PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Tooth”

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 109 records · Page 6Linked to original sources
PubMed1998

[Effects of pregnancy on orthodontic tooth movements: effects of progesterone on orthodontic tooth movements in pregnant rats].

This study evaluated the periodontal responses and progesterone changes to orthodontic tooth movements in pregnant rats. Adult female Sprague-Dawley rats were separated into two groups: non-pregnant and pregnant. All rats were treated with fixed orthodontic appliances that moved the upper incisors in a distal direction during 10 days. At the end of the experiment, the periodontal tissues were examined histologically and immunohistochemically (ABC method). The results showed that in the histological examination of the tension sides of the upper incisors, the bone formation was more obvious in the pregnant group than that in the non-pregnant group. In the immunohistochemical staining, the osteoblasts were positive-stained cells and they exhibited deeper stain and higher percentage in the pregnant group. In a conclusion, the progesterone influences the periodontal reconstruction on orthodontic tooth movements in pregnant rats and may be helpful in alveolar bone formation, which suggests that orthodontic treatments in pregnant patients may not be so harmful as people thought before.

Animals↗
PubMed1994

[Variations of pathological tooth loss with special reference to tooth erosion--apropos of a case].

Importance of tooth surface loss has increased in dental practice. It is difficult to determine aetiological factors and the exact diagnosis, because the symptoms are often combined. The aim of the present study was to summarise the most important factors of tooth surface loss, mainly of erosion which is a frequent form. Reviewing the literature aetiological factors, symptoms, differential diagnostic problems and therapeutic advice are discussed. Prevention, early diagnosis and treatment are very important in these patients.

Adult↗
PubMed1984

Tooth loss and tooth retention in a multitribal group of Bantu-speaking South African blacks: a study on 500 dry mandibles.

Tooth loss and tooth retention in adult South African Bantu-speaking Negroes were studied from data derived from 500 dry mandibles. The tribe, sex, and stated age of the specimens were available. Mandibles were equally distributed over the third to seventh decade of life. The presence of dental units was recorded and analysed within and between decade age groups. The mandibles carried a total of 5,459 dental units. Between the third and fourth decades of life and between the sixth and seventh decades, the reduction of the frequency of dental units was mild and statistically not significant. It was, however, severe and significant between the fourth and fifth, and the fifth and sixth decades. In the third-decade group, most teeth were found in the anterior region with a tendency to diminish in number posteriorly. After the third decade there was a definite persistence of first premolars and canines with significant tendency toward loss of teeth anterior and posterior to them. Only the incisors and third molars showed significant reduction in number from the third to the fourth decade. The reduction of all teeth was statistically significant later, until the sixth decade of life. Although there was loss of teeth from the sixth to the seventh decade, it was not significant for any of the homologous dental units. There is a possibility that some dietary differences existed between the older subjects (50-70 years old) and the younger ones (20-49 years old) which may have had some influence on the results.

Adult↗
PubMed2001

Survival of Dicor glass-ceramic dental restorations over 16 years. Part III: effect of luting agent and tooth or tooth-substitute core structure.

STATEMENT OF PROBLEM: The influence of different types of restorative design features on the long-term survival of Dicor glass-ceramic restorations is only partially understood. PURPOSE: This study examined the effect of different types of luting agents and preparation core structures on the survival of Dicor glass-ceramic restorations functioning in vivo. MATERIAL AND METHODS: A total of 1444 Dicor glass-ceramic restorations were placed on the teeth of 417 adults. Failure was defined as a restoration that required remake because of material fracture. The survival of restorations of different types, with different luting agents and preparation core structures, was described with Kaplan-Meier survival functions. The significance of differences in survival between different tooth or tooth-substitute preparation core structures and different luting agents was determined with the log-rank test. RESULTS: The probability of survival of a typical acid-etched Dicor restoration luted to gold preparation core structures was 91% at 16 years compared with 75% for dentin preparation core structures (P<.01). The survival of acid-etched Dicor restorations luted to dentin preparations was significantly better than nonacid-etched restorations luted to dentin. Acid-etched Dicor restorations luted with resin composite exhibited a more favorable survival function than those luted with glass ionomer (P<.01) and zinc phosphate (P<.05). Differences between restorations luted with glass ionomer or zinc phosphate agents were not significant. CONCLUSION: Acid-etched Dicor restorations luted to gold preparation core structures exhibited significantly better intraoral survival than restorations luted to dentin. Acid-etched Dicor restorations survived better than nonacid-etched restorations when luted to dentin preparations. Acid-etched Dicor restorations luted with resin composite exhibited more favorable survivor functions than restorations luted with glass ionomer or zinc phosphate agents.

