scholarly journals Determination of the Accuracy of Linear Height Bone for Implant Placement in Panoramic Radiography Relative to CBCT in the Posterior Areas of the Jaws

2021 ◽  
pp. 604-611
Author(s):  
Sajad Ghorbanizade ◽  
Majid Zolfagharikhorshaneh ◽  
Fatemeh Gholamian ◽  
Mohamad Noori
Keyword(s):  
Panoramic Radiography ◽  
Mean Difference ◽  
Panoramic View ◽  
Height Measurement ◽  
Surgical Guide ◽  
Gutta Percha ◽  
Implant Placement ◽  
The Mean ◽  
Marked Points

Purpose: In the levels of implant treatment in the posterior region, determining the height of the bone has particular importance. The aim of the study was to compare the accuracy of linear bone height measurement for implant placement on panoramic view compared to CBCT in posterior jaw area. Materials and Methods: The study was performed on 20 patients. In each of the posterior edentulous areas, a surgical guide for each patient was marked with gutta-percha (a total of 70 points). Panoramic radiographs and CBCTs were obtained from the patients and then the distance between the marked points in the maxilla to the maxillary sinus and in the mandible to the upper border of the alveolar canal was measured by Romaxis software and analyzed by Statistical software Stata 14. The obtained measurements of panoramic view were compared to CBCTs using t-test. P≤0.05 was considered significant. Results: The mean difference between the sizes obtained from panoramic radiography and CBCT radiography in the maxilla was 0.34 mm (P = 0.57) and the mean difference between the sizes obtained from panoramic radiography and CBCT radiography in the mandible was 0.86 mm (P = 0.004). Conclusion: According to the results of study, it is logical panoramic radiography just used to pre-assessment of implant procedures in posterior area of mandible were as it could be more reliable in maxilla.

scholarly journals Effect of Surgical Guide Design and Surgeon's Experience on the Accuracy of Implant Placement

2012 ◽  
Vol 38 (4) ◽  
pp. 311-323 ◽  
Author(s):  
Simon Hinckfuss ◽  
Heather J. Conrad ◽  
Lianshan Lin ◽  
Scott Lunos ◽  
Wook-Jin Seong
Keyword(s):  
Coordinate Measuring Machine ◽  
Future Research ◽  
Positional Error ◽  
Guide Tube ◽  
Implant Position ◽  
Surgical Guide ◽  
Implant Placement ◽  
Measuring Machine ◽  
The Mean

Implant position is a key determinant of esthetic and functional success. Achieving the goal of ideal implant position may be affected by case selection, prosthodontically driven treatment planning, site preparation, surgeon's experience and use of a surgical guide. The combined effect of surgical guide design, surgeon's experience, and size of the edentulous area on the accuracy of implant placement was evaluated in a simulated clinical setting. Twenty-one volunteers were recruited to participate in the study. They were divided evenly into 3 groups (novice, intermediate, and experienced). Each surgeon placed implants in single and double sites using 4 different surgical guide designs (no guide, tube, channel, and guided) and written instructions describing the ideal implant positions. A definitive typodont was constructed that had 3 implants in prosthetically determined ideal positions of single and double sites. The position and angulation of implants placed by the surgeons in the duplicate typodonts was measured using a computerized coordinate measuring machine and compared to the definitive typodont. The mean absolute positional error for all guides was 0.273, 0.340, 0.197 mm in mesial-distal, buccal-lingual, vertical positions, respectively, with an overall range of 0.00 to 1.81 mm. The mean absolute angle error for all guides was 1.61° and 2.39° in the mesial-distal and buccal-lingual angulations, respectively, with an overall range of 0.01° to 9.7°. Surgical guide design had a statistically significant effect on the accuracy of implant placement regardless of the surgeon's experience level. Experienced surgeons had significantly less error in buccal-lingual angulation. The size of the edentulous sites was found to affect both implant angle and position significantly. The magnitude of error in position and angulation caused by surgical guide design, surgeon's experience, and site size reported in this study are possibly not large enough to be clinically significant; however, it is likely that errors would be magnified in clinical practice. Future research is recommended to evaluate the effect of surgical guide design in vivo on implant angulation and position error.

scholarly journals The accuracy of the determination of terrestrial refraction from reciprocal zenith angles

