Titanium corrosion products from dental implants and their effect on cells and cytokine release: A review

INTRODUCTION

Titanium is considered to be an inert material owing to the ability of the material to form a passive titanium oxide layer. However, once the titanium oxide layer is lost, it can lead to exposure of the underlying titanium substructure and can undergo corrosion.

SUMMARY

The article explores the role of titanium ions and particles from dental implants on cells, cytokine release, and on the systemic redistribution of these particles as well as theories proposed to elucidate the effects of these particles on peri-implant inflammation based on evidence from in-vitro, human, and animal studies. Titanium particles and ions have a pro-inflammatory and cytotoxic effect on cells and promote the release of pro-inflammatory mediators like cytokines. Three theories to explain etiopathogenesis have been proposed, one based on microbial dysbiosis, the second based on titanium particles and ions and the third based on a synergistic effect between microbiome and titanium particles on the host.

CONCLUSION

There is clear evidence from in-vitro and limited human and animal studies that titanium particles released from dental implants have a detrimental effect on cells directly and through the release of pro-inflammatory cytokines. Future clinical and translational studies are required to clarify the role of titanium particles and ions in peri-implant inflammation and the etiopathogenesis of peri-implantitis.

Association of F. alocis and D. pneumosintes with Periodontitis Disease Severity and Red Complex Bacteria

Oral biofilms are considered the principal etiological agent in the development of periodontitis. Novel species that may contribute to periodontitis and dysbiosis have been identified recently. The study aims to evaluate the presence of F. alocis and D. pneumosintes in healthy and diseased patients and their association with clinical parameters and with red complex bacteria. The study included 60 subjects, with 30 patients each in the healthy and periodontitis groups. The clinical parameters were noted, and samples were subjected to DNA extraction followed by a polymerase chain reaction. Statistical analysis was performed using the Graph Pad Prism software. Results: F. alocis and D. pneumosintes were detected at a significantly higher percentage in the periodontitis group compared to the healthy group (p < 0.05). D. pneumosintes was significantly associated with T. forsythia in the periodontitis group (p < 0.05). Both of these organisms were present in sites with higher clinical attachment loss (p < 0.05). This study demonstrated that both F. alocis and D. pneumosintes were detected at a significantly higher percentage in periodontitis subjects and were detected more frequently in sites with a greater clinical attachment loss. It was also evident that both F. alocis and D. pneumosintes can be present independently of other putative periodontal pathogens.

Association of adipokine levels with obesity in periodontal health and disease: A systematic review with meta-analysis and meta-regression

This study aimed to investigate the levels of serum, gingival crevicular fluid (GCF), and salivary adipokines and their possible relationship with periodontitis and obesity. An electronic search was conducted in the following databases: PubMed/ Medline, Scopus, and EBSCOhost through February 2023. Two independent reviewers screened the titles, abstracts, and full text of all the studies. Studies comparing the levels of adipokines in GCF, serum, and/or saliva in subjects with obesity and periodontitis (group 1), subjects with normal weight and periodontitis (group 2), and subjects with obesity and gingival health (group 3) were included. Meta-analyses and meta-regression were performed on the data from included studies. Seventeen studies with study participants ranging from 30 to 120 were included with subjects in each group ranging from 10 to 40. There was a significant increase in levels of serum TNF-α, leptin, IL-6, and CRP between groups 1 and 2 (p < .05). In GCF, TNF-α and resistin levels were significantly higher (p < .05) in Group 1 vs. 2. Serum level of leptin was higher for group 1 vs. 3 (p < .05). Meta-regression analysis revealed that the obesity definition (body mass index (BMI) cut-off value >25 or >30) was significant for serum resistin (p < .05) and GCF resistin (p < .05) between group 1 and 2. The current analysis indicates that both periodontitis and obesity can modulate the pro-inflammatory cytokines at systemic and local levels. This bidirectional interaction of periodontitis and obesity via the inflammation pathway seems likely plausible. Further studies are required to elucidate this mechanism in more detail.

Bibliometric Analysis of Dental Implantology Journals from 1991-2023

Dental implants are an established treatment options for varying edentulous conditions and has grown in popularity since the 1990's. This increased clinical application has evidenced a parallel increase in dental implant related research. The objective of this paper was to perform a comprehensive bibliometric analysis of five dental implantology journals from 1991-2023.

