PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Root Resorption”

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 1,009 records · Page 56Linked to original sources

Cytotoxicity analysis of alendronate on cultured endothelial cells and subcutaneous tissue. a pilot study.

The use of alendronate, a bisphosphonate which is able to inhibit bone resorption, in order to prevent dental root resorption after tooth replantation would be of clinical relevance. However, this drug must be biocompatible to the periapical tissues. The aim of this study was to analyze the effect of an alendronate paste in polyethyleneglycol (2 g ml(-1)) on endothelial cells in culture (in vitro) and on rat subcutaneous tissue (in vivo). For the in vitro study the paste was applied on round glass coverslips that were immersed into confluent cell cultures (clone Cips). The cell viability percentages of these cultures were obtained 0, 6 and 12 h after contact with the substance. As control, cultures that received plain coverslips were used. This analysis was carried out in triplicate using the Trypan blue dye exclusion assay. For the in vivo study the paste was introduced into polyethylene tubes that were placed into the rat subcutaneous tissue. The rats were killed 7 and 14 days later; then, the tissue sections stained with hematoxylin-eosin were analyzed. In vitro, the alendronate caused a significant decrease in the cell viability in 6 h (P < 0.05) and 12 h (P < 0.01), when compared with the control cultures. In vivo the tissue response was exuberant and similar at the two experimental times. There was a necrosis in a comprehensive area in contact with the open end of the tube. Presence of micro-abscesses and intense inflammatory infiltrate in the hypoderm permeating the muscle fibers and fat lobules were observed. In conclusion, the alendronate paste in polyethylene glycol as used showed to be highly cytotoxic in vitro as well as in vivo.

Alendronate↗

Menkes disease: report of two cases.

Menkes disease is a rare, autosomal recessive disorder characterized by neuronal degeneration, abnormal hair, malformed connective tissue, mental retardation, and a life span of three years. Previously reported dental findings include a high arched palate, delayed eruption of secondary dentition, and open bite. The case of twin seven-year-old males with Menkes disease is presented, along with previously unreported dental findings of spindle-shaped root resorption patterns on the primary maxillary central and lateral incisors.

Child↗

[Histologic, ultramicroscopic, and microradiographic study of histiocytosis X lesions in the periodontium].

Examination under an optical microscope of a radiolucent mandibular lesion showed a proliferation of histiocytes. Upon further examination of electron micrographs, the lesion showed the presence of Langerhans cell granules, within the histiocytes, thus confirming the clinical diagnosis of Hand-Schüller-Christian's disease. Microradiographic study of the canine tooth and the surrounding alveolar bone shows alveolar and root resorption, as well as signs of osteomalacia.

Adult↗

Replantation of 400 avulsed permanent incisors. 1. Diagnosis of healing complications.

A material of 322 patients with 400 avulsed and replanted permanent teeth were followed prospectively in the period from 1965 to 1988 (mean observation period = 5.1 yrs). The age of the patients at the time of replantation ranged from 5 to 52 yrs (mean = 13.7 yrs and median = 11.0 yrs). Standardized patient records were used through the entire period in order to obtain valid data concerning the extent of injury and treatment provided. At the follow-up period, pulpal and periodontal healing were monitored by clinical examination, mobility testing and standardized radiographic controls. Thirty-two of the replanted teeth (8%) showed pulpal healing. When related to teeth with incomplete root formation, where pulpal revascularization was anticipated (n = 94) the frequency of pulpal healing was 34%. Periodontal ligament healing (i.e. with no evidence of external root resorption) was found in 96 teeth (24%). Gingival healing was found in 371 teeth (93%). During the observation period, 119 teeth (30%) were extracted. Tooth loss was slightly more frequent in teeth with incomplete root formation at the time of replantation than in teeth with completed root formation.

Adolescent↗

[Orthodontic movements and the periodontium: how far to go? A review of the literature].

The aim of this paper was to describe, with the help of recent research informations, the possible interactions between orthodontics and periodontics. It is well-known that the periodontal structures of a tooth play an important role during its orthodontic movement; this should therefore be considered before, during and after any orthodontic treatment. The theoretical basis of the usual difficulties are explained, as well as their clinical consequences. The particular problem of orthodontic movements in dentitions with reduced periodontal support has been stressed. A synoptic table summarizes the diagnostic steps and the clinical approach with the recommendations which seem, at the present time, to allow the preservation of the periodontal structures during orthodontic movement. Finally, the problem of apical root resorption is addressed in a specific chapter.

