diameter/depth varied from 0.5 to 5.1 cm with a mean of 3.9 ± 0.9 cm. The capsule of the metacarpophalangeal joint was hypertrophic and showed many invaginations in the inner ...
Communication between the distal interphalangeal joint and the navicular bursa in the horse at Computed Tomography Arthrography.
Anatomia, histologia, embryologia    January 4, 2019   Volume 48, Issue 2 133-141 doi: 10.1111/ahe.12421
Hontoir F, Rejas E, Falticeanu A, Nisolle JF, Simon V, Nicaise C, Clegg PD, Vandeweerd JE.Diffusion of drugs injected into the distal interphalangeal joint or the navicular (podotrochlear) bursa can influence diagnosis and treatment of foot pain. Previous anatomical and radiographic studies of the communication between these synovial structures have produced conflicting results and did not identify the location of any communication if present. This anatomic study aimed to assess the presence and site of communication between the distal interphalangeal joint and the navicular bursa in the horse by computed tomography arthrography. Sixty-six pairs of cadaver forelimbs were injected w...
Outcome following computed tomographic imaging and subsequent surgical removal of keratomas in equids: 32 cases (2005-2016).
Journal of the American Veterinary Medical Association    January 4, 2019   Volume 254, Issue 2 266-274 doi: 10.2460/javma.254.2.266
Katzman SA, Spriet M, Galuppo LD.OBJECTIVE To describe the use of CT in the diagnosis of and presurgical planning for equids with keratomas treated by hoof wall resection and determine postoperative complications and outcome. DESIGN Retrospective case series. ANIMALS 29 horses and 3 mules with keratomas treated by partial or complete hoof wall resection following CT imaging of the distal portion of the affected extremity from 2005 through 2016. PROCEDURES For each equid, physical examination and lameness evaluation were performed, followed by imaging of the distal portion of the affected extremity. A tentative diagnosis of ke...
Impact of a void in the equine medial femoral condyle on bone stresses and peak contact pressures in a finite element model.
Veterinary surgery : VS    December 16, 2018   Volume 48, Issue 2 237-246 doi: 10.1111/vsu.13139
Frazer LL, Santschi EM, Fischer KJ.To predict bone and medial meniscal stresses and contact pressures in an equine stifle with a medial femoral condyle (MFC) intact or with a 2-cm subchondral bone void, under varying degrees of internal femoral rotation (IFR). Methods: Finite element model (FEM) of a cadaveric equine stifle loaded to 8000 N. Methods: The FEM was constructed from computed tomography (CT) of the right, extended stifle of a yearling. The CT image was segmented into relevant anatomic structures and meshed into 4-node tetrahedrons. Bone material properties were assigned according to Hounsfield units, soft tissue p...
Quantitative Evaluation of Equine Articular Cartilage Using Cationic Contrast-Enhanced Computed Tomography.
Cartilage    December 2, 2018   Volume 12, Issue 2 211-221 doi: 10.1177/1947603518812562
Nelson BB, Stewart RC, Kawcak CE, Freedman JD, Patwa AN, Snyder BD, Goodrich LR, Grinstaff MW.To investigate the diffusion trajectory of a cationic contrast medium (CA4+) into equine articular cartilage, and to assess normal and degenerative equine articular cartilage using cationic contrast-enhanced computed tomography (CECT). In the first experiment (Exp1), equine osteochondral specimens were serially imaged with cationic CECT to establish the diffusion time constant and time to reach equilibrium in healthy articular cartilage. In a separate experiment (Exp2), articular cartilage defects were created on the femoral trochlea (defect joint) in a juvenile horse, while the opposite joint...
The prevalence of temporal bone fractures is high in horses with severe temporohyoid osteoarthropathy. Tanner J, Spriet M, Espinosa-Mur P, Estell KE, Aleman M.Temporohyoid osteoarthropathy is a well-recognized cause of equine neurologic disease. Temporal bone fractures associated with temporohyoid osteoarthropathy have been recognized with CT, however, little information is available regarding these fractures. The aims of this retrospective analytical study were to assess the prevalence of these fractures and to describe the specific configurations and associated imaging and clinical features. Fracture of the temporal bone was identified with CT in 16 of 39 included horses. All fractures were unilateral, minimally displaced and extended through the ...
In vitro comparison of linear vs triangular screw configuration to stabilize complete uniarticular parasagittal fractures of the proximal phalanx in horses.