1979 ◽  
Vol 89 ◽  
pp. 203-212 ◽  
Author(s):  
K. Ramsayer
Keyword(s):  
Mean Difference ◽  
Mean Deviation ◽  
Refraction Coefficient ◽  
Refraction Angle ◽  
Observation Station ◽  
The Mean ◽  
True Values ◽  
Better Than

To investigate the accuracy of the determination of terrestrial refraction from reciprocal zenith angles and astronomical latitudes and longitudes at both ends of a line a test net with lines from 4 km to 23 km was observed and three dimensionally adjusted. As the measurements of the zenith angles were repeated every hour 40 times in an average the adjusted values were taken as a substitute for the true values. It is shown, that the mean refraction coefficient k, which is changing from k = 0.10 at day up to k = 0.34 at night, and the corresponding refraction angle can be determined very accurately, if both angles are measured simultaneously. Observations with day light are better than observations in the night. For observations with day light the mean difference between the true refraction angle at the observation station and the mean refraction angle of the observed line was smaller than ± 1″ independent of the length of the line. That means that the mean deviation of the true effective refraction coefficient in the observation station and the mean refraction coefficient of the observed line was inverse proportional to the distance.

scholarly journals Positioning accuracy assessment of minimally invasive percutaneous injection techniques for the treatment of temporomandibular disorders

2020 ◽  
pp. 20200313
Author(s):  
Antônio Luís Neto Custódio ◽  
Andrew Cameron ◽  
Mahmoud Bakr ◽  
Chris Little ◽  
Bruno Ramos Chrcanovic ◽  
...  
Keyword(s):  
Accuracy Assessment ◽  
Mean Difference ◽  
Virtual Planning ◽  
Percutaneous Injection ◽  
Mean Values ◽  
Surgical Guide ◽  
Injection Techniques ◽  
3D Printed ◽  
The Mean

Objective: The aim of the present study was to evaluate the accuracy of an extraoral CBCT-planned 3D-printed surgical guide aimed to percutaneous injection of substances into the temporomandibular joint (TMJ) and the lateral pterygoid muscle (LPM). Methods: Nine human cadaver heads were used. Pre-planning CBCT and facial scans were obtained and three percutaneous injection sites were planned: one for the lower compartment of the TMJ and two for the LPM. A digital surgical guide was then designed with small titanium sleeves and printed by a 3D printer. After the injections, new CBCT scans with the needles in place were obtained in order to assess the accuracy of the procedure in relation to the virtual planning. Results: The mean values for angle deviation were very low (range 1.13o-4.08o), the same happening for the mean difference in the length reached (range 1.82–2.64 mm), as well as for the mean difference in the needle tip dislocation (range 0.94–2.03 mm). Conclusion: The guide seems to be a reliable tool for accurate percutaneous injection of drugs into the inferior compartment of the TMJ and the LPM. Further studies are necessary to test the efficacy and validate the method in an in vivo study.

scholarly journals Comparison of Two Storage Methods for the Analysis of Cholinesterase Activities in Food Animals

2010 ◽  
Vol 2010 ◽  
pp. 1-11 ◽  
Author(s):  
Kasim Abass Askar ◽  
A. Caleb Kudi ◽  
A. John Moody
Keyword(s):  
Significant Inhibition ◽  
Mean Difference ◽  
Altman Plot ◽  
Choline Esters ◽  
Cholinesterase Activities ◽  
The Mean ◽  
Storage Methods ◽  
Lower Limits ◽  
Hydrolysis Of

Cholinesterases (ChE) are specialized carboxylic ester hydrolases that catalyse the hydrolysis of choline esters. They are classified into either acetylcholinesterase (AChE) or butyrylcholinesterase (BChE). Determination of ChE in the tissues is the appropriate tool for the diagnosis of organophosphorus and carbamate exposures. In general, a significant inhibition was seen in both AChE and BChE activities after 6 months of freezing at −80°C and after 3 months of freezing at −20°C. Linear regression of mean AChE and BChE was observed in all individual samples during the months of the two freezing methods. Bland and Altman plot of the ratios of the two freezing methods have showen the mean difference between the two freezing methods to be 8.8, and SD was 144.7 and −127.6 for upper and lower limits, respectively, for liver, while in muscle the mean difference was 1.5 and SD was 32.5 and −28.9 for upper and lower limits, respectively.

scholarly journals Agreement of Two Different Laboratory Methods Used to Measure Electrolytes

