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PubMed2005

[Transient intestinal obstruction due to stool impaction in the elderly].

BACKGROUND/AIMS: Acute intestinal obstruction is an urgent disease to be diagnosed and treated promptly. In elderly, fecal impaction may be an important and preventable cause of colonic obstruction. We investigated the clinical features of patients presenting with identical features of intestinal obstruction transiently due to fecal impaction. METHODS: From February 2001 to March 2004, nineteen patients were diagnosed as transient intestinal obstruction due to fecal impaction. We evaluated clinical characteristics, radiologic findings, sigmoidoscopic or colonoscopic findings and managements. RESULTS: Male and female ratio was 1:1.1. Mean age was 79.3 years. All 19 patients had abdominal pain and distension. On digital rectal examination, the hard feces was palpable in only 8 patients (42%) while others showed empty rectum. The abnormal laboratory findings included leukocytosis in 5 patients (26%), anemia in 10 patients (53%) and electrolyte abnormalities in 7 patients (37%). Simple abdominal X-rays showed diffuse small and/or large bowel dilatations. In only 3 patients (16%) air-fluid levels were definite, but most patients showed abundant feces in the rectum and colon. During emergency sigmoidoscopy, abdominal pain and distension were relieved and there were Bristol type 1 hard stool in the recto-sigmoid junction in 7 patients (37%) and multiple rectal ulcers in 1 patient. On colonoscopy, there were no mass or pathologic obstruction in all patients. Patients were discharged after the adequate medication and toilet training. CONCLUSIONS: In elderly patients, fecal impaction is odd and preventable cause of intestinal obstruction. It is often significant to differentiate fecal impaction from other pathologic conditions in patients with chronic constipation.

Aged↗
PubMed1997

Spatio-temporal grouping for the formation of vascular segments in coronarography image sequences.

This work is aimed at the extraction of vascular structures using perceptual grouping methods. The approach is based on structural feature matching, between images in the time sequence. These features correspond to junctions (or bifurcation points) and are paired by means of a local criteria. A global refinement procedure is then applied by means of a relaxation scheme. The feature trajectories over the entire image sequence are examined to further build sets of vascular segments, which better describe vascular branches. The resulting performances are exemplified on a standard biplane coronarographic examination.

Angiography, Digital Subtraction↗
PubMed2001

Outline and arrangement of enamel rods in human deciduous and permanent enamel. 3D-reconstructions obtained from CLSM and SEM images based on serial ground sections.

Human enamel rods were made visible continuously from the dentino-enamel junction (DEJ) up to the enamel surface. From 12 teeth (1st and 2nd dentition) enamel blocks from the cervical third were prepared with perpendicular planes, embedded in resin, and ground down in steps of 15 microm parallel to the enamel surface. Enamel rods were made visible by acid etching (35% H3PO4, 45 s), sputtered and examined in the scanning electron microscope (SEM). Prior to this, the enamel blocks were viewed under the CLSM and optical sections at distances of 2 microm were obtained, starting in the same plane as the grinding surface. The outlines of the rods were digitized and reconstructed three dimensionally. For the first time, the path of single and grouped enamel rods on their way through the entire enamel layer was depicted. 3D images obtained from confocal laser scanning microscopy (CLSM) data were similar to those gained from SEM images. Single rods did not maintain their same outline throughout their path; arcade outlines predominated close to the DEJ, while keyhole outlines prevailed at the enamel surface. Within a group of rods, neighborhood relations changed, and neighbor rods influenced their outlines mutually, including the variable extent of the tail. The interdependence between the plasticity of the rods and the ameloblasts' forms should be topics of further research.

Dental Enamel↗
PubMed1985

Structural junctions in DNA: the influence of flanking sequence on nuclease digestion specificities.

When a protein binds to DNA, the affinity of this protein for its primary site of interaction may be influenced by the nature of flanking sequences. This is thought to be a consequence of local cooperativity in the DNA molecule, where the conformation at one point along the helix can influence the conformation at another, and thereby modulate the free energy of protein-DNA recognition. In order to learn more about this process, we have carried out experiments of two sorts. First, we have constructed sequences of the type (dA)11 (dG)8, where the conformational preferences of the DNA molecule switch from one extreme to another over just a single base pair, and subjected them to digestion by DNAase I and DNAase II. This is to learn whether the structure changes abruptly at the junction point, or more gradually with an influence extending into residues on either side. Secondly, we have subjected long plasmid DNA to digestion by restriction enzymes Fnu DII, Hae III, Hha I and Msp I, to look for correlations between cutting rate and the identity of nucleotides on either side of the restriction site. The influence of flanking sequence on nuclease digestion specificities is clearly evident in both kinds of experiment, but the rules governing this seem complex and not easily formulated. The best that can be done at present is to divide the problem into two parts, "analogue" and "digital", representing sugar-phosphate and base components of recognition.

