Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “MOLAR”

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 739 records · Page 41Linked to original sources
PubMed1998

Mandibular first and second molar. The variability of roots and root canal system.

The root and canal anatomy of mandibular first and second molars has normally recurring features, as well as a great number of atypias. Normally mandibular first and second molars have two roots, one is mesial and the other is distal, and at least three main canals. The roots of the second molar can change from one to three, the first molar can have also four roots; the canals can change from three to even six. The conventional root canal anatomy indicates the location of the initial access. The knowledge of both the normal and abnormal anatomy of molars shows the parameters under which root canal therapy is to be executed and can directly modify the probability of success. This is the reason why endodontists must be familiar with all abnormalities as well as their percentage. We present a review of the modern literature about the event of aberrances with references to the number and morphology in mandibular first and second molar root and root canals.

Dental Pulp Cavity↗
PubMed1998

Development of third molars in children in Istria.

The aim of this study was to determine the prevalence of third molars in children in Istria aged 7 to 18. The study was performed on 2350 panoramic radiographs of children in Istria that have been analysed and then divided into 7 age groups. Each of these groups consisted of the same number of boys and girls. It has been found that the development of third molars starts earlier in the mandible, and that before the age of 12 there are more third molars in the mandible than in the maxilla (p < 0.01). Nine-year old girls have statistically significantly more third molars than the boys of that age, but twelve year old boys have more than the girls. The differences in the prevalence of third molars between the jaw sides was statistically significant only for mandibles of twelve year old girls. Hypodontia of third molars has been found in 4.5% of boys and 5.8% of girls aged 14 to 18.

Adolescent↗
PubMed1986

Immunobiology of complete molar pregnancy and gestational trophoblastic tumor.

The unique curability of gestational trophoblastic tumors may in part be attributable to a host immunologic response. The occurrence of rapidly progressive and fatal choriocarcinoma may be favored by histocompatibility between patients and their partners. However, histocompatibility is not a prerequisite for the development and persistence of gestational choriocarcinoma. The expression of HLA by choriocarcinoma cells in culture is enhanced following incubation with gamma-interferon and this may be of both biologic and clinical significance. Complete molar pregnancy is a complete allograft because all molar chromosomes are of paternal origin. Patients with complete mole are sensitized to paternal HLA antigen which is expressed in molar tissue. Other polymorphic antigen systems including trophoblast-leukocyte common antigens and placental-type alkaline phosphatase are also expressed in molar tissue. We have studied the immunopathology of the molar implantation site to investigate possible humoral and cellular immune responses. The relationships among normal placenta, complete mole and choriocarcinoma are not clearly understood. The pattern of expression of oncofetal antigens in these three gestational tissues may be used to assess trophoblastic differentiation. In studies to date, molar trophoblast has the same pattern of expression of oncofetal antigens as normal placental trophoblast. We will review recent advances in our understanding of the immunobiology of gestational trophoblastic disease and suggest new directions for further research.

Alkaline Phosphatase↗
PubMed2002

Poly(ethylene glycol)-mediated molar mass control of short-chain- and medium-chain-length poly(hydroxyalkanoates) from Pseudomonas oleovorans.

Three strains of Pseudomonas oleovorans, a well known poly(hydroxyalkanoate) (PHA) producer, were tested for the ability to control PHA molar mass and end group structure by addition of poly(ethylene glycol) (PEG) to the fermentation medium. Each strain of P. oleovorans - NRRL B-14682 (B-14682), NRRL B-14683 (B-14683), and NRRL B-778 (B-778) - synthesized a different type of PHA from oleic acid when cultured under identical growth conditions. Strain B-14682 produced poly(3-hydroxybutyrate) (PHB), while B-14683 synthesized a medium-chain-length PHA ( mcl-PHA) with a repeat unit composition ranging from C4 to C14 and some mono-unsaturation in the C14 alkyl side chains. Strain B-778 synthesized a mixture of PHB (95 mol%) and mcl-PHA (5 mol%). The addition of 0.5% (v/v) PEG (M(n) =200 g/mol, PEG-200) to the fermentation broth of strains B-14682 and B-778 resulted in chain termination through esterification at the carboxyl terminus of the PHB with PEG chain segments, thus reducing the molar mass by 54% and 23%, respectively. The molar mass of the mcl-PHA produced by strains B-14683 and B-778 also showed a 34% and 47% reduction in the presence of PEG-200, respectively, but no evidence of esterification was present. PEG-400 (M(n) =400 g/mol) had a reduced effect on PHA molar mass. In fact, the molar masses of the mcl-PHA derived from strain B-14683 and both the PHB and mcl-PHA from B-778 were unchanged by PEG-400. In contrast, the PHB produced by B-14682 showed a 35% reduction in molar mass in the presence of PEG-400.

