Effect Of Section Thickness Research Articles

Effect of section thickness and build orientation on tensile properties and material characteristics of laser sintered nylon‐12 parts

PurposeThe purpose of this paper is to describe work carried out as part of a £350,000 project aimed at improving understanding of polymer sintering processes. This particular package of research was performed in order to identify the effects of different section thicknesses (and therefore different thermal conditions) in parts produced by laser sintering (LS), on the resultant mechanical properties of these parts.Design/methodology/approachLaser sintered nylon‐12 parts were produced in a range of thicknesses between 2 and 6 mm, and in three different orientations, to identify the effects of each on the tensile properties of these parts.FindingsResults indicated that, at any of the orientations tested, the section thickness had no significant effect on any of the main tensile properties, or on the repeatability of these properties. Crucially, this is in direct contradiction with the trends identified previously in this project, whereby changes in section thickness have been shown to correlate with changes in fracture toughness.Research limitations/implicationsFurther work could investigate a wider range of section thicknesses or geometries, in order to continue building a more complete picture of the effects of geometry on laser sintered part properties.Practical implicationsThese results are directly applicable to designers using, or wishing to use, LS to manufacture their products.Originality/valueWhilst there is a large range of published literature on the effects of processing parameters on mechanical properties of laser sintered parts, and on the resolution and accuracy achievable with these, there is minimal information available on the effects of geometry on mechanical properties. This paper therefore represents a novel addition to the global LS knowledge base.

Comparison of Grossmann and lumped heat capacitance methods for assessment of heat transfer characteristics of quench media

The suitability of Grossmann and lumped heat capacitance (LHC) methods for estimation of quench severity of nanofluids, brine solutions and a laboratory detergent based medium was investigated. The study involved the assessment of the effect of section thickness of the probe on heat transfer coefficients for different quench media. Computer aided cooling curve analysis during quenching of type 304 stainless steel probes was carried out. The measured thermal history data were used to estimate heat transfer coefficients by Grossmann and LHC methods. The LHC method based on a 10 mm diameter stainless steel probe was found to be applicable for characterising media having quench severity less than 20 m−1. Although Grossmann method is based on the concept of average heat transfer coefficient, it can be used for quench media having varying severity of quenching. Grossmann method is found to be more sensitive to the effect of section thickness on heat transfer.

Effects of CT Section Thickness and Reconstruction Kernel on Emphysema Quantification: Relationship to the Magnitude of the CT Emphysema Index

Computed tomography (CT) section thickness and reconstruction kernel each influence CT measurements of emphysema. This study was performed to assess whether their effects are related to the magnitude of the measurement. Low-radiation-dose multidetector CT was performed in 21 subjects representing a wide range of emphysema severity. Images were reconstructed using 20 different combinations of section thickness and reconstruction kernel. Emphysema index values were determined as the percentage of lung pixels having attenuation lower than multiple thresholds ranging from -960 HU to -890 HU. The index values obtained from the different thickness-kernel combinations were compared by repeated measures analysis of variance and Bland-Altman plots of mean versus difference in all subjects, and correlated with quantitative histology (mean linear intercept, Lm) in a subset of resected lung specimens. The effects of section thickness and reconstruction kernel on the emphysema index were significant (P < .001) and diminished as the index attenuation threshold was raised. The changes in index values from changing the thickness-kernel combination were largest for subjects with intermediate index values (10%-30%), and became progressively smaller for those with lower and higher index values. This pattern was consistent regardless of the thickness-kernel combinations compared and the HU threshold used. Correlations between the emphysema index values obtained with each thickness-kernel combination and Lm ranged from r = 0.55-0.68 (P = .007-.03). The effects of CT section thickness and kernel on emphysema index values varied systematically with the magnitude of the emphysema index. All reconstruction techniques provided significant correlations with quantitative histology.

Dependence of computed tomography volume measurements upon section thickness: An application to human dry skulls

Estimation of intracranial volume (ICV) using computed tomography (CT) scans has previously been described. However, we were not able to identify a gold standard study that analyzed the effect of section thickness on the estimation of ICV. Therefore, we conducted the present study, scanning five dry skulls in the coronal and axial planes using a multislice CT machine (Toshiba TSX-101A, Aquilion 16 Slice, Tochigi, Japan). Consecutive sections of variable thicknesses of 2, 3, 5, 7, and 10 mm, respectively, were used to estimate ICV by means of the planimetry method of the Cavalieri principle. All estimations were done by the same observer. However, the estimated volumes did not concur with the actual volumes of the skulls as determined by the fluid displacement technique (P < 0.05). In fact, results revealed that the section thicknesses created over- or under-projection effects for the estimated volumes. The results were analyzed to reveal the deviation principles of the estimates based on section thickness. Prediction formulas were calculated to estimate the deviation percentage of the ICV depending on section thickness and section plane. Ultimately, the results showed that the effect of section thickness on ICV estimates could not be overlooked, but that the values obtained could be corrected using the proposed prediction formulas presented in this study.

