Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “TOOTH”

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 37 records · Page 2Linked to original sources

Tooth retention and tooth loss in the permanent dentition of adults: United States, 1988-1991.

While the overall prevalence of tooth loss and edentulism has been declining in the United States over the past several decades, important variations remain among subgroups of the population. Data from Phase 1 of the Third National Health and Nutrition Examination Survey (NHANES III) provide the most current estimates of the prevalence and distribution of tooth retention and tooth loss in the United States. Weighted analyses were conducted for all adults 18+ years of age (n=8,366) and for selected age, gender, and race-ethnicity groups. In 1988-91, 89.5% of the population was dentate, and 30.5% had retained all 28 teeth. The mean number of teeth retained was 21.1 for all adults and 23.5 for dentate persons. The most commonly retained teeth in the mouth were the six anterior teeth in the lower arch. Conversely, 10.5% of the population was edentulous. Partial edentulism was much more common in the upper arch than in the lower arch. The most commonly missing teeth were the first and second molars. Age was strongly related to every measure of tooth retention and tooth loss. Gender was not related to any of these measures, after adjustment for age. Race-ethnicity was consistently related to these measures, after adjustment for age and gender. In general, Mexican-Americans had the lowest and black non-Hispanics the highest rates of tooth loss. Future research needs to examine a wide range of potential correlates of tooth retention and tooth loss before we can understand the complex interplay among the personal, dental, and environmental factors influencing tooth retention and tooth loss in the United States.

Adolescent↗

Periodontal effects of rapid maxillary expansion with tooth-tissue-borne and tooth-borne expanders: a computed tomography evaluation.

INTRODUCTION: The force delivered during rapid maxillary expansion (RME) produces areas of compression on the periodontal ligament of the supporting teeth. The resulting alveolar bone resorption can lead to unwanted tooth movement in the same direction. The purpose of this study was to evaluate periodontal changes by means of computed tomography after RME with tooth-tissue-borne and tooth-borne expanders. METHODS: The sample comprised 8 girls, 11 to 14 years old, with Class I or II malocclusions with unilateral or bilateral posterior crossbites Four girls were treated with tooth-tissue-borne Haas-type expanders, and 4 were treated with tooth-borne Hyrax expanders. The appliances were activated up to the full 7-mm capacity of the expansion screw. Spiral CT scans were taken before expansion and after the 3-month retention period when the expander was removed. One-millimeter thick axial sections were exposed parallel to the palatal plane, comprising the dentoalveolar area and the base of the maxilla up to the inferior third of the nasal cavity. Multiplanar reconstruction was used to measure buccal and lingual bone plate thickness and buccal alveolar bone crest level by means of the computerized method. RESULTS AND CONCLUSIONS: RME reduced the buccal bone plate thickness of supporting teeth 0.6 to 0.9 mm and increased the lingual bone plate thickness 0.8 to 1.3 mm. The increase in lingual bone plate thickness of the maxillary posterior teeth was greater in the tooth-borne expansion group than in the tooth-tissue-borne group. RME induced bone dehiscences on the anchorage teeth's buccal aspect (7.1 +/- 4.6 mm at the first premolars and 3.8 +/- 4.4 mm at the mesiobuccal area of the first molars), especially in subjects with thinner buccal bone plates. The tooth-borne expander produced greater reduction of first premolar buccal alveolar bone crest level than did the tooth-tissue-borne expander.

Adolescent↗

[Pharmacological study of tooth formation and mineralization using a tooth germ cultivation system].

In this study, we introduce a cultivation method for mandibular first molars from mouse embryos. We also investigate the in vitro effects of several drugs on tooth formation. Histological observations demonstrated that the tooth germ dissected from 17-day-old embryonic mice and cultivated for 7 days under the conditions described here showed clear mineralization in the dentin and enamel. Alkaline phosphatase (ALP) activity and calcium content in the tooth germ increased developmentally during 7-day cultivation. The increase of calcium was preceded by that of ALP in the germ. The removal of ALP attached covalently to the external surface of plasma membranes by phosphatidylinositol specific phospholipase C disturbed in vitro mineralization in the tooth germ, suggesting that ALP functioning as an ectoenzyme is involved in the physiological process of tooth formation. To elucidate the effects of calcium regulating hormones and several drugs on tooth mineralization, ALP and calcium content were measured and also the tooth germ was observed histologically. The results obtained from the present study suggest that this in vitro system provides a useful tool for investigating both the direct action of drugs on tooth formation and the mechanisms of drug action.

