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PubMed2001

A semi-automatic technique for measurement of arterial wall from black blood MRI.

Black blood magnetic resonance imaging (MRI) has become a popular technique for imaging the artery wall in vivo. Its noninvasiveness and high resolution make it ideal for studying the progression of early atherosclerosis in normal volunteers or asymptomatic patients with mild disease. However, the operator variability inherent in the manual measurement of vessel wall area from MR images hinders the reliable detection of relatively small changes in the artery wall over time. In this paper we present a semi-automatic method for segmenting the inner and outer boundary of the artery wall, and evaluate its operator variability using analysis of variance (ANOVA). In our approach, a discrete dynamic contour is approximately initialized by an operator, deformed to the inner boundary, dilated, and then deformed to the outer boundary. A group of four operators performed repeated measurements on 12 images from normal human subjects using both our semiautomatic technique and a manual approach. Results from the ANOVA indicate that the inter-operator standard error of measurement (SEM) of total wall area decreased from 3.254 mm2 (manual) to 1.293 mm2 (semi-automatic), and the intra-operator SEM decreased from 3.005 mm2 to 0.958 mm2. Operator reliability coefficients increased from less than 69% to more than 91% (inter-operator) and 95% (intra-operator). The minimum detectable change in wall area improved from more than 8.32 mm2 (intra-operator, manual) to less than 3.59 mm2 (inter-operator, semi-automatic), suggesting that it is better to have multiple operators measure wall area with our semi-automatic technique than to have a single operator make repeated measurements manually. Similar improvements in wall thickness and lumen radius measurements were also recorded. Since the semi-automatic technique has effectively ruled out the effect of the operator on these measurements, it may be possible to use such techniques to expand prospective studies of atherogenesis to multiple centers so as to increase access to real patient data without sacrificing reliability.

Adult↗
PubMed2004

Automatic detection of linear artifacts in medical images.

Our purpose in this study is to describe an algorithm for the automatic detection of linear artifacts in medical images. Linear artifacts arise as a result of many different forms of tissues and tissue boundaries within the imaging volume. Additionally, linear artifacts can arise for artificial structures such as radioactive seeds and radioactive linear sources. It is the purpose of the described algorithm to automatically detect linear artifacts of a certain length and diameter. The algorithm was written and compiled on a Pentium-4 based computer in the Microsoft Visual C/C++ language. Inert coils supplied by Radiomed Inc. were implanted into a standard prostate ultrasound phantom. Transaxial ultrasound images of the implanted phantom were obtained at 2 mm increments. The coded algorithm was then applied to the ultrasound imaging volume to automatically segment out the implanted coils. Thirteen coils were implanted in the prostate phantom. Thirteen coils were automatically identified in the imaging volume. An algorithm was developed to automatically determine the position and orientation of radioactive coils within an imaging volume. The algorithm successfully identified thirteen coils implanted in an ultrasound prostate phantom.

Algorithms↗
PubMed2000

Automatic on-line electronic portal image analysis with a wavelet-based edge detector.

A fully automatic method for on-line electronic portal image analysis is proposed. The method uses multiscale edge detection with wavelets for both the field outline and the anatomical structures. An algorithm to extract and combine the information from different scales has been developed. The edges from the portal image are aligned with the edges from the reference image using chamfer matching. The reference is the first portal image of each treatment. The matching is applied first to the field and subsequently to the anatomy. The setup deviations are quantified as the displacement of the anatomical structures relative to the radiation beam boundaries. The performance of the algorithm was investigated for portal images with different contrast and noise level. The automatic analysis was used first to detect simulated displacements. Then the automatic procedure was tested on anterior-posterior and lateral portal images of a pelvic phantom. In both sets of tests the differences between the measured and the actual shifts were used to quantify the performance. Finally we applied the automatic procedure to clinical images of pelvic and lung regions. The output of the procedure was compared with the results of a manual match performed by a trained operator. The errors for the phantom tests were small: average standard deviation of 0.39 mm and 0.26 degrees and absolute mean error of 0.31 mm and 0.2 degrees were obtained. In the clinical cases average standard deviations of 1.32 mm and 0.6 degrees were found. The average absolute mean errors were 1.09 mm and 0.39 degrees. Failures were registered in 2% of the phantom tests and in 3% of the clinical cases. The algorithm execution is approximately 5 s on a 168 MHz Sun Ultra 2 workstation. The automatic analysis tool is considered to be a very useful tool for on-line setup corrections.

