PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Tooth Apex”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,153 records · Page 64Linked to original sources
PubMed1980

[Growth of the tooth root after radiation--an animal experimental study].

The extent to which root growth and tooth eruption can be influenced by irradiation trauma was studied in beagle dogs. A cobalt 60 teletherapy apparatus with various dosages between 600 rad and 2400 rad was used to inflict the trauma on the maxilla and mandible. The results showed that the delay in tooth eruption was dependent on the dosage, but erruption could not be hindered. Longitudinal growth of the roots of irradiation, independent of the level of the dose. The periodontal fibers were normally aligned as with healthy teeth; the apex was formed predominantly by surplus cellular cement.

Animals↗
PubMed1977

Development and size of the teeth of Macaca mulatta.

A cross-sectional sample of 151 skulls from Macaca mulatta of known age and similar rearing in U.S. Primate Centers was analyzed to determine age-related "norms" of stages of development and size of teeth. The stages of development from the follicle of a deciduous incisor in the fetus to completion of the root with apex closed of the permanent third molar were related to age. The age range observed for eruption of each tooth was noted and related to its stage of development. The crown of each erupted tooth was found to be completely developed, but growth of its root continued for a longer, indeterminate period. When a deciduous tooth was exfoliated, the crown of the permanent successor was found to be completed and root growth had begun. Measurements of both mesiodistal and faciolingual diameters and of crown length of the teeth in situ and of total length and root length on roentgenograms were examined for sexual dimorphism. The faciolingual diameter of the deciduous mandibular second incisor and of both second molars showed the greatest sexual dimorphism among both diameters of all deciduous teeth. The mesiodistal and faciolingual diameters of the mandibular premolars were found to be the best dimensions in discriminant functions for identifying sex in the absence of permanent canines.

Age Factors↗
PubMed1991

Relation of pre- and intraoperative factors to prognosis of posterior apical surgery.

The relation of preoperative and intraoperative factors to the prognosis of apical surgery was studied in 136 premolar and molar roots. The evaluated factors were: clinical signs and symptoms, size of the periapical lesion, root canal obturation, tooth restoration, apical retrofilling, and the operating surgeon. A significantly higher success rate was found in roots obturated 2 mm or shorter of the apex, in roots without post restoration, and after retrofilling of roots with apparently well-condensed obturation. The prognosis differed significantly following treatment by various operators but was unrelated to their experience.

Apicoectomy↗
PubMed1999

Endodontic treatment of immature tooth with dens invaginatus: a case report.

The endodontic treatment of a dens invaginatus in an immature permanent upper lateral incisor of a 9-year-old boy is presented. Root canal treatment was performed using calcium hydroxide paste as a temporary root canal filling in order to achieve apexification. This was replaced after closure of the apex with a final root canal filling using gutta-percha and AH 26 as the sealer. The follow-up radiographic control demonstrated the effectiveness of nonsurgical treatment in a case of incomplete root formation in a tooth with dens invaginatus.

Calcium Hydroxide↗
PubMed1990

[Tooth movement of an impacted lower 2nd premolar in the root developmental stage--a follow-up radiographic observation on the root formation].

A 9 year old girl presented an impacted lower right 2nd premolar which not only was in horizontal position, but its crown was directed lingually. As a lower right 2nd premolar was in such a position that normal eruption was impossible, the deciduous predecessor was extracted at 9 years of age, and then sufficient space had been created for the lower right 2nd premolar to be erupted, and the eruption of it was observed for about 2 years. 2 years later, radiographic indication showed that no spontaneous eruption of a lower right 2nd premolar was to be expected. At 11 years of age, surgical exposure and traction of a lower right 2nd premolar was attempted. When the lower right 2nd premolar was upright, its root formation was in the 1st stage of root developmental stages according to Moorrees et al. Follow up radiographic observations on surgical exposure and traction of a lower right 2nd premolar 3 years later revealed the following results: 1. The root development went on to amount to about 90 percent of the root formation of the other tooth concerned without the curvature of the root. 2. Lamina dura and periodontal space were normal. The continued root formation was narrowing the root apex and the pulpal tissue of apical foramina was continuous with the periodontal space surrounding the root. 3. Bone deposition occurred at the alveolar crest and the latter was recontoured normally. The interdental and inter-radicular trabecula were good. As based on these results, normal development of the root of a lower right 2nd premolar with normal periodontium can be anticipated. Clinically, the lower right 2nd premolar had completely erupted and was in normal position on the arch and in occlusion. Color, vitality and mobility were normal. Periodontal support was good. The above-mentioned findings give support to the possibility that "early treatment" enables the impacted tooth to correct.

Bicuspid↗
PubMed2007

Margin failures in brittle dome structures: relevance to failure of dental crowns.

Margin cracks in loaded brittle dome structures are investigated. Dome structures consisting of glass shells filled with polymer resin, simulating the essential features of brittle crowns on tooth dentin, provide model test specimens. Disk indenters of diminishing elastic modulus are used to apply axisymmetric loading to the apex of the domes. Previous studies using hard indenters have focused on fractures initiating in the near-contact region of such specimens, including radial cracks at the glass undersurface directly below the contact axis. Here, we focus on fractures initiating at the remote support margins. Margin cracks can become dominant when loading forces are distributed over broad contact areas, as in biting on soft matter, here simulated by balsa wood disks. Cracks preinitiated at the dome edges during the specimen preparation propagate under load around the dome side into segmented, semilunar configurations reminiscent of some all-ceramic crown failures. Finite element analysis is used to determine the basic stress states within the dome structures, and to confirm a shift in maximum tensile stress from the near-contact area to the dome sides with more compliant indenters.

