Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Root Caries”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

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

At least 1,279 records · Page 71Linked to original sources
PubMedDate not supplied

Root growth and metal uptake in four grasses grown on zinc-contaminated soils.

Depth and area of rooting are important to long-term survival of plants on metal-contaminated, steep-slope soils. We evaluated shoot and root growth and metal uptake of four cool-season grasses grown on a high-Zn soil in a greenhouse. A mixture of biosolids, fly ash, and burnt lime was placed either directly over a Zn-contaminated soil or over a clean, fine-grained topsoil and then the Zn-contaminated soil; the control was the clean topsoil. The grasses were 'Reliant' hard fescue (Festuca brevipila R. Tracey), 'Oahe' intermediate wheatgrass [Elytrigia intermedia (Host) Nevski subsp. intermedia], 'Ruebens' Canada bluegrass (Poa compressa L.), and 'K-31' tall fescue (Festuca arundinacea Schreb.). Root growth in the clean soil and biosolids corresponded to the characteristic rooting ability of each species, while rooting into the Zn-contaminated soil was related to the species' tolerance to Zn. While wheatgrass and tall fescue had the strongest root growth in the surface layers (0-5 cm) of clean soil or biosolids, wheatgrass roots were at least two times more dense than those of the other grasses in the second layer (5-27 cm) of Zn-contaminated soil. When grown over Zn-contaminated soil in the second layer, hard fescue (with 422 mg/kg Zn) was the only species not to have phytotoxic levels of Zn in shoots; tall fescue had the highest Zn uptake (1553 mg/kg). Thus, the best long-term survivors in high-Zn soils should be wheatgrass, due to its ability to root deeply into Zn-contaminated soils, and hard fescue, with its ability to effectively exclude toxic Zn uptake.

Plant Roots↗
PubMed1984

Mineral flux of surface enamel and root surfaces in acidified gelatin gels.

Gels of crude gelatin were dialyzed to eliminate fluoride, and then acidified with 75 mM lactic and 25 mM acetic acid at pH 4.2 and interfaced with enamel and root surfaces in gel-surface ratio of 0.2 ml/0.15 cm2. Enamel and root surface to gel mineral flux was reduced by initial inclusion of 0.5 and 1.0 mM fluoride with 2.5 mM calcium and 1.5 mM phosphate in gels at pH 4.2. Inclusion of 0.25 mM fluoride in the gels without added mineral ions had no effect in the first 22-day interface. The 0.25, 0.5 and 1.0 mM fluoride remarkably increased remineralization in a second 12-day interface. This indicated that the first fluoride exposure initiated formation of fluorapatites in the enamel which required a lower degree of gel saturation for enhanced remineralization in the second acid exposure. Fluoride had the same effect, but greater effectiveness on enamel than root-surface remineralization. Gels of crude gelatin may contain sufficient mineral ions to alter remineralization-demineralization of enamel and root surface.

Acetates↗
PubMed2004

Density of dentinal tubules affects the tensile strength of root dentin.

OBJECTIVES: The aim of this study is to count the dentinal tubules in the coronal and middle-apical third of root dentin of teeth extracted due to the progression of periodontal disease, and to compare the Ultimate Tensile Strength (UTS) of the same areas. The research hypothesis was that root dentin areas with different densities of dentinal tubules would also show different UTS values. METHODS: From 10 caries free maxillary central, lateral incisors and canines, extracted for periodontal reasons from three patients, cylindrical specimens approximately 10 mm long were prepared parallel to the long axis of the root and then divided into two parts using a low speed diamond saw one from the coronal third of the root, (Group 1) and one from the middle-apical third of the root (Group 2). The density of the dentinal tubules of the specimens of the two groups was measured by means of a scanning electron microscope and the UTS of the specimens was measured by a microtensile test. One way ANOVA was used to assess the effect of specimen location (coronal specimens vs. middle-apical specimens) on UTS. The differences in the density of dentinal tubules between coronal and middle-apical specimens were also subjected to statistical analysis using one-way ANOVA. RESULTS: UTS values of middle-apical specimens were found to be significantly (p < 0.05) higher than those of coronal specimens. The results of the one-way analysis of variance showed that the number of dentinal tubules of the samples from the coronal part of the root groups was significantly higher than that of samples from the middle-apical part (p < 0.05). SIGNIFICANCE: These results suggest that high values of tensile strength of the dentin are associated with low densities of dentinal tubules and that apical areas of root dentin are more resistant to tension than coronal ones.