MATERIALS AND METHODS

We performed a search in the ISI Web of Science database between 1991 and 2023 in 5 journals with a focus on dental implantology: Clinical Oral Implant Research, Clinical Implant Dentistry and Related Research, Implant Dentistry, International Journal of Oral and Maxillofacial Implants, and International Journal of Oral Implantology. Results marked as correction, retraction notices, retracted articles, meeting abstract, withdrawn publications were removed from the analysis. The time period analyzed was divided into 4 decades: 1991-2000, 2001-2010, 2011-2020, 2021-2023. Additionally, the top 100 cited papers were also exported separately. Authors and countries with most publications were tabulated from the Web of Science database. VOS Viewer software was used to create network maps of keywords and title word occurrences for each of the time periods. Histcite software was used to analyze number of publications and citation counts.

RESULTS

Network maps of keywords and title word occurrences suggested an early focus on osseointegration and titanium implants between 1991-2000. Publications between 2001-2010 saw a focus on in-vivo studies, implant surface and peri-implantitis. Publications post 2011 saw a focus on bone regeneration, complications and zygomatic implants. USA ranked highest in total number of publications in all time periods analyzed.

CONCLUSIONS

Within the limitations of the study, we reported a comprehensive bibliometric analysis from 1990-2023. We identified trends in keywords and titles of dental implant publications in these journals which mirrored the trends seen in clinical practice.

Quantitative Evaluation of Porphyromonas gingivalis in Indian Subjects With Chronic Periodontitis by Real-Time Polymerase Chain Reaction

Background and Aims:

Porphyromonas gingivalis ( P. gingivalis) is considered as an important pathogen responsible for periodontal disease which is characterized by inflammation of gingiva and destruction of periodontal ligament and alveolar bone leading to loss of tooth. Along with clinical investigations, suitable microbiological analysis needs to be performed which could provide more insight into the disease severity. We aim to quantify P. gingivalis by real-time PCR (RT-PCR) and analyze its association with demographic data including clinical parameters.

Materials and Methods:

The study consisted of chronic periodontitis patients (CP group) and healthy subjects (H group) with 120 samples in each group. RT-PCR was carried out by the SYBR Green assay to target 16S ribosomal ribonucleic acid species-specific region of P. gingivalis. Standard strain of P. gingivalis ATCC 33277 was used as a control.

Results:

In the CP group, 79.16% samples were found positive for P. gingivalis, whereas 29.17% samples were positive in the H group. A significant difference was found when the prevalence was compared within males and females ( P < .001 for both). In the older age groups, we found a higher rate of detection of P. gingivalis. As analyzed by Spearman’s correlation test, the number of cells of P. gingivalis was significantly associated with probing depth ( P = .02) and clinical attachment level ( P = .01) in the CP group. The mean cell number of P. gingivalis was found to be increasing with increasing levels of probing depth and clinical attachment level ( P < .001 and P = .01, respectively).

Conclusion:

The present study reaffirms that the P. gingivalis microbe is significantly associated with the chronic periodontitis and that its level varies with the severity of the disease. Colonization of the bacterium is significantly associated with severe forms of the disease.

Simplified Method of Detection of Dialister invisus and Olsenella uli in Oral Cavity Samples by Polymerase Chain Reaction

Aims and Objectives:

The oral microbial flora is highly complex and diverse with obligate anaerobic bacteria as the predominant component. Most of these are not yet cultivated/difficult to cultivate due to technical limitations. In this study, we aim to detect two novel oral bacterial species Dialister invisus and Olsenella uli by simplified and economical procedure of polymerase chain reaction (PCR) and study their association with primary and persistent endodontic infections.

Material and Methods:

The study involved 60 patients that included 30 patients of primary endodontic infections and 30 with persistent endodontic infections. The sample collection from the root canal was performed by universally accepted protocol by using sterile paper points. The deoxyribonucleic acid (DNA) extraction was done, followed by PCR with species specific primers. We made several changes to the protocol mentioned by original authors. We adopted a one-step protocol for amplification of bacterial DNA, omitting the 16SrDNA amplification step with universal primers.

Results:

It was seen that 7 (23.3 %) samples in primary endodontic infection group and 24 (80 %) samples in persistent endodontic infection group were positive for D. invisus. On the other hand, 11 (36.6 %) patients of primary endodontic infection showed positivity for O. uli in comparison to 9 (30 %) of persistent endodontic infection.