Effect of section thickness on creep and stress rupture behaviour of DS CM247 nickel base superalloy

The effect of section thickness on creep and stress rupture behaviour of DS CM247 nickel base superalloy at three temperatures viz. 760, 982 and 1038°C, has been investigated in an effort to identify the factors contributing to the observed creep/stress rupture behaviour. Irrespective of section thickness, the shape of creep curves at the lowest temperature of 760°C differs from the shape of those at the higher temperatures, showing significantly higher primary creep strain (PCS). At higher temperatures the creep curves exhibit limited primary and secondary regimes, but predominant tertiary regime. Such a difference in shapes of the creep curves is related to the difference in dislocation bypass mechanisms operating at these temperatures. The variation of minimum creep rate (MCR) and time to rupture (tf) with section size indicates a progressive creep strengthening at 760 and 982°C, while a progressive creep weakening at 1038°C with decreasing specimen thickness. Such a behaviour can be explained in terms of relative extents of the surface oxide layer (contributing to creep strengthening) and γ′ depleted zone (causing creep weakening) formed at these temperatures. Further, the creep strengthening at 760 and 982°C as well as weakening at 1038°C is more pronounced for the thinner specimens.

Effect of section thickness on creep and stress rupture behaviour of DS CM247 nickel base superalloy

The effect of section thickness on creep and stress rupture behaviour of DS CM247 nickel base superalloy at three temperatures viz. 760, 982 and 1038°C, has been investigated in an effort to identify the factors contributing to the observed creep/stress rupture behaviour. Irrespective of section thickness, the shape of creep curves at the lowest temperature of 760°C differs from the shape of those at the higher temperatures, showing significantly higher primary creep strain (PCS). At higher temperatures the creep curves exhibit limited primary and secondary regimes, but predominant tertiary regime. Such a difference in shapes of the creep curves is related to the difference in dislocation bypass mechanisms operating at these temperatures. The variation of minimum creep rate (MCR) and time to rupture (tf) with section size indicates a progressive creep strengthening at 760 and 982°C, while a progressive creep weakening at 1038°C with decreasing specimen thickness. Such a behaviour can be explained in terms of relative extents of the surface oxide layer (contributing to creep strengthening) and γ′ depleted zone (causing creep weakening) formed at these temperatures. Further, the creep strengthening at 760 and 982°C as well as weakening at 1038°C is more pronounced for the thinner specimens.

Micro–macro interactions and effect of section thickness of hpdc AZ91 Mg alloy

This work is aimed to conclude the effect of section thickness of a high pressure die cast (hpdc) Mg alloy on the tensile properties as ambiguous conclusions are presented in the literature. Tensile tests were performed on as-cast hpdc AZ91 alloy and the effect of section thickness on the tensile properties such as yield strength (YS), ultimate tensile strength (UTS), ductility and fracture strain (FS) are explained. Additionally, explanation on the microfailure mode of the material is presented to explain the influence of different microfeatures on the failure process. The average size, area fraction and clustering tendency of pores and Mg 17 Al 12 (β) particles as well as average grain size are quantified and their effects on section thickness are obtained. The results confirm that the UTS, YS, ductility and FS are mainly influenced by the area fraction, size distribution and spatial arrangement of pores and phases.