Crowns↗
PubMed1999

Effect of repeated orthodontic treatment on the dental and periodontal tissues of the rat incisor.

This study evaluated the response of treated teeth to renewed orthodontic force. Thirty female rats (201 +/- 2.7 g) were divided into groups A and B. Linguointrusive loads (20.58 +/- 1.88 g) generated by springs were applied to the lower left incisor for 2 weeks and then removed to allow recovery during 27 weeks (group A). Identical loading was then repeated in group A and applied as primary treatment in group B. Five animals from each group were killed with the springs in situ (A-1 and B-1), while the remaining 20 animals were killed after a 3-month recovery (A-2, B-2). The decalcified incisors were cross-sectioned serially (2 microm), and the distance of each section from the apex was computed. Dental and periodontal injuries were evaluated by light microscopy and plotted according to their location on the tooth axis. The intrusion of the teeth in group A-1 was significantly greater, whereas recovery of the normal eruption rate in group A-2 was significantly slower compared with groups B-1 and B-2. The histopathologic lesions in groups A-1 and B-1 did not differ. However, group A-2 showed a higher frequency of injured enamel organ, tissue infiltration by inflammatory cells, necrotic areas, and dentin resorption than group B-2. Initial orthodontic loading had a detrimental effect on the ability of the periodontal and dental tissues to cope with, and to recover from, repeated stress, probably because of a decrease in the number of periodontal fibroblasts and damage to the dentin-protecting cementoblastic layer.

Animals↗
PubMed2001

[Reparation and revision 3. Perforations during root canal treatment].

Iatrogenic perforations from the pulp cavity towards the periodontium result in complications that often lead to root or tooth removal. Identification of perforations is possible by direct observation of bleeding, indirect bleeding assessment using paperpoints, radiography and an apex locator. Successful treatment depends mainly on immediate sealing and prevention of infection. Several factors affect the achievement of these goals, such as time of occurrence, size and location of the perforation and the lability of the repair material to seal the lesion. An overview is presented of diagnosis, prognosis and non-surgical treatment of perforations.

Dental Pulp Cavity↗
PubMed2004

Odontogenic infections. Complications. Systemic manifestations.

The term, odontogenic infection refers to an infection that originates in the tooth proper or in the tissues that closely surround it; said infection then progresses along the periodontia down to the apex, involving periapical bone and from this area, it then spreads through the bone and periosteum towards near-by or more distant structures. The relevance of this type of infection lies in that it can cause infections that compromise more distant structures (via direct spread and distant spread), for example, intracraneal, retropharyngeal and pulmonary pleural infections. Dissemination by means of the bloodstream can lead to rheumatic problems and deposits on the valves of the heart (endocarditis), etc. The conditions or factors that influence the spread of infection are dependent on the balance between patient-related conditions and microorganism-related conditions. The virulence of the affecting germs is dependent upon their quality and quantity and is one of the microbiological conditions that influences the infection. It is this virulence that promotes infectious invasion and the deleterious effects the microbe will have on the host. Patient-related conditions include certain systemic factors that determine host resistance, which may be impaired in situations such as immunodeficiency syndrome or in brittle diabetes, as well as local factors that will also exert their impact on the spread of the infection.

Brain Abscess↗
PubMed1991

[A case of infected left atrial myxoma].

A rare case with infected left atrial myxoma is described. A 52 year-old male was admitted to our hospital because of pain and redness in the left forearm. He has had a history of fever and treatment with antibiotic after pulling out his tooth for two months. At admission, the temperature was 37.4 degrees C. A systolic ejection murmur was heard at the apex on auscultation. Initial investigation of blood showed infective signs. Ultrasonics and angiography revealed a embolus in the left brachial artery at the bifurcation of the radial artery and the ulnar artery. Echocardiography showed the typical feature of a large left atrial myxoma with vegetation. Embolectomy was performed. At the next day, the left atrial myxoma was removed and mitral valve with vegetation was replaced with a prosthetic valve. On microscopic examination, colonies of gram-positive cocci were seen in the thrombus on the typical myxoma. After treatment with antibiotics for six weeks, the patient was discharged from the hospital. He remains asymptomatic for ten months after the operation. Only 12 cases of infected left atrial myxomas have been reported previously in the world.

Bacterial Infections↗
PubMedDate not supplied

The fusion of three primary incisors: report of case.

The occurrence of a fusion of three primary incisors is rare. A two-year-old Japanese girl was brought to the pediatric dental outpatient clinic, Tokyo Dental College, to receive a caries-prevention treatment. The fused tooth consisted of the maxillary primary central incisors and right maxillary lateral incisor. Primary left lateral incisor erupted normally and the other primary teeth were erupted. The radicular pulp chambers were fused into one for three fourths of the length from the apex, and only one root. The hair and skin of the patient appeared normal and no systemic abnormality or congenital disease was noted in the medical history of the patient and her family. The occurrence of a three-tooth fusion, and no supernumerary tooth was confirmed.

Child, Preschool↗