Conclusion:

The results from the present study showed efficient amplification of both O. uli and D. invisus in a single-step PCR. Hence, we conclude that the modified protocol used here with taq polymerase enzyme offers a faster and cheaper alternative to nested PCR without compromising the quality of amplification process.

Characterization and serotype distribution of Aggregatibacter actinomycetemcomitans: Relationship of serotypes to herpesvirus and periodontal status in Indian subjects

BACKGROUND

The virulence of Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans) in any individual depends on the type of strain of this bacterium. To our knowledge, there have been no studies reported in Indian subjects about A. actinomycetemcomitans serotype occurrence, co-existence with herpes virus and the possible influence of such co-existence on periodontal pathology.

METHODS

Subjects for this study were a subset of a larger study to identify the prevalence of A. actinomycetemcomitans in chronic periodontitis. A total of 63 subjects (12 periodontally healthy and 51 with chronic periodontitis) who were positive for A. actinomycetemcomitans were serotyped for strain-level identification. The presence of Human Cytomegalovirus (CMV) and Epstein-Barr virus (EBV) was tested in subgingival plaque samples by polymerase chain reaction.

RESULTS

All five serotypes a to e were detected. Of the samples analyzed 38.09% harbored a single serotype, 36.5% had two serotypes, 6.3% demonstrated three and 4.7% demonstrated four serotypes. None of the samples showed presence of JP2 strain. Serotypes b, c, and e were most frequently identified in these individuals (46.03%, 36.5% and 38.09% respectively). Presence of serotypes b and c and absence of serotype d was associated with increased PD and CAL. Among 63 samples analyzed, 11 samples had CMV, four samples had EBV and nine samples had both these viruses. The PD and CAL were significantly higher (p = 0.04) when a combination of CMV and one of the serotypes was present indicating a pathological role of the coexistence.

CONCLUSION

Multiple serotypes are associated with chronic periodontitis in Indians, however, JP2 strains are not detectable in this cohort. Presence of multiple serotypes and a combination of any serotype with herpesvirus is associated with greater severity of the disease.

The detection of eight putative periodontal pathogens in adult and rapidly progressive periodontitis patients: an institutional study

PURPOSE

Periodontal disease is a commonly prevalent problem faced alike by both the developed and third world countries but showing wide variations in prevalence and severity across different geographical areas. The purpose was to identify Actinobacillus actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi), Ekinella corrodens (Ec), Campylobacter rectus (Cr), Bacteroides forsythus (Bf), Treponema denticola (Td) and Fusobacterium nucleatum (Fn) in Indian adult periodontitis and rapidly progressive periodontitis patients.

MATERIALS AND METHODS

Paper points were used to collect the sample from 28 sites in both adult periodontitis and rapidly progressive periodontitis (8 healthy/20 diseased sites) patients and DNA analysis done. The categorical data was analysed by Fishers exact test and difference in the clinical parameters was tested by Mann-Whitney test.

RESULTS

In healthy sites of adult and rapidly progressive periodontitis patients, Aa, Ec, Bf and Aa, Pg, Pi, Td, Fn were detected respectively. However, when diseased and healthy sites were compared in both adult periodontitis and rapidly progressive periodontitis patients respectively, only Pg( P =0.004), Cr( P =0.04), Fn( P =0.014) and Pg( P =0.002), Cr( P =0.02), Fn( P =0.008) were statistically significant.

CONCLUSION

The prevalence of the microorganisms correlate with the clinical parameters like probing depth and bleeding on probing as seen in the Japanese and Western periodontitis patients' population.

Internal iliac artery ligation for arresting postpartum haemorrhage

OBJECTIVE

To study the role of internal iliac artery ligation (IIAL) in arresting and preventing postpartum haemorrhage (PPH).

DESIGN

Retrospective chart review of women undergoing therapeutic IIAL for PPH or prophylactic IIAL for risk of PPH.

SETTING

Tertiary care hospital in Pune, India.

SAMPLE

Women admitted to King Edward Memorial (KEM) Hospital, Pune, India, who underwent IIAL to control or prevent PPH.

METHODS

Bilateral IIAL was performed in all women.

MAIN OUTCOME MEASURES

Need for re-laparotomy or hysterectomy to control haemorrhage, complications of the procedure.

