Abstract:
:The temporal and spatial patterns in which teeth are initiated in the growing jaws of embryos are constant for a species but different for different species. The sources of the patterns have been explained in two ways. First, they are the outcome of reactions between molecules created at stationary targets and those which diffuse through embryonic tissues (e.g., Edmund, 1960). Second, Osborn (1978) supposed that the patterns mirror the way a (mixed) population of parent cells, the tooth clone, grows. Westergaard and Ferguson (1986, 1987, 1990) concluded, from their observations of the sequence of tooth initiation in alligators, that the complicated sequences in which 20 teeth are initiated in each tooth quadrant could not be explained by jaw growth. The present study attempts to refute this criticism by means of measurements made from the raw data published by Westergaard and Ferguson. These data reveal that new teeth, here called primary teeth, are added at a constant rate at the back of the jaw. Interstitial growth of the cells between primary teeth creates space for secondary teeth in secondary regions. The secondary regions increase in length exponentially with time. The sequence in which teeth are initiated in the growing secondary regions was found to be the same in every part of the upper and lower jaws. It was accurately reproduced by a computer program based on a linear contraction rate of inhibitory zones and exponential growth of secondary regions. The results suggest that the posterior progress zone in alligator embryos grows about 125 microm a day. Newly initiated tooth germs are surrounded by an inhibitory zone about 250 microm in diameter. These zones contract from 20 to 30 microm a day until they are about 170 microm in diameter. The sequences in which tooth positions are initiated in embryos may be more the result of the pattern in which cells escape from molecules that inhibit induction rather than the pattern in which cells create molecules that initiate induction.
journal_name
J Dent Resjournal_title
Journal of dental researchauthors
Osborn JWdoi
10.1177/00220345980770090901subject
Has Abstractpub_date
1998-09-01 00:00:00pages
1730-8issue
9eissn
0022-0345issn
1544-0591journal_volume
77pub_type
杂志文章abstract::Previous studies have clearly established the down-regulating effect of a sucrose-rich diet on primary dentinogenesis in rat molars. Earlier observation of the negative effect of a high-sucrose diet on a parotid function involved in the control of intradentinal solute movement led us to hypothesize that parotid gland ...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/154405910208100407
更新日期:2002-04-01 00:00:00
abstract::The feasibility of immunizing monkeys with enzymes from oral streptococci in an attempt to reduce dental caries was investigated. Forty rhesus monkeys, Macaca mulatta, were used. Cariogenic streptococci, S mutans, were implanted into all the monkeys' mouths. There was no pathological effect resulting from immunization...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345770560123001
更新日期:1977-12-01 00:00:00
abstract::Amylase activity in various tissues--i.e., submandibular/sublingual and parotid glands, the pancreas, saliva, and serum--in rats was measured after injection of isoproterenol, pilocarpine, and acetylcholine. All agents reduced amylase activity in the parotid gland and increased the enzyme activity in the submandibular...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345830620011201
更新日期:1983-01-01 00:00:00
abstract::Dentinal pain in connection with mechanical stimulation i.e. probing, chiseling and initial drilling may be due to removal of fluid from the dentinal tubules. Loss of fluid due to "normal" evaporation from exposed dentin may produce an outward flow in the dentinal tubules rapid enough to cause pain and within a few mi...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345780570012001
更新日期:1978-01-01 00:00:00
abstract::The clearance of glucose from saliva was compared with that from spaces located in an intra-oral appliance. The spaces (N = 8) were similar in shape and size to posterior interdental spaces and could be sampled with a microsyringe without removing the appliance from the mouth. The subjects (N = 5) rinsed their mouths ...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345850640030301
更新日期:1985-03-01 00:00:00
abstract::Periodontal diseases are initiated by bacteria that accumulate in a biofilm on the tooth surface and affect the adjacent periodontal tissue. Systemic diseases such as diabetes, rheumatoid arthritis (RA), and systemic lupus erythematosus (SLE) increase susceptibility to destructive periodontal diseases. In human studie...