Pulmonary Emphysema: Radiation Dose and Section Thickness at Multidetector CT Quantification—Comparison with Macroscopic and Microscopic Morphometry

To prospectively investigate the effects of radiation dose and section thickness on quantitative multidetector computed tomographic (CT) indexes of pulmonary emphysema. The institutional review board approved this protocol. Written informed consent was obtained from all patients. Seventy patients (49 men, 21 women; age range, 38-79 years) referred for surgical resection of a lung tumor underwent multidetector CT with 4 x 1-mm collimation, 120 kVp, and 20 and 120 effective mAs. At each radiation dose, 1.25-, 5.0-, and 10.0-mm-thick sections were reconstructed at 10-mm intervals. From scans of the lobe or whole lung to be resected, relative areas (RAs) of lung with attenuation coefficients lower than nine thresholds and eight percentiles of the distribution of attenuation coefficients were compared with the histopathologic extent of emphysema, which was measured microscopically--by using the corrected mean interwall distance (MIWD) and the corrected mean perimeter (MP)--and macroscopically. Correlations between the data obtained by using attenuation thresholds and percentiles and the parameters macroscopic extent of emphysema, MIWD, and MP were investigated by using Spearman coefficients. The 1st percentile (r range, -0.394 to -0.675; P < .001) and attenuation coefficients of -980, -970, and -960 HU (r range, 0.478-0.664; P < .001) yielded the strongest correlations with macroscopic extent, MIWD, and MP, regardless of radiation dose or section thickness. The effects of radiation dose and section thickness on RAs of lung with attenuation coefficients lower than -960 HU (P = .007 and P < .001, respectively) and lower than -970 HU (P = .001 and P < .001, respectively) were significant. The effect of section thickness on the 1st percentile was significant (P < .001), whereas the effect of dose was not (P = .910). At CT quantification of pulmonary emphysema, the tube current-time product can be reduced to 20 mAs, but both tube current-time product and section thickness should be kept constant in follow-up examinations.

The Role of Microstructure on Ductility of Die-Cast AM50 and AM60 Magnesium Alloys

Die-cast AM50 and AM60 magnesium alloys have been examined to determine the fracture processes in bending and tension and to elucidate the influences of microstructure and porosity distribution on mechanical properties. The effect of section thickness has been explored using 2-, 6-, and 10-mm-thick die-cast plates. The processes of damage accumulation in terms of crack initiation, growth, and linkage leading to eventual failure have been studied qualitatively using progressive tensile straining experiments and three-point bend studies. The presence of a heterogeneous distribution of porosity played a critical role in the observed differences between strains to fracture in tension and in bending. More rapid damage accumulation at lower strains was observed in the high porosity regions with the rate of damage accumulation strongly dependent on the loading mode. Fracture processes at the microstructural level were characterized by scanning electron microscopy using an in-situ bending fixture. Crack initiation and growth occurred predominantly in the interdendritic eutectic regions, both in the presence of porosity and, to a lesser extent, in pore-free regions. The role of porosity volume fraction and distribution on ductility in these alloys has been examined using a modified Brown–Embury model. This model allows the prediction of fracture location in either loading mode by predicting the critical strains for the onset of cracking in differently strained regions of the test samples.

Development of a Circumferentially Throughwall Cracked Tube Specimen for Fatigue Crack Growth Rate Tests

Abstract This paper describes the development of a nonstandard specimen geometry for fatigue crack growth rate studies. Most fatigue crack growth rate data, available in open literature, for Alloy 690 and Alloy 600 were developed using standard, thick section C(T) specimens. Recently a need arose to study a circumferentially throughwall cracked tube specimen. The goal of the development was to use this tube specimen to determine any effects of section thickness or grain size on corrosion enhancement of fatigue crack growth rates in a simulated pressurized water reactor (PWR) primary side environment. Along with the final specimen geometry, the stress intensity equation and crack length monitoring equation are discussed. The stress intensity equation was converted to a standard polynomial equation in order to use a conventional automated fatigue crack growth rate software package. Symmetry arguments were made to justify the use of direct current potential drop (DCPD) and the use of the standard Johnson's equations for measuring crack lengths. Also, some discussions of the validity requirements for this geometry are presented such as stress intensity limits to remain with linear elastic fracture mechanics (LEFM) bounds and crack length limits to avoid excess bending stresses. A baseline test program was conducted on Alloy 690 tube specimens in ambient air and these results were compared with literature data. Also, a sensitivity investigation was preformed to determine the error between the polynomial equations developed and the actual equations in literature. The results of this study confirmed that a circumferentially cracked tube specimen could produce valid fatigue crack growth rate data.