Adult↗

Periodontal repair in dogs: healing in experimentally created chronic periodontal defects.

A need exists for well-defined animal models to objectively evaluate surgical principles and a possible role for biochemical wound conditioning and biomaterials in promoting periodontal regeneration. To test an existing model for its usefulness in quantitative evaluation of periodontal wound healing, large supraalveolar periodontal defects were surgically created around the mandibular premolars (P2, P3, P4) in left or right jaw quadrants in 5 beagle dogs. The defects were exposed to the oral environment for 6 months and were then subjected to reconstructive flap surgery (chronic defects). Healing in these defects was compared to healing following reconstructive surgery in similar contralateral defects which had not been exposed to plaque and calculus (acute defects). The animals were sacrificed after a 4-week healing period and tissue blocks including teeth and surrounding structures were processed for histometric analysis. Mean defect height (+/- s.d.) for chronic and acute defects amounted to 4.6 +/- 0.3 and 4.4 +/- 0.4 mm, respectively. Mean connective tissue repair to the root surface in chronic defects amounted to 62% (range 49% to 74%) of the defect height. Mean connective tissue repair in the acute defects exceeded 94% of the defect height in 4 of the dogs, but amounted to only 48% in 1 dog. Regeneration of alveolar bone and cementum was limited under both experimental conditions. Root resorption was frequently encountered, whereas ankylosis was seen in only few teeth. This study indicates that healing may vary not only as a result of controlled experimental variables, but also due to differences in biological response between dogs or to fortuitous traumatic factors.(ABSTRACT TRUNCATED AT 250 WORDS)

Alveolar Bone Loss↗

Human intraosseous healing responses to the placement of tricalcium phosphate ceramic implants. II. 13 to 18 months.

Five intrabony lesions in a 40-year-old healthy, white female patient suffering with severe periodontitis were removed en bloc, 13 to 18 months after flap debridement and graft placement. At the time of debridement, the position of the gingival margin and the most apically located calculus were notched in the root to serve as reference points. All lesions received tricalcium phosphate ceramic implants, and the lesions healed uneventfully. The sites were professionally cleaned frequently during the experimental period. At the time of block removal, clinical measurements demonstrated gingival recession (average = 2.6 mm) and a gain in clinical closure (average = 2.3 mm). Histologic evaluation of step serial sections of these blocks showed limited presence of graft particles. The particles were surrounded by dense connective tissue. They did not induce inflammation, nor did they appear to enhance osteogenesis or cementogenesis. Closure of lesions was essentially done by a long junctional epithelium adhesion and limited evidence of new connective tissue--root attachment. In the 18-month specimen, active root resorption was seen immediately apical to the junctional epithelium at a site demonstrating significant inflammation in some sections. Fibrils apparently arising from the resorbing dentinal wall were seen in these sections. Serial sections of this site showed cellular cementum and functional fiber attachment at the resorption sites. These variations in resorption/repair/regeneration within the same surgical site were seen 18 months postsurgery and thus may reflect local tissue responses to inflammatory fluctuations rather than surgical sequellae.

Adult↗

Regeneration of calcitonin gene-related peptide immunoreactive nerves in replanted rat molars and their supporting tissues.

First maxillary right molars in 66 rats were elevated and replanted and the pulps allowed to regenerate for 1-90 days. The contralateral tooth served as control. Regeneration of nerves in the pulp and periodontium was studied by CGRP-immunohistochemistry and the avidin-biotin-peroxidase method. The pulp and periodontium of the controls were richly supplied with CGRP-labelled nerves. One day after replantation the pulp was completely devoid of CGRP-immunoreactive nerves. After 2 days, axon sprouts were present in the apical, regenerated pulp and in the periodontium. From 3-7 days CGRP-immunoreactive axons were regularly seen to have regenerated in front of the cellular inflammation in the pulp. After 10 days, the pulps were reinnervated up to the horns, although more sparsely than in the controls. From day 20-90 there was a marked divergence in pulpal healing: 17 pulps formed irregular postoperative dentine with a gradual increase in nerve density; 16 pulps remained sparsely innervated and were gradually replaced by bone. Root resorption was most extensive in the teeth with bone replacement of pulp. The soft tissue adjacent to extensive resorbing areas had many more CGRP-labelled axons than in the controls. The reinnervation of the regenerating pulp occurred at the same time as pulpal wound healing, but did not achieve the innervation density of the controls.