Veterinary surgery : VS    November 7, 2018   Volume 48, Issue 1 96-104 doi: 10.1111/vsu.13123
Labens R, Khairuddin NH, Murray M, Jermyn K, Ahmad RS.To assess fracture gap reduction and stability of linear vs triangular 4.5-mm lag screw repair of experimental, uniarticular, and complete forelimb proximal phalanx (P1) fractures. Methods: Experimental. Methods: Fourteen equine cadaver limbs/horses. Methods: Simulated fractures were repaired with 2 lag screws under 4-Nm insertion torque (linear repair). Computed tomography (CT) imaging was performed with the leg unloaded and loaded to forces generated while walking. The fracture repair was revised to include 3 lag screws placed with the same insertion torque (triangular repair) prior to CT. T...
Extradural spinal hydatid cyst causing hindlimb ataxia in a horse.
Schweizer Archiv fur Tierheilkunde    November 1, 2018   Volume 160, Issue 11 659-664 doi: 10.17236/sat00183
Peter V, Marr C, Foote A, Auer H, Head M.This case report describes a 13-year-old cob-cross gelding presented for evaluation of recent onset hindlimb ataxia. The gelding had undergone general anaesthesia and tenoscopy of the right hindlimb digital flexor tendon sheath at a nearby clinic three months earlier and had appeared normal at routine post-operative assessments until the sudden onset of neurological deficits. Spinal trauma was suspected initially but radiography and scintigraphy were unremarkable. Due to the severity and progressive nature of the clinical signs the -gelding was subjected to euthanasia. Post mortem examinations...
Use of an aiming device and computed tomography for assisted debridement of subchondral cystic lesions in the limbs of horses.
Veterinary surgery : VS    October 31, 2018   Volume 48, Issue S1 O15-O24 doi: 10.1111/vsu.13112
Jackson MA, Ohlerth S, Fürst AE.To describe the use of an aiming device (AD) and computed tomography (CT) for preoperative planning and intraoperative guided debridement of subchondral cystic lesions (SCL) in the limbs of horses and to determine the outcome 12 months after surgery. Methods: Prospective case series. Methods: Twelve horses referred because of lameness caused by 1 or 2 SCL (total of 14 SCL). Methods: All horses underwent CT-guided debridement of the SCL. The entry point of the drill bit and direction of drilling were planned and controlled by using a series of CT images and the AD. The SCL were curetted and fil...
Diffusion of charged and uncharged contrast agents in equine mandibular condylar cartilage is not affected by an increased level of sugar-induced collagen crosslinking.
Journal of the mechanical behavior of biomedical materials    October 14, 2018   Volume 90 133-139 doi: 10.1016/j.jmbbm.2018.10.022
Mirahmadi F, Koolstra JH, Fazaeli S, Lobbezoo F, van Lenthe GH, Snabel J, Stoop R, Everts V.Nutrition of articular cartilage relies mainly on diffusion and convection of solutes through the interstitial fluid due to the lack of blood vessels. The diffusion is controlled by two factors: steric hindrance and electrostatic interactions between the solutes and the matrix components. Aging comes with changes in the cartilage structure and composition, which can influence the diffusion. In this study, we treated fibrocartilage of mandibular condyle with ribose to induce an aging-like effect by accumulating collagen crosslinks. The effect of steric hindrance or electrostatic forces on the d...
18 F-sodium fluoride positron emission tomography of the racing Thoroughbred fetlock: Validation and comparison with other imaging modalities in nine horses.
Equine veterinary journal    September 28, 2018   Volume 51, Issue 3 375-383 doi: 10.1111/evj.13019
Spriet M, Espinosa-Mur P, Cissell DD, Phillips KL, Arino-Estrada G, Beylin D, Stepanov P, Katzman SA, Galuppo LD, Garcia-Nolen T, Murphy B, Stover SM.Early and accurate detection of stress remodelling in racehorses is of utmost importance to prevent catastrophic injuries. Current imaging techniques have limitations in assessing early changes predisposing to catastrophic breakdowns. Positron emission tomography (PET) using F-sodium fluoride ( F-NaF) is a sensitive method for the detection of early bone turnover and may improve early recognition of subtle injuries. Objective: To validate the clinical use of F-NaF PET in Thoroughbred racehorses, to assess the value of PET in the detection of bone lesions and to compare PET results with findi...