Effects of section thickness on the optimum properties OF Al-8%Si alloy squeeze cast components

This study was conducted to produce squeeze castings, determine the effects of section thickness on the optimum properties of squeeze cast products from Al-Si alloy. Squeeze castings with section thickness ranging from 8 to15mm and aspect ratio (height-to-section thickness ratio) not greater than 3.125:1 were made from Al-8%Si alloy using squeeze pressures of 125MPa with the alloy poured at 700°C into a squeeze die preheated to about 250°C. A lubricant made of 10% graphite in lubricating oil was used to ease ejection of squeeze castings from the die. Squeeze time was 30s. The study found that a small deviation of ±2.0mm from the nominal size of 10.0mm has no significant impact on the optimum mechanical properties of squeeze castings. However, a large deviation of +5.0mm from the nominal size significantly reduced the optimum mechanical properties of the squeeze castings. Keywords: squeeze casting, porosity, alloy, thicknessGlobal Journal of Engineering Research Vol.4 (1&2) 2005: 13-16

Assessment of the optimum section thickness for the estimation of liver volume using magnetic resonance images: A stereological gold standard study

Estimation of liver volume using magnetic resonance (MR) images has been described previously. We have, however, not found a gold standard study, which analyzes the effect of section thickness on the estimation of liver volume. In the present study, five normal cadaveric livers were scanned in the horizontal plane using a 1.5 T MR machine (Signa 1.5T SYS#GEMSOW General Electronic, Wisconsin, USA). Consecutive sections at a thickness of 10, 7.5, 5 and 2.5 mm were used to estimate the total volume of the livers by means of the Cavalieri principle. The point counting and planimetry were used for the volume estimates. With a view to evaluating the accuracy of two techniques, all the estimations were done by the same observer. The estimated volumes concur with the actual volume of the livers obtained by the fluid displacement technique ( p > 0.05). However, the section thickness has an over- or under-projection effect on the estimated volume. The obtained volume estimation results were analyzed to reveal the deviation principles of the estimates based on the section thickness. The most suitable section thickness for the liver volume estimation was assessed to be 4–5 mm. There were no significant differences between the estimation results of two methods ( p > 0.05). The point-counting technique did, however, take less time than planimetry for estimating liver volume from MR images. Results also showed that the effect of section thickness on volume estimates using the two approaches could not be omitted and the values obtained could be calibrated using the proposed regression formula presented in this study.

Automated Detection of Pulmonary Nodules on CT Images: Effect of Section Thickness and Reconstruction Interval—Initial Results

Institutional review board approval was obtained. Informed patient consent was not required. Study was compliant with HIPAA. Performance of an automated pulmonary nodule detection program was evaluated on multi-detector row CT images that were acquired once but reconstructed retrospectively at different section thicknesses and reconstruction intervals. From raw CT data in 10 patients with pulmonary nodules, three sets of CT images were reconstructed separately in each patient by selecting two section thickness and reconstruction combinations, respectively: thin group, 1 and 1 mm; overlap group, 5 and 1 mm; and thick group, 5 and 5 mm. Nodules 3 mm in diameter and larger were detected in each group (thin group, 126 nodules; overlap group, 121 nodules; and thick group, 114 nodules) by means of consensus of two radiologists. Findings were used as the reference standard for evaluation of the computer-aided detection (CAD) program. Sensitivity and number of false-positive findings per patient by CAD were: thin group, 95.2% (120 of 126 nodules) and 5.4 findings; overlap group, 94.2% (114 of 121 nodules) and 9.7 findings; and thick group, 88.6% (101 of 114 nodules) and 23.6 findings, indicating that nodule detection degraded with increase in section thickness but improved substantially with a small reconstruction interval.

The effects of section thickness on the estimation of liver volume by the Cavalieri principle using computed tomography images

Estimation of liver volume using routine CT scans has been described previously. We have, however, not found a gold standard study which analyzes the effect of section thickness on the estimation of liver volume using CT images. In the present study, five normal livers obtained from cadavers were scanned using a Spiral CT Scanner (Xpress/GX Toshiba, Tocigi-Ken) in the horizontal plane. Consecutive sections at a thickness of 10, 5 and 1 mm were used to estimate the total volume of the livers by means of the Cavalieri principle. With a view to evaluating inter-observer differences, liver volume was estimated by three observers. The estimated volume using the classical volume estimation formula did not concur with the actual volume of the livers obtained by the fluid displacement technique. The section thickness has an over- or under-projection effect on the estimated volume. The obtained volume estimation results were, therefore, calibrated using three different approaches. The volume obtained by the calibration formulae did not differ statistically from actual liver volumes ( P < 0.05). There were also no significant differences between the performers’ estimates ( P > 0.05). Results showed that the effect of section thickness on the volume estimates could not be omitted and the obtained values could be calibrated using the proposed approaches presented in this study.