Animals↗

Spatial distribution of lead in the roots of human primary teeth.

Lead remains one of the most hazardous metals in our environment. The concentrations of lead in coronal dentine and enamel have previously been reported but limited information is available regarding lead levels in radicular dentine and cementum. This study reports the distribution of lead in 26 roots of 16 human maxillary primary teeth from seven individuals. In addition, calcium and phosphorous concentrations were also measured to detect any variations in the degree of mineralization in different regions of the roots. The mean lead concentration in these roots was 1.67 +/- 1.43 microg/g, which is comparable to other studies. In all cases there were higher lead concentrations in the apices of non-resorbed roots of primary maxillary teeth relative to middle and cervical regions. The findings reported here are of potential significance during the process of physiological root resorption whence periapical tissue may be exposed to higher levels of lead.

Calcium↗

pH changes at the surface of root dentin when using root canal sealers containing calcium hydroxide.

The purpose of this study was to investigate long-term pH changes in cavities prepared in root surface dentin of extracted teeth after obturation of the root canal with gutta-percha and a variety of sealers containing calcium hydroxide. After cleaning and shaping, root canals in 50 recently extracted, human single-rooted teeth were divided into five groups. Each of four groups was obturated with gutta-percha and either Sealapex, Sealer 26, Apexit, or CRCS, all of which contain calcium hydroxide. The remaining group served as the control and was not obturated with gutta-percha or sealer. Cavities were prepared in the facial surface of the roots in the cervical and middle regions. The pH was measured in these dentinal cavities at the initiation of the experiment, and 3, 7, 14, 21, 28, 45, 60, 90, and 120 days after obturation. Results indicate that the pH at the surface of the root does not become alkaline when calcium hydroxide cements are used as root canal sealers. Regardless of the sealer used, the observed pattern of pH change was not different from that seen in the control group of roots that were not treated with sealer. It is concluded that calcium hydroxide-containing cements, although suitable for use as root canal sealants, do not produce an alkaline pH at the root surface. If such a pH change is related to treatment of root resorption, these sealants do not contribute to this treatment.

Bismuth↗

Tooth resorption in the two-stage transplantation technique: a case report.

A case report of a two-stage canine transplant is presented in which circumstances appeared ideal for success. Storage of the tooth in a buccal pouch for six months precipitated extensive crown and root resorption. The prognosis for this approach to treatment of impacted canines indicates caution in its use.

Adolescent↗

Class II MHC antigen-expressing cells in the pulp tissue of human deciduous teeth prior to shedding.

The distribution and ultrastructure of the class II major histocompatibility complex (MHC) antigen-expressing cells in the pulp tissue of human deciduous teeth during the process of physiological root resorption was surveyed by histochemical and immunocytochemical methods using an anti-human leukocyte antigen (HLA)-DR-monoclonal antibody. Dental pulp was found to contain numerous HLA-DR-positive cells of various shapes; those showing a dendritic appearance were located mainly in the periphery of the pulp tissue, associated closely with the odontoblasts. The immunopositive cells sometimes extended their cytoplasmic processes into the dentinal tubules and increased in number in the areas affected by dental caries, attrition or restorative procedures, implicating their role in immunosurveillance. The immunopositive cells were located consistently at the pulp-dentin border during the stage of active resorption, adjacent to the preodontoclasts or odontoclasts, and covered the exposed dentin surface after the detachment of the odontoclasts until the onset of cementum formation. These data suggest that the HLA-DR-immunopositive cells in the coronal pulp of human deciduous teeth play an inductive role in the differentiation, migration and/or activation of the odontoclasts and cementoblast-like cells during the stages of tooth resorption.

Dental Pulp↗

Replantation of an avulsed incisor after prolonged dry storage: a case report.

Management of tooth avulsion in the permanent dentition often presents a challenge. Definitive treatment planning and consultation with specialists is seldom possible at the time of emergency treatment. Replantation of the avulsed tooth can restore esthetic appearance and occlusal function shortly after the injury. This article describes the management of a child with an avulsed maxillary permanent incisor that had been air-dried for about 18 hours. The replanted incisor retained its esthetic appearance and functionality 2 years after replantation, yet the long-term prognosis is not good because of progressive replacement root resorption.

Child↗

The effect of Emdogain gel on periodontal healing in replanted monkeys' teeth.