Base Sequence↗
PubMed1993

Caries inhibition by fluoride-releasing primers.

This study evaluated the caries inhibition of dentin primers with the addition of fluoride. Two standardized Class V preparations were placed in 20 molars, the gingival margin placed below the cementoenamel junction and the occlusal margin placed in enamel. Two dentin primers (Syntac and ScotchPrep) were placed in equal numbers of 20 preparations, according to manufacturer's instructions. Ammonium fluoride (10% by weight) was then added to these primers and they were placed in the remaining 20 preparations, opposing the non-fluoridated primer of the same system. All teeth were then restored with a non-fluoridated resin composite. All teeth were subjected to an artificial caries challenge (pH 4.2) for 5 days. Sections of 100 microns were obtained, photographed under polarized light microscopy, then demineralized areas were quantitated by digitization. Results demonstrated the mean areas (mm2 +/- S.D.) demineralization at 0.25 mm, 0.5 mm and 1.0 mm from the restoration margin to be: Syntac/fluoride (1.44 +/- 0.49, 1.68 +/- 0.54, 3.72 +/- 0.74); Syntac (1.99 +/- 0.58, 1.50 +/- 0.35, 2.98 +/- 1.26); ScotchPrep/fluoride (1.23 +/- 0.68, 1.55 +/- 0.64, 3.08 +/- 1.16); ScotchPrep (1.90 +/- 0.83, 1.71 +/- .038, 3.36 +/- 0.62). A paired t-test indicated primers with fluoride to demonstrate significantly less demineralization 0.25 mm from the restoration margin (P < 0.07).

Composite Resins↗
PubMed1996

Intercellular calcium waves in rat pancreatic acini: mechanism of transmission.

Digital-imaging microfluorimetry, together with microinjection of marker/messenger molecules, was utilized to investigate intercellular Ca2+ signaling in rat pancreatic acinar cells. Stimulation of acini with low concentrations of secretagogues [< 100 pM cholecystokinin (CCK), < 1 microM carbachol (CCh)] resulted in asynchronous but coordinated increases in Ca2+ that appeared to pass in a "wavelike" fashion between cells. In contrast, at higher supermaximal concentrations of agonists (> 300 pM CCK, > 1 microM CCh), which induce a large "peak-and-plateau" intracellular Ca2+ signal, all cells in the acinus appeared to increase Ca2+ concentration ([Ca2+]) in synchrony. Microinjection of lissarhodamine, a marker of gap-junctional permeability, into cells previously loaded with fura 2 allowed the simultaneous measurement of gap-junctional coupling and [Ca2+]. Stimulation with supermaximal concentrations of agonists resulted in the attenuation of junctional permeability, whereas, during stimulation with physiological concentrations of agonist, junctional communication remained operable. Injection of inositol 1,4,5-triphosphate [Ins(1,4,5)P3] into one cell of an acinar cluster resulted in the generation of a Ca2+ signal in the injected cell and adjacent cells. In contrast, injection of CaCl2 itself did not result in propagation of the signal. When CaCl2 was injected into cells that had been previously stimulated with a threshold concentration of CCK, propagation of a signal was observed between cells. On the basis of these data, a model is proposed in which Ca2+ acts as coagonist with Ins(1,4,5)P3 to potentiate the Ca(2+)-releasing action of Ins(1,4,5)P3 and, by diffusion of the two molecules through gap junctions, underlies intercellular signaling in acinar cells. Gap-junctional communication may be an important factor in amplifying a threshold signal produced in one cell throughout the acinus, resulting in enhanced stimulated secretion in acinar preparations compared with preparations of isolated cells.

Animals↗
PubMed2003

Moment arms about the carpal and metacarpophalangeal joints for flexor and extensor muscles in equine forelimbs.