A modified PAS stain combined with immunofluorescence for quantitative analyses of glycogen in muscle sections.

Simultaneous analyses of glycogen in sections with other subcellular constituents within the same section will provide detailed information on glycogen deposition and the processes involved. To date, staining protocols for quantitative glycogen analyses together with immunofluorescence in the same section are lacking. We aimed to: (1) optimise PAS staining for combination with immunofluorescence, (2) perform quantitative glycogen analyses in tissue sections, (3) evaluate the effect of section thickness on PAS-derived data and (4) examine if semiquantitative glycogen data were convertible to genuine glycogen values. Conventional PAS was successfully modified for combined use with immunofluorescence. Transmitted light microscopic examination of glycogen was successfully followed by semiquantification of glycogen using microdensitometry. Semiquantitative data correlated perfectly with glycogen content measured biochemically in the same sample (r2=0.993, P<0.001). Using a calibration curve (r2=0.945, P<0.001) derived from a custom-made external standard with incremental glycogen content, we converted the semiquantitative data to genuine glycogen values. The converted semiquantitative data were comparable with the glycogen values assessed biochemically (P=0.786). In addition we showed that for valid comparison of glycogen content between sections, thickness should remain constant. In conclusion, the novel protocol permits the combined use of PAS with immunofluorescence and shows valid conversion of data obtained by microdensitometry to genuine glycogen data.

Coronary calcification at electron-beam CT: effect of section thickness on calcium scoring in vitro and in vivo.

To compare the accuracy of electron-beam computed tomography (CT) with 3.0- and 1.5-mm section thickness for calcium quantification and the prevalence of coronary calcifications with each. Electron-beam CT images were acquired with nonoverlapping 1.5- and 3.0-mm section thickness. Scans were obtained in an anthropomorphic thorax phantom with calcium cylinders of different sizes and densities, as well as in 1,302 study participants. A calcified lesion was defined as a minimum of 2 pixels (area, 0.52 mm2) with a minimum attenuation of 130 HU. The calcified lesions were quantified by means of a volumetric method with isotropic interpolation. From the phantom scans, mean volume scores, SDs, and measurement variations were calculated. From the participant scans, median volume scores and interquartile ranges were calculated. Participants were classified in categories based on cutoff levels for volume score quartiles for the 1.5-mm scans. An intraclass correlation coefficient (kappa value) was calculated as a measure of correlation between categories. In the phantom, deviations of calculated volumes from the true cylinder volumes and measurement variations were generally higher for the 3.0-mm protocol than for the 1.5-mm protocol. In the participants, the median volume score was 100 mm3 (interquartile range, 11-409 mm3) for the 3.0-mm protocol and 144 mm3 (interquartile range, 35-513 mm3) for the 1.5-mm protocol. Agreement between classifications of volume scores for the 1.5- and 3.0-mm scans was good (kappa = 0.62, P <.001). Compared with the quartile classification for the 1.5-mm scan, however, classifications for 370 (28%) participants were put in a different category with the 3.0-mm protocol. In a phantom, electron-beam CT scans with 3.0-mm section thickness yield less accurate estimates of calcified volume than do 1.5-mm scans. Electron-beam CT protocols with thinner sections considerably affect classification of individuals on the basis of the amount of coronary calcification depicted.

MR-derived cerebral blood volume maps: issues regarding histological validation and assessment of tumor angiogenesis.

In an effort to develop MRI methods for the evaluation of tumor angiogenesis (new blood vessel formation), MRI-derived cerebral blood volume (CBV) information has been compared to histologic measures of microvessel density (MVD). Although MVD is a standard marker of angiogenesis, it is not a direct correlate of the volume measurements made with MRI, and therefore inappropriate for the development and validation of the MR techniques. Therefore, the goal of this study was to develop an approach by which MR measurements of CBV can be directly correlated. To this end, dynamic susceptibility contrast (DSC) MRI experiments were performed in six Fisher rats implanted with 9L gliosarcoma brain tumors. Subsequently, the circulation was perfused with a latex compound (Microfil), after which 50-microm tissue sections were analyzed for vessel count, diameter, and the fraction of area comprised of vessels. The results demonstrate that while fractional area (FA) does not provide a good measure of CBV, FA corrected for section thickness effects does. Whereas the FA in normal brain was found to be 13.03 +/- 1.83% the corrected FA, or fractional volume (FV), was 1.89 +/- 0.39%, a value in agreement with those reported in the literature for normal brain. Furthermore, while no significant difference was found between normal brain and tumor FA (P = 0.55), the difference was significant for FV (P = 0.036), as would be expected. And only with FV does a correlation with the MRI-derived CBV become apparent (r(S) = 0.74). There was strong correlation (r(s) = 0.886) between the tumor / normal blood volume ratios as estimated by each technique, although the MR-ratio (1.56 +/- 0.29) underestimated the histologic-ratio (2.35 +/- 0.75). Thus, the correlation of MRI CBV methods requires a measurement of fractional vessel area and correction of this area for section thickness effects. This new independent correlative measure should enable efficient and accurate progress in the development of MRI methods to evaluate tumor angiogenesis.