Analysis of Variance↗
PubMed2004

Safety parameters for pulp temperature during selective ablation of caries by KTP laser in vitro.

OBJECTIVE: To define the optimal parameters of KTP laser irradiation during a selective caries removal. MATERIALS AND METHODS: Twelve decayed human teeth, recently extracted were used. Their root canals were prepared for insertion of a thermocouple probe into the pulp chamber. The demineralized tissues were colored by Acid Red 52 before proceeding to different conditions of irradiation. RESULTS: Pulpal temperature increases (below 3 degrees C) were found under the following parameters with 15 sec of continuous lasing: 400 mWatts, 0.10-msec pulse width, PRR <50 Hz for efficient caries removal. A resting time average of 70 sec was necessary to allow pulp temperature to get back to its baseline. CONCLUSION: KTP laser can be used safely and without any pulp over-heating under certain irradiation conditions.

Body Temperature↗
PubMed1989

Pattern of dental caries in an adult rural population.

A study was conducted amongst 1,131 randomly selected persons aged 15-65 years in a rural area of Kenya, having minimal access to dental care. A relatively low prevalence of frank cavitation was found in the 15- to 24-year-old cohort, but in the older age groups over 80% were so affected. Caries in the youngest cohort was characterized by a predominance of enamel lesions. At the age of 25-34 years, however, involvement of pulpal tissues and loss of teeth due to caries was more common, and this age group exhibited the largest number of dentinal lesions. The 35- to 44-year-old cohort exhibited fewer enamel and dentinal lesions, but more pulpally involved lesions and more extracted teeth. In the group aged 45-54 years, enamel and dentinal lesions were less common, and at the age of 55-65 years, such lesions were less common in comparison to their occurrence in younger cohorts. The 55- to 65-year cohort could generally be characterized as having larger numbers of root surface lesions, lesions involving the pulp, and extracted teeth. Root surface lesions were principally associated with age over 35 years. In all age groups caries exhibited a skewed distribution, most of the lesions occurring in a minority of individuals. This study demonstrates that caries activity continues throughout life and is not a phenomenon confined to any one period of life.

Adolescent↗
PubMed1980

Dentin dysplasia type I: a scanning electron microscopic analysis of the primary dentition.

Dentin dysplasia type I (DD-I) is a rare autosomal dominant disorder which affects both the deciduous and permanent dentitions. The affected deciduous and permanent teeth have short conical roots with sharp, apical constrictions and frequently periapical radiolucencies in the absence of caries. Apical to a thin layer of normal coronal dentin are large, calcified, dentin masses which nearly obliterate the pulp chamber and canals. Presented here are light microscopic and scanning electron microscopic observations of deciduous teeth from three unrelated persons with the disorder. In general, the deciduous teeth had (1) normal enamel, (2) a thin layer of normal dentin adjacent to the dentinoenamel junction, (3) a crescent-shaped pulpal remnant below the normal dentin, (4) dysplastic dentin masses (ranging from atubular to a few small tubules) between which are spaces presumed to previously have contained smaller remnants of the original mesenchymal dental papilla, and (5) root dentin, which is dysplastic throughout. The SEM-defined phenotype, however, was noticeably variable among all three persons. Based on the current concepts of tooth morphogenesis, it is most likely that the abnormal root morphology of DD-I teeth is secondary to the abnormal differentiation and/or function of the ectomesenchymally derived odontoblasts.

Adult↗
PubMed1986

Quantitative comparisons of potentially cariogenic microorganisms cultured from noncarious and carious root and coronal tooth surfaces.