Disease-Modifying Osteoarthritis Treatment With Interleukin-1 Receptor Antagonist Gene Therapy in Small and Large Animal Models.
Arthritis & rheumatology (Hoboken, N.J.)    September 10, 2018   Volume 70, Issue 11 1757-1768 doi: 10.1002/art.40668
Nixon AJ, Grol MW, Lang HM, Ruan MZC, Stone A, Begum L, Chen Y, Dawson B, Gannon F, Plutizki S, Lee BHL, Guse K.Gene therapy holds great promise for the treatment of osteoarthritis (OA) because a single intraarticular injection can lead to long-term expression of therapeutic proteins within the joint. This study was undertaken to investigate the use of a helper-dependent adenovirus (HDAd)-mediated intraarticular gene therapy approach for long-term expression of interleukin-1 receptor antagonist (IL-1Ra) as sustained symptomatic and disease-modifying therapy for OA. In mouse models of OA, efficacy of HDAd-IL-1Ra was evaluated by histologic analysis, micro-computed tomography (micro-CT), and hot plate ana...
Cervical stabilization with polyaxial pedicle screw and rod construct in horses: A proof of concept study.
Veterinary surgery : VS    September 10, 2018   Volume 47, Issue 7 932-941 doi: 10.1111/vsu.12938
Aldrich E, Nout-Lomas Y, Seim HB, Easley JT.To evaluate safety and efficacy of a novel technique for cervical stabilization. Methods: In vivo experimental. Methods: Four normal adult quarterhorse crossbreed horses (2-4 years of age, > 250 kg). Methods: One mid-cervical spinal unit (C3-C4) was distracted with a porous metal interbody fusion device (IFD) and stabilized with a polyaxial pedicle screw and rod construct. Neurologic examinations were performed preoperatively and postoperatively. Radiographs of the fusion site and adjoining vertebrae were obtained preoperatively and monthly. Horses were euthanized at 8 months and spin...
Aging does not change the compressive stiffness of mandibular condylar cartilage in horses.
Osteoarthritis and cartilage    August 23, 2018   Volume 26, Issue 12 1744-1752 doi: 10.1016/j.joca.2018.08.007
Mirahmadi F, Koolstra JH, Fazaeli S, Lobbezoo F, van Lenthe GH, Snabel J, Stoop R, Arbabi V, Weinans H, Everts V.Aging can cause an increase in the stiffness of hyaline cartilage as a consequence of increased protein crosslinks. By induction of crosslinking, a reduction in the diffusion of solutions into the hyaline cartilage has been observed. However, there is a lack of knowledge about the effects of aging on the biophysical and biochemical properties of the temporomandibular joint (TMJ) cartilage. Hence, the aim of this study was to examine the biophysical properties (thickness, stiffness, and diffusion) of the TMJ condylar cartilage of horses of different ages and their correlation with biochemical p...
Use of crown height of the maxillary first molar tooth to approximate the age of horses.
American journal of veterinary research    July 31, 2018   Volume 79, Issue 8 867-873 doi: 10.2460/ajvr.79.8.867
Carmalt JL, Henderson KV, Rawlinson JE, Waldner CL.OBJECTIVE To identify whether age, sex, or breed is associated with crown height of the left and right maxillary first molar tooth (M1) measured on CT images, to develop a mathematical model to determine age of horses by use of M1 crown height, and to determine the correlation between M1 crown height measured on radiographic and CT images. SAMPLE CT (n = 735) and radiographic images (35) of the heads of horses. PROCEDURES Crown height of left and right M1 was digitally measured on axial CT views. Height was measured on a lateral radiographic image when available. Linear regression analysis was...
Diagnosis of Skeletal Injury in the Sport Horse.
The Veterinary clinics of North America. Equine practice    July 17, 2018   Volume 34, Issue 2 193-213 doi: 10.1016/j.cveq.2018.04.014
Wulster KB.This article discusses the basis of image formation of radiography, scintigraphy, PET, computed tomography (fan beam and cone beam), and magnetic resonance as it relates to imaging of musculoskeletal injury in the sport horse. The benefits and drawbacks of each modality are discussed with particular emphasis on sensitivity, specificity, and accuracy of identification of subchondral bone injury. Examples of straightforward as well as confounding lesions are provided, emphasizing the need for appropriate clinical workup and diagnostic analgesia, where appropriate.
Arthroscopic approach and intra-articular anatomy of the equine atlanto-occipital joint.