RESULTS

Out of 110 women who underwent IIAL, 88 had therapeutic IIAL for PPH from atony (36), genital tract injury (23), placenta praevia (21), placental abruption (4), uterine inversion (3) or coagulopathy (1). Hysterectomy was performed after IIAL failed to arrest haemorrhage in 33 (39.3%) of 84 women (excluding 4 with vaginal lacerations). Hysterectomy was more likely with uterine rupture (79%) than with nontraumatic PPH (up to 27%). Failure to control haemorrhage by IIAL was evident immediately, and bleeding arrested by IIAL did not recur to require later laparotomy in any woman. Out of 22 women at high risk for PPH undergoing prophylactic IIAL at caesarean section, none had subsequent haemorrhage. One woman had an iliac vein injury that was repaired with no further morbidity. There were no ischaemic complications either during inpatient stay or up to 6 weeks.

CONCLUSIONS

IIAL is useful in the treatment and prevention of PPH from any cause. Early resort to IIAL effectively prevents hysterectomy in women with atonic PPH. In traumatic PPH, IIAL facilitates hysterectomy or repair as indicated and prevents reactionary haemorrhage.

A non-parametric statistical analysis in the measurement of outdoor gamma exposure to the residents around Trombay

During this study, non-parametric statistical methods were used to validate the measured gamma dose rate with the calculated one, around Trombay. Portable dose rate digital gamma spectrometry system (target fieldSPEC) was used for in situ measurement of external gamma (gamma) dose rate (measured) with the range of 1 nSv/h-10 Sv/h. The activity concentration of U-238, Th-232, K-40 and Cs-137 in the soil and their respective external dose-conversion factor (nSv/h/Bq/kg) was used to evaluate the gamma dose rate (calculated). Non-parametric statistical tool like Box- and -Whisker Plot, Spearman's (rho) rank Correlation coefficient, the Wilcoxon/Mann-Whitney test and chi(2) distribution test have been applied for validation. The randomness or discrete behaviour of measured and calculated dose rate was obvious from the Box- and -Whisker Plot as mean and median of the two are not equal. The inter quartile range (Q3-Q1), which explains about the dispersion of measured and calculated dose rate were also evaluated and found to be 10 and 16 microSv/y, respectively. The linear association between the order of ranks of the two dose rates was established by using Spearman's (rho) rank correlation that showed a coefficient of R = +0.90 with the intercept +1.9, whereas Pearson's correlation was observed with a coefficient of R = +0.93 with the intercept -25.6. Wilcoxon/Mann-Whitney test shows that, medians of the calculated and the measured dose rate as significantly different under the assumption of null hypothesis and measured dose rate was made to the normal distribution by applying Z-statistics. Value of chi(2) was calculated and found to be 284.95, which was very much greater than the critical value of chi(2)(0.05) = 43.77 at a degree of freedom 30, concluding that there is a highly significant difference between the measured and calculated dose rate at 5% significance level.

DNA probe analysis in smoker and non smoker rapidly progressive periodontitis patients--a pilot study

Smoking is one of the most significant risk factors in the development and further advancement of inflammatory periodontal disease. The bacteria A. actinomycetemcomitans, P. gingivalis and P. intermedius as indicated as the potential pathogens associated with periodontal disease. Since the bacteria mentioned as well as smoking are factors associated with periodontitis it is of importance to elucidate the interrelationship between these factors. The purpose of this study was to investigate the prevalence of A. actinomycetemcomitans, P. gingivalis and P. intermedius in subgingival plaque samples obtained form healthy and diseased sites of patients with rapidly progressive periodontitis who were smokers and non smokers along with other clinical parameters.

Cervical nodal metastases in squamous cell carcinoma of the head and neck: what to expect

The treatment and management of malignancies of the head and neck is directly altered by the presence of metastatic cervical adenopathy. The treatment of nodal metastases in squamous cell carcinoma of the head and neck (HNSCCA) is determined by the lymphatic drainage of the upper aerodigestive tract. The lymphatic drainage is site-specific and occurs in a predictable manner. The purpose of this text is to provide an overview of the normal routes of lymphatic drainage in the head and neck and correlate this with the current nodal classification system. The specific aims of this manuscript are to 1) illustrate the expected lymphatic drainage patterns of HNSCCA arising in the different subsites (nasopharynx, oropharynx, oral cavity, larynx, and hypopharynx) and 2) review the expected frequency of metastases within nodal groups for HNSCCA that arise in these locations. An understanding of the topographical distribution and incidence of cervical lymph node metastases plays an integral role in the physical examination and radiological evaluation of patients with HNSCCA. For the neuroradiologist, this information may increases the ability to identify those nodal groups at risk for metastatic involvement.