Potentially cariogenic microorganisms cultured from noncarious and carious root and coronal (enamel) surfaces were quantitatively compared in patients 22 to 84 years of age (mean, 52 years). We collected 150 plaque specimens from 26 in situ teeth with initial root lesions and from 25 extracted teeth with advanced root lesions. The frequencies of isolation of Streptococcus mutans, Actinomyces viscosus, and Lactobacillus spp. were, respectively, 94, 72, and 51% at the noncarious root site; 98, 71, and 54% at the root lesion; 84, 61, and 44% at the noncarious enamel site; and 100, 66, and 90% at the enamel lesion. The streptococci made up the largest mean proportion of the total anaerobic cultivable microflora, ranging from 31.2% at the noncarious enamel site to 37.6% at the root lesion, while S. mutans varied between 18% at the noncarious enamel and root surfaces and approximately 24% at both the enamel and root lesions. The proportion of actinomyces ranged from 12.3% at the root lesion to 23.6% at the noncarious root site, while A. viscosus varied from 7.8% at the root lesion to 15.1% at the noncarious root site. The largest mean proportion of lactobacilli (4.2%) was recovered at the enamel lesion site. Proportions of Candida spp. made up less than 0.1% at all sites. Proportions of microorganisms did not differ significantly between noncarious enamel and root sites, but the noncarious coronal and root sites had higher (P less than 0.05) proportions of actinomyces than did the root lesion. Also, enamel lesions had a greater (P less than 0.05) percentage of Lactobacillus spp. than did root lesions. The number of streptococci recovered from the root lesion was greater (P less than 0.01) than the number of actinomyces at the same site. S. mutans was recovered from initial root lesions in greater numbers (P less than 0.001) than were actinomyces and lactobacilli. The number of S. mutans recovered at the initial root lesions was greater (P less than 0.01) than that recovered from the advanced root lesions.

Actinomyces↗
PubMed2006

Evaluation of odontological assistance to soldiers going on a mission, and prognostication of their odontological problems.

The aim of the study was to evaluate the condition of the oral cavity in soldiers going on a military mission, the level of odontological assistance to them, and to prognosticate possible odontological problems during the mission period. We studied 50 soldiers going on a military mission in Iraq. During the study we applied odontological examination and panoramic imaging. We found that soldiers' teeth were treated, and they received comprehensive odontological assistance: 18% of soldiers had their teeth restored with single crowns and bridges, and 56% of soldiers had underwent endodontic treatment of their teeth. During the radiological examination we diagnosed individual cases of dental caries on the contact surfaces of teeth, and determined the level of the filling of root canals of endodontically treated teeth and the relationship of this level with radiological changes in apical periodontium. 67.3% of teeth had incompletely filled root canals, and radiological changes in their apical periodontium were reliably more frequent (80.6%) than in the apical periodontium of teeth with completely filled root canals (19.4%) (p<0.001). Of significant concern is the fact that frequently teeth with incompletely filled root canals and apical periodontal damage are restored using radical post-core and crowns. Radiological examination showed that in teeth with signs of chronic apical periodontitis and insufficient quality of filling, the condition may become more acute and cause odontological problems. A part of odontological problems in soldiers may be caused by incorrect position of the third molars in the jaw and possible aggravated eruption of these teeth.

Adult↗
PubMed2005

[Endodontic treatment of primary teeth. Pulp exposure and pulp necrosis].

With management of the deep caries in primary teeth we have to take account into the coping strategies of the patient and the state of the development of the dentition. That's why in most cases a root canal treatment of primary incisors or even a pulpotomy is not indicated. Often Intellectual Decision Not To Restore is a good alternative for treatment of deep caries in primary incisors. In deep caries lesions of primary canines and molars preferably minimal invasive techniques as indirect pulp capping are performed. In case of a exposure, the dentist can choose between several types of treatment. Improved techniques have lead to clinical satisfying results of the calcium hydroxide pulpotomy. A partial pulpotomy is if possible the treatment of choice. A resin modified glass ionomer cement is used to cover the pulp wound because it has good sealing properties and it is easy to handle. To limit the burden in young children a root canal treatment in primary teeth is seldom indicated. Overfilling with calcium hydroxide in root canal treatment of primary teeth never causes problems.

