Plasma C-terminal pro-endothelin-1 is associated with left ventricular mass index and aortic root diameter in African-American adults with hypertension.

Endothelin-1 (ET-1), a circulating vasoactive peptide with potent vasoconstricting and mitogenic properties, may contribute to target-organ damage in hypertension. We investigated whether plasma levels of C-terminal pro-endothelin-1 (CT-pro-ET-1) are associated with left ventricular (LV) mass and aortic root diameter in African-American adults with hypertension. Plasma CT-pro-ET-1 was measured by an immunoluminometric assay in 1041 African Americans (65±9 years, 72% women) with hypertension. LV mass and aortic root diameter were measured according to the American Society of Echocardiography guidelines, and LV mass was indexed by height to the power 2.7 (LVMi). Multivariable regression analyses were used to assess whether plasma CT-pro-ET-1 was associated with LVMi and aortic root diameter, independent of potential confounding variables. Plasma CT-pro-ET-1 was modestly correlated with LVMi (r=0.21, P<0.0001) and aortic root diameter (r=0.09, P=0.004). In separate multivariable regression models that adjusted for age, sex, body mass index, total and high-density lipoprotein cholesterol, smoking history, diabetes, history of myocardial infarction or stroke, and blood pressure-lowering medication and statin use, log CT-pro-ET-1 was significantly associated with greater LVMi (P=0.001) and larger aortic root diameter (P=0.006). CT-pro-ET-1 is independently associated with LVMi and aortic root diameter and may be a marker of target-organ damage in African-Americans adults with hypertension.

Shaping canals with ProFiles and K3 instruments: does operator experience matter?

OBJECTIVE: The aim of this study was to determine the influence of operator experience on the shaping ability of ProFile and K3 nickel-titanium rotary instruments in simulated root canals. STUDY DESIGN: One hundred sixty simulated canals consisting of 4 different shapes in terms of angle and position of curvature were prepared by experienced and inexperienced operators. One experienced operator prepared 80 canals and 2 inexperienced operators prepared 80 canals with a crown-down technique using either ProFile or K3 .06 taper instruments. Images of the canals were taken, using a camera attached to a computer with image analysis software, before surgery and after preparation to sizes 20, 25, and 30 to working length. Postoperative images were combined with the preoperative image to highlight the amount and position of material removed during preparation as well as the shape of the prepared canal. RESULTS: Overall, there was a highly statistically significant difference (P<.001) between the instruments for the time taken to prepare the canals, with K3 instruments taking a mean of 4.9 minutes and ProFile 6.0 minutes. Six instruments fractured (3 in each operator category); 4 were ProFile instruments. Four instruments deformed, all with the inexperienced operators; 3 were K3. No perforations or zips were observed; however, 1 danger zone (created by the experienced operator using K3 instruments) and 1 ledge (created by an inexperienced operator using K3 instruments) were created. Twelve outer widenings were created with a highly significant difference (P<.001) between the operator and instrument used. There was a highly significant difference by instrument (P<.001), and experience (P=.008) regarding absolute transportation at the beginning of the curve and a statistically significant difference (P=.031) for the instrument used regarding absolute transportation half way to the orifice. CONCLUSION: The experienced operator prepared canals more quickly and safely than the inexperienced operators when using K3 instruments; both used ProFile instruments quickly and safely. Inexperienced operators would be advised to train using less aggressive instruments and when confident could progress to other instrument designs.

Smoking and caries experience in subjects with various form of periodontal diseases from a teaching hospital clinic.

