scholarly journals Comparative Study Qualitative and Quantitative Techniques in the Study of Occlusion

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Tanya Bozhkova ◽  
Nina Musurlieva ◽  
Diyan Slavchev

Introduction. The wide variety of methods for recording occlusal contacts and the contradictory data on the interpretation of the obtained markings provoked us to make a comparative laboratory study between different occlusal indicators. Purpose. Evaluation of a qualitative and quantitative method for registration of occlusal contacts in static occlusion in laboratory conditions. Materials and Methods. In completion of the objective, we designed an apparatus for registration of the occlusal contacts (AROC) in static occlusion which is used, corresponding to the MIP in clinical conditions. The occlusal indicators that were included in the study were articulating paper 100 μ, articulating foil 12 μ, and T-Scan Novus system with a sensor thickness of 100 μ. The collected primary statistical information was entered and processed with the statistical package SPSS Statistics 19.0, and the graphs were prepared using Microsoft Office 2019. We performed descriptive statistical analysis in this study. Comparisons were performed using one-way analysis of variance (ANOVA), Student’s t -test, and Pearson coefficient method. For a significance level, p < 0.05 was chosen. Result and Discussion. With quality occlusal indicators, it is possible only to visually determine the size, number, and intensity of the marked contacts. After the statistical processing of the obtained data on the number of registered contacts, a significant difference is found in the number of contacts of certain teeth (18, 24, 25, 28, 38, 35, 34, 33, 44, 45, and 48) registered with articulating paper and articulating foil. The maximum force that is reported during the study with the T-Scan system is 93.72% and the forces in the right half of the dentition are 51.7% and in the left 48.9%. To visualize the location of the registered occlusal contacts with the system, it is intraoral to use a quality indicator and we recommend the use of articulating foil. Conclusion. Based on findings from the current in vitro simulation, we can conclude that the type of occlusal indicator influences the registration of contacts, and therefore, we propose as a method of choice to achieve a balanced occlusion in clinical practice to combine the use of one conventional and one quantitative method.

2020 ◽  
pp. 232020682095394
Author(s):  
Özgecan S¸ivet ◽  
Özlem Malkondu ◽  
Sercan Küçükkurt ◽  
Ender Kazazoglu

Aim: To evaluate the changes in the temperature of zirconia during grinding under different clinical conditions. Materials and Methods: A total of 60 zirconia framework specimens were fabricated and divided into groups of 10 specimens each. Two different handpieces, namely, a high-speed handpiece (HSH) and a low-speed handpiece (LSH), were used for grinding with and without water cooling. Fine- and coarse-grit diamond burrs were used with the HSH, separately. The following six groups were created: (a) HSH fine-grit with water cooling, (b) HSH coarse grit with water cooling, (c) HSH fine grit without water cooling, (d) HSH coarse grit without water cooling, (e) LSH with water cooling, and (f) LSH without water cooling. Each zirconia framework was ground until 1 mm3 of the material was removed. Temperature values corresponding to the grinding techniques were compared and statistically analyzed. One-way analysis of variance was used to compare the group parameters, while the Tukey honest significant difference test was used to detect significant differences between the groups. The significance level was set at P <.05. Results: The highest mean temperature was measured in the case of grinding with the LSH without water cooling (54.7 °C ± 11.6 °C), while the lowest mean temperature was observed in the case of grinding with the HSH using the coarse-grit diamond rotary instrument under water cooling (22.6 °C ± 0.6 °C). Conclusions: The grinding of zirconia must be performed with an HSH under water cooling. Further, when water cooling is used, neither the type of handpiece nor the grain type of the rotary instrument used as it has a significant effect on the temperature.


Author(s):  
Agustinus Februadi ◽  
Nono Wibisono ◽  
Dewi Purnamasari

Bandung is a popular tourist destination in Indonesia and a gateway for tourists who visit destinations around greater Bandung areas. Currently, Bandung is also known as a culinary, shopping, and nature tourism destination. Past studies have measured the image of Bandung as a tourist destination. However, the measurements were done partially due to the use of quantitative method only. Thus, the results were not comprehensive. To resolve the drawbacks of the previous studies, this study used both qualitative and quantitative approaches. Data were collected from 430 domestic tourists by ways of structured and unstructured interviews in 20 different destinations in Bandung and the surrounding. Data were processed by descriptive statistical methods, factor analysis and content analysis. The results of quantitative analysis show that, in term of functional-attribute, Bandung was positively perceived as a destination characterized with natural scenic beauty, many interesting places, and various exotic foods. In terms of the psychological-attribute, Bandung was perceived as the right place for shopping and culinary tourism. The results of qualitative analysis indicate that, functionally, Bandung was a destination with natural scenic beauty, pleasant weather and provide various exotic foods. Psychologically, the tourists experienced calm and