Alkaline Phosphatase↗

Disturbed tooth eruption in osteopetrotic (op/op) mice: histopathogenesis of tooth malformation and odontomas.

BACKGROUND: Odontoma-like structures are formed in the jaw bone of osteopetrotic (op/op) mice, which have a congenital deficiency in osteoclastic differentiation due to the absence of functional macrophage colony-stimulating factor (M-CSF). METHODS: To clarify the histopathogenesis of tooth malformation and odontoma-like structures, a 2-year postnatal process of development of the op/op mandibular incisor was examined radiologically and histologically. At the same time, extracellular matrix (ECM) remodeling around tooth germs was analyzed immunohistochemically. RESULTS: Abnormal forms of op/op tooth germ were noticeable even at 3 days after birth on a radiogram. Histologically, op/op mice were clearly distinguished by the disappearance of dental follicular space at 3 days. With aging, bone trabeculae, which were not remodeled, penetrated into op/op tooth germs and divided them into several daughter germs, which were recognized as odontomas. In mandibular incisor bodies, the immature ECM components, such as heparan sulfate proteoglycan and tenascin, were preserved diffusely in the dental papilla/pulp, which indicates that maturation of the stroma does not take place in op/op mandibular incisors. CONCLUSION: The observation suggests that the disturbed morphogenesis of op/op tooth germs is functionally explained by the disordered immunolocalization of ECM molecules, and that the dental follicular space is essential for normal tooth development because it prevents bone penetration into the tooth germs.

Animals↗

[A study on tooth marks--morphological differences between dentitions and tooth marks thereof and selection of measurement items effective in identification].

Tooth marks in human skin assume so various aspects depending upon such factors as the forms and properties of the bitten regions that they do not necessarily represent the dentition of a suspect as it is. In the present study a cylindrical dummy with skin-like elasticity was used as a recording medium on which to make experimental tooth marks. Morphological comparisons were made of the tooth marks with the oral models by the use of measurements of 28 items. Furthermore, the selection of the effective items for identification was also considered by applying the discriminant analysis to the rate of morphological change on the base of the measurements. The results obtained were as follows: 1) In respect of the tooth marks and the oral models derived from the same subject, the values of their difference (i.e., the measured value of the former minus that of the latter) were calculated for each item so that the directional changes of the tooth marks should be investigated. It was found that the values for the lengths of the dental arch showed a tendency to be positive and that those for the widths negative, and that the values for the angles of lateral incisors and canines tended to be positive. 2) Among the mean values of the rates of morphological change for each item on the same subject, those for the lengths of the dental arch were larger, whereas those for the widths were smaller. Regarding the widths of tooth edge, large were those values for the mandibular canines in particular. 3) The identifying indices were calculated from the rate of morphological change on the basis of the measured values for 28 items in 400 combinations of the oral models with the tooth marks. They indicated that, out of the combinations derived from different subjects, 11.3% for maxillary overlapped those from the same subject and so did 8.7% for mandible in the distribution of their indices. 4) A discriminant analysis was carried out for identification. The range of coefficients thereby obtained rendered it possible to consider how much each item contributed to identification. As a result, the range of the inter-canine distance was largest. It could be considered that these items are effective in identification for tooth marks by using measurements.

Bites, Human↗

Experimental tooth movement under light orthodontic forces: rates of tooth movement and changes of the periodontium.

AIM: To investigate light forces for experimental tooth movement. METHOD: Light orthodontic forces of 1.2, 3.6, 6.5, and 10 g force (gf) were applied for 14 days to move rat molars, and the effects of the forces on the rate of tooth movement and changes of the periodontium were examined. RESULTS: In the early period, despite the different levels of force used in each group, there were no significant differences in tooth displacement. From hour 56 to day 14, the tooth displacement in the 1.2 gf group was significantly smaller than that in the other groups and the rate was nearly constant. The rates of tooth displacement in the 3.6, 6.5, and 10 gf groups fluctuated repeatedly, while the orthodontic forces gradually decreased. CONCLUSION: Experimental tooth movement in rats, tipping without friction under light forces, were either constant or fluctuated in cycles of several days' duration. This is in contradiction to the three-phases-theory of tooth movement described in previous investigations using heavy forces.