Child↗
PubMed1994

[A longitudinal study of tooth exfoliation and dental caries in adults in Gucheng village].

In order to observe the Age-Related changes in dental health conditions, we selected Gucheng village, a rural area of Beijing as a surveillance place for our longitudinal study. 575 persons in different age groups were examined in 1984 and 507 persons were reexamined in 1989. The rate of reexamination was 86.4%. During the 5-year period, 0.3-1.8 teeth were missing in 20-40 years old groups and 2.8-5.5 teeth were missing in 50-70 years old groups. Beyond 60 years old groups more than 43% original remaining teeth were missing or present as residual roots. More than 10% original healthy teeth were decayed and more than 90% original caries teeth became aggravated in elderly group within 5 years. This study indicates that the incidences of tooth mortality and dental caries are much higher in elders than in young adults.

Adult↗
PubMed1996

[Differential diagnosis of resorptive tooth diseases and caries].

Feline Odontoclastic Resorptive Lesions (FORL, previously known as "neck lesions") on cat teeth are compared to caries and differentiated with the use of new methods. Radiological examination reveals typical odontoclastic resorptive processes, which take place at the dental root and at the periodontium. These lesions demonstrate the destruction on the desmodontium and the following ankylosing reaction. The rhodamine B stain which is selective for caries, stains regions which are softened by caries in a dark red way. Fuchsin/Acetic-Light Green stained histological preparations demonstrate the resorptive lacunae, resorptive lagoons and resorptive canals. Giant cells with multiple nuclei and reparative cementum can also be shown with the same stain. Hardness measurements using a Knoop diamond (KHN Knoop hardness number) give information about the degree of hardness of the different tissues. Electron microscopic investigations are performed to show the dentinal tubules and allowing the differentiation between FORL and caries. Since FORL also has been found in wild cats we deduced that alimentation has no effect on the pathogenesis of the disease.

Animals↗
PubMed1976

Endodontics and the irradiated patient.

With increasingly larger numbers of irradiated patients in our population, it seems likely that all denists will eventually be called upon to manage the difficult problems that these patients present. Of otmost concern should be the patient's home care program and the avoidance of osteroradionecrosis. Endodontics and periodontics are the primary areas for preventing or eliminating the infection that threatens osteoradionecrosis. Endodontic treatment must be accomplished with the utmost care and maximum regard for the fragility of the periapical tissues. Pulpally involved teeth should never be left open in an irradiated patient, and extreme care must be taken with the between-visits seal. If one is called upon for preradiation evaluation, routine removal of all molar as well as other compromised teeth should be considered. Attention should be directed to the literature for further advances in the management of irradiated patients.

Dental Caries↗
PubMed2002

Fracture strength after dynamic loading of endodontically treated teeth restored with different post-and-core systems.

