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1.
J Clin Pediatr Dent ; 44(1): 52-54, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31995413

RESUMEN

Oral ulcerations in children and adolescents is a common occurrence and affects about 20-30% of this population. This case report describes a unique and serious autoimmune condition that presented with distinct oral findings that significantly supported the differential diagnosis of Juvenile Systemic Lupus Erythematosus in a 15 year-old female. Pediatric and general dentists should familiarize themselves with the condition to facilitate diagnosis with collaborative efforts with the medical team.


Asunto(s)
Enfermedades Autoinmunes , Lupus Eritematoso Sistémico , Úlceras Bucales , Adolescente , Niño , Diagnóstico Diferencial , Femenino , Humanos
2.
Head Neck Pathol ; 15(3): 917-922, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33686583

RESUMEN

Gingival growths, barring a few are mostly reactive and seldom exhibit significant true neoplastic potential. The common etiology is local irritation from dental plaque/calculus, trauma as well as medication-related overgrowth. Such lesions are easily distinguishable and categorized into diagnoses such as pyogenic granuloma, peripheral ossifying fibroma, etc. We present a previously undescribed, but commonly encountered, reactive gingival growth with unique histologic features and suggest the diagnostic term "gingival fibroma." An IRB approved retrospective review of the University of Florida Oral Pathology Biopsy Service encompassing years 2010-2019, was performed to select cases. Demographics, clinical data, and microscopic diagnoses were recorded and analyzed. Four board-certified oral and maxillofacial pathologists agreed upon and established the diagnostic criteria. These are: a prominent fibromyxoid stroma, variable cellularity, a whorled or storiform pattern of arrangement of the cellular elements, lack of significant inflammation or vascularity, and complete absence of calcification, and/or odontogenic islands. A total of 60 cases met all criteria and were included in the study. Age range in years was 14-87 with the mean at 45.11 years. A striking female predilection (90%) was noted. Approximately 62% of cases were reported on the maxillary gingiva, followed by 38.3% in the mandibular gingiva. Majority, 66.7% were in the anterior incisor region followed by 11.7% in the canine/first premolar areas. All lesions were submitted as excisional biopsy, and 4 cases recurred within 2-3 years of excision. In all cases, lesional tissue appeared to extend to the surgical base of the specimen. We present 60 cases of a histologically unique entity occurring exclusively on the gingiva and introduce the diagnostic term "Gingival Fibroma" for these lesions. Further studies with adequate clinical follow-up may help understand the exact clinical behavior of these lesions.


Asunto(s)
Fibroma/patología , Neoplasias Gingivales/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
3.
Mymensingh Med J ; 30(2): 555-558, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33830142

RESUMEN

Treacher collins syndrome (TCS) or Franceschetti syndrome is an autosomal dominant inherited disorder with variable expressivity. It affects mainly craniofacial structure that derives from 1st and 2nd branchial arches approximately between the 20th day and 12th week of intrauterine life. This syndrome has different clinical types. Most common features are antimongoloid slanting of the palpebral fissures, hypoplasia of zygoma, maxilla & mandible with various eye and ear abnormalities. Here we present a case of an 11 days old female neonate, who was ill looking, dyspnoeic having significant facial profile, multiple congenital anomalies and dolicocephaly; admitted in the department of Neonatology, Mymensingh Medical College Hospital (MMCH), Mymensingh, Bangladesh on 7th August 2020. After taking all the diagnostic assistance of the multidisciplinary approach mainly on the basis of clinical features and radiology we diagnosed the case as TCS. We managed the patient by maintaining temperature, giving nutritional support and injectable antibiotic, took consultation from Otolaryngology department then we discharged the baby with proper counseling, advised regarding further follow up and to consult with paediatric surgeon and cardiologist.