OBJECTIVE: To determine whether muscle moment arms at the carpal and metacarpophalangeal joints can be modeled as fixed-radius pulleys for the range of motion associated with the stance phase of the gait in equine forelimbs. SAMPLE POPULATION: 4 cadaveric forelimbs from 2 healthy Thoroughbreds. PROCEDURE: Thin wire cables were sutured at the musculotendinous junction of 9 forelimb muscles. The cables passed through eyelets at each muscle's origin, wrapped around single-turn potentiometers, and were loaded. Tendon excursions, measured as the changes in lengths of the cables, were recorded during manual rotation of the carpal (180 degrees to 70 degrees) and metacarpophalangeal (220 degrees to 110 degrees) joints. Extension of the metacarpophalangeal joint (180 degrees and 220 degrees) was forced with an independent loading frame. Joint angle was monitored with a calibrated potentiometer. Moment arms were calculated from the slopes of the muscle length versus joint angle curves. RESULTS: At the metacarpophalangeal joint, digital flexor muscle moment arms changed in magnitude by < or = 38% during metacarpophalangeal joint extension. Extensor muscle moment arms at the carpal and metacarpophalangeal joints also varied (< or = 41% at the carpus) over the range of joint motion associated with the stance phase of the gait. CONCLUSIONS AND CLINICAL RELEVANCE: Our findings suggest that, apart from the carpal flexor muscles, muscle moment arms in equine forelimbs cannot be modeled as fixed-radius pulleys. Assuming that muscle moment arms at the carpal and metacarpophalangeal joints have constant magnitudes may lead to erroneous estimates of muscle forces in equine forelimbs.

Animals↗
PubMed2006

Controlling the energy transfer in dipole chains.

Processing digital signals on the molecular scale is of great interest. In this paper, we discuss the control of pulselike energy propagation through one-dimensional arrays of dipoles. Three systems are explored. In the first system, a chain of coaxial dipoles is gated by two control dipoles. Changing the orientation of these control dipoles lets us control the transfer of energy in the chain. In the other two systems, the chain-branch system and the two-branch system, two chains are used as an input and the propagation of energy is controlled by sending one or two signals toward the junction. Both systems can operate as a logical AND port. Their geometrical configurations are key to a well-defined control and operation of the AND port.

Journal Article↗
PubMed1991

Diameter and wall thickness recording of canine pylorus with implantable miniature ultrasonic transducers.

Outer diameter and thickness of the muscular wall of canine pylorus were measured simultaneously by determining the distance between pairs of implanted ultrasonic transducers, evaluating the sonic transit time with a digital sonometer. For the study of the motility in the gastroduodenal transit zone, the ultrasonically determined pyloric responses were compared with signals from conventional strain-gauge transducers sutured to the neighboring duodenum and gastric antrum. After stimulation of the gastrointestinal motility by an intravenous bolus injection of cholecystokinin octapeptide, pyloric contractions with a frequency of 5.2 min-1 could be recorded for some minutes; those contractions were independent of the more rapid antral and duodenal motility. Together with the observed tonic constriction of the pyloric ring, which could be inhibited by intravenous injection of adrenaline, an autonomous role of the gastroduodenal junction as a true sphincter is supported.

Animals↗
PubMed2001

Digital topological analysis of in vivo magnetic resonance microimages of trabecular bone reveals structural implications of osteoporosis.

Osteoporosis is a disease characterized by bone volume loss and architectural deterioration. The majority of work aimed at evaluating the structural implications of the disease has been performed based on stereologic analysis of histomorphometric sections. Only recently noninvasive imaging methods have emerged that provide sufficient resolution to resolve individual trabeculae. In this article, we apply digital topological analysis (DTA) to magnetic resonance microimages (mu-MRI) of the radius obtained at 137 x 137 x 350 microm3 voxel size in a cohort of 79 women of widely varying bone mineral density (BMD) and vertebral deformity status. DTA is a new method that allows unambiguous determination of the three-dimensional (3D) topology of each voxel in a trabecular bone network. The analysis involves generation of a bone volume fraction map, which is subjected to subvoxel processing to alleviate partial volume blurring, followed by thresholding and skeletonization. The skeletonized images contain only surfaces, profiles, curves, and their mutual junctions as the remnants of trabecular plates and rods after skeletonization. DTA parameters were compared with integral BMD in the lumbar spine and femur as well as MR-derived bone volume fraction (BV/TV). Vertebral deformities were determined based on sagittal MRIs of the spine with a semiautomatic method and the number of deformities counted after threshold setting. DTA structural indices were found the strongest discriminators of subjects with deformities from those without deformities. Subjects with deformities (n = 29) had lower topological surface (SURF) density (p < 0.0005) and surface-to-curve ratio (SCR; a measure of the ratio of platelike to rodlike trabeculae; p < 0.0005) than those without. Profile interior (PI) density, a measure of intact trabecular rods, was also lower in the deformity group (p < 0.0001). These data provide the first in vivo evidence for the structural implications inherent in postmenopausal osteoporosis accompanying bone loss, that is, the conversion of trabecular plates to rods and disruption of rods due to repeated osteoclastic resorption.