Alkanes↗
PubMed1995

Case-control study of risk factors for partial molar pregnancy.

OBJECTIVE: The purpose of our study was to identify risk factors for partial molar pregnancy from a woman's general, reproductive, and dietary history. STUDY DESIGN: Sixty-five women with pathologically confirmed partial molar pregnancy were interviewed, and their experiences were compared with those of 130 age-matched control women who had successfully completed a pregnancy with delivery of a live infant at the same hospital during the same calendar period. RESULTS: Multivariate analysis revealed that exposures which independently and significantly predicted increased risk for partial molar pregnancy included irregular cycles, pregnancy histories including only male infants among prior live births, and oral contraceptive use for > 4 years. Dietary factors previously postulated for complete molar pregnancy including protein, fat, vitamin A, or carotene were found not to be related to risk for partial molar pregnancy. CONCLUSION: Epidemiologic patterns for complete and partial molar pregnancies appear to differ somewhat; risk for partial mole is associated with reproductive history but not dietary factors.

Adult↗
PubMed1990

Preparation and purification of soybean lipoxygenase-derived unsaturated hydroperoxy and hydroxy fatty acids and determination of molar absorptivities of hydroxy fatty acids.

A method was developed for the preparation and purification of polyunsaturated hydroperoxy and hydroxy fatty acids from 18:2n-6, 18:3n-6, 18:3n-3, 20:3n-6, 20:3n-3, and 20:4n-6 with soybean lipoxygenase. This method involved incubation of unsaturated fatty acids in Tris-HCl buffer with soybean lipoxygenase and extraction of reaction products on C18 solid-phase columns. The yields of conversion of fatty acid substrate to oxygenated products were in all cases greater than or equal to 95%. C18 solid-phase extracted reaction products were purified by C18 HPLC, yielding 3-4 mg of products with purities of greater than or equal to 98%. Purified polyunsaturated hydroxy fatty acids were characterized by HPLC and mass spectral analysis and showed absorption spectra with maximum absorption occurring between 234.5 and 237.5 nm due to the presence of a conjugated diene function. Polyunsaturated hydroxy fatty acid potassium salts were converted to (4-bromobenzoyl)methyl esters by reaction with 2,4'-dibromoacetophenone in the presence of 18-crown-6. Molar absorptivities for the conjugated diene functions were determined by relating their absorbance to the absorbance contributed by the 4-bromobenzoyl chromophore and its molar absorption intensity of 17.6 X 10(3) (M.cm)-1. The molar absorptivities determined for 13-OH-9,11-18:2, 13-OH-6,9,11-18:3, 13-OH-9,11,15-18:3, 15-OH-11,13-20:2, 15-OH-8,11,13-20:3, 15-OH-11,13,17-20:3, and 15-OH-5,8,11,13-20:4 ranged from 23.2 x 10(3) to 24.6 x 10(3) (M.cm)-1. The molar absorbtivity values of 18.8 x 10(3) and 20.3 x 10(3) (M.cm)-1 determined for commercial, chemically synthesized 12-OH-5,8,10,14-20:4 [12-(S)-hydroxyeicosa-5,8,10,14-tetraenoic acid (12(S)-HETE)] and 5-OH-6,8,11,14-20:4 ((+/-)-5-HETE) were lower than that of soybean lipoxygenase-derived 15-OH-5,8,11,13-20:4 (15-HETE), which exhibited a molar absorptivity of 23.3 x 10(3) (M.cm)-1. The molar absorptivity values determined for 5-, 12-, and 15-HETE are considerably lower than 30.5 x 10(3) (M.cm)-1, which was reported previously.

12-Hydroxy-5,8,10,14-eicosatetraenoic Acid↗
PubMed1983

Interaction of alpha-lactalbumin with dimyristoylphosphatidylcholine vesicles. III. Influence of the temperature and of the lipid-to-protein molar ratio on the complex formation.