Asunto(s)
Anomalías Múltiples , Craneosinostosis , Disostosis Mandibulofacial , Bangladesh , Niño , Femenino , Humanos , Lactante , Recién Nacido , Disostosis Mandibulofacial/diagnóstico por imagen , Disostosis Mandibulofacial/genética , Radiografía
4.
Head Neck Pathol ; 14(2): 353-361, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31079311

RESUMEN

Fibrous dysplasia (FD) is a rare condition commonly involving the jaws. While FD has a typical clinical and histological presentation, considerable variation exists. Moreover, overlap of features with other disorders is possible. This study serves to characterize the features of a large case series of FD of the jaws. With IRB approval, the University of Florida Oral Pathology Biopsy Service archive was retrospectively searched from 1994 to 2015 for cases of FD. Epidemiological data, location, duration, clinical and radiographic appearance, clinical impression and exact microscopic diagnosis were recorded. The average age was 37.3 years (range 7-87 years) with majority of cases in females (67.5%). The most common ethnicity was Caucasian. Maxillary location was predominant (59%), followed by mandible (38%) and multiple locations (3%). Expansion was reported in 78% of cases. Radiographically, most cases exhibited ground glass opacity, however some presented with a mottled or mixed radiopaque/radiolucent appearance. Histologically, a wide variation in terms of stromal cellularity, presence of osteoblastic rimming, and presence of calcified material mimicking cemento-osseous dysplasia was observed. Clinicians and pathologists should be cognizant of the significant variability in clinical, histopathologic, and radiographic presentation of FD, which may pose a diagnostic challenge.


Asunto(s)
Displasia Fibrosa Craneofacial/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
5.
Head Neck Pathol ; 14(4): 1021-1027, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32506377

RESUMEN

Odontogenic myxoma (OM) is an uncommon benign odontogenic tumor arising in the jaw. Though it has slight histologic overlap with other entities, definitive diagnosis is imperative considering the tumor's aggressive nature, high recurrence rate, and necessity of radical surgical intervention in large-sized lesions. With IRB approval, a retrospective search of the University of Florida College of Dentistry Oral Pathology Biopsy Service archives from 1994 to 2017 for diagnosis of OM of the jaw was performed. Biopsy reports and original slides for each case were assessed and reviewed along with any accompanying radiographs to confirm the diagnosis. Immunohistochemical staining was utilized to exclude entities with histologic overlaps, such as intraosseous myxoid neurofibroma. A total of 38 cases were included. The patients' age ranged from 6 to 84 years, with a mean age of 37.47 years. Females comprised two-thirds of the cases (n = 25) versus males (n = 13). The mandible was the most affected at 60.5% (n = 23), followed by maxilla 39.4% (n = 15). Posterior jaw involvement was higher than anterior in both the mandible (n = 20 versus n = 3) and the maxilla (n = 11 versus n = 4). Most lesions presented clinically as expansile masses with variable radiographic appearance. The clinical impression from submitting providers included "gelatinous masses", abscesses, odontogenic lesions, fibro-osseous lesions, soft tissue or bone neoplasms, and reactive gingival lesions. A consensus of odontogenic myxoma as a diagnosis was rendered for 30 cases (79%), while in 8 cases (21%) that exhibited a more fibrous stroma was identified as fibromyxoma. OM may exhibit a varied demographic and clinical profile with a wide spectrum of histologic presentations. Pathologists should be sentient of this variability in order to arrive at an accurate diagnosis and correctly manage these patients.


Asunto(s)
Neoplasias Maxilomandibulares/patología , Mixoma/patología , Tumores Odontogénicos/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
6.
Head Neck Pathol ; 13(4): 573-579, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30671763