2011 ◽  
Vol 3 (02) ◽  
pp. 104-109 ◽  
Author(s):  
Venencia Albert ◽  
Arulselvi Subramanian ◽  
Kanchana Rangarajan ◽  
Ravindra Mohan Pandey
Keyword(s):  
Cross Sectional Study ◽  
Mean Difference ◽  
Universal Method ◽  
Limits Of Agreement ◽  
Serum Samples ◽  
Cross Sectional ◽  
Laboratory Methods ◽  
Flame Photometer ◽  
The Mean

ABSTRACT Aim: The aim of our study was to do an agreement analysis of two different laboratory methods used to measure electrolytes i.e., between the ISE based Beckman Coulter Synchron CX9 PRO Biochemistry analyzer and RAL′s Ion3 Flame Photometer (Técnica para el Laboratorio, Barcelona, Spain), in serum samples. Materials and Methods: This cross sectional study was done over a period of three months from September′09 through December′09 on routine biochemistry samples. A total of 6492 samples were received for routine biochemistry analysis from those 630 blood samples were randomly processed for this study. Two ml of sample was taken in a plain gel tube (LABTECH Disposables, Ahmedabad, India), centrifuged and further processed using both systems within one hour of the sampling to obtain the Na and K concentrations in the samples. The bias and variability of differences in measured values were analyzed according to Bland and Altman method. Results: Flame photometry method has drawbacks such as low throughput, requires manual operation, is a time consuming procedure. Ion selective electrodes technique is a more universal method for the high throughput determination of electrolytes in physiological samples; Beckman Coulter Synchron CX9 PRO is an example of such a system. The mean difference between the two methods (standard minus test) and 95% limits of agreement for sodium in serum was -7.8±17.3 (-42.2 to 26.6) and in urine was -22±41 (-104 to 60). Similarly, the mean difference between the two methods for potassium values in serum was found to be -0.25±0.75 (-1.75 to 1.25) and in urine was -5.3±38.9 (-83.1 to 72.5). With 95% confidence interval, the value of sodium and potassium as determined by both the methods lie between the upper and lower limit showing 95% limits of agreement. Conclusion: Good degree of agreement was seen on comparing the two methods for measuring the electrolytes; the use of Synchron CX9 in place of Flame photometer for electrolyte analysis in serum and urine is justified or use the two interchangeably.

scholarly journals Determination of plasma volume in anaesthetized piglets using the carbon monoxide (CO) method

2002 ◽  
Vol 36 (3) ◽  
pp. 344-350 ◽  
Author(s):  
J. K. Heltne ◽  
M. Farstad ◽  
T. Lund ◽  
M. E. Koller ◽  
K. Matre ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Plasma Volume ◽  
Evans Blue ◽  
Mean Difference ◽  
Limits Of Agreement ◽  
Administration System ◽  
Mean Values ◽  
Controlled Ventilation ◽  
The Mean

Based on measurements of the circulating red blood cell volume (VRBC) in seven anaesthetized piglets using carbon monoxide (CO) as a label, plasma volume (PV) was calculated for each animal. The increase in carboxyhaemoglobin (COHb) concentration following administration of a known amount of CO into a closed circuit re-breathing system was determined by diode-array spectrophotometry. Simultaneously measured haematocrit (HCT) and haemoglobin (Hb) values were used for PV calculation. The PV values were compared with simultaneously measured PVs determined using the Evans blue technique. Mean values (SD) for PV were 1708.6 (287.3)ml and 1738.7 (412.4)ml with the CO method and the Evans blue technique, respectively. Comparison of PVs determined with the two techniques demonstrated good correlation ( r = 0.995). The mean difference between PV measurements was -29.9 ml and the limits of agreement (mean difference ±2SD) were -289.1 ml and 229.3 ml. In conclusion, the CO method can be applied easily under general anaesthesia and controlled ventilation with a simple administration system. The agreement between the compared methods was satisfactory. Plasma volume determined with the CO method is safe, accurate and has no signs of major side effects.

scholarly journals Double Guided Surgery in All-on-4® Concept: When Ostectomy Is Needed