OBJECTIVE: The aim of this study was to assess the relationships between aggressive periodontitis (AgP), caries and smoking. METHOD AND MATERIALS: A cross-sectional study was conducted among patients who were specifically referred to the Dental Teaching Clinic in Irbid, Jordan for periodontal treatment. Self-administered questionnaire related to socio-demographic data and smoking habits was completed. The oral hygiene, gingival status, periodontal health and dental status of the participants was determined by using the plaque index of Silness and Loe [Acta Odontol Scand, 22 (1964), 121], the gingival index of Loe and Silness [Acta Odontol Scand, 21 (1963), 233], clinical attachment level (CAL) and decayed, missing and filled teeth (DMFT) index respectively. RESULT: The prevalence of smoking was greater in chronic periodontitis (CP) group (44.2%) than in either chronic gingivitis (CG) (27.4%) or AgP (29.9%) group. Self-reported perio-diseases in the close family was more prevalent (77%) among subjects diagnosed with AgP. The mean plaque scores were significantly higher for smoker than non-smoker in AgP group only (P = 0.04), with significantly greater plaque and gingival scores in CG and CP groups than AgP group (P = 0.012, 0.004). A significantly greater mean gingival scores were noted among CG and CP groups than AgP group (P = 0.004). The mean CAL was higher in smokers than in non-smokers in the three groups, with statistically significant differences in CP and AgP groups (P = 0.04, 0.01 respectively).The mean number of DMFT was significantly higher in smoker than in non-smoker of all age groups (P = 0.016, 0.043 and 0.01). However, mean DMFT was significantly greater in CP and CG than AgP groups. CONCLUSION: It was concluded that (i) higher plaque and gingival index among smokers in all groups; (ii) significant difference in the CAL between smoker and non-smoke in CP and AgP groups; (iii) significant increase in caries risk among smokers in all groups; (iv) smokers and non-smokers of AgP group had significantly lower mean DMFT scores than those of CG or CP groups.

Radiographic technical quality of root canal treatment performed by dental students at the Dental Teaching Center in Jordan.

OBJECTIVES: The objective of this study was to evaluate radiographically the technical standard of root canal treatment performed by undergraduate dental students at the Dental Teaching Center in Jordan. METHODS: A random sample of 8500 records of dental patients was examined. A total of 542 endodontically treated teeth with 912 roots were evaluated. Periapical radiographs were used to assess the technical quality of the root canal filling. The length of each root canal filling was categorized as acceptable, short and overfilled based on their relationship with the radiographic apex. Density and taper of filling was evaluated based on the presence of voids and the uniform tapering of the filling, respectively. Chi-square analysis was used to determine statistically significant differences between adequacy of root canal filling in each group of teeth according to its location, position and curvature. RESULTS: Sixty-one percent of roots had fillings of acceptable length, while 34.5% were short and 4.2% were overfilled. The root canal fillings of 47.4% were found to be adequate. Adequate fillings were found more in maxillary than mandibular teeth (P < 0.005), anterior compared to posterior teeth (P < 0.05) and in straight canals compared to curved canals (P < 0.001). CONCLUSION: The technical quality of root canal treatment performed by undergraduate dental students using step-back preparation and lateral condensation was found to be less than 50%. Review of the endodontic curriculum requirements, specialized clinical supervision and increasing the time of training at the preclinical and clinical levels should improve this quality.

Clinical problems associated with unusual cases of talon cusp.

CASE REPORT: Talon cusp is an uncommon dental anomaly manifested as an accessory cusp-like structure on the crown of anterior teeth. This report describes two unusual cases of talon cusp. Case 1 showed bilateral anomalous cusps on the palatal aspects of maxillary supernumerary teeth, causing premature contact and tooth impaction. In case 2, a double-fused talon cusp was projected from the palatal surface of a large geminated central incisor. A talon cusp is not an innocuous defect, as it may provide a substantial diagnostic, treatment planning and procedural challenge. Early diagnosis and management are important to avoid complications.

Shaping ability of Profile rotary nickel-titanium instruments with ISO sized tips in simulated root canals: Part 1.

The aim of this study was to determine the shaping ability of ProFile 0.04 taper rotary nickel-titanium instruments with ISO sized tips in simulated canals. A total of 40 simulated root canal made up of four different shapes in terms of angle and position of curvature were prepared by ProFile instruments using the 'crown down' approach recommended by the manufacturer. Part 1 of this two-part report describes the efficacy of the instruments in terms of preparation time, instrument failure, canal blockages, loss of canal length and three-dimensional canal form. The time necessary for canal preparation was on average 5.2 min and was not influenced significantly by canal shape. Three instrument fractures occurred and a further 3 instruments deformed; size 35 instruments failed the most (4) followed by size 30 (2), four of the failures occurred in canals with 40 degrees curves. None of the canals became blocked with debris and change in working distance was minimal. Intra-canal impressions of canal form demonstrated that most canals had apical stops and smooth canal walls whereas all canals had good flow and taper. Under the conditions of this study, ProFile 0.04 taper rotary nickel-titanium instruments with ISO sized tips prepared simulated canals rapidly and created good three-dimensional form.