RESUMEN

Verrucous hyperkeratosis (VH), verrucous carcinoma (VC) and the relentless, truly pre-malignant variant proliferative verrucous leukoplakia often exhibit lichenoid histologic features that may create a diagnostic dilemma for pathologists. This study aims to evaluate and categorize the frequency and the histopathologic patterns of lichenoid features seen in these lesions. Following IRB approval, cases of VH and VC from 1994 to 2014 were retrieved from the archives of UF Oral Pathology Biopsy Service. A panel of 4 board-certified oral and maxillofacial pathologists reviewed and scored the presence or absence of 5 lichenoid features: band-like infiltrate (BLI), saw tooth rete ridges (STRR), interface stomatitis (IS), civatte bodies (CB), and basement membrane degeneration (BMD). Cases not fulfilling the stringent selection criteria were excluded. A total of 70 cases of VH and 56 cases of VC were included. Approximately 25% of both VH and VC cases exhibited 3 or more lichenoid features. By Chi square testing, BLI (p = 0.000), IS (p = 0.005), and CB (p = 0.026) were significantly more common in VC than VH. Gingival lesions had significantly less frequent BLI (p = 0.004) and IS (p = 0.024) versus other sites. However, STRR was significantly more common in VH than VC (p = 0.000) in the gingiva. (p = 0.002). Statistical analysis revealed that the only significant valid association was the increased presence of band-like infiltrate in VC over VH (p = 0.001). Lichenoid features are common in both VH and VC and may represent a nonspecific inflammatory response to the dysplasia or malignancy rather than concomitant lichenoid disease. This could lead to significant under diagnoses of these premalignant or potentially malignant lesions by pathologists.


Asunto(s)
Carcinoma Verrugoso/patología , Leucoplasia Bucal/patología , Lesiones Precancerosas/patología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/patología , Adulto Joven
7.
Head Neck Pathol ; 9(2): 196-204, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25113037

RESUMEN

The desmoplastic fibroma (DF) is a rare, fibroblastic lesion of bone that histologically resembles the desmoid tumor of soft tissue. Although classified as benign, it frequently demonstrates aggressive behavior, often causing tooth mobility, extensive bone destruction, and has a moderate to high recurrence rate. We present three cases of DF in the mandible: the first in a 13 year old female involving the mandibular body in the region of teeth #s 27-#28, the second in a 57 year old female with a lesion apical to tooth #30, and the third in a 20-year-old female involving the left posterior mandible. Clinical, histologic, immunohistochemical (IHC) and radiographic features of this rare neoplasm are discussed. The challenges encountered in establishing an accurate diagnosis due to significant microscopic overlap with other spindle cell lesions are also detailed. Additionally, the findings of IHC stains including vimentin, smooth muscle actin, S-100 protein, ß-catenin, HHF-35 and proliferation marker, Ki-67 on 3 cases are reported. The potential for misdiagnosis is high, especially in early lesions, since immunohistochemistry has been reported in literature to be inconsistent when differentiating DFs from other spindle cell lesions. A comparative review of DF and similar entities in the jaws with current considerations in treatment and prognosis is presented.


Asunto(s)
Neoplasias Óseas/diagnóstico , Fibroma Desmoplásico/diagnóstico , Neoplasias Mandibulares/diagnóstico , Actinas/metabolismo , Adolescente , Neoplasias Óseas/metabolismo , Neoplasias Óseas/patología , Femenino , Fibroma Desmoplásico/metabolismo , Fibroma Desmoplásico/patología , Humanos , Neoplasias Mandibulares/metabolismo , Neoplasias Mandibulares/patología , Persona de Mediana Edad , Proteínas S100/metabolismo , Vimentina/metabolismo , Adulto Joven , beta Catenina/metabolismo
8.
Artículo en Inglés | MEDLINE | ID: mdl-25840514