2018 ◽  
Vol 2018 ◽  
pp. 1-7
Author(s):  
Gabriele Tonellini ◽  
Raquel Saez Vigo ◽  
Giorgio Novelli
Keyword(s):  
Survival Rate ◽  
Survival Rates ◽  
Surgical Guide ◽  
Guided Surgery ◽  
Implant Placement ◽  
Thin Bone ◽  
The Mean ◽  
Edentulous Jaws ◽  
Surgical Templates

Background. The rehabilitation of edentulous jaws with guided and flapless surgery applied to the All-on-4 concepts is a predictable treatment with a high implant and prosthetic survival rates, but there are several contraindications for this technique like when bone reduction is needed due to a high smile line in the maxilla or when there is an irregular or thin bone crest. Purpose. To report a technique with double guided surgery for bone reduction and implant placement with the All-on-4 concept. Materials and Methods. 7 patients were included in the study. Guided implant planning was performed using CBCT, and the virtual templates were created with three dedicated software. Custom surgical templates were made for the ostectomy and for implants positioning. Results. 28 implants were placed using a double bone-supported surgical guide. The mean angular errors between the preoperative-planned implant and the postoperative-placed implant were 2.155° ± 2.03°; the mean distance errors between the planned and the placed implants were 0.763 mm ± 0.55 mm on the shoulder implant and 0.570 mm ± 0.40 mm on the apex implant. Conclusions. The results of our study indicate that this treatment is predictable with an excellent survival rate allowing excellent results even when bone reduction is mandatory.

Detection of Circulating Tissue Factor and Factor VII in a Normal Population

1996 ◽  
Vol 75 (05) ◽  
pp. 772-777 ◽  
Author(s):  
Sybille Albrecht ◽  
Matthias Kotzsch ◽  
Gabriele Siegert ◽  
Thomas Luther ◽  
Heinz Großmann ◽  
...  
Keyword(s):  
Tissue Factor ◽  
Normal Population ◽  
Mean Value ◽  
Factor Vii ◽  
Significant Difference ◽  
Age Dependent ◽  
The Mean ◽  
Highly Correlated ◽  
And Gender

SummaryThe plasma tissue factor (TF) concentration was correlated to factor VII concentration (FVIIag) and factor VII activity (FVIIc) in 498 healthy volunteers ranging in age from 17 to 64 years. Immunoassays using monoclonal antibodies (mAbs) were developed for the determination of TF and FVIIag in plasma. The mAbs and the test systems were characterized. The mean value of the TF concentration was 172 ± 135 pg/ml. TF showed no age- and gender-related differences. For the total population, FVIIc, determined by a clotting test, was 110 ± 15% and the factor VIlag was 0.77 ± 0.19 μg/ml. FVII activity was significantly increased with age, whereas the concentration demonstrated no correlation to age in this population. FVII concentration is highly correlated with the activity as measured by clotting assay using rabbit thromboplastin. The ratio between FVIIc and FVIIag was not age-dependent, but demonstrated a significant difference between men and women. Between TF and FVII we could not detect a correlation.

Determination of Plasminogen in Clots and Thrombi

1966 ◽  
Vol 16 (01/02) ◽  
pp. 038-050 ◽  
Author(s):  
Ulla Hedner ◽  
Inga Marie Nilsson ◽  
B Robertson
Keyword(s):  
Mean Value ◽  
Main Mechanism ◽  
Clot Lysis ◽  
Post Mortem ◽  
Digestion Time ◽  
Normal Volunteers ◽  
Casein Solution ◽  
The Mean

SummaryThe plasminogen content was determined by a casein method in plasma and serum from 20 normal volunteers. The mean plasminogen content was found to be 10.1 ACU (the arbitrary caseinolytic unit defined in such a way that using a 3% casein solution and a digestion time of 20 min. at 37°C, 10 ACU gave an extinction of 0.300). No difference between serum and plasma regarding the plasminogen content was found.Plasminogen was determined in drained and drained plus washed clots prepared from 2 ml plasma. The highest values found in the drained clots were 0.9 ACU/clot and 0.2 ACU/clot in the drained plus washed clots.Plasminogen was also determined in drained and drained plus washed clots prepared from plasma with added purified plasminogen. The plasminogen was recovered in the washing fluid. According to these tests, then, purified added plasminogen is washed out of the clots.The plasminogen content of 20 thrombi obtained post mortem was also determined. The mean value was found to be 0.7 ACU/cm thrombus. Judging from our results, the “intrinsic clot lysis theory” is not the main mechanism of clot dissolution.

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