Intercostal lung herniation--depiction on spiral CT

Computed tomography (CT) is the imaging modality of choice for the demonstration of intercostal lung herniation. The use of forced expiration and Valsalva's manouevre during CT scanning has been recommended in selected cases. We report a case of intercostal lung herniation, demonstrated only on coughing on spiral CT.

Inflammatory myofibroblastic tumor involving the pterygopalatine fossa

SUMMARY

Inflammatory myofibroblastic tumors (IMT) comprise a rare group of lesions characterized histologically by acute and chronic inflammatory cells with a variable degree of fibrous stroma. Occurrence in the extracranial head and neck in children is unusual, and involvement in the pterygopalatine fossa has not, to our knowledge, been reported as occurring in this age group. We present the CT findings of an IMT of the pterygopalatine fossa in a 6-year-old female patient with a 2-week history of fever and a painless swelling of the left cheek. The diagnosis of IMT should be included in the differential diagnosis of a child presenting with an aggressive mass associated with systemic features such as fever, elevated sedimentation rate, and leukocytosis.

Enhanced resting left ventricular filling in patients with successful coarctation repair and exercise-induced hypertension

M-mode and Doppler echocardiographic analyses of left ventricular (LV) shortening and filling were performed in 50 patients who underwent coarctectomy (median follow-up 9.5 years) and in 16 athletes in a control group before an exercise stress test with upright bicycle ergometry was performed. Thirty-two of 50 patients and 18 of 50 patients had a normotensive and hypertensive response to exercise, respectively. Preexercise echocardiographic data were compared among the control, normotensive, and hypertensive patient groups. LV peak filling rates (dD/dt, diastole) were increased in the hypertensive group (18.3 +/- 3.5) compared with those in the normotensive group (14.4 +/- 3.2; p < 0.001) and the control group (13.6 +/- 2.8; p < 0.001). LV shortening was enhanced in the coarctectomy group compared with that in the control group. A higher aortic isthmus Doppler gradient at peak exercise was not found in the hypertensive group compared with that in the normotensive group. Therefore patients with successful coarctectomy in childhood have enhanced LV shortening and relaxation at rest. Demonstration of enhanced LV peak filling rates may help identify patients at risk for exercise-induced hypertension.

Exercise performance following repair of hypoplastic left heart syndrome: A comparison with other types of Fontan patients

Reports of exercise performance after Fontan surgery for hypoplastic left heart syndrome (HLHS) are lacking. We compared the exercise performance of total cavopulmonary connection type (TCPC) of Fontan subjects with HLHS (group 1, n = 7) to those not requiring a Norwood procedure having a systemic right ventricle (group 2, n = 6) or a systemic left ventricle (group 3, n = 8). The subjects underwent assessment of resting pulmonary mechanics followed by maximal exercise testing with a bicycle or treadmill protocol. ECG, oxygen consumption, and carbon dioxide production were measured continuously. There was not a significant difference seen between HLHS and the comparison groups for the following parameters: maximum heart rate, maximum oxygen consumption, respiratory exchange ratio, breathing reserve, and arterial oxygen saturation at rest or exercise. Exercise performance in the TCPC type of Fontan patients was comparable regardless of ventricular morphology or surgical approach.

A new technique of uterine suspension to pectineal ligaments in the management of uterovaginal prolapse

The incidence of uterovaginal prolapse in young women is high in developing countries. Preservation of the uterus is of prime importance in the surgical management of these patients. A new technique of uterine suspension to the pectineal ligaments is presented as an alternative to traditional procedures. Through a Cherney incision, the uterus is suspended to the pectineal ligaments on both sides with mersilene tape. A simultaneous Burch colposuspension can be useful in selected cases. The operation has been done in 20 women, who averaged 27.5 years of age. There was no early or late morbidity during the follow-up period of 6-30 months. Of nine women desiring further childbearing, seven conceived within 6 months of surgery and thus far five have had an uneventful vaginal delivery at term; the other two have continuing normal gestations. There was no recurrence of prolapse at 6 weeks postpartum in any of the women.