RESUMEN

OBJECTIVES: Oral premalignant and malignant lesions may mimic oral lichen planus (OLP) clinically and microscopically. OLP often shows basement membrane fibrinogen positivity on direct immunofluorescence testing (DIF). This study examined fibrinogen positivity in oral premalignant lesions and squamous cell carcinoma. STUDY DESIGN: The University of Florida Oral Pathology Biopsy Service records were searched for the years 2003 to 2013 for oral premalignant lesions and squamous cell carcinoma with concurrent DIF testing. Demographic, clinical, and DIF or histologic information was collected and analyzed. RESULTS: Sixty-eight fibrinogen positive lesions were identified within a total of 164 cases. Low-grade dysplasia and premalignant verrucous lesions made up the majority of the fibrinogen positive lesions (combined n = 43; 63.2%), and the most common locations in positive cases were the buccal mucosa, tongue, and gingiva. A lichenoid distribution of the inflammatory infiltrate significantly predicted fibrinogen positivity (P < .0005). CONCLUSIONS: Fibrinogen positivity may be seen in premalignant and malignant oral lesions increasing the risk of misdiagnosis.


Asunto(s)
Carcinoma de Células Escamosas/patología , Técnica del Anticuerpo Fluorescente Directa , Neoplasias de la Boca/patología , Lesiones Precancerosas/patología , Anciano , Biopsia , Transformación Celular Neoplásica/patología , Femenino , Fibrinógeno/análisis , Humanos , Liquen Plano Oral/patología , Masculino , Persona de Mediana Edad
9.
Ann Thorac Surg ; 31(6): 569-73, 1981 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6972748

RESUMEN

Despite widespread success with Gore-Tex (polytetrafluoroethylene) vascular grafts in peripheral artery operations, very little use has been made of this material in aortocoronary bypasses. We present the case of a 61-year-old woman with a 6-month history of angina who was found to have no suitable saphenous vein available at operation and who therefore underwent Gore-Tex bypass grafting to the right coronary artery. Coronary angiograms made 6 months and 18 months postoperatively showed patency of the 6 mm Gore-Tex replacement graft as well as the internal mammary artery placed to the left anterior descending coronary artery. Although frequent follow-up and close observation are recommended in patients with aortocoronary Gore-Tex grafting, the unique design of this material has made it the best alternative for synthetic coronary bypass conduit in the absence of the saphenous veins, particularly when these veins are found to be inadequate only at the time of operation.


Asunto(s)
Prótesis Vascular , Vasos Coronarios/cirugía , Angiografía Coronaria , Puente de Arteria Coronaria/métodos , Femenino , Humanos , Anastomosis Interna Mamario-Coronaria , Persona de Mediana Edad , Politetrafluoroetileno
10.
Ann Anat ; 182(6): 499-503, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11125797

RESUMEN

The cemento-dentinal junction was examined in demineralized rat molars with complete roots by scanning electron microscopy combined with NaOH maceration. It is established that the NaOH maceration removes interfibrillar substances and cells from connective tissues selectively without structural damage to collagen fibrils. The cementum was detached from the dentin by the maceration. The inner cementum surface facing the dentin and the outer dentin surface facing the cementum were observed. In acellular cementum, both the outer dentin surface and the inner cementum surface had a smooth appearance. There was little indication of fibrils intermingling between dentin and cementum. In contrast, both the inner cementum surface and outer dentin surface in cellular cementum had an uneven appearance due to the irregular arrangement of collagen fibrils. Point-like protrusions of fibril bundles were observed on both surfaces. Some (not all) of these point-like protrusions appeared to correspond to places of fibrillar intermingling between dentin and cementum.


Asunto(s)
Colágeno/análisis , Cemento Dental/ultraestructura , Dentina/ultraestructura , Diente Molar/ultraestructura , Animales , Masculino , Microfibrillas/ultraestructura , Microscopía Electrónica de Rastreo , Ratas
11.
Ann Anat ; 183(5): 481-3, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11677815

RESUMEN

This study was designed to evaluate whether resin embedded transparent teeth are as convenient to use as classical transparent teeth. For this purpose demineralized human teeth were divided into coronal and radical portions, and pulp tissue was extracted from the pulp chamber and root canals, into which drawing ink was injected. After dehydration, the specimens were made transparent in methyl salicylate and immersed in polyester resin. The divided portions were recombined at the polymerization. The resin embedded teeth maintained transparency and the black-stained pulp chamber and root canals showed morphological details. The resin embedded specimens could be handled manually and observed freely from any angle. Previously, transparent teeth have been observed in transparent media through a capped glass bottle. In this respect the resin embedding method is superior to the classical method. The new method will be helpful for investigating root canal morphology.