Shaping ability of ProFile rotary nickel-titanium instruments with ISO sized tips in simulated root canals: Part 2.

The aim of this study was to determine the shaping ability of ProFile 0.04 taper rotary nickel-titanium instruments with ISO sized tips in simulated canals. A total of 40 simulated root canals made up of four different shapes in terms of angle and position of curvature were prepared by ProFile instruments using the 'crown down' approach recommended by the manufacturer. Part 2 of this two-part report describes the efficacy of the instruments in terms of prevalence of canal aberrations, the amount and direction of canal transportation and the overall post-operative shape. Out of 37 completed specimens 9 zips (24%) and one ledge (3%) were created, but no perforations or danger zones were found. There were significant differences (P < 0.01) between canal shapes for the incidence of zips and elbows but not for their distance from the end-point of preparation. At specific positions along the canal length there were significant differences between the canal types in terms of their mean total width; overall, at the end-point of preparation and along the curved portion of the canals those specimens with 40 degrees curves were widest. This trend continued for the width of material removed from the outer aspect of the canal curves, whereas along the inner aspect of curves more material was removed in the 20 degrees canals. Overall, transportation was towards the outer aspect of the curve at the end-point of preparation and along the curved portion of canals but more balanced along the straight coronal section. Absolute transportation was small and below 0.1 mm at every position including the zips. Under the conditions of this study, ProFile nickel-titanium rotary instruments with ISO sized tips produced a larger number of zips than expected; however, the degree of zipping was limited and relatively minor.

Comparison of the performance of four files with rounded tips during shaping of simulated root canals.

A total of 160 simulated canals of various angles and positions of curvature were prepared by hand using either Mani Flexile Files, Mani SEC-O Files, Maillefer Flexofiles, or Zipperer Flexicut Files. After orifice enlargement, each file type was used to prepare 40 canals employing a balanced force motion and a modified double-flared technique. Pre- and postoperative images of the canals were taken with a videocamera, and stored and manipulated in a computer with image analysis software. The presence of canal aberrations and the amount of material removed as a result of preparation were determined from composite images of superimposed pre- and postoperative views. Significant differences (p < 0.001) in preparation time were observed, with Flexile Files being quickest and SEC-O Files being slowest. Overall, Flexofiles and Flexicut Files deformed significantly more (p < 0.001) than Flexile and SEC-O Files. The incidence of canal blockage was not influenced by instrument type, but the incidence of apical extrusion was significantly greater (p < 0.001) with SEC-O Files. SEC-O Files created significantly fewer (p < 0.001) and significantly narrower (p < 0.001) zips, with significantly less (p < 0.001) removal of material from the outer aspect of the curve and thus significantly less (p < 0.001) transportation. Flexicut Files created the widest canals apically, with the greatest removal of material from the outer aspect of the curve and the most transportation. Flexofiles created significantly more (p < 0.001) perforations. Under the conditions of this study, obvious differences between instruments were highlighted with SEC-O Files preparing canals more safely and with least destruction. The unique rounded tip of the SEC-O Files may have had an influence on the outcome.

Oral Health survey at an air base in Jordan

The aim of this investigation was to assess the severity and prevalence of periodontal disease and dental caries in 507 subjects, ranging in age from 15 to 44 years, at an army air base in Jordan. Using the Community Periodontal Index for Treatment Needs [CPITN], it was found that prevalence of periodontal disease increased with age, but incidence of caries, gingivitis and calculus was alarmingly high in young adults [20-24 years]. Overall, the rate of decayed, missing and filled teeth [DMFT] is rising, a trend that has been noted in similar studies from other developing countries

Arsenical necrosis of the jaws.

After a brief historical review of the use of arsenic in dental practice two cases of arsenical necrosis of the jaws, affecting the maxilla and mandible respectively, are reported. Both patients were treated conservatively over an extended period with excellent results. It is concluded that there is no justification, whatsoever, for the use of arsenic in modern dental practice and that, although prolonged, conservative treatment of chemical necrosis of the jaws is preferable to more radical treatment.

Pattern of bacterial infections and antimicrobial susceptibility at the Kenyatta National Hospital, Nairobi, Kenya.