The relationship between obesity, plasma immunoreactive insulin concentration and blood pressure in newly diagnosed Indian type 2 diabetic patients

The association of blood pressure with clinical and biochemical measures was studied in 185 newly diagnosed Type 2 diabetic patients, 74 impaired-glucose-tolerant (IGT) and 128 non-diabetic control subjects. Hyperglycaemic subjects were older than control subjects (controls 40 (24-59) years, IGT 48 (29-64) years, diabetic 43 (29-60) years, median (5th-95th centile) both p < 0.05). They were also more obese (body mass index (BMI) controls 23.5 kg m-2 (17.2-29.9), IGT 26.0 kg m-2 (19.8-33.9), diabetic 24.2 kg m-2 (19.3-32.2)) and with a greater waist-hip ratio (controls 0.83 (0.70-0.98), IGT 0.88 (0.75-0.98), diabetic 0.89 (0.75-1.00)). Blood pressure was significantly higher in both IGT (systolic 127 mmHg (108-162), diastolic 84 mmHg (66-99)) and diabetic patients (systolic 130 mmHg (104-160), diastolic 84 mmHg (66-102)) compared to non-diabetic controls (systolic 120 mmHg (100-151), diastolic 80 mmHg (60-94)). Univariate analysis showed that in diabetic patients systolic blood pressure was related to age (r = 0.17, p < 0.05), BMI (r = 0.23, p < 0.01) and plasma immunoreactive insulin (fasting and post glucose, r = approximately 0.25, p < 0.01) but not to C-peptide concentrations; diastolic blood pressure to BMI (r = 0.35, p < 0.001), waist-hip ratio (r = 0.23, p < 0.01) and plasma immunoreactive insulin (fasting r = 0.30, p < 0.001, post glucose r = approximately 0.20, p < 0.05) but not to C-peptide concentrations.(ABSTRACT TRUNCATED AT 250 WORDS)

Role of calcium in cholinergic stimulation of lacrimal gland protein secretion

To characterize the role of Ca2+ in cholinergic stimulation of lacrimal gland protein secretion, the effects of inhibitors of cellular Ca2+ handling on protein secretion were investigated. Protein secretion was measured from rat exorbital glands using either pieces of gland in perifusion or acini isolated by collagenase digestion. Peroxidase was used as a measure of protein secretion. An inhibitor of Ca2+ influx via voltage sensitive Ca2+ channels (verapamil) at 10(-5) and 5 X 10(-5) M did not alter protein secretion stimulated by the cholinergic agonist carbachol at 10(-5) M. Inhibition of Ca2+ efflux via Na+/Ca2+ exchange by removal of extracellular Na+ or by inhibition of Na+-K+-ATPase activity using ouabain (10(-3) M) or extracellular K+ removal did not stimulate protein secretion. In contrast, inhibition of Ca2+ release from intracellular stores with TMB-8 at 100 micron completely blocked protein secretion stimulated by carbachol at 10(-5) M. Similarly, the Ca2+/calmodulin (CaM) antagonists W-13 and W-12 decreased carbachol-induced protein secretion with potencies similar to those which inhibit Ca2+/CaM dependent processes. We conclude that cholinergic agonists stimulate lacrimal gland protein secretion primarily by mobilizing Ca2+ from intracellular stores and that one mechanism by which this Ca2+ could activate secretion is in conjunction with calmodulin.

Quantitative electromyography using automatic analysis--diagnostic utility of turns per unit amplitude

Quantitative electromyographic (QEMG) data from 3 muscles recorded with a 50-micronV threshold for the turns and amplitude measurements are presented. Using turns per unit amplitude as the index, consistent and comparable readings were recorded from abductor digiti minimi, biceps brachii and vastus medialis in normal subjects, namely 1.132 +/- 0.08 (31 subjects), 1.059 +/- 0.122 (31 subjects) and 1.007 +/- 0.088 (11 subjects), respectively. It is shown here that the diagnostic yield increases when all 3 values, namely, turns/s, average amplitude and turns/unit amplitude are considered in conjunction rather than considering the first 2 alone.

Quantitative electromyography using automatic analysis. A comparative study with a fixed fraction of a subject's maximum effort and two levels of thresholds for analysis

Quantitative electromyographic (QEMG) data recorded with two levels of threshold for the apparatus are compared. Using a fixed fraction of a subject's maximum effort the data are shown to be independent of sex, age and the strength of the muscles. The diagnostic yield of such a method is shown to be better with 50 muV threshold for analysis than with 100 muV, in cases of muscle disorders such as Duchenne muscular dystrophy and polymyositis. However, in cases of neurogenic lesions due to anterior horn cell disease the diagnostic yield remains the same with both thresholds.