Asunto(s)
Pulpa Dental/citología , Diente/citología , Técnicas Histológicas , Humanos , Mandíbula , Maxilar , Resinas de Plantas
12.
Ann Anat ; 183(2): 123-8, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11325058

RESUMEN

To elucidate the initial attachment mechanism of cemental fibrils to the root dentin surface in acellular and cellular cementogenesis, developing rat molars were observed by light microscopy and scanning electron microscopy combined with NaOH maceration. The NaOH maceration was used to observe details of the positional association of cemental and dentinal fibrils during cementogenesis. An initial hematoxylin stained, cementum layer began to form on the root dentin surface with the first dentin mineralization in both acellular and cellular cementogenesis. The initial attachment of cemental fibrils to the dentin surface also began at this point. At the initial attachment the intermingling of cemental and dentinal fibrils occurred only in places. With advanced cementogenesis the initial cementum layer became the fibril-poor cemento-dentinal junction. This suggests that cemental fibrils attach on the initial cementum layer, and not directly on dentinal fibrils, so that the layer results in the fibril-poor cemento-dentinal junction. The present study suggests that an intervening adhesive is necessary for the cemento-dentinal attachment at any stage of cementogenesis in rat molars.


Asunto(s)
Cemento Dental/citología , Cemento Dental/fisiología , Dentina/citología , Diente Molar/citología , Raíz del Diente/citología , Envejecimiento , Animales , Calcificación Fisiológica , Cemento Dental/ultraestructura , Dentina/fisiología , Dentina/ultraestructura , Masculino , Microscopía Electrónica de Rastreo , Diente Molar/fisiología , Diente Molar/ultraestructura , Odontogénesis/fisiología , Ratas , Ratas Wistar , Raíz del Diente/fisiología , Raíz del Diente/ultraestructura
13.
J Forensic Sci ; 40(4): 637-40, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7595302

RESUMEN

We evaluated the usefulness of a semi-nested polymerase chain reaction (PCR) method for detecting D1S80 (pMCT118) locus polymorphisms of DNA extracted from old skeletal remains. The semi-nested PCR has been applied to the amplification of D1S80 nucleic acid sequences. For amplification of the locus D1S80, a pair of oligonucleotide primers have been used widely as described by Kasai et al. We have designed another set of primers for semi-nested PCR. This method resulted in D1S80-VNTR detection from low-titered DNA isolated from old skeletal remains. The first and second step PCR achieved amplification from as little as 10 ng and 10 pg of template DNA, respectively. Specificity and sensitivity of the amplification products was markedly improved by semi-nested PCR. In DNA extracted from biological samples, this method took about 5 hours to amplify the target DNA and 3 hours for electrophoretic separation. We demonstrated that this semi-nested PCR method was superior in sensitivity to conventional 1-step standard amplification for VNTR typing of the D1S80 locus.


Asunto(s)
ADN/genética , Reacción en Cadena de la Polimerasa/métodos , Polimorfismo Genético/genética , Cráneo , Diente , Secuencia de Bases , Antropología Forense , Odontología Forense , Humanos , Datos de Secuencia Molecular , Sensibilidad y Especificidad
14.
Head Neck Pathol ; 8(3): 339-48, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24202723