Veterinary surgery : VS    July 13, 2018   Volume 47, Issue 6 756-767 doi: 10.1111/vsu.12932
Wright L, Puchalski SM, Kristoffersen M, Lindegaard C.To develop arthroscopic approaches to the atlanto-occipital (A-O) and describe associated arthroscopic anatomy. Methods: Experimental ex vivo study and clinical case report. Methods: Ten equine cadaver joints and 1 clinical case. Methods: CT arthrograms of 8 A-O joints were performed to determine the placement of an arthroscopic portal. Arthroscopy was performed via dorsal and/or ventral approaches (dorsal or ventral to the longissimus capitis tendon) in 10 cadaveric A-O joints and the A-O joint of a 2-week-old foal with septic arthritis. Accessible cartilage was debrided in 3 cadaver joints. ...
Echocardiographic identification of atrial-related structures and vessels in horses validated by computed tomography of casted hearts.
Equine veterinary journal    June 29, 2018   Volume 51, Issue 1 90-96 doi: 10.1111/evj.12969
Vandecasteele T, Cornillie P, van Steenkiste G, Vandevelde K, Gielen I, Vanderperren K, van Loon G.Echocardiography is the imaging technique of choice for the equine heart. Nevertheless, knowledge about ultrasonographic identification of dorsally located structures and vessels, related to the atria, in horses is scarce. Objective: To describe the echocardiographic approach and the identification of structures and vessels in relation to the atria in healthy horses. Methods: CT images from two equine hearts, casted with self-expanding foam, were segmented and used to identify atrial-related structures and vessels. These images were compared with standard and nonstandard ultrasound images from...
Comparison of conventional radiography and computed tomography as aids in the diagnosis of osteomyelitis in 11 foals.
Australian veterinary journal    June 27, 2018   Volume 96, Issue 7 257-261 doi: 10.1111/avj.12710
Lean NE, Perkins NR, Ahern BJ.Conventional radiography is currently the most common imaging modality used by veterinarians investigating foals with suspected osteomyelitis. Emerging evidence in adult horses and humans suggests computed tomography (CT) is a superior modality for evaluation of osseous changes in general. This study aimed to evaluate the potential benefits of CT versus conventional radiography in cases of osteomyelitis in foals. Methods: Cases of osteomyelitis in foals under 6 months of age admitted over a 6-year period at a single referral hospital that had both CT and conventional radiography images were ...
Evaluation of the equine mental foramen block: cadaveric and in vivo injectate diffusion.
Veterinary anaesthesia and analgesia    June 19, 2018   Volume 45, Issue 6 839-848 doi: 10.1016/j.vaa.2018.06.002
Rawlinson JE, Bass L, Campoy L, Lesser C, Prytherch B.To describe injectate diffusion for two equine mental foramen block techniques. Methods: Descriptive anatomic study. Methods: A total of 12 equine heads and three live horses. Methods: Equine heads were longitudinally sectioned to create 24 hemi-heads for testing two mental foramen block techniques (T1 and T2) and two injectate volumes (3 and 5 mL) of mixed dye and contrast medium. T1 needles were directed rostrocaudally into the mental foramen for 3 cm, and T2 needles were directed dorsolaterally to ventromedially into the foramen for 1 cm. Hemi-heads were randomly assigned one injection tech...
Statistical modeling of the equine third metacarpal bone incorporating morphology and bone mineral density.
PloS one    June 6, 2018   Volume 13, Issue 6 e0194406 doi: 10.1371/journal.pone.0194406
Liley H, Zhang J, Firth EC, Fernandez JW, Besier TF.The objective of this study was to describe the three-dimensional shape and subchondral bone mineral density (BMD) variation of the equine distal third metacarpal bone (MC3) using a statistical shape model. The association between form and function builds upon previous two-dimensional observations of MC3 epiphyseal structure. It was expected that the main source of variation would be an increase in overall MC3 bone size, correlated to an increase in subchondral BMD. Geometry and bone mineral density was obtained from CT image data of 40 healthy Thoroughbred horses. This was used to create a st...
Can quantitative computed tomography detect bone morphological changes associated with catastrophic proximal sesamoid bone fracture in Thoroughbred racehorses?