STATEMENT OF PROBLEM: Prefabricated metal and ceramic posts can be used with direct or indirect cores as an alternative to the conventional cast post and core. It is unclear how the fracture strength of zirconia posts with composite or ceramic cores and titanium posts with composite cores compares to the fracture strength of gold posts and cores after dynamic loading. PURPOSE: This study compared the fracture strength of endodontically treated, crowned maxillary incisors with limited ferrule length and different post-and-core systems after fatigue loading. MATERIAL AND METHODS: Sixty-four caries-free, human maxillary central incisors were divided into 4 groups. After root canal treatment, Group 1 was restored with titanium posts and composite cores, Group 2 with zirconia posts and composite cores, and Group 3 with zirconia posts and heat-pressed ceramic cores. Teeth restored with cast-on gold posts and cores served as the controls (Group 4). Teeth were prepared with a circumferential shoulder including a 1 to 2 mm ferrule; all posts were cemented with an adhesive resin cement, restored with complete-coverage crowns, and exposed to 1.2 million load cycles (30 N) in a computer-controlled chewing simulator. Simultaneous thermocycling between 5 degrees C and 55 degrees C was applied for 60 seconds with an intermediate pause of 12 seconds. All specimens that did not fracture during dynamic loading were loaded until fracture in a universal testing machine at a crosshead speed of 1.5 mm/min; loads were applied at an angle of 130 degrees at the incisal edge. Fracture loads (N) and modes (repairable or catastrophic) were recorded. The Kruskal-Wallis test was used to compare fracture loads among the 4 test groups. Analyses were conducted both with and without the specimens that failed during the chewing simulation. A Fisher exact test was performed to detect group differences in fracture modes. A significance level of P<.05 was used for all comparisons. RESULTS: The following survival rates were recorded after the chewing simulation: 93.8% (Group 1), 93.8% (Group 2), 100% (Group 3), and 87.5% (Group 4). The median fracture strengths for Groups 1 to 4 were 450 N, 503 N, 521 N, and 408 N, respectively. No significant differences were detected among the groups. The use of zirconia posts resulted in a nonsignificant lower number of catastrophic root fractures. CONCLUSION: Within the limitations of this study, the results suggest that zirconia posts with ceramic cores can be recommended as an alternative to cast posts and cores. If a chairside procedure is preferred, zirconia or titanium posts with composite cores can be used. Clinical trials are required to verify these in vitro results.

Ceramics↗
PubMed1983

Epidemiology, etiology, and prevention of multiple sclerosis. Hypothesis and fact.

Slow, retrograde seepage of ionic mercury from root canal or Class V amalgam fillings inserted many years previously, recurrent caries and corrosion around filling edges, and the oxidizing effect of the purulent response may lead to multiple sclerosis in middle age. Epidemiologic studies of MS consistently reveal more neurological disease in the north, inferentially because there may be less caries and therefore fewer fillings done in the south. Clinical and epidemiologic data also suggest that a second heavy metal, lead, may operate almost interchangeably with mercury. Possibly, cases of unilateral MS derive from mercury-amalgam fillings in ipsolateral teeth, whereas the generalized disease may result from ingestion or inhalation of volatile mercury or exhaust fumes of lead additives to gasoline. The forensic and preventive-medical challenge is to identify, monitor, and resolve questions of hidden heavy metal hazards in a high technology society, especially those of lead and mercury. Further clinical-epidemiologic and basic science studies of heavy metal assays in whole blood, CNS tissues, packed cells, and serum are warranted. Prevention awaits further testing of the hypothesis and experience with substitute filling materials.

Climate↗
PubMed1985

Oral health in a long-term care institution equipped with a dental service.

The oral health and medico-dental status of 250 mostly elderly residents of a long term care institution were assessed by examination and a review of medical records. In addition, attitudes to dental care, dental experiences, and demands for care were solicited from those who could participate in an interview. There were no dental complaints from 70% of those interviewed. The complaints most frequently reported were difficulties with mouth dryness, hygiene, and chewing. Natural teeth remained in at least one jaw in 30% of the 245 residents examined. Dental caries was present in 78% of this dentate group, with coronal and root lesions equally prevalent. Gingival bleeding was also common in this group and 29% had deep periodontal pockets. Nearly 50% of the mandibular dentures and 25% of the maxillary dentures examined were inadequate. Mandibular dysfunction occurred in 25% of the population and was more frequent in the dentate group. Oral mucosal pathoses were rare. No correlation was found between the systemic health and the oral health of the residents. There was a need to improve the oral hygiene of most of those examined. Less than 20% of the denture wearers would have benefitted from treatment and 10% of those with defective dentures were considered unsuitable for treatment. In contrast, 60% of those with natural teeth required restorations and 36% needed one or more teeth removed. Very few urgent needs were seen. An inter-examiner accumulative inconsistency of 11% was measured between the three examiners, and a third of the assessments made of periodontal status were contradictory.

Aged↗