journal_title:Journal of dental research
pub_type: 杂志文章,评审
doi:10.1177/0022034518805739
更新日期:2019-02-01 00:00:00
abstract::Phosphatases are involved in bone and tooth mineralization, but their mechanisms of action are not completely understood. Tissue-nonspecific alkaline phosphatase (TNAP, ALPL) regulates inhibitory extracellular pyrophosphate through its pyrophosphatase activity to control mineral propagation in the matrix; mice without...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/0022034513490958
更新日期:2013-08-01 00:00:00
abstract::In two separate experiments, none of the 14 subunits examined consistently ranked dentifrices similarly to the ranking obtained when the individual rat was used as the experimental unit. Arbitrarily dividing the rat into subunits and then comparing results among these subunits may lead to false conclusions since the r...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345760550032901
更新日期:1976-05-01 00:00:00
abstract::Heads of Swiss-Webster mouse fetuses of four ages spanning days 12-13 of gestation, were partially dissected by removing the brain (B), tongue (T) and mandible (M) alone or in combination (BT, BM, BTM). Preparations were suspended in a gassed, circulating culture system such that palatal closure must take place agains...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345780570024401
更新日期:1978-02-01 00:00:00
abstract::The anticaries effect of professional fluoride (F) application has been attributed to calcium-fluoride-like deposits (CaF(2)) formed on enamel, but this has not been clearly demonstrated. We hypothesized that CaF(2) formed on plaque-free enamel by F application would reduce enamel demineralization due to the increase ...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/154405910808701105
更新日期:2008-11-01 00:00:00
abstract::During periods of periodontal attachment loss, one of the most significant cellular changes is a decrease in the number of fibroblasts. We previously demonstrated that LPS induces apoptosis of fibroblastic cells in vivo, largely through TNF-alpha. We conducted in vivo experiments by subcutaneous inoculation of LPS in ...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/154405910408300903
更新日期:2004-09-01 00:00:00
abstract::The object of the present study was an attempt to relate fluoride concentration in enamel, caries experience, and the degree of fluorosis in a community residing in an area with a high level of fluoride. A significant difference was found between the male and female samples for the F and D parameters. A positive corre...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345760550012001
更新日期:1976-01-01 00:00:00
abstract::Acidic proline-rich proteins were localized histologically by means of the indirect immunoperoxidase technique in the acinar cells of parotid and submandibular gland sections of both man and Macaca fascicularis. These proteins were also identified as constituents of the long term in vivo-formed acquired pellicle on hu...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345800590081201
更新日期:1980-08-01 00:00:00
abstract::Mark Twain provides a humorous and insightful look into the origins of periodontal therapy and anesthesia in "Happy Memories of the Dental Chair". The main character of this story is Dr. John Riggs, the father of periodontics. Dr. Horace Wells, a pioneer in the field of anesthesia, also appears in the story. Twain pre...
journal_title:Journal of dental research
pub_type: 传,历史文章,杂志文章
doi:10.1177/0022034510366677
更新日期:2010-07-01 00:00:00
abstract::Synovitis in internal derangement of the temporomandibular joint (TMJ) is accompanied by the growth of new blood vessels. Fibroblast growth factor-2 (FGF-2) and vascular endothelial growth factor (VEGF) are well-characterized angiogenic factors. The objective of this study was to elucidate the correlation between the ...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/154405910308200406
更新日期:2003-04-01 00:00:00
abstract::The sequelae of sustained, in vivo delivery of two important neurotransmitter substances, glutamate and thyrotropin-releasing hormone (TRH), upon craniofacial growth and development have previously not been investigated. Our purpose was to document and compare the relative effects of glutamate and TRH microspheres ste...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345970760080601
更新日期:1997-08-01 00:00:00
abstract::Human saliva contains a number of phosphorylated acidic proline-rich proteins (APRP). Monkey parotid saliva contains a similar protein with the same phosphorylated sequences as the human proteins. A crude protein kinase was prepared from Macaca fascicularis parotid glands which phosphorylated human APRP. The enzyme wa...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345860650030601
更新日期:1986-03-01 00:00:00
abstract::It has not been established whether transmission of mutans streptococci occurs between unrelated children older than 4 years of age. The aim of the study was to investigate the possible transmission of mutans streptococci genotypes from child to child in kindergarten. We studied 96 children (ages 5-6 yrs) in three San...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/0022034509353400
更新日期:2010-01-01 00:00:00
abstract::Growing interest in the treatment and prevention of Molar/Incisor Hypomineralization (MIH) warrants investigation into the protein composition of hypomineralized enamel. Hypothesizing abnormality akin to amelogenesis imperfecta, we profiled proteins in hypomineralized enamel from human permanent first molars using a b...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/0022034510375824
更新日期:2010-10-01 00:00:00
abstract::Schoolchildren residing in a fluoride-deficient area were provided either a sodium fluoride (0.1% F) or a nonfluoride dentifrice for home use. About half the children provided each type of dentifrice were also given an initial prophylaxis. Combining the data with regard to the type of dentifrice indicated that the sod...