Alveolar Process↗

A six-week clinical efficacy study of a tooth whitening tartar control dentifrice for the removal of extrinsic tooth stain.

The objective of this double-blind clinical study was to investigate the tooth whitening efficacy of a new commercially available calculus-inhibiting dentifrice (Colgate Tartar Control Plus Whitening Fluoride dentifrice) containing tetra-sodium pyrophosphate, sodium tripolyphosphate, and PVM/MA copolymer in a 0.243% sodium fluoride/silica base (test dentifrice), compared to a commercially available, non-tooth whitening dentifrice containing 0.243% sodium fluoride in a silica base (control dentifrice). Following a baseline examination for, extrinsic tooth stain, qualifying adult male and female subjects from the Manchester, United Kingdom area were randomized into two treatment groups which were balanced for gender, age and level of extrinsic tooth stain. Subjects were instructed to brush their teeth twice daily (morning and evening) for one minute with their assigned dentifrice using a soft-bristled toothbrush. Examinations for extrinsic tooth stain were repeated after six weeks' use of the study dentifrices. Seventy-nine(79) subjects complied with the protocol and completed the entire study. At the six-week examination, subjects assigned to the test dentifrice treatment group exhibited statistically significant reductions of over 40% with respect to both extrinsic tooth stain area and extrinsic tooth stain intensity relative to those subjects assigned to the control dentifrice treatment group.

Adult↗

Tooth brushing, tooth wear and dentine hypersensitivity--are they associated?

Evidence suggests that patients suffer the painful symptoms of dentine hypersensitivity when dentine is exposed and the dentinal tubule system is opened to the oral cavity to allow stimuli to trigger a neural response in the pulp via a hydrodynamic mechanism. The processes needed to localise lesions of dentine hypersensitivity include loss of enamel and/or gingival recession. Whilst tooth brushing with or without toothpaste appears to cause minimal wear to enamel (in the absence of acids), circumstantial evidence implicates tooth brushing with gingival recession and exposure of dentine. Other tooth wear processes notably attrition and acid erosion cause loss of enamel and can expose dentine. Therefore sensitivity may result. How lesions of dentine hypersensitivity are initiated is a matter of conjecture and based on extrapolating data from studies, mainly in vitro, to affect in vivo. Again this circumstantial type of evidence suggests that abrasion by some toothpastes and erosion by dietary acid could open the tubule system. Little is known about the actual effect of desensitising toothpastes on lesions of dentine hypersensitivity even though they are formulated to either occlude dentinal tubules or block the neural response in the pulp. Clinical studies have produced contradictory findings for the efficacy of products and there have been extremely few evidence based reviews. In conclusion, available evidence supports a probable link of tooth brushing, with or without toothpaste and an acidic diet to both tooth wear and dentine hypersensitivity, and suggests also that dentine hypersensitivity is a tooth wear phenomenon. Although there is a need for more direct clinical and scientific evidence for these associations, it is recommended that they be taken into consideration when planning management strategies for the dentine hypersensitivity sufferer.

Dental Enamel↗

[Experimental study of bone resorption after tooth extraction with implanted hydroxyapatite tooth root substitute].

Hydroxyapatite (HAP) tooth root substitute implantation have been applied to extraction sockets in many studies for purpose of preservating alveolar bone. Dimensional changes were measured with sectioned study cast of cephalometric X-ray photo. In this study, dimensional changes were determined by newly developed evaluation system which utilizing image analyzer (Immunomedica Co., Ltd.), in a view of conserving alveolar ridges beneath the denture base. Cone shaped HAP tooth roots (5 or 6 mm in length) were implanted to one subject and disk-like shaped HAP tooth roots (2 mm in length) were also implanted to the other subject. Preservation of alveolar bone was observed in both shaped HAP tooth roots implanted site compared to control site. Bony ankylosis between HAP tooth root and alveolar bone, observed on 1 month after histological specimens, may contribute to this result. Smaller changes of blood flow compared to controls were obtained on implanted site, which were measured with Laser Doppler blood flow meter (Perimed KB; Sweden) on buccal mucosa. We consider that HAP shows good biocompatibility and HAP tooth roots implantation decrease the wound volume consequently.

Alveolar Bone Loss↗

Use of a synthetic bone substitute to retard molariform tooth drift after maxillary tooth loss in ponies.