Automation↗
PubMed1979

Comparative study of automatic blood-gas analysers and their use in analysing arterial and capillary samples.

Three automatic blood-gas analysers were compared for ease of use; calibration; reproducibility and accuracy of results; maintenance; fault-finding; and use of expert technician time. Results obtained from arterial and capillary blood were compared with duplicate values obtained with a semi-automatic analyser controlled and calibrated with tonometered blood. No analyser was fully automatic, and all three needed maintenance by expert technicians. Difficulties were encountered when inexperienced operators used the machines. One automatic blood-gas analyser gave aberrant values for oxygen pressure (PO2) due to electrode dysfunction that was not indicated by the fault-finding system. A second analyser gave significantly lower values for blood pH than the standard machine. A comparison of pH, carbon dioxide pressure (PCO2), and PO2 measured in 40 simultaneous paired samples of arterial and arterialised capillary blood showed no significant difference for pH or PCO2, but the PO2 values were significantly lower in the capillary samples over the range studied. We conclude that all machines perform satisfactorily in terms of blood-gas analysis, but none may be regarded as fully automatic. Some degree of technical supervision is essential, as is proper training for all potential users.

Arteries↗
PubMed1995

Left atrial size and function: assessment using echocardiographic automatic boundary detection.

OBJECTIVE: To evaluate the waveforms of left atrial area changes obtained by automated boundary detection with newly developed acoustic quantification technology. DESIGN: All subjects had measurements of left atrial areas taken in the apical four chamber, parasternal long axis, and parasternal short axis views using both conventional echocardiographic methods and automatic boundary detection on two occasions separated by at least a week. On the second visit measurements were also repeated in healthy volunteers after acute intravenous volume loading with 1 litre of saline over 2-5 minutes. SETTING: A university medical school echocardiographic laboratory. SUBJECTS: 12 healthy male volunteers and 8 patients with cardiac disease (5 with congestive heart failure, 1 with mitral stenosis, and 2 with hypertensive left ventricular hypertrophy, and dilated left atria). RESULTS: There was close correlation between conventionally derived left atrial areas and those obtained by automatic boundary detection, particularly in the apical four chamber view (r = 0.98). Both inter and intra observer variabilities (coefficient of variation) for left atrial areas measured by automatic boundary detection were good (4.7-14.2% and 8.1-18.6% respectively). The reproducibility (coefficient of variation) for derived indices of left atrial function, however, was much poorer (10.4-104.8% and 12.5-88% respectively). After acute volume loading significant increases in left atrial area were observed at all stages in the cardiac cycle. CONCLUSIONS: These data demonstrate that although the reproducibility of left atrial functional indices is poor, instantaneous left atrial cavity measurements with automatic boundary detection are reproducible. This suggests that automatic boundary detection may assist in serial non-invasive measurement of left atrial size to assess disease states and treatments.

Adult↗
PubMed1997

Automatic nasal continuous positive airway pressure titration in the laboratory: patient outcomes.

BACKGROUND: Manual titration of nasal continuous positive airway pressure (NCPAP) treatment for obstructive sleep apnoea (OSA) is time consuming and expensive. There are now "intelligent" NCPAP machines that try to find the ideal pressure for a patient by monitoring a combination of apnoeas, hypopnoeas, inspiratory flow limitation, and snoring. Although these machines usually find similar pressures to skilled technicians, it is not clear if their use in the sleep laboratory influences subsequent acceptance by patients. This study addresses this question. METHODS: One hundred and twenty two patients undergoing a trial of NCPAP were randomly allocated to either manual or automatic (Horizon, DeVilbiss) titration of pressure during their first night on NCPAP in a hospital sleep laboratory. The primary outcome (available on 112 patients) was the acceptance of NCPAP or otherwise six weeks following the initial titration night. Baseline indicators of severity were compared between the groups, as were the pressures selected and the subsequent improvement in the sleepiness of the patients. RESULTS: The initial severity of OSA was not significantly different in the two groups and the mean (SD) NCPAP pressures were similar (manual 8.7 (2.5) cm H2O, automatic 8.2 (2.1) cm H2O). The percentage of patients successfully established on CPAP at six weeks was 64% and 73% for the manual and automatic groups, respectively; 13% and 2%, respectively, in the manual and automatic groups had given up completely (p < 0.05), and there were about equal numbers (23% versus 25%) in the two groups who were still undecided. CONCLUSIONS: The substitution of automatic NCPAP titration for manual titration during the first night of NCPAP in patients with OSA does not reduce the number accepting the treatment at six weeks and may slightly improve it. This has important cost saving potential.