To monitor clinically significant isolates and their antimicrobial susceptibilities, all specimens sent to microbiology laboratory of the Kenyatta National Hospital were cultured on appropriate media. The susceptibility of the isolates was performed on Muller Hinton or diagnostic sensitivity test (DST) agar using comparative discs diffusion technique. The results were then entered into Microbe Base 2 computer programme. A total of 7416 clinically significant isolates were collected from 1991 to 1995. The most commonly isolated organisms were E.coli, Klebsiella and Staphylococcus aureus. Most of these hospital acquired infections had multiple resistance to conventional antimicrobials, namely, penicillin, tetracyclines, gentamicin, trimethoprim/sulphamethoxazole and ampicillin. The resistance pattern was high among both gram negative and positive bacteria isolates. Beta-lactamase production amongst them were 51%, 69.3%, 79.6% respectively. Prevalence of methicillin resistant Staphylococcus aureus was 39.8%. Addition of clavulanic acid to amoxycillin increased Staphylococcus aureus susceptibility three fold. The emergence of multiple drug resistance calls for a continuous monitoring and reviewing of antibiotic policy in the hospital and the country at large.

Survey of penicillin resistant pneumococci at Kenyatta National Hospital, Nairobi.

During a four year period, a survey of antibiotic sensitivity patterns in clinical isolates of pneumococci was conducted at Kenyatta National Hospital, Nairobi. The isolation and characterisation of Streptococcus pneumoniae was done using standard laboratory procedures. Sensitivity testing was by disc diffusion method using discs supplied by Oxoid. During the period, 45 clinical isolates were recorded. This figure is somewhat lower than the expected rate of pneumococcal isolation at the hospital. Penicillin resistance of 24% among the pneumococcal isolates was recorded. Among the antibiotics tested, amoxycillin/clavulanic acid, ceftazidime, erythromycin and chloromphenicol had highest activity against the pneumococci. Surprisingly low sensitivity rates were recorded for trimethoprim/ sulphamethoxazole and cefuroxime. Implications of these findings in the management of pneumococcal infections are discussed.

Community acquired bacterial infections and their antimicrobial susceptibility in Nairobi, Kenya.

The purpose of the study was to determine the pattern and antimicrobial sensitivity on community acquired bacterial strains in Nairobi, Kenya. Clinical specimens collected from out-patient clinics at the Kenyatta National Hospital were cultured on appropriate media and identified according to Cowen and Steel's manual. The antimicrobial sensitivity was determined using comparative disc diffusion techniques. Between 1991 and 1995, there were a total of 1659 positive cultures comprising 30 different bacterial species. Out of the overall gram negative isolates (61.9%), E.coli and Klebsiella spp formed over 70%. Among the gram positive, Staphylococcus aureus, Enterococcus and coagulase negative staphylococcus spp constituting 41%, 26% and 18% respectively were the most common. Most organisms showed multiple resistance patterns to commonly used antimicrobials similar to hospital acquired infections. The gram negative isolates were resistant to cotrimoxazole, ampicillin, tetracyclines, chloramphenicol, and sulphamethoxazole. However, the sensitivity of these organisms to gentamicin and kanamycin was between 60 and 90%. Among the gram positive isolates, there was a high resistance to penicillin and tetracyclines (60-90%) while the resistance to lincomycin, minocycline and chloramphenicol was low (5-50%). All isolates were, however, highly sensitive to cephalosporins and fluoroquinolones. Beta-lactamase production among, E.coli, Klebsiella spp and Staphylococcus aureus was 48.9%, 76.7%, 76.1% respectively. Methicillin resistance for Staphylococcus aureus was 59.2%. Indiscriminate use of antibiotics in the community may have selected for resistant strains. This calls for urgent need to review policies on prescription practices.

Comparison of two stainless steel files to shape simulated root canals.