Adult↗
PubMed2005

Classification, reproducibility and prevalence of root proximity in periodontal patients.

AIM: The primary aim of this study is to define and classify root proximity. The secondary aim is to examine the reproducibility of the measurement tools, to study the prevalence per inter-dental area and to examine whether the distance from the cemento-enamel junction (CEJ) to the bone crest (BC) differs between sites with root proximity and their contra-lateral sites without root proximity. MATERIAL AND METHODS: In order to indicate the location of root proximity, a modification of the Shei ruler was developed, dividing the roots into three equal parts. A radiographic template was used to measure the distance between the roots, in this way determining the severity of the root proximity. The reproducibility of the measurement tool was tested, the prevalence was calculated and the distances CEJ-BC for root proximity sites and contra-lateral sites were recorded. RESULTS: A two-digit classification was obtained dividing the root into three locations [apical (A), between (B) and coronal (C)], with each location having the possibility of three different severities of root proximity. The described modification of the Shei ruler and the measurement tool for the severities can be considered as reproducible measurement tools. Root proximity was most prevalent in maxillary molars and between central and lateral incisors in the maxilla and mandible. There was no difference in CEJ-BC distance between the root proximity sites and their contra-lateral sites. CONCLUSION: We can conclude that a two-digit classification for root proximity was established. Root proximity in untreated periodontal patients has no influence on the distance CEJ-BC. However, the location of root proximity becomes important from the moment that periodontal disease has been established at that site. The severity of root proximity is important for choosing treatment options. There is a striking similarity between bone loss patterns and tooth loss and the location of inter-dental spaces where root proximity is most prevalent.

Adolescent↗
PubMed1996

Aneurysm of the internal auditory artery: our experience and review of the literature.

The aneurysms of the internal auditory artery (IAA) situated distal from anterior inferior cerebellar artery (AICA)-IAA junction, are extremely rare lesions. A case of distal aneurysm if IAA is presented causing subarachnoid haemorrhage (SAH) and complete ipsilateral deafness. After the neurosurgical treatment the hearing of the patient definitely improved. The literature of distal aneurysms of AICA is reviewed focusing on the clinical features of these malformations, causing cerebello-pontine angel (CPA) symptoms with or without SAH.

Aneurysm, Ruptured↗
PubMed2002

Acetylcholine-induced zymogen granule exocytosis: comparison between acini and single pancreatic acinar cells.

INTRODUCTION: Numerous studies have been carried out on the agonist-evoked calcium responses of single pancreatic acinar cells; however, several reports have shown that dissociation of the exocrine pancreas into predominantly single cells has an adverse effect on agonist-evoked amylase secretion. AIMS AND METHODOLOGY: To determine whether single acinar cells behave in an anomalous manner compared with cells within an intact acinus, we measured exocytosis in both single acinar cells and acini (2-5 cells) present in the same preparation. Exocytosis of individual zymogen granules was quantified in real-time by using the technique of continuous time-differential analysis of brightfield digital images. RESULTS: Basal rates of exocytosis were low in both single cells and intact acini. Application of 10 microM acetylcholine for 6 minutes stimulated a biphasic secretory response in acinar cells. Additionally, we found that exocytotic events occur repetitively in specific locations within the apical domain; i.e., there are exocytotic "hot spots." There were no statistically significant differences between the exocytotic rates, nor were there any differences in the characteristics of the exocytotic hot spots of single cells compared with those of acini. CONCLUSION: We conclude that time-differential analysis of brightfield images appears to be a useful tool for the investigation of the role of gap junctions in zymogen granule exocytosis and that single acinar cells provide a reasonable model for studies of acinar cell signaling and secretion.