Humans↗
PubMed2002

Cerebellar damage impairs automaticity of a recently practiced movement.

It has been suggested that the cerebellum plays a critical role in learning to make movements more "automatic" (i.e., requiring less attention to the details of a movement). We hypothesized that cerebellar damage compromises learning of movement automaticity, resulting in increased attentional demands for movement control. The purpose of our study was to determine whether cerebellar damage disrupts the ability to make a practiced movement more automatic. We developed a dual task paradigm using two tasks that did not have overlapping sensory or motor requirements for execution. Our motor task required subjects to maintain an upright posture while performing a figure-8 movement using their arm. This motor task was chosen to simulate requirements of everyday movements (e.g., standing while reaching for objects), but it was novel enough to require practice for improvement. Our secondary task was an auditory vigilance task where subjects listened to letter sequences and were asked to identify the number of times a target letter was heard. We tested controls and people with cerebellar damage as they practiced the movement task alone and then performed it with the auditory task. We recorded 3D position data from the arm, trunk, and leg during the movement task. Errors were recorded for both the movement and the letter tasks. Our results show that cerebellar subjects can improve the movement to a very limited extent with practice. Unlike controls, the motor performance of cerebellar subjects deteriorates to prepractice levels when attention is focused away from the movement during dual task trials. Control subjects' insensitivity to dual task interference after practice was due to learned movement automaticity and was not a reflection of better dual task performance generally. Overall, our findings suggest that the cerebellum may be important for shifting movement performance from an attentionally demanding (unpracticed) state to a more automatic (practiced) state.

Adult↗
PubMed1999

Automatic morphological sieving: comparison between different methods, application to DNA ploidy measurements.

The aim of the present study is to propose alternative automatic methods to time consuming interactive sorting of elements for DNA ploidy measurements. One archival brain tumour and two archival breast carcinoma were studied, corresponding to 7120 elements (3764 nuclei, 3356 debris and aggregates). Three automatic classification methods were tested to eliminate debris and aggregates from DNA ploidy measurements (mathematical morphology (MM), multiparametric analysis (MA) and neural network (NN)). Performances were evaluated by reference to interactive sorting. The results obtained for the three methods concerning the percentage of debris and aggregates automatically removed reach 63, 75 and 85% for MM, MA and NN methods, respectively, with false positive rates of 6, 21 and 25%. Information about DNA ploidy abnormalities were globally preserved after automatic elimination of debris and aggregates by MM and MA methods as opposed to NN method, showing that automatic classification methods can offer alternatives to tedious interactive elimination of debris and aggregates, for DNA ploidy measurements of archival tumours.

Aneuploidy↗
PubMedDate not supplied

[Automatization of a hospital-based tumor registry].

INTRODUCTION: To increase data reliability and reduce the costs associated with the HTR, the Catalan Institute of Oncology programmed the manual procedures of data collection from databases by means of a computer application (ASEDAT). MATERIAL AND METHOD: ASEDAT detects the incident tumors of the registry from the databases of the pathology records (PR) and discharge records (DR) and selects the basic information from both databases. Data from the HTR data was collected for the period 1999-2000 by means of 2 procedures: manual and automatized collection and the results obtained were compared. RESULTS: 10,498 cancer patients were detected. Manual resolution detected 8,309 incident tumors and 2,374 prevalent tumors. ASEDAT automatically detected 8,901 patients (84.8%), in whom 8,367 incident tumors were detected (58 more tumors than the manual procedure). Validation of agreement was performed in the incident tumors detected by both methods (7,063 tumors). In 6,185 tumors (87.6%) the information agreed in all the variables. Of the discordant tumors, 692 (9.8%) were obtained by the RHT staff using manual resolution, and the remainder (186; 2.6%) were obtained by the application (automatic resolution). CONCLUSIONS: Cancer registry automatization is feasible when PR and DR databases are available, coded and automatized.