The aim of this study was to compare the shaping ability of two stainless steel files using simulated canals. A total of 80 simulated canals of various angles and positions of curvature were prepared by hand using either Mani K-Files or Micro Mega K-Files. Following orifice enlargement each file type was used to prepare 40 canals employing a linear filing motion and an anticurvature stepback technique. Pre- and post-operative longitudinal images of the canals were taken with a video camera and stored and manipulated in a computer with image analysis software. The presence of canal aberrations and the amount of material removed as a result of preparation were determined from composite images of superimposed pre- and post-operative views. Overall, canal preparation with Mani K-Files was significantly quicker (P < 0.005) and was associated with fewer instrument failures. Zips and elbows were observed in 70% of specimens with significantly more (P < 0.05) occurring following preparation with Micro Mega K-Files. Mani K-Files created significantly more (P < 0.01) danger zones. Micro Mega K-Files created significantly wider (P < 0.001) zips with significantly more (P < 0.01) resin removed from the outer aspect of the curves and, thus, significantly more (P < 0.01) transportation. Canal shape had a significant influence on preparation time (P < 0.001), the incidence of zips (P < 0.05) and danger zones (P < 0.005), the width of zips (P < 0.001) and transportation at the zips (P < 0.001). Under the conditions of this study, Mani K-Files were more effective than Micro Mega K-Files and produced canals with better shapes. Original canal shape had a substantial influence on the outcome of shaping procedures.

Relationship of cyclosporine and gingival overgrowth.

Cyclosporine is used as an immunosuppressive agent in organ transplantation. It has several side effects including gingival overgrowth. We evaluated 30 renal transplant patients on cyclosporine for the degrees of the gingival overgrowth. All the patients were males with mean age of 37.5 years. Eighteen patients (60%) had moderate to severe degrees of gingival overgrowth. No correlation was found with the trough levels of cyclosporine in blood. We conclude that gingival overgrowth is associated with cyclosporine immunosuppressive therapy but may not be dose related. The effect of other factors such as dental plaque and oral hygiene should be further studied.

Canal blockage and debris extrusion with eight preparation techniques.

The objective of this study was to assess and compare canal blockages and apical extrusion of dentin debris during canal shaping with eight preparation techniques. A total of 208 canals in extracted human teeth were prepared by one operator using one type of file. The techniques included were standardized, stepback with reaming, stepback with circumferential filing, stepback with anticurvature filing, double-flare, stepdown, crown-down pressureless, and balanced force. Records were kept of the number of canals that became permanently blocked with debris at some stage during preparation. Dentin debris extruded apically was collected in preweighed containers and the dry weight of debris determined to 10(-5) g precision. Blockages varied significantly among techniques (p < 0.001) and occurred most frequently in canals prepared with the stepback techniques with anticurvature (n = 19) and circumferential filing (n = 16) and least in the balanced force technique (n = 0). Apical extrusion occurred in 169 of the 208 roots, but there were no significant differences in the incidence of extrusion among techniques. The weight of extruded dentin did vary significantly among techniques (p < 0.05), with most extrusion occurring with the stepback techniques with circumferential (0.71 mg) and anticurvature (0.69 mg) filing and the least extrusion with the balanced force (0.38 mg) and crown-down pressureless (0.46 mg) techniques. Under the conditions of this study, it is concluded that techniques involving a filing (linear) motion caused significantly more blockages and extruded significantly more apical dentin debris.

Comparison of six files to prepare simulated root canals. 1.

A total of 300 simulated root canals of various angles and positions of curvature in clear resin blocks were prepared by hand using either K-files, K-Flex files, Flexofiles, Flex-R files, Hedstrom files or Unifiles. Each file type was used to prepare 50 canals employing a linear filing motion and an anticurvature stepback technique. Part 1 of this two-part report describes the efficacy of the files in terms of preparation time, instrument failure, loss of canal length and weight loss from the blocks. Two-way analysis of variance confirmed that there was significant variation for each parameter between instruments, between canal types, and with interaction between instruments and canal types. Overall, preparation with Hedstrom files was significantly quicker than with any other file, whilst preparation with K-files and K-Flex files took significantly longer. Fracture and deformation of instruments occurred substantially less often with Flex-R and Hedstrom files, but significantly more often with Unifiles. Loss of working distance occurred with all file types, but was significantly greater in canals prepared with K-files. Unifiles and Hedstrom files were responsible for significantly more weight loss than the other files, whilst K-files produced significantly less weight loss. Canals with rough undulating walls were created most often by Hedstrom files and Unifiles. Overall, under the conditions of this study, Flexofiles, Flex-R files and Hedstrom files appeared to be substantially more effective than K-files, K-Flex files and Unifiles.