RESUMEN

Intraoral basal cell carcinoma (IOBCC) is an extremely rare entity that bears close microscopic resemblance to and is often confused with the peripheral ameloblastoma (PA). Basal cell carcinomas are thought to arise from pluripotential basal cells present within surface epithelium and adnexal structures, so theoretically they can arise within the oral cavity. Many of the early cases reported as IOBCC actually represent PA. Most of the well documented cases arise from the gingiva. The histologic features of basal cell carcinoma that help separate it from a PA include: tumor arising from surface epithelium, scattered mitotic figures and apoptotic cells, presence of mucoid ground substance and tumor infiltrating widely throughout the connective tissue and often exhibiting a prominent retraction artifact. Clinically IOBCC resemble carcinomas, compared to the benign and innocuous appearance of the PA and typically presents as surface ulcerations varying from rodent ulcer to an ulcerated erythroplakia appearance. This contrasts with the classic "bump on the gum" appearance of PAs with usually intact surface and appearing as small discrete, sessile, exophytic lesions. Importantly, the proliferative basaloid epithelium demonstrates positive immunoreactivity for the anti-epithelial antibody, Ber-EP4, a cell surface glycoprotein. The IOBCC has the potential for local recurrence and aggressive behavior and should be treated with wide surgical excision and close clinical follow up. We present 3 rare cases of IOBCC and discuss the salient histologic, immunohistochemical and clinical features.


Asunto(s)
Carcinoma Basocelular/patología , Neoplasias de la Boca/patología , Adulto , Anciano , Biomarcadores de Tumor/análisis , Femenino , Humanos , Inmunohistoquímica , Masculino
15.
Head Neck Pathol ; 4(1): 10-4, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20237983

RESUMEN

The location of oral leukoplakia correlates strongly with the probability of finding dysplastic or malignant alterations at biopsy. It is well established that early detection can dramatically improve the 5-year survival rates for oral squamous cell carcinomas. Since aneuploidy is predictive of future conversion to malignancy, we hypothesized that dysplastic lesions from high-risk sites (floor of mouth, tongue and lips) would exhibit greater aneuploidy than low-risk sites (palate, gingiva and buccal mucosa). Epithelial sections from 60 archival samples diagnosed as mild dysplasia (36 females, 20 males) from various high/low risk locations were stained with Blue Feulgen Stain for DNA Ploidy Analysis (Clarient, Aliso Viejo, CA) and ploidy was analyzed using a ChromaVision ACIS II (Clarient, ALiso Viejo, CA) Image cytometry system. A DNA histogram was generated using an image analyzing software that evaluated the amount of Feulgen stain which is proportional to the amount of nuclear DNA. An ANOVA analysis followed by the Student's't' test revealed significant differences between means (P

Asunto(s)
Aneuploidia , Carcinoma de Células Escamosas/patología , Leucoplasia/patología , Neoplasias de la Boca/patología , Boca/patología , Carcinoma de Células Escamosas/genética , ADN de Neoplasias/análisis , Femenino , Humanos , Citometría de Imagen , Leucoplasia/genética , Masculino , Neoplasias de la Boca/genética , Estudios Retrospectivos , Colorantes de Rosanilina
17.
J Periodontal Res ; 35(6): 344-51, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11144407

RESUMEN

This study was designed to observe the principal fibers and alveolar bone in various developmental stages in rat molars using light and transmission electron microscopy and to elucidate the mechanism of initial principal fiber attachment to the alveolar bone surface. Maxillary alveolar bone between the 2nd and 3rd molars of 20- and 25-day-old rats was used. A proteoglycan-rich, fiber-poor, and electron dense layer formed on the alveolar bone surface before the principal fiber organization. This layer was not seen before principal fibers had started to develop. Principal fibers first contacted and then became embedded in this layer. With further development, new bone deposited on this layer and around already attached principal fibers. These findings suggest that this electron dense, proteoglycan-rich layer may act as an adhesive factor to mediate the initial attachment of principal fibers to the alveolar bone surface.


Asunto(s)
Proceso Alveolar/ultraestructura , Colágeno/ultraestructura , Animales , Adhesión Celular , Cemento Dental/ultraestructura , Proteoglicanos/fisiología , Ratas , Ratas Wistar , Propiedades de Superficie
18.
J Periodontal Res ; 35(4): 208-13, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10983881

RESUMEN

The cement lines between reparative cementum and resorbed dentin or cementum in human teeth were observed by light microscopy and scanning electron microscopy combined with NaOH maceration. The NaOH maceration was used to remove interfibrillar substances and to observe the fibrillar architecture of the cement lines directly. Light microscopy showed that the cement lines were rich in proteoglycans with mucopolysaccharides, but deficient in collagen fibrils. The cement lines were artificially broken after treatment with hyaluronidase, which digests some of the mucopolysaccharides, but digests no collagen fibrils. Scanning electron microscopy showed that fibril intermingling occurred only in some places between reparative cementum and resorbed tissue. These findings suggested that the proteoglycans in cement lines mediate the attachment between new and old mineralized tissue.


Asunto(s)
Cemento Dental/ultraestructura , Resorción Radicular/patología , Raíz del Diente/ultraestructura , Técnicas Citológicas , Humanos , Mandíbula , Microscopía Electrónica de Rastreo , Tercer Molar/ultraestructura , Propiedades de Superficie
19.
J Periodontal Res ; 35(2): 59-64, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10863959

RESUMEN

The cemento dentinal junction was studied in acellular and cellular cementum of human mandibular third molars by scanning electron microscopy combined with NaOH-maceration. Scanning electron microscopy with NaOH-maceration was applied to observe the fibrous structure in detail through long sections of the cemento-dentinal junction. In macerated specimens, the cemento dentinal junction was a fibril-poor groove. Some cemental fibrils or fibril bundles penetrated the groove and appeared to intermingle with dentinal fibrils. Prolonged maceration caused detachment of the cemento-dentinal junction irrespective of fibril intermingling allowing observation of the inner cementum surface facing the root dentin. Observations suggested that the fibril intermingling was point-like and present only in places at the cemento-dentinal junction. It was established that NaOH-maceration removes interfibrillar substances effectively in connective tissues and does no damage to the collagen fibril structure and architecture. This study showed the 3-dimensional fibrous structure of the cemento-dentinal junction in human mandibular third molars, and suggested that interfibrillar adhesive substances are more important than the fibril intermingling for the cemento-dentinal attachment.


Asunto(s)
Cemento Dental/ultraestructura , Dentina/ultraestructura , Tercer Molar/ultraestructura , Cáusticos , Técnicas de Preparación Histocitológica , Humanos , Mandíbula , Microscopía Electrónica de Rastreo/métodos , Hidróxido de Sodio
20.
J Periodontal Res ; 36(5): 317-21, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11585119

RESUMEN

The cemento-dentinal junction was examined in human maxillary incisors, canines and premolars by scanning electron microscopy combined with NaOH maceration. The NaOH maceration was used to remove interfibrillar substances and to observe details of the fibrillar architecture. The teeth were half-sectioned longitudinally, demineralized and macerated for 3-4 days or for 10-14 days. In the 3-4 day-macerated specimens, longitudinal sections of the cemento-dentinal junction were examined. In the 10-14 day-macerated specimens, the cementum was detached and the inner cementum surface facing the cemento-dentinal junction was examined. Observations suggested that cemental fibrils intermingle with dentinal fibrils only in places at the cemento-dentinal junction in both acellular and cellular cementum. These structural features were consistent in all kinds of teeth investigated here. Using human molars, we have previously proposed that the adhesion of proteoglycans is a main factor for the cemento-dentinal attachment and that the fibril intermingling between dentin and cementum is an accessory or secondary factor. The present study suggests that this applies to other kinds of human teeth.


Asunto(s)
Cemento Dental/ultraestructura , Dentina/ultraestructura , Diente Premolar/ultraestructura , Tejido Conectivo/ultraestructura , Diente Canino/ultraestructura , Colágenos Fibrilares/ultraestructura , Técnicas Histológicas , Humanos , Incisivo/ultraestructura , Maxilar , Microscopía Electrónica de Rastreo , Hidróxido de Sodio , Raíz del Diente/ultraestructura
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