Hospital Records↗
PubMed1986

Comparison of visual analysis and automatic sleep stage scoring (Oxford Medilog 9000 System).

The Oxford Medilog 9000 System with Sleep Stager, a device for the mobile recording of sleep EEGs and automatic analyses of sleep, was tested with regard to its functional capacity, possible applications and reliability. Four all-night sleep records were evaluated visually and compared with the automatic analysis. Tendentially uniform differences were evident in two areas: the automatically scored sleep onset time was always shorter than the visually assessed time, and the automatic analysis consistently scored less REM than the visual assessment. There ought, therefore, to be fundamental reasons for these two situations. The advantages of the mobile EEG recording and automatic analysis of sleep are that considerably less time and personnel are involved, and that the results are readily available, which means that one can perform considerably more investigations. The differences from the visual evaluation can be attributed to the system and are thus calculable, provided that a few necessary improvements are made with regard to reliability.

Ambulatory Care↗
PubMed1991

Abnormal automatic rhythms in ischemic Purkinje fibers are modulated by a specific alpha 1-adrenergic receptor subtype.

BACKGROUND: Recent advances in adrenergic pharmacology have made possible the identification of alpha 1-adrenergic receptor subtypes using the specific blockers chloroethylclonidine and WB 4101. METHODS AND RESULTS: In the present study, we used these two blockers to determine the mechanisms responsible for automatic rhythms occurring during simulated ischemia and reperfusion of isolated canine Purkinje fibers. Experiments were done in the presence of propranolol to minimize beta-adrenergic contributions to the rhythms studied. In the control situation, all fibers showed membrane potentials greater than -90 mV and normal automatic rhythms. During simulated ischemia, membrane potential depolarized to the -60 mV range. Abnormal automaticity was seen in 20% of fibers not treated with phenylephrine and in 50% of those superfused with 1 x 10(-7) M phenylephrine. The incidence of abnormal automaticity was reduced to 0% by WB 4101 (which blocks phosphoinositide metabolic effects of alpha 1-adrenergic stimulation in the heart) and was increased to 90% by chloroethylclonidine (which blocks Na-K pump-stimulating effects of alpha-agonists). Moreover, the ischemic fibers were significantly more hyperpolarized during superfusion with WB 4101 than with chloroethylclonidine. Triggered activity induced by delayed or early after depolarizations was not seen in any experiment. CONCLUSIONS: Automatic arrhythmias induced by alpha 1-adrenergic stimulation during simulated ischemia may be attributed to a specific alpha 1-adrenergic receptor subtype that is blocked by WB 4101. These results have important implications with respect to the induction of arrhythmias in the setting of ischemia and the means for their prevention or treatment.

Adrenergic alpha-Antagonists↗
PubMed2002

Automatic online embolus detection and artifact rejection with the first multifrequency transcranial Doppler.

BACKGROUND AND PURPOSE: The goal of this study was to assess the first multifrequency transcranial Doppler system specially developed for online automatic detection of cerebral microemboli. METHODS: The multifrequency Doppler instrumentation insonates simultaneously with 2.0- and 2.5-MHz frequencies. The detection threshold for embolus detection used in this study was a relative Doppler energy increase of >20 dB. ms, at which point the Doppler power increase was at least 5 dB and lasted >4 ms above the background energy. Four parameters were used in an optimized binary decision tree to recognize emboli: quarter Doppler shift, maximum duration limit, reference gate, and bidirectional enhancement. In in vitro studies, 200 plastic microspheres (80 micro m), 200 gas bubbles (8 to 25 micro m), and 600 artifacts were studied in a pulsatile closed-loop system. In vivo studies were carried out for 1 hour in 15 patients with mechanical heart valves and in 45 patients with carotid stenosis. This gave a total of 60 hours of online automatic monitoring in patients. RESULTS: All 400 plastic spheres and microbubbles were automatically detected and correctly classified. Of the 600 artifacts, 596 (99.3%) were correctly classified as artifacts, and 4 (0.7%) were incorrectly identified as emboli (kappa=0.992, P<0.001). The experienced observer detected a total of 554 emboli and 800 artifacts in the heart valve (521 emboli, 400 artifacts) and carotid stenosis (33 emboli, 400 artifacts) patients. With multifrequency Doppler, 546 of these emboli (98.6%) and 791 of these artifacts (98.9%) were automatically detected and correctly classified as embolus or artifact (kappa=0.953, P<0.0001). CONCLUSIONS: We found that multifrequency transcranial Doppler had a relatively high sensitivity and specificity when used to automatically detect cerebral microemboli and reject artifacts online.