Acid Etching, Dental↗
PubMed1998

Tooth and tooth surface survival rates in birth cohorts from 1965, 1970, 1975, and 1980 in Lahti, Finland.

Differences in the tooth and tooth surface survival rates between four cohorts born in 1965, 1970, 1975, and 1980 were analysed in a historical cohort study including data on the permanent teeth of children aged 5-7 years at baseline and 19 years at the end of the study. A statistically significant reduction in caries occurrence in fissured surfaces in the three oldest cohorts was seen during the 3 years after the eruption of the teeth. Caries occurrence in the cohorts born in 1975 and 1980 did not differ from each other. The occurrence of caries in smooth surfaces was low in all age cohorts. Therefore, despite a systematic decrease in caries occurrence towards the younger cohorts, no significant differences were found between the cohorts in smooth surface decay. After the 3 first posteruptive years, practically no differences in survival rates between the cohorts were observed. In the two youngest cohorts, the figures during the 3 first years after eruption did not differ from the figures for the later years. Throughout the study, caries occurrence was symmetric and no gender differences were observed. No postponement of decay was found by the end of the follow-up time.

Adolescent↗
PubMed2006

Comparative plaque removal efficacy of a dual-action power toothbrush and a manual tooth: effects by tooth type.

PURPOSE: To evaluate the plaque removal efficacy of a dual action power toothbrush (Crest SpinBrush Pro Clean) relative to an ADA reference manual toothbrush. In addition to overall plaque removal, emphasis was put on plaque reduction around the gingival margin, interproximal areas of the tooth and in the posterior segment of the dentition. METHODS: The study was a randomized, examiner-blind, two-treatment, four-period, crossover design. After an informed consent, 50 healthy volunteers were randomized to four treatment sequences and used each toothbrush twice according to their assigned treatment sequence. At every visit, plaque removal was assessed at baseline and after a single brushing using the Rustogi-modified Navy Plaque Index that allows estimation of interproximal plaque and plaque at the gingival margin. Self-reported and examiner-observed adverse events were collected at every visit. Mean Plaque Index (MPI) scores were calculated for the whole mouth, gingival region, interproximal region and different areas of the dentition using an analysis of covariance for crossover design with baseline plaque score as the covariate. RESULTS: 49 subjects provided complete data and were included in the analysis. Baseline MPI scores were not significantly different between the groups for any investigated tooth region or dentition area. Following a single brushing, the power toothbrush provided a reduction of 43% (P< 0.001) for the whole mouth MPI, 43% (P< 0.001) for the gingival margin MPI and 65% (P< 0.001) for the interproximal MPI relative to a manual brush. Use of the power toothbrush resulted in a significant reduction of whole-mouth and gingival margin MPI across all areas of the dentition compared to a manual toothbrush (P< 0.001). The power toothbrush also had superior interproximal plaque removal efficacy compared to the manual toothbrush for molars (P< 0.001, with 118% greater removal score). Both brushes were well tolerated.

Adult↗
PubMed1990

[Adhesion of restorative resin to tooth substance. Treatment of tooth surface with aqueous solution of amino-acid derivatives and HEMA].