OBJECTIVE: We sought to histologically evaluate the effect of Emdogain gel on periodontal healing in monkeys' teeth undergoing delayed replantation. Study design Mature monkey teeth simulating avulsion were endodontically treated before extraction. Negative control teeth (group N = 10 roots) underwent immediate replantation, whereas the rest were bench-dried for 1 hour and treated in one of the following ways before replantation: the positive control teeth (group P = 12 roots) had no further treatment; group C teeth (4 roots) had the periodontal ligament removed; group D teeth (10 roots) were treated with Emdogain gel; group E teeth (6 roots) had the periodontal ligament removed before the application of Emdogain gel; and group F teeth (7 roots) had the periodontal ligament removed, the root surface conditioned, and Emdogain gel applied. Periodontal healing was evaluated after 16 weeks by undertaking histomorphometric analysis. RESULTS: The Kruskal-Wallis and Mann-Whitney U tests revealed that group N teeth had a statistically higher occurrence of complete healing than did all other groups, whereas group P was not significantly different in any of the healing categories from D, E, and F, the groups in which Emdogain gel was used. Group C teeth had a significantly higher occurrence of replacement root resorption than did the teeth in groups P and F-but were not significantly different from teeth in groups D and E. CONCLUSION: Emdogain gel did not appear to significantly reduce replacement resorption in monkeys' teeth that had undergone delayed replantation.

Acid Etching, Dental↗

Improving orthodontic results in cases with maxillary incisors missing.

This article has aimed at providing information on how to improve clinical orthodontic results in cases in which maxillary central and lateral incisors are missing. Different sections deal with (1) treatment approach and mechanics, (2) details in finishing, (3) modifications of clinical tooth crowns by special procedures (grinding, composite "corners," gingivectomy), (4) functional considerations and root resorption, and (5) retention.

Bicuspid↗

A finite element model of apical force distribution from orthodontic tooth movement.

This study was undertaken to determine the types of orthodontic forces that cause high stress at the root apex. A 3-dimensional finite element model of a maxillary central incisor, its periodontal ligament (PDL), and alveolar bone was constructed on the basis of average anatomic morphology. The maxillary central incisor was chosen for study because it is one of the teeth at greatest risk for apical root resorption. The material properties of enamel, dentin, PDL, and bone and 5 different load systems (tipping, intrusion, extrusion, bodily movement, and rotational force) were tested. The finite element analysis showed that purely intrusive, extrusive, and rotational forces had stresses concentrated at the apex of the root. The principal stress from a tipping force was located at the alveolar crest. For bodily movement, stress was distributed throughout the PDL; however, it was concentrated more at the alveolar crest. We conclude that intrusive, extrusive, and rotational forces produce more stress at the apex. Bodily movement and tipping forces concentrate forces at the alveolar crest, not at the apex.

Alveolar Process↗

Traumatic intrusion of permanent teeth. Part 2. A clinical study of the effect of preinjury and injury factors, such as sex, age, stage of root development, tooth location, and extent of injury including number of intruded teeth on 140 intruded permanent teeth.

A prospective study of 140 intruded permanent teeth was done to evaluate the following healing complications: pulp necrosis (PN), root resorption (surface, inflammatory and replacement resorption) (RR) and defects in marginal periodontal healing (MA). These complications were related to various preinjury and injury factors. Age appeared to be related to all three healing complications in that patients younger than 12 years had the lowest complication rate. Stage of root formation at the time of the injury was very strongly related to PN and MA, with immature root formation (i.e. incomplete root formation or completed root formation with wide open apex) having better prognosis than more mature root development. Lateral incisors showed significantly more defects in MA, a finding possibly explained by the observation that lateral incisors were more often involved in multiple intrusions compared to other teeth and noting that multiple intrusions had a significantly higher frequency of MA. An associated crown fracture with exposed dentin resulted in more frequent PN, a finding possibly related to bacterial invasion through dentinal tubules into an ischemic pulp. The presence of a gingival laceration added to both PN and MA. The extent of intrusion (in mm) showed some relation to both RR with intrusion 1-3 mm having the lowest frequency of RR, whereas PN and MA showed no significant relation to the extent of intrusion. Finally, multiple adjacent intruded teeth were more frequently involved in a significantly greater loss of interproximal marginal bone (MA) than single intrusions. In conclusion, the relationship between healing complications and preinjury and injury factors could generally be explained by better healing possibilities in teeth with immature root formation. A possible explanation for that could be the softer bone surrounding the tooth, whereby trauma to the periodontium might be diminished.

Adolescent↗