Artifacts↗
PubMedDate not supplied

Validation of a new method of detecting peripheral artery disease by determination of ankle-brachial index using an automatic blood pressure device.

Peripheral artery disease (PAD) is a predictor of total and cardiovascular mortality; its most valuable simple index is the ankle-brachial index (ABI). The present study was designed to assess whether a commercially available automatic device could be used to determine ABI in comparison with the classical Doppler method. The ABI was defined as the ratio of systolic blood pressure at each ankle to the maximal brachial systolic pressure, a pathological index being defined for a ratio <0.90. The ABI were calculated in 219 consecutive patients (aged 55 +/-19 years) with systolic blood pressure measured either by using a mercury sphygmo-manometer and a continuous-wave Doppler probe or an automatic manometer Omron M4. This device has been validated for measurements in upper limbs, and so the authors undertook validation in the lower limbs versus intraarterial measurements. There was an excellent correlation between intraarterial measurements and automatic readings in the range of 70-220 mm Hg, r=0.99, p<0.001. The systolic pressures measured in upper limbs correlated well in the right (r=0.87, p<0.001) and the left (r=0.89, p<0.001) upper limbs; and in the left (r=0.72, p<0.001) and the right (r=0.68, p<0.001) lower limbs. Correlations between ABI in both methods were good in the left (r=0.66, p<0.001) and the right (r=0.61, p<0.001) lower limbs. The sensitivity (76%), specificity (95%), positive predictive value (86%), negative predictive value (90%), and global accuracy (89%) of a pathological automatic index to predict an abnormal Doppler index were good. The use of a simple, automatic blood pressure device to determine ABI appears feasible, easy, and precise. It would provide a practical tool for physicians not trained in Doppler to detect PAD.

Adult↗
PubMedDate not supplied

Can prosody aid the automatic classification of dialog acts in conversational speech?

Identifying whether an utterance is a statement, question, greeting, and so forth is integral to effective automatic understanding of natural dialog. Little is known, however, about how such dialog acts (DAs) can be automatically classified in truly natural conversation. This study asks whether current approaches, which use mainly word information, could be improved by adding prosodic information. The study is based on more than 1000 conversations from the Switchboard corpus. DAs were hand-annotated, and prosodic features (duration, pause, F0, energy, and speaking rate) were automatically extracted for each DA. In training, decision trees based on these features were inferred; trees were then applied to unseen test data to evaluate performance. Performance was evaluated for prosody models alone, and after combining the prosody models with word information--either from true words or from the output of an automatic speech recognizer. For an overall classification task, as well as three subtasks, prosody made significant contributions to classification. Feature-specific analyses further revealed that although canonical features (such as F0 for questions) were important, less obvious features could compensate if canonical features were removed. Finally, in each task, integrating the prosodic model with a DA-specific statistical language model improved performance over that of the language model alone, especially for the case of recognized words. Results suggest that DAs are redundantly marked in natural conversation, and that a variety of automatically extractable prosodic features could aid dialog processing in speech applications.

Decision Trees↗
PubMedDate not supplied

Automatic resolution of ambiguous terms based on machine learning and conceptual relations in the UMLS.

UNLABELLED: Motivation. The UMLS has been used in natural language processing applications such as information retrieval and information extraction systems. The mapping of free-text to UMLS concepts is important for these applications. To improve the mapping, we need a method to disambiguate terms that possess multiple UMLS concepts. In the general English domain, machine-learning techniques have been applied to sense-tagged corpora, in which senses (or concepts) of ambiguous terms have been annotated (mostly manually). Sense disambiguation classifiers are then derived to determine senses (or concepts) of those ambiguous terms automatically. However, manual annotation of a corpus is an expensive task. We propose an automatic method that constructs sense-tagged corpora for ambiguous terms in the UMLS using MEDLINE abstracts. METHODS: For a term W that represents multiple UMLS concepts, a collection of MEDLINE abstracts that contain W is extracted. For each abstract in the collection, occurrences of concepts that have relations with W as defined in the UMLS are automatically identified. A sense-tagged corpus, in which senses of W are annotated, is then derived based on those identified concepts. The method was evaluated on a set of 35 frequently occurring ambiguous biomedical abbreviations using a gold standard set that was automatically derived. The quality of the derived sense-tagged corpus was measured using precision and recall. RESULTS: The derived sense-tagged corpus had an overall precision of 92.9% and an overall recall of 47.4%. After removing rare senses and ignoring abbreviations with closely related senses, the overall precision was 96.8% and the overall recall was 50.6%. CONCLUSIONS: UMLS conceptual relations and MEDLINE abstracts can be used to automatically acquire knowledge needed for resolving ambiguity when mapping free-text to UMLS concepts.