Although many studies have been made on the reinforcement of the bond between tooth and restorative resin, satisfactory results have not been obtained clinically. Attempts were made to obtain such a reinforced bonding using the aqueous solution of derivatives of amino acid, either N-methacryloyl alanine (MAL) or N-acryloyl alanine (AAL), and 2-hydroxyethyl methacrylate (HEMA). Following the treatment with these surfactants, a tensile bond strength of 103 kgf/cm2 (to enamel) and 80 kgf/cm2 (to dentin) was obtained by MAL-HEMA solution, and that of 99 kgf/cm2 (to enamel) and 58 kgf/cm2 (to dentin) in the case of AAL-HEMA solution. This is considered as the result of either the etching effect of the amino acid derivatives, effect of its reactive products with hydroxyapaptite or reaction between HEMA and an organic component of tooth structure, like a collagen.

Acid Etching, Dental↗
PubMed1989

[The design of removable appliances for tooth movement and tooth migration].

Removable/functional appliance therapy can still be further expanded and developed. Retentive elements in the anterior region increase anchorage. Thereby, active forces can be utilised without anchorage loss. Functional appliances are indicated following extraction, to maximise on tooth migration. In first molar extraction cases, treatment with activators is relatively straightforward. When considering premolar extraction cases with possible need for extraction later of the third molars as well, then one should consider extraction of the first permanent molars. With correct use of the appliance, it is possible to optimally align the second molar teeth as well as favourably influencing the soft tissue profile.

Activator Appliances↗
PubMed2000

Single tooth-by-tooth crowns over Frialit-2 implants.

Optimizing aesthetics in the anterior maxilla can be a challenge because of tissue contouring problems. Dental implants allow for restoration of edentulous areas, thus improving function. Some compromises may result as a result of the necessity of predicting the stability of the replacement restorations. The Frialit-2 dental implant system with the internal hex design provides excellent stability for single-tooth restorations. Aesthetics are maximized using Procera Allceram crowns. This case study describes in detail the following: diagnosing and treatment planning for a challenging trauma case; surgical preparation and placement of two Frialit-2 dental implants in the maxillary left central and lateral incisor areas; primary impression techniques and fabrication of a temporary prosthesis over ProTect abutments; second-phase opening; final impressions; and fabrication of two single crowns.

Adult↗
PubMed2004

Effects of removing residual peroxide and other oxygen radicals on the shear bond strength and failure modes at resin-tooth interface after tooth bleaching.

PURPOSE: To investigate the effects of removing residual peroxide on the bond strength and the failure mode at the interface of resin-based composite and enamel after tooth bleaching. METHODS: Standard-sized light-cured resin cylinders were formed on, and bonded to the flattened bleached enamel surfaces of 60 human canine and premolars which had previously been subjected to three different surface treatments for 3 minutes: (1) catalase; (2) 70% ethanol; (3) sprayed water. For each experimental group (n=12), non-bleached teeth and 2-week post-bleached teeth without any surface treatment were used for negative and positive control respectively. Specimens were thermocycled, tested in shear until failure, and the results statistically analyzed. All fractured specimens were examined by scanning electron microscopy. RESULTS: Pretreatment of bleached surface with the catalase and the ethanol prior to bonding significantly improved the composite-enamel bond strength compared to the water-sprayed group (P< 0.05). However, the bond strength level of the ethanol group did not return to the level recorded for the non-bleached negative control group. Scanning electron microscopic examination of randomly selected, fractured specimens indicated that the peroxide-induced reduction in bond strength was related to alterations in both attachment-surface area at the resin-enamel interface and resin quality.

Analysis of Variance↗
PubMedDate not supplied

[Tooth by tooth epidemiological study of caries in 3,400 children].

The DMF index distribution and the D, M, and F distributions on the whole teeth were described from a representative sample including 3,400 children at ages 6, 9 and 12. Results showed a great symetry for dental caries on each side of the median sagittal plane. The main spots of dental attack were found and the importance of each tooth in the determination of various indexes was analyzed. At each age, the first permanent molars are the most atracked. Many children have three or four decayed molars. Concerning the eruption of permanent teeth and the loss of primary teeth, we found the same symetry of these events between upper and lower maxillar as well as from on side of the median sagittal plane to the other.

Child↗
PubMed1993

Relationships between serial blood lead levels and exfoliated tooth dentin lead levels: models of tooth lead kinetics.