We investigated the interaction between alpha-lactalbumin and sonicated dimyristoylphosphatidylcholine at pH 4 and different temperatures. (1) At 23 degrees C and lipid-to-protein molar ratios below 170, the interaction results in a disruption of the original vesicles to form smaller complex particles. By the sedimentation velocity method we determined for this particle a molar mass of (1.05 +/- 0.16) X 10(6) g X mol-1. The lipid-to-protein molar ratio within the complex particle is 70/1, as earlier estimated. It follows that there are approximately 1200 lipid and 17 alpha-lactalbumin molecules per particle. At molar ratios above 170, alpha-lactalbumin strongly associates with the vesicles. In this case the vesicle entity remains. The ability of alpha-lactalbumin to break up the vesicles at this temperature is determined by the number of protein molecules which are required in the complex particle. (2) By means of fluorescence polarization of the lipophilic probe 1,6-diphenyl-1,3,5-hexatriene and energy transfer of the tryptophan groups of the protein to 1,3-(1,1'-dipyrenyl)propane located in the hydrocarbon region of the vesicles, it is shown that with increasing temperature above 25 degrees C, complexes of decreasing internal lipid-to-protein molar ratio are formed. However, by electron microscopy we show that the overall size of these complexes remains approximately the same, i.e., bars with dimensions 70 X 220 A. A temperature-reversible transformation occurs between these complexes, which cannot be isolated by gel chromatography. In contrast, the complex of molar ratio 70/1 remains stable at lower temperatures.

Animals↗
PubMed1992

Refractive index and molar refraction of methacrylate monomers and polymers.

The refractive indices of a number of methacrylate monomers have been measured and corresponding molar refraction data calculated. Similar determinations were made on a number of methacrylate polymers. The molar refraction values determined were in excellent agreement with the values calculated from the published molar refraction values of the chemical groups involved. There was little difference between the molar refraction values of monomers and that of the repeat unit in the corresponding polymers, in marked contrast to the molar volumes. The ratio of refractive index to molar volume was reasonably consistent for all methacrylates studied (0.25-0.30 approximately).

Chemical Phenomena↗
PubMed1995

Placental isoferritin levels during first trimester of normal and complete molar gestations.

Serum placental isoferritin levels (PLF) levels were measured in 33 patients admitted for routine scanning of a first trimester normal singleton pregnancy and six patients who were hospitalized for uterine evacuation of a complete molar gestation. Venous blood was obtained upon admission and before curettage, when necessary. Serum was separated into glass tubes, immediately frozen and stored at -20 degrees C until analysed. The mean serum PLF levels were 18.1 (+/- 14) U/ml and 5.5 (+/- 2) U/ml for normal and molar gestations, respectively, with a significant difference between the two groups (P = 0.001). Sixty-seven per cent of normal pregnancies had serum PLF levels > or = 10 U/ml, whereas none of the molar gestation group reached this threshold level. Furthermore, the molar gestation group's low serum PLF levels remained unchanged throughout the entire follow-up period and until their beta-human chorionic gonadotrophin levels were undetectable. Unlike normal pregnancies, the molar trophoblast does not seem to secrete or synthesize PLF, suggesting that the complete molar placenta has different protein-producing capabilities when compared with those found in normal pregnancies. Further studies, including serum PLF among other categories of gestational trophoblastic neoplasms, are recommended before this data can be integrated into routine clinical work.

Biomarkers↗
PubMed1982

Molar proportions and relative rates of synthesis of histones in rat testis.

The molar proportions and relative rates of synthesis of histones in normal and hypophysectomized rat testis seminiferous epithelial cells were determined. After hypophysectomy the molar proportions of histones H1, H2B and (H2A + protein A24) in seminiferous epithelial cells of rat testis increased while their corresponding variants TH1-x, TH2B-x and X2 decreased, but the molar proportions of major-class histones (i.e., sum of subfractions) remained relatively constant and similar to the proportions in somatic cells. The apparent molar proportions of the labeled histones, determined immediately after 2-h periods of [3H]leucine incorporation, were much higher relative to H4 than the proportions of total histones determined by dye binding. The values, however, approached the molar proportions of total histones when rats were killed 11 days after the [3H]leucine injection. Two-dimensional gel electrophoresis confirmed that the high initial molar proportions relative to H4 by [3H]leucine incorporation were not due to the possible contamination by highly-labeled non-histone proteins. The specific activity of histone H4 relative to the specific activity of DNA, determined immediately after 3-h periods of [3H]leucine and [14C]thymidine incorporations was similar to the value when rats were killed 13 days after the injections. It is proposed that histones of seminiferous epithelial cells are synthesized disproportionally relative to H4 and in excess of the quantities required for polynucleosome assembly. The excess histones are subsequently displaced or degraded slowly.