OBJECTIVE: To evaluate the effect of alveolar bone substitute on post-extraction drift of maxillary cheek teeth in ponies. STUDY DESIGN: In vivo longitudinal experimental study. ANIMALS: Five ponies (5-7 years) with a healthy dentition. METHODS: Both maxillary 4th premolar teeth (Triadan 08) were surgically removed. One alveolus was filled with a biocompatible non-resorbable bone substitute (Bioplant 24), whereas the other healed by second intention. A polyvinylsiloxane plug and spring wire isolated the bone substitute from the oral environment. Pathologic changes to dentition and adjacent soft tissue were recorded. Tooth drift was calculated after 1 and 2 years. RESULTS: At 1 month, bone substitute material was incorporated into healthy tissue. Tooth drift was observed but differed significantly between control and treated sides at 2 years (P<.01). For both techniques, tooth drift differed significantly between years 1 and 2 (P<.001). Total drift in control arcades for year 1 was 10.69+/-2.12 mm and for year 2 was 9.08+/-0.87 mm, whereas for bone substitute arcades it was 9.90+/-1.60 mm for year 1 and 5.60+/-1.78 mm for year 2. CONCLUSIONS: Partial tooth replacement therapy after maxillary P4 extraction provided good healing in the immediate post-surgical phase. Alveolar filling with bone substitute material significantly slowed post-extraction tooth drift but did not stop it completely. Clinical Relevance- Important changes occur in equine dentition after maxillary cheek teeth removal. Further longer term observations are needed to fully validate study findings.

Animals↗

Parathyroid hormone-related peptide is involved in protection against invasion of tooth germs by bone via promoting the differentiation of osteoclasts during tooth development.

In order to elucidate the role of parathyroid hormone-related peptide (PTHrP) in tooth development, we treated tooth germ explants of mouse molars with antisense phosphorothioate-oligodeoxynucleotide (ODN) against PTHrP. Antisense ODN-treatment of the explants resulted in the invasion of the tooth germs by bone. The number of tartrate-resistant acid phosphatase (TRAP)-positive cells around the tooth germs in antisense ODN-treated explants was much lower than that of the control explants. Electron microscopic examination suggested that the antisense ODN-treatment inhibited differentiation of osteoclasts. Treatment of the explants with bisphosphonate or vitamin K2, inhibitors of the differentiation of osteoclasts, induced the invasion by bone into the tooth germs as observed in the antisense ODN-treated explants. The results obtained suggest that PTHrP is involved in the mechanism protecting tooth germs from bone invasion by promoting the differentiation of osteoclasts around them.

Animals↗

Assessment of tooth mobility using small loads. I. Technical devices and calculations of tooth mobility in periodontal health and disease.

An apparatus for recording tooth mobility of maxillary anterior teeth using loads below 100 p in a bucco-lingual direction is described. Strain gauges and a differential transformer are used as sensors of force and displacement. The displacement is recorded at the same location on the tooth surface and in the same direction as the loading force. Compressed air is used as the source of force. Documentation of signals is obtained by means of a two-channel potentiometric recorder. Tooth mobility was studied in six subjects with healthy periodontal conditions and in six subjects with moderate periodontal disease. Repeated measurements under standardized conditions demonstrated a satisfactory reproducibility of the measuring method. Tooth mobility curves within the 20-80 p loading range were transformed to lines of regression. Analysis of such lines seems to provide further information of tooth mobility qualities as compared to previous methods of tooth mobility measurements.

Dental Stress Analysis↗

The single-tooth implant: a viable alternative for single-tooth replacement.

BACKGROUND: The use of dental implants for single-tooth replacement cases introduces a challenge to the performance of these restorations. Clinical data suggest that single-tooth implant restorations do not benefit from lateral support from the surrounding dentition as do bridged implants, and that these restorations are subjected to greater masticatory forces. Therefore, single-tooth implants are exposed to an increased risk of failure. This prospective clinical trial was designed to evaluate the cumulative success rate of dual acid-etched single-tooth replacement implants in two clinical centers. METHODS: The study protocol included 59 patients between 19 and 73 years. Implants were evaluated for mobility, infection, and crestal bone loss from 30.9 to 60 months. RESULTS: Seventy-one (71) implants were placed in 59 patients, 20 male and 39 female. Forty-seven (47) were placed in the maxilla and 24 in the mandible. The percentages of anterior and posterior implants were 45.1% and 54.9%, respectively. A total of 13 (18.4%) implants were placed in soft, poor quality (Type IV) bone. Beginning 1 month post-implant placement, cases were followed for 30.9 to 60 months with a mean follow-up of 45.9 months. One implant failed (peri-implant infection) yielding an overall success rate of 98.6%. CONCLUSIONS: This success rate for single-tooth replacement dual acid-etched implants compares favorably with bridged implants and with success rates of other single-tooth implant studies. Dual acid-etched implants performed well even under conditions of poor quality bone, where concomitant bone augmentation was performed, and when used for immediate replacement of extracted teeth.