Acetylcholine↗
PubMed1979

Quantitative analysis of intermediary metabolism in Tetrahymena. Cells grown in proteose-peptone and resuspended in a defined nutrient-rich medium.

Tetrahymena pyriformis were grown to early-stationary phase and resuspended in a defined mixture containing glucose, fructose, ribose, glycerol, acetate, pyruvate, bicarbonate, glutamate, and hexanoate, with only one substrate labeled with 14C in any flask. Incorporation of label into CO2, glycogen, RNA, alanine, glutamate, glycine, lipid glycerol, and lipid fatty acids was measured 20, 40, and 60 min after the start of the incubation. To develop a model suitable for quantitative analysis of the data, it was necessary to join two preceding models, one for carbohydrate-metabolizing cells and one for acetate-metabolizing cells, eliminating the over-simplified sections of each. Equations were written and programmed for a digital computer to allow computation of the amount of label expected to be incorporated into any of the products measured for any given set of steady state flux values in the metabolic network. The model formed by simply joining the two preceding models did not yield satisfactory agreement with the complete data obtained in the present study, although each partial set of data could be fit well by the appropriate partial model. Analysis of the ways in which the model failed to yield good fits to the data indicated that another pool of P-enolpyruvate, of pyruvate, and of acetyl-CoA had to be added at the junction of the two models. The presence of such poolte into fatty acids as compared to the incorporation of label from glucose into fatty acids. A new model was therefore constructed which differed from the preceding model only in its structural organization at the level of P-enolpyruvate, pyruvate, and acetyl-CoA. The model is consistent with all known information on the compartmental structure of metabolism in Tetrahymena, on enzyme localization, and on the enzyme complement of this cell. Over 70 measurements of label incorporation into products were made at each time. These, plus a large number of "limit" measurements which constrain any possible solutions, were in sufficient excess of the 39 independent flux values to permit a stringent assessment of the model. A set of flux values was found which yielded a good fit to the data. These flux values therefore provide a quantitative description of metabolite flux in the intact cell during the slow adaptation to the nine-substrate mixture. The rates of utilization of glucose, fructose, glycerol, and ribose were in the ratio of about 10:1:0.33:0.16, i.e. fairly similar to the ratio observed with carbohydrate-metabolizing cells. Initial flux through phosphofructokinase is about 160 nmol/10(6) cells.h, increasing over 3-fold during tje jpir incubation. Initial flux through fructose-1,6-diphosphatase is about 110 nmol/10(6) cells.h and also increases almost 3-fold during the incubation. Thus net flux is glycolytic and increases 4-fold during the hour with a large amount of futile cycling at this step...

Acetates↗
PubMed2004

Construction of realistic branched, three-dimensional arteries suitable for computational modelling of flow.

Routinely performed biplane digital coronary angiograms were used to construct a three-dimensional model of the coronary arteries. The technique took the images and automatically picked the centreline and radii in each. By reading the information contained in the DICOM format, the rotation angle between the two images could be ascertained, and the centreline in three dimensions could be determined. Once the centreline and radii had been calculated, a finite volume mesh of the artery was constructed that could be used as input into a fluid dynamics package that solves Navier-Stokes equations. A four-section method was adopted for constructing the mesh, utilising three tubular segments and a small junction section. The tubes were constructed automatically, and the junction procedure was semi-automated, maximising user-control over this region. A structured mesh was used for the tubes, and an unstructured mesh was used to model accurately the irregular shape of the junction. The accuracy of the reconstruction method was established by projection of a mesh onto an independent image of the same artery and the use of a coronary phantom. These tests, along with calibration of the edge detection, established an error of less than 2% in the model.

Coronary Angiography↗
PubMed2005

Evidence of transcellular albumin transport after hemorrhagic shock.

Hemorrhagic shock-induced ischemia-reperfusion injury is characterized by an increase in microvascular permeability. This increase in permeability is thought to occur mainly via passive transport through interendothelial cell junctions. However, recent data have suggested that a transcellular (caveolae) transport mechanism(s) may also play a role after shock. The purpose of our study was to investigate the role of caveolae transport after hemorrhagic shock. After a control period, blood was withdrawn to reduce the mean arterial pressure to 40 mmHg for 1 h in urethane-anesthetized Sprague-Dawley rats. Mesenteric postcapillary venules in a transilluminated segment of small intestine were examined to determine changes in permeability. Rats received an intravenous injection of fluorescein isothiocyanate-bovine albumin during the control period. The fluorescent light intensity emitted from the fluorescein isothiocyanate-bovine albumin was recorded with digital microscopy within the lumen of the microvasculature and was compared with the intensity of light in the extravascular space. The images were downloaded to a computerized image analysis program that quantitates changes in light intensity. This change in light intensity represents albumin extravasation. Our results demonstrated a marked increase in albumin leak after hemorrhagic shock that was significantly attenuated with two different inhibitors of transcellular transport, N-ethylmaleimide and methyl-beta-cyclodextrin. These data suggest that caveolae transport plays a significant role in microvascular permeability after hemorrhagic shock.