Animals↗
PubMed1992

Pulpal effects of argon: fluoride excimer laser irradiation and acid-etching of rat molar enamel.

The reaction of enamel, dentine and pulpal tissues to exposure from a laser beam has been shown to depend on the type of laser medium used. The objective of this study was to examine the pulpal response in rat molars after external enamel surface treatment with either an Ar:F excimer laser or acid-gel application. Maxillary right molar occlusal surfaces in 22 animals were irradiated (energy density = 45.0 J/cm2). Maxillary left molar occlusal surfaces were treated with 37 per cent phosphoric acid for 30 s. Untreated mandibular right molars served as controls. At two postoperative time periods (1 and 6 weeks), molars were removed, sectioned, stained (H&E) and scored. Data analysis indicated no significant difference between Ar:F irradiation and controls at 1 week. Treatment with laser or acid-etching left a similar degree of pathosis at 1 and 6 weeks. Although the Ar:F excimer laser produced a more exaggerated pulp response than controls at 6 weeks, tissue vitality was maintained. The Ar:F excimer laser may be useful for ablating vital tooth structure since pulpal tissue in rat molars exhibited no damage in response to low-power irradiation.

Acid Etching, Dental↗
PubMed2004

Molar and molecular views of choice.

The molar and molecular views of behavior are not different theories or levels of analysis; they are different paradigms. The molecular paradigm views behavior as composed of discrete units (responses) occurring at moments in time and strung together in chains to make up complex performances. The discrete pieces are held together as a result of association by contiguity. The molecular view has a long history both in early thought about reflexes and in associationism, and, although it was helpful to getting a science of behavior started, it has outlived its usefulness. The molar view stems from a conviction that behavior is continuous, as argued by John Dewey, Gestalt psychologists, Karl Lashley, and others. The molar paradigm views behavior as inherently extended in time and composed of activities that have integrated parts. In the molar paradigm, activities vary in their scale of organization--i.e., as to whether they are local or extended--and behavior may be controlled sometimes by short-term relations and sometimes by long-term relations. Applied to choice, the molar paradigm rests on two simple principles: (a) all behavior constitutes choice; and (b) all activities take time. Equivalence between choice and behavior occurs because every situation contains more than one alternative activity. The principle that behavior takes time refers not simply to any notion of response duration, but to the necessity that identifying one action or another requires a sample extended in time. The molecular paradigm's momentary responses are inferred from extended samples in retrospect. In this sense, momentary responses constitute abstractions, whereas extended activities constitute concrete particulars. Explanations conceived within the molecular paradigm invariably involve hypothetical constructs, because they require causes to be contiguous with responses. Explanations conceived within the molar paradigm retain direct contact with observable variables.

Animals↗
PubMed2006

State and trait related predictors of serum cortisol to DHEA(S) molar ratios and hormone concentrations in schizophrenia patients.

OBJECTIVE: In previous studies we have demonstrated high serum molar ratios of cortisol to dehydroepiandrosterone (DHEA) and its sulfate ester (DHEAS) [together abbreviated DHEA(S)], and the value of both cortisol/DHEA(S) molar ratios for prediction of responsivity to antipsychotic treatment in schizophrenia patients. The present study aimed to examine the contribution of anxiety, and severity of symptoms to the prediction of serum cortisol, DHEA(S) levels and two molar ratios across three examinations. METHOD: Serum concentrations of cortisol and DHEA(S)were examined in 43 schizophrenia inpatients and in 20 age matched healthy controls at baseline, and after 2 and 4 weeks. The Positive and Negative Symptom Scale and the State-Trait Anxiety Inventory scores were used as independent variables for multiple regression analysis. RESULTS: Despite clinical improvement during the study period cortisol/DHEA(S) molar ratios were found persistently elevated as compared to healthy controls. Multiple regression analysis revealed that across three examinations cortisol/DHEA(S) molar ratios negatively associated with trait-anxiety (partial R(2)=7-14%) rather than with negative symptoms (partial R(2)=3-6%). Age and age of onset account for 12.7% for variability of cortisol/DHEAS ratio. Serum cortisol concentrations are predicted by trait and state-anxiety, activation symptoms and daily doses of antipsychotics. A small portion of variability in serum DHEA levels (R(2)=9%) is associated with symptom severity, while DHEAS levels were predicted by age at examination and age of onset. CONCLUSION: Elevated serum cortisol/DHEA(S) molar ratios were attributed to trait-anxiety and age rather than to clinical symptoms. The findings may indicate persistent dysfunction of the hypothalamic-pituitary-adrenal axis that is independent of the patients' clinical state.