Because bones and permanent teeth accumulate lead, exfoliated deciduous teeth have been utilized as retrospective markers of cumulative exposure in epidemiological surveys. In this paper we describe four models of lead uptake by the coronal dentin of shed primary teeth, each with different assumptions and ramifications. Each model is characterized by different relationships between blood lead at several ages and tooth lead. Values observed in our cohort of normal Boston children are most compatible with models positing the largest lead contribution coming at older ages (i.e., closer to age at exfoliation). Characteristics of models incompatible with our data include (1) lead deposition only during initial calcification and (2) no loss or resorption of lead.

Dentin↗
PubMed1994

Denture tooth selection: size matching of natural anterior tooth width with artificial denture teeth.

This project, conducted by the Removable Prosthodontic faculty, compared the mesiodistal widths of the six maxillary anterior teeth with the widths of denture teeth from six different denture tooth manufacturers. Four hundred eighty-eight casts of dental students were measured from the distal aspect of each canine across the facial surfaces of the six anterior teeth with a flexible plastic millimeter rule. Denture teeth from six manufacturers were compared (370 molds). The results indicated that denture teeth are predominantly smaller and natural teeth are larger.

Cuspid↗
PubMed2005

Mild early onset axonal Charcot-Marie-Tooth disease not linked to other axonal Charcot-Marie-Tooth loci.

Autosomal dominant axonal Charcot-Marie-Tooth disease type 2 (CMT2) is a heterogeneous group of disorders with seven chromosomal loci mapped in the uncomplicated forms of CMT2. The authors report clinical, electrophysiologic, and genetic analysis of a Polish CMT2 family. Nine known CMT2 gene loci and one MPZ gene locus have been excluded. The authors' findings suggest that this family represents a novel form of CMT2 disease.

Action Potentials↗
PubMedDate not supplied

Microtensile bond strength of tooth-colored materials to primary tooth dentin.

PURPOSE: This study measured the microtensile bond strengths of 2 tooth-colored restorative materials with and without conditioning of primary teeth dentin, and examined the micromorphology of the debonded surfaces and material-dentin interfaces. METHODS: Cylindrical specimens of packable composite resin (PCR) and resin-modified glass ionomer cement (RMGIC) bonded to dentin of primary teeth were ground to an hourglass shape and tested for microtensile bond strength. The debonded surfaces and material-dentin interfaces were prepared and examined under a scanning electron microscope (SEM). RESULTS: The microtensile bond strength values (mean +/- SD, in MPa) of PCR (Filtek P60 with Single Bond) and RMGIC (Fuji II LC), with or without the application of Cavity Conditioner (14.8 +/- 5.36, 12.01 +/- 4.43, 11.94 +/- 4.60, respectively), did not differ significantly (P > .05). Partial adhesive and partial cohesive failures within the restorative material predominated. The distributions of failure modes did not differ significantly between groups (P > .05). Under SEM, each material was seen to be closely adapted to dentin. Dentinal tubules were enlarged with etching, and the depth of penetration of resin tags of PCR was greater than for RMGIC. Smear plugs were incompletely removed by cavity conditioning. CONCLUSIONS: The bond strength of the PCR, Filtek P60 with Single Bond, to dentin of primary teeth was comparable to that of the RMGIC, Fuji II LC. Conditioning of the cavity preparation with Cavity Conditioner did not improve the bond strength of Fuji II LC. The distribution of failure modes did not differ between materials.

Acid Etching, Dental↗
PubMed2004

Tooth size symmetry--a comparative analysis of tooth sizes among secondary school children.

A study was carried out to determine the mesio-distal crown dimensions of permanent teeth, and to find out if there were any symmetry of the tooth sizes in a population of Nigerian children. The sample consisted of 250 secondary school children (125 males and 125 females) randomly selected from 3 secondary schools within Ibadan metropolis. Their age ranged from 12-15 years the mean age was 12 +/- 0.5 years. The results showed that there were no significant differences (p > 0.05) between the right and left sides of the dental arch with the exception of the maxillary second premolars and the female mandibular canines.

Adolescent↗