Albumins↗
PubMed1988

Localization of neural cell adhesion molecule in denervated muscle to both the plasma membrane and extracellular compartments by immuno-electron microscopy.

The location of neural cell adhesion molecule in mouse skeletal muscle has been investigated using two immuno-electron microscopical techniques. In the first method, 6-micron frozen sections of a normal and a hemi-denervated gluteus muscle were stained by an indirect immunoperoxidase method using a rabbit-derived polyclonal antiserum to neural adhesion molecule as the primary antibody. The stain was visualized with the electron-dense chromogen, diaminobenzidine and the sections fixed, osmicated and processed for electron microscopy whilst still on the slide. Ultrathin sections were cut and viewed in the electron microscope, where the reaction product appeared to be localized in the plasma membrane and on the basal lamina of the muscle fibres. The second method, using a 5-nm immunogold-labelled secondary antibody, confirmed and extended these initial observations. In these experiments, the primary antibody to neural cell adhesion molecule was applied in vivo to hemi-denervated mouse gluteus muscles. The muscles were dissected out 24 h later, divided into denervated and innervated halves and then into junctional and extrajunctional regions. Together with the junctional and extrajunctional regions of normal, control pieces of muscle which had not been incubated with anti-neural cell adhesion molecule, they were lightly fixed, and incubated with the secondary gold-labelled antibody, before further fixation and processing for electron microscopy. Semi-thin, 0.5-micron sections of each were cut and viewed at 20,000 x magnification. Randomly sampled fibres from the extrajunctional regions of the denervated and innervated halves of the hemi-denervated gluteus and the normal, control gluteus were photographed for quantitative analysis. Five micrographs were randomly selected from each group and in these, the numbers, density and position of gold particles were measured using a digitizing tablet. By far the highest number of gold particles was found in the denervated half of the gluteus muscle, there being much less in the innervated half and practically none in the control. The density of gold particles in the denervated muscles was maximal in the plasma membrane-basal lamina complex, but most were located in the extracellular spaces outside this region, where they usually occurred in clusters apparently in association with collagen fibres. We conclude that neural cell adhesion molecule in denervated skeletal muscle is present not only in the plasma membrane but also in the basal lamina and extracellular space.

Animals↗
PubMed1992

A computer-assisted method for making linear radiographic measurements using stored regions of interest.

Accurate detection of changes in alveolar bone height requires radiographic measuring methods with a reliability of standard deviation (SD) of 0.15 mm or better. No periodontal digital imaging system has reached this reliability, although 3 analogue methods have achieved this goal. However, existing linear methods are time-consuming, difficult to use, unsuitable for measuring all possible (unsharp) anatomical sites and do not provide a confidence estimate for sites of change observed in serial standardized films. A rapid computer-assisted method using stored image regions of interest (ROI) has been developed which allows retest measurements for all possible sites and automatically calculates a 90%, 95%, 98%, or 99% confidence threshold value, derived from duplicate measurement variation, for sites of apparent crest height change. 28 examiners, with minimal training in operating the system, measured 14 different cement-enamel junction to crest height distances from a standard bitewing image, with and without the ROI method. The measurements were repeated 4 weeks later. 13/14 sites achieved an intra-examiner SD threshold of less than or equal to 0.15 mm with the ROI method but 0/14 without. A higher inter-examiner SD threshold of less than or equal to 0.22 mm was achieved for 13/14 sites using ROI and 0/14 without (p less than 0.001). The measurement of crest height changes in a region of previous severe vertical bone loss is demonstrated using serial films. The potential for using trabecular bone patterns as reference sites in regions where traditional measurement points are absent is demonstrated.(ABSTRACT TRUNCATED AT 250 WORDS)

Alveolar Bone Loss↗