Adult↗
PubMed2006

Population systematics of chimpanzees using molar morphometrics.

When dental morphological variation within extant species is used as a guideline to partition variation within fossil samples into species, the underlying assumption is that fossil species are equivalent to extant species. This is the case despite the fact that dental morphology, which is commonly used to differentiate fossil species, is rarely used to differentiate extant species. Aspects of external morphology, ecology, behavior, breeding patterns, and molecular structure that are used to delineate living species are generally not available for fossils. In this paper, the utility of dental evidence for sorting fossil samples into species is evaluated by testing whether molar occlusal morphology is capable of sorting populations of Pan into the species and subspecies already well-established by nondental evidence. The dentitions of 341 chimpanzee individuals, sampled from regions throughout equatorial Africa, were sorted into 16 populations using rivers to demarcate the boundaries between populations. Digital-imaging software was used to measure 15 traits on the occlusal surface of each upper molar and 19 on each lower molar. After applying size adjustments, size-transformed and untransformed variables were subjected to discriminant analysis, with separate analyses carried out for each molar type. Results indicate that populations of Pan troglodytes and Pan paniscus are well differentiated at all molar positions. Populations of P. t. verus are distinct from other populations of P. troglodytes. Populations of P. t. troglodytes and P. t. schweinfurthii show close dental similarity. A distinct population is recognized at the Nigeria-Cameroon border, indicating the presence of P. t. vellerosus. The concordance between the patterns of diversity recognized by this study and other molecular and nonmolecular studies indicates that paleontological species that are similar to species of Pan in terms of size and patterns of diversification may be differentiated using molar morphology.

Africa↗
PubMed1998

Prolactin secretion in molar and normal pregnancy.

OBJECTIVE: To describe the relation between PRL and hCG, T3, T4, fT4, TSH, E2 and P4 levels in normal pregnancies and those complicated with GTD. METHOD: Twenty women, 10 with normal pregnancy and 10 with molar pregnancy were studied. The differences between them and the relation between prolactin (PRL) and human chorionic gonadotropin (hCG), estradiol and thyroid hormones, thyroid stimulating hormone (TSH) and progesterone, was determined by Mann-Whitney U-test and Pearson's correlation coefficient, respectively. RESULTS: HCG, estradiol and thyroid hormones were higher in molar pregnancy, but PRL and progesterone were similar and TSH was lower in molar pregnancy. A negative correlation was found between PRL level and all the hormones in normal pregnancy, with the exception of TSH, and in molar pregnancy there was a positive correlation of PRL with all hormones. CONCLUSION: HCG, E2, T3, T4, fT4 levels were higher in the group with molar pregnancy. Differences in correlation analysis suggest different endocrine regulation mechanisms in molar and normal pregnancies.

Adult↗
PubMed2000

Evaluation of the circadian profiles of serum dehydroepiandrosterone (DHEA), cortisol, and cortisol/DHEA molar ratio after a single oral administration of DHEA in elderly subjects.