3D reconstruction based on hard tissue microtome cross-section pictures in dentistry

The aim of this study was to examine the accuracy of the computerized 3D surface analyzing and volume measuring method in dentistry. Two different types of test objects were used in the first part of the measurements. Each sample of the two groups was cross-sectioned using a hard tissue microtome. The sections were photographed on both sides and were projected on a graphical tablet and analyzed using a computer program. The measured and calculated parameters were compared. In the second part, 200 μm thick horizontal sections were prepared from 11 human incisor roots using the hard tissue microtome. This way, five sections were prepared from the apical 2 mm of each root. The effects of section thickness and number were modeled by decreasing the inclusion rate of the obtained number of sections from 10 to 2 and its influence on the calculated results was determined. This method was suitable for the approximation and analysis of 3D parameters. The results indicated that using 200–300 μm section thickness, the measured values were approximately 8–21% lower than the real parameters.

CT lung densitometry: dependence of CT number histograms on sample volume and consequences for scan protocol comparability.

Our goals were to determine the dependence of CT number histograms of the lung on section thickness and reconstruction filter and to evaluate the consequences for scan protocol conformity required for universally comparable densitometry of the lungs. The effects of section thickness and reconstruction filter were parameterized with the CT's sample volume [V approximately (section thickness x in-plane resolution2)]. In a study of 31 patients, we determined as a function of V the following CT number histogram parameters: percentiles P(10) and P(90), pixel indexes PI(-905) and PI(-950), and standard deviation. Patient histogram parameters depended strongly on sample volume. Large differences were found between protocols using 1 and 10 mm sections. For small variations in somewhat larger sample volumes (> 8 mm3), discrepancies were much smaller. To obtain comparable histogram parameters, nearly identical sample volumes (> or = 8 mm3) should be used. When this condition is satisfied, available data suggest that universally comparable densitometry is feasible.

Histomorphometrical analysis of the bone-implant interface: comparison of microradiography and brightfield microscopy

Section thickness has been shown to affect the histomorphometrical measurement of bone-implant contact when analysed under brightfield microscopy. This study investigated whether microradiography of the bone-implant interface eliminated the errors associated with thick section analysis. Seven implant containing sections were utilized. Microradiographs of the thick (~100 μm) sections were taken and the sections were subsequently ground to thicknesses of 50 μm and 25 μm. Photomicrographs were taken of the microradiographs and of the sections at each thickness (100, 50 and 25 μm) under brightfield microscopy. The photomicrographs were analysed for direct bone-implant contact in the cortical passage region and along the total length of the implant. The effect of section thickness on multiple fluorochrome labelling in 10 rabbit femur specimens was also examined. Centre-to-centre interlabel distance was measured for each label pair at a thickness of 100 μm and then again after the sections were ground to 50 μm and 25 μm. The thick (100 μm) sections showed a significantly greater amount of bone-implant contact than either the thin sections or the microradiographs. There was no difference in direct bone-implant contact measured by microradiography or thin sections. However, the microradiographic analysis showed a much lower variability of the bone-implant contact than the sections evaluated under brightfield microscopy. In addition, they have the added benefit of providing information on bone mineral density. Centre-to-centre interlabel distance was not significantly different for any label pair owing to section thickness. Data from this study provides evidence that the use of microradiographs for histomorphometrical analysis of the bone-implant interface is superior to brightfield analysis of thin sections owing to the lower variability of microradiographical data and the ability to obtain bone mineral density measures. Additionally, given that interlabel distance was not significantly affected by section thickness, the use of 100 μm thick sections for analysis of fluorochrome labels in cortical bone is supported.