journal_title:Journal of dental research
pub_type: 临床试验,杂志文章
doi:10.1177/00220345750540013601
更新日期:1975-01-01 00:00:00
abstract::In a standard periodontal treatment strategy with consecutive root planings (per quadrant at a one- to two-week interval), re-infection of a disinfected area might occur before completion of the treatment. This study examines, both clinically and microbiologically, whether a full-mouth disinfection within 24 hours sig...
journal_title:Journal of dental research
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1177/00220345950740080501
更新日期:1995-08-01 00:00:00
abstract::An acidified gel system was used to produce artificial caries lesions in root surfaces. Radiopaque surface layers were found with 47% of the lesions. Demineralized bodies of the lesion and mineralized zones of banding were seen in all lesions when examined by microradiography. Cementum and dentin seemed to respond to ...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345850640050401
更新日期:1985-05-01 00:00:00
abstract::Three single-composition, high-copper amalgams were analyzed for the composition of their before- and after-reaction phases. The method used was electron probe microanalysis. The results may be summarized as follows: All alloys consist essentially of Ag3Sn (gamma), Cu3Sn (epsilon), and, in some cases, Ag4Sn (beta). Wh...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345840630062301
更新日期:1984-06-01 00:00:00
abstract::Fibroblast growth factor receptor 2 (FGFR2) in craniofacial bones mediates osteoprogenitor proliferation, differentiation, and apoptosis. The distortion of proper craniofacial bone growth may cause class II and class III skeletal malocclusion and result in compromised function and aesthetics. Here, we investigated the...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/0022034519872951
更新日期:2019-11-01 00:00:00
abstract::The effect of toothbrushes on soft tissue abrasion was measured using hamster cheek pouch tissue brushed mechanically for various intervals. The detection of protein removed during brushing was used as an index of tissue abrasion. The method was found to be sensitive in detecting the effects of brush load, number of s...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345770560070301
更新日期:1977-07-01 00:00:00
abstract::Transglutaminase-2 (TGM-2) stabilizes extracellular matrix (ECM) proteins by cross-linking and has been implicated in several fibrotic disorders. Arecoline present in betel quid has been proposed as one of the causative factors for oral submucous fibrosis (OSMF). Hence, we hypothesize that arecoline may regulate TGM-2...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/0022034508329633
更新日期:2009-02-01 00:00:00
abstract::Tempering of dental porcelain by forced convective cooling in air has been shown previously to inhibit the sizes of cracks induced in porcelain surfaces. However, the depth of compressive stress that is produced by tempering of feldspathic porcelain has not been determined. It can be assumed that the potential of temp...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345910700020701
更新日期:1991-02-01 00:00:00
abstract::Pain and discomfort are common problems for patients undergoing orthodontic treatment. We have demonstrated that cortical excitation propagation in the somatosensory and insular cortices (IC) induced by electrical stimulation of the periodontal ligament (PDL) is facilitated 1 d after experimental tooth movement (ETM)....
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/0022034520962465
更新日期:2020-10-08 00:00:00
abstract::Twenty-two adults, considered to have high caries activity, rinsed for one yr with either SnF2 or acidulated NaF mouthrinses. Total colony-forming units and numbers of S. mutans and lactobacilli were estimated from saliva samples. Large reductions were found in the number of recoverable S. mutans in subjects rinsing w...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345830620081201
更新日期:1983-08-01 00:00:00
abstract::The presence and kinetics of bone-resorbing activity in periapical lesions were studied with a rat model system. Lesions were found to expand most rapidly between induction on day 0 and day 15 ("active phase"), with enlargement occurring at a slower rate thereafter (days 20 and 30, "chronic phase"), as assessed by mea...
journal_title:Journal of dental research
pub_type: 杂志文章
doi:10.1177/00220345910700100901
更新日期:1991-10-01 00:00:00