Acid Etching, Dental↗

[Restoring ceramo-metal tooth by using self-made crown post-core in order to re-utilize the broken crown of the base tooth].

OBJECTIVE: To explore a new method and its clinical significance of restorative ceramo-metal by using a self-made crown post-core to reutilize the broken crown. METHODS: 18 teeth were restored with ceramo-metal tooth by using self-made crown post-core in order to preserve the old broken base tooth. The patients' own feelings and clinical effect were observed. RESULTS: Followed up for 1-3 years, 83.3% (15 teeth) of the patients were successful. Among the group one was failed because of bad condition of post and caused split of tooth root. The second failure was caused by uneven force by coherent paste uneven. The third failure was caused by tight biting force and caused the tooth broken. CONCLUSION: Restoring ceramo-metal tooth by using self-made crown post-core in order to re-utilize the broken crown of the base tooth is convenient and low cost and is suitable for basic hospitals.

Crowns↗

[Scanning electromicroscopic studies of the surface of teeth. I. After manual treatment with tooth cleansers. II. Tooth cleaning with power-driven instruments].

Scanning electron microscopic examination of tooth surfaces after using manually operated instruments to remove calculus showed distinct lesions on the hard substances of the tooth. The extent of damage depends considerably on the area of the tooth treated (the border between the enamel and the cementum is particularly endangered), the amount of force used, and the length of time required for treatment. Examination of tooth surfaces following application of various types of power-driven scaling instruments revealed that lesions of the hard substances on the tooth are possible. The extent of the damage depends on several different factors, particularly the pressure applied and the area of the tooth treated. The border between the enamel and the cementum is particulary endangered.

Dental Cementum↗

Reasons for tooth extractions in dental practices in Ontario, Canada according to tooth type.

In a study of tooth extractions in general dental practices in Ontario, Canada, 165 dental practitioners provided information on 6134 patients attending during a reference week. Of these, 11.6 per cent of patients had one or more permanent teeth extracted. Periodontal disease was given as the reason for 35.9 per cent of these extractions and caries for 28.9 per cent. Analysis by tooth type showed that third molars were the most common tooth type extracted. However, there were differences in the types of teeth extracted by age. Posterior teeth were most frequently lost by the younger age groups and anterior teeth by older subjects. There were also differences in the reasons for the loss of different tooth types. A comparison of these results with those of a similar study in Scotland suggests that age and tooth type does not account for the excess of extractions due to periodontal disease in this Canadian population. Differences in practice patterns and attitudes towards the retention of teeth may be contributing factors.

Adolescent↗

Micro-CT evaluation of tooth, calvaria and mechanical stress-induced tooth movement in adult Runx2/Cbfa1 heterozygous knock-out mice.

Runx2/Cbfa1 is essential for osteoblast differentiation and bone formation. Runx2 null mice (Runx2(-/-)) completely lack mineralized tissue and die soon after birth, whereas Runx2 heterozygous knock-out mice (Runx2(+/-)) stay alive but show morphological defects in the skeletal system as observed in cleidocranial dysplasia (CCD) in humans. The aim of this study is to elucidate the role of Runx2 in adult mineralized tissue and also to reveal the distinct features of heterozygous deletion of Runx2 in response to tooth movement. Therefore, we examined the cranium, tooth and the periodontium in adult Runx2(+/-) using soft X-ray and micro-CT. In addition, tooth movement induced by mechanical loading was evaluated. In adult Runx2(+/-), crown:root ratio of the first maxillary molar was significantly lower than that of wild type (WT). Irregularities in root morphology was also observed. The cranium was narrow with thin parietal bone compared to WT. Mechanical stress-induced tooth movement was similar between Runx2(+/-) and WT in terms of movement distance. However, while rotational movement between the first and third week was increased in WT, it was not altered in Runx2(+/-) mice. These data indicate that Runx2 plays a role in cranium and the tooth development in adulthood.

Animals↗