Equine veterinary journal    June 1, 2018   Volume 51, Issue 1 123-130 doi: 10.1111/evj.12965
Cresswell EN, McDonough SP, Palmer SE, Hernandez CJ, Reesink HL.Fracture of the proximal sesamoid bones continues to be the most common fatal musculoskeletal injury in US racehorses. Identifying factors that influence fracture risk could lead to screening techniques to reduce catastrophic injury rates and improve animal welfare. Objective: To identify morphological differences between proximal sesamoid bones of the contralateral limb of fracture and control horses and assess the feasibility of computed tomography (CT) to detect traits associated with proximal sesamoid bone fracture. We hypothesised that horses with proximal sesamoid bone fracture would hav...
Diagnosis of Soft Tissue Injury in the Sport Horse.
The Veterinary clinics of North America. Equine practice    May 28, 2018   Volume 34, Issue 2 215-234 doi: 10.1016/j.cveq.2018.04.009
Bubeck KA, Aarsvold S.For successful diagnosis of soft tissue injuries in the sport horse, localizing the area of injury during clinical and lameness evaluation will be followed in most cases by an ultrasonographic examination. With MRI more available in equine veterinary clinics, this modality can allow for a complete evaluation of soft tissue and osseous structures and is especially useful for evaluation of structures within the hoof capsule. This article discusses special ultrasonographic techniques, an overview of MRI image generation, and the use of contrast computed tomography for diagnosis of soft tissue inj...
Paranasal sinus cysts in the horse: Complications related to their presence and surgical treatment in 37 cases.
Equine veterinary journal    May 17, 2018   Volume 51, Issue 1 57-63 doi: 10.1111/evj.12959
Fenner MF, Verwilghen D, Townsend N, Simhofer H, Schwarzer J, Zani DD, Bienert-Zeit A.Paranasal sinus cysts (PSC) are a common cause of equine secondary sinusitis. The outcome and associated complications have not been frequently reported. Objective: To review the associated clinical signs, associated morbidities and outcomes of horses treated for PSC. Methods: Retrospective multicentre case series. Methods: Retrospective analysis of case records and telephone follow up survey. Results: Subjects were 37 horses 1-24 years old that were presented with nasal discharge (n = 31), facial swelling (n = 25) and epiphora (n = 19). Radiography and computed tomography allowed identificati...
Subchondral bone microdamage accumulation in distal metacarpus of Thoroughbred racehorses.
Equine veterinary journal    May 12, 2018   Volume 50, Issue 6 766-773 doi: 10.1111/evj.12948
Whitton RC, Ayodele BA, Hitchens PL, Mackie EJ.Microdamage accumulation leads to subchondral bone injury and/or fracture in racehorses. An understanding of this process is essential for developing strategies for injury prevention. Objective: To quantify subchondral bone microdamage in the third metacarpal bone of Thoroughbred racehorses at different stages of the training cycle. Methods: Cross-sectional. Methods: Bone blocks from the palmar aspect of the medial condyles of third metacarpal bones from 46 racing Thoroughbred horses undergoing post-mortem were examined with micro computed tomography (microCT) to detect calcified microcracks, ...
Computed tomographic description of the highly variable imaging features of equine oromaxillary sinus and oronasal fistulae. Hargreaves L, Dixon JJ.Oronasal and oromaxillary sinus fistulae are well-documented complications following removal or loss of a maxillary cheek tooth. Diagnosis is currently based on a combination of oral examination, videoendoscopy, radiography, and computed tomography (CT). The objective of this retrospective, case series study was to describe the CT characteristics of confirmed oronasal and oromaxillary sinus fistulae in a group of horses. Inclusion criteria were a head CT acquired at the authors' hospital during the period of 2012-2017, a CT diagnosis of oronasal or oromaxillary sinus fistulae, and a confirmed ...
Anatomy of equine incisors: Pulp horns and subocclusal dentine thickness.
Equine veterinary journal    May 7, 2018   Volume 50, Issue 6 854-860 doi: 10.1111/evj.12841
Englisch LM, Rott P, Lüpke M, Seifert H, Staszyk C.Equine incisors are often reduced in height during corrective dental procedures. Increased knowledge of subocclusal dentine thickness and pulp morphology may help prevent iatrogenic pulpar exposure. Although such data exist for equine cheek teeth, there are currently no reliable data for incisors. Objective: To measure the distances between pulp cavities and the occlusal as well as the labial surfaces of equine incisors and to test if these distances change with age. Furthermore, pulp morphology with regard to number and orientation of pulp horns was investigated. Methods: Observational study ...
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