Aging is associated with a selective decline in circulating levels of dehydroepiandrosterone (DHEA) and its sulfate, with no major changes in cortisol secretion. In young subjects, serum levels of both DHEA and cortisol are regulated according to a circadian rhythm, and an age-related attenuation of DHEA, but not cortisol, circadian rhythmicity has been reported. Several trials have evaluated the effects of DHEA supplementation in elderly subjects, although the results are still controversial. However, no data are available on the 24-hour profile of DHEA circulating levels in elderly subjects with DHEA administration. In the present study, we evaluated the circadian rhythms of DHEA, cortisol, and the cortisol/DHEA molar ratio in old subjects treated with either placebo (old-PL) or a single 50-mg dose of DHEA (old-D), both administered orally at 0700 hours. For each variable, the circadian profiles were compared with those obtained in young control subjects. The group of young subjects displayed a circadian rhythm for both DHEA and cortisol serum concentrations but no rhythm for the cortisol/DHEA molar ratio. In the old-PL group, the circadian rhythm of DHEA was completely abolished, whereas significant rhythms for both cortisol and the cortisol/DHEA molar ratio were observed. Particularly, at each time point, the cortisol/DHEA molar ratio was significantly higher in these subjects versus the young group. In the old-D group, the circadian rhythm of DHEA was completely restored and was comparable to that observed in the young group. Analogous to the observations in young subjects, the profile of the cortisol/DHEA molar ratio in old-D subjects did not display any circadian rhythmicity, the values being almost completely comparable to those observed in young controls. Our data demonstrate that the circadian rhythm of DHEA is totally abolished in elderly subjects. A single 50-mg dose of DHEA administered orally at 0700 hours restores the circadian rhythmicity of serum DHEA and almost completely normalizes the 24-hour profile of the cortisol/DHEA molar ratio in old subjects without affecting the cortisol circadian rhythm.

Administration, Oral↗
PubMed1995

A clinical investigation of the correction of unilateral first molar crossbite with a transpalatal arch.

The correction of a unilateral first molar crossbite with a Goshgarian type of transpalatal arch was evaluated in 35 children from 6 years, 8 months to 15 years, 11 months old. Fifteen of the children were treated with an arch activated for expansion only and 20 children with an arch activated in a similar way but with the inclusion of buccal root torque of the anchorage tooth. With both types of activation, the arches worked in a statically determinate system, i.e., the tooth in crossbite was allowed to tip buccally. The movements of the first molars as a result of the treatment were monitored by measurements on dental casts and frontal cephalometric roentgenograms. In addition, the width of the midpalatal suture was measured on occlusal roentgenograms of the maxilla. In the children treated with an arch activated only for expansion, the molars on both sides of the dental arch moved buccally during the treatment. In the children treated by torque activation, on the other hand, there was a considerable buccal movement of the molar on the side of the crossbite without any significant buccal movement of the anchorage tooth. In individual cases, the molar on the noncrossbite side moved and tipped palatally and in some cases buccally but to a minor degree. With both types of activation, there was only a slight change in inclination of the transverse occlusal plane through the first molars; the plane opened up slightly toward the side of the crossbite. For both types of activation, there was a slight widening of the palatal suture during the treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1999

An ultrastructural study of the effects of bisphosphonate administration on osteoclastic bone resorption during relapse of experimentally moved rat molars.

This study was designed to clarify the effects of systemic administration of bisphosphonate, pamidronate, on the bone resorbing activity of osteoclasts during relapse of rat molars, after experimental movement. An elastic band was inserted between the upper first and second molars of 7-week-old rats and removed 21 days later. At 1 day before elastic band removal, bisphosphonate was administered via a tail vein. After elastic band removal, the rats were further maintained for 0, 5, or 10 days. The relapse of the first molars was studied by means of light and scanning-electron and transmission-electron microscopy. When an elastic band was removed, the mean interdental distance between the first and second molars in all rats was approximately 435 micrometer. In the control rats, it had decreased to 108 micrometer by day 5 and 57 micrometer by day 10. In these control rats, numerous osteoclasts appeared along the alveolar bone surface in the compressed side of the periodontal ligament of first molars. Administration of bisphosphonate significantly inhibited the prominent decrease in interdental distance. In these rats, it averaged 313 micrometer at day 5 and 115 micrometer at day 10. In bisphosphonate-treated rats, osteoclasts aggregated mainly in vascular canals of alveolar bone but were occasionally observed along the alveolar bone surfaces facing the periodontal ligament. Administration of bisphosphonate also induced structural changes, such as disappearance of ruffled borders and cytoplasmic polarity, in osteoclasts. A degenerated osteoclast was also observed in a bisphosphonate-treated rat. However, bisphosphonate induced no structural changes in osteoblasts, osteocytes, or periodontal ligament fibroblasts. These results suggest that a single systemic administration of bisphosphonate decreases the extent of initial relapse in experimentally moved rat molars via a mechanism involving impairment of the structure and resorptive functions of osteoclasts.

Alveolar Bone Loss↗