Abbreviations as Topic↗
PubMed2001

A new image analysis system for biological dosimetry by fluorescent in situ hybridization. Step 1: metaphase finder and automatic metaphase acquisition validation.

Because of the large number of cells to be analyzed in cases of overexposure to ionizing radiation, an automated imaging system is desirable for scoring both translocations and dicentrics. This system should include three essential steps: automatic metaphase finding, automatic image capture at high magnification, and, finally, optimized data analysis for aberration interpretation. We evaluated a new image analysis system (CYTOGEN, IMSTAR, France) and found that its metaphase finder saved time, as much as quadrupling the speed of scoring chromosomal aberrations. Automatic metaphase selection did not appear to induce bias. We confirmed the equivalence of observing aberrations on a screen after automatic image capture and direct observation under a microscope. This work validated all of the steps necessary for obtaining images for automatic chromosomal aberration detection. The protocols for the detection of translocations may now be applied for biological dosimetry. This step will be validated in a future study.

Image Processing, Computer-Assisted↗
PubMed1978

Ventricular reentry and automaticity in myocardial infarction. Effect of size of injury.

The effects of the size of acute myocardial infarction on ventricular reentry and automaticity were studied in 36 mongrel dogs. Large transmural myocardial infarctions were produced by ligation of the left anterior descending coronary artery (major ligation; diameter of infarction above 4.0 cm), and small subendocardial or intramural infarctions were produced by ligating a small diagonal branch of the left anterior descending coronary artery (minor ligation; diameter of infarction less than 1.5 cm). Reentrant arrhythmias were induced by rapid ventricular stimulation, and ventricular automaticity was determined during vagal stimulation. Ventricular automaticity became enhanced only 30 to 45 minutes after both major and minor coronary arterial ligations; however, the animals with major ligations attained a higher level of increased automaticity. While automaticity became enhanced in both groups reentrant arrhythmias could never be produced artificially (or observed spontaneously) in the animals with myocardial infarctions. The dependence of the so-called reentrant arrhythmias on the size of the infarction is a major support for the theory of reentry as the basis for these arrhythmias.

Animals↗
PubMed1995

Removal of interproximal subgingival plaque by hand and automatic toothbrushes.

Subgingival plaque removal at interproximal sites by automatic and hand toothbrushes was compared with control sites at which cleansing was not performed. There were 58 patients, 35 to 63 years of age, each with one hopeless tooth requiring extraction. Each patient was randomly assigned to one of four test groups: hand brush; automatic toothbrush 1; automatic toothbrush 2; and no brushing. The brushing instructions as stated by the manufacturers were demonstrated and the patient brushed the sextant containing the test tooth for 20 seconds. The level of the gingival margin was marked at each interproximal test site. The teeth were extracted and processed for SEM, and subgingival plaque was viewed at X100 and X2000 magnifications. A montage of photomicrographs of the gingival groove to the occlusal margin of the bacterial plaque at X100 magnification was made and the distance from the groove to the margin was measured. An ANOVA was performed using P = 0.05 level for significance. Due to processing difficulties, only 33 specimens were available for analysis. The average distances from the groove to the subgingival plaque front for the four test groups were 0.514, 0.132, 0.163, and 0.111 mm respectively. The maximum distance (1.5 mm) of plaque removal was greatest for the hand toothbrush. Due to the large standard deviation (0.636 compared to 0.146, 0.250, and 0.124 respectively), the hand brushing group was excluded from ANOVA. There were no statistically significant differences among the automatic toothbrushes and the no brushing control (P = 0.8393). It was concluded that a single session of oral hygiene instruction with an automatic toothbrush did not result in subgingival interproximal plaque cleansing.

Adult↗