Subject(s)
Dental Bonding , Root Canal Filling Materials , Silicones , Barium Sulfate , Humans , Silicon Dioxide , SiloxanesABSTRACT
45Ca was injected into prenatal mice to study the calcium uptake by tooth germ cells. Both dental papillae, containing the odontoblasts, and the enamel organs were found to actively metabolized the labeled calcium. The maximum specific radioactivity occurred at 15 minutes after injection. The subcellular organelles (e.g. mitochondria) of the papillae were more active in metabolizing the labeled calcium whereas a large portion of the radioactivity of the enamel organ was found in a fraction containing the precalcified material. In fetal tooth germs, the rate of incorporation of labeled calcium into the precalcified material was slower than in the postnatal tooth germs since a large portion of the radioactivity remained in the soluble fraction.
Subject(s)
Calcium/metabolism , Tooth Germ/metabolism , Animals , Calcium Radioisotopes , Dental Papilla/metabolism , Enamel Organ/metabolism , Mitochondria/metabolism , Organoids/metabolism , RatsABSTRACT
Forty-five abscessed human mandibular primary molars with bifurcation radiolucency were subjected to a two-stage formocresol treatment of the pulp chamber. On the first appointment, an elliptical patch of buccal mucosa was removed. Bony defects varied from 2 mm. to more than 4 mm. in diameter. Periapical radiographs were used to record changes in bone development. Punch biopsy specimens were taken from the bifurcation area of some subjects from 2 weeks up to a year after surgical curettement. Biopsied tissue was studied by electron and light microscopy to examine wound healing of the bifurcation, revealing an early proliferation of fibroblasts with extracellular collagen fibers. Some of the fibroblasts exhibited an extensive network of rough endoplasmic reticulum, scattered free ribosomes, mitochondria, and other organelles which are normally observed in healthy fibroblasts. Histologic and clinical evaluation support the treatment tested for retention of previously abscessed primary molars.
Subject(s)
Curettage , Molar , Periodontal Abscess/physiopathology , Periodontitis/physiopathology , Tooth, Deciduous , Bacteria/cytology , Child , Child, Preschool , Collagen , Epithelium/anatomy & histology , Female , Formocresols , Humans , Male , Mouth Mucosa/anatomy & histology , Mouth Mucosa/physiology , Periapical Tissue/anatomy & histology , Periodontal Abscess/etiology , Periodontal Abscess/pathology , Periodontal Abscess/surgery , Pulpitis/microbiology , Pulpotomy , Wound HealingABSTRACT
Endosteal vitreous carbon implants are biocompatible and were well-tolerated by the alveolar process of dogs but were not accepted by the gingival margin and the mucosa. A continuous gingival recession with 2 to 3 mm sulcus depth was not similar to that around adjacent natural teeth. There was no epithelial attachment around the neck of vitreous carbon implants, and there was very little or no resistance to probing. The feasibility of using vitreous carbon as it presently exists for the maintenance and preservation of alveolar bone is unfavorable and should be revised. Endosteal vitreous carbon implants require more intense laboratory and clinical studies. Therefore, the practical value of the vitreous carbon implant is questionable, and further investigations are needed before vitreous carbon can be declared acceptable in clinical dental practice.
Subject(s)
Carbon , Dental Implantation, Endosseous , Periodontium/anatomy & histology , Alveolar Process/anatomy & histology , Animals , Ceramics , Connective Tissue/anatomy & histology , Crystallization , Dogs , Fibroblasts/cytology , Gingiva/anatomy & histology , Osteogenesis , Wound HealingSubject(s)
Alveolar Process/pathology , Bone Resorption/pathology , Osteoclasts/pathology , Periodontitis/pathology , Alveolar Process/ultrastructure , Animals , Epithelial Attachment/pathology , Haplorhini , Macaca mulatta , Microscopy , Microscopy, Electron, Scanning , Osteoclasts/ultrastructure , Osteogenesis , Periodontal Ligament/pathology , Tooth/pathology , Tooth Mobility/pathologyABSTRACT
Defects of the enamel include hypoplasia and hypomineralization. The cause can be local, systemic, or hereditary. A 14-year-old boy had type 4 hereditary hypoplastic enamel. The Nuva-Seal, Nuva-Fil acid-etch technique was used to restore the defect.
Subject(s)
Acid Etching, Dental , Composite Resins , Dental Bonding , Dental Enamel Hypoplasia/therapy , Dental Restoration, Permanent , Adolescent , Dental Enamel Hypoplasia/genetics , Humans , MaleABSTRACT
Incisor and molar tooth germs of albino rats sacrificed at the eighteenth and twentieth days in utero and one to seven days after birth were studied with light and electron microscopy. Observations of the various stages of tooth development in molars established that intramitochondrial granules in odontoblasts were comparable to the intramitochondrial granules of other hard tissue cells. These electron-dense deposits appeared in mitochondria in an appreciable number only when odontoblasts become engaged in dentin mineralization. When dentin mineralization was advanced the odontoblast mitochondria appeared devoid of these deposits. Mesenchymal cells and preodontoblasts of the pulp were not involved in this activity.
Subject(s)
Mitochondria/ultrastructure , Odontoblasts/ultrastructure , Tooth Germ/ultrastructure , Animals , Dentinogenesis , Incisor , Microscopy, Electron , Mitochondria/metabolism , Molar , Rats , Tooth Germ/metabolismABSTRACT
We attempted to study the nasal mucosa of children (both normal and diseased) under light microscopy followed by both scanning and transmission electron microscopy. Combined methods of microscopy are valuable tools in establishing the diagnosis and lead to a better understanding of disease and its management. For this reason we found it necessary to study the ultrastructural details of the cells of the nasal mucosa. Through scanning electron microscopy we studied the functional aspects and the nature of the surface of these cells. Ultrastructural details of these cells were studied with the aid of transmission electron microscopy.
Subject(s)
Nasal Mucosa/ultrastructure , Nose Diseases/pathology , Adolescent , Basement Membrane/ultrastructure , Child , Child, Preschool , Cilia/ultrastructure , Exocrine Glands/metabolism , Humans , Microscopy, Electron , Microscopy, Electron, Scanning , Mucus/metabolismABSTRACT
The average magnitudes of cellular displacements, superficial responses, and deep responses were less for specimens restored with ZOE than for Enamelite specimens at the 1 week postoperative period. Of 20 teeth treated, three abscesses were found in the 1 week Enamelite postoperative period when the remaining dentin was 0.3 mm. or less. This indicates the presence of ingredients that are toxic to the pulp when there is little remaining dentin or when the material is placed directly over an exposure. Teeth restored with Enamelite in the 6 week group had values comparable to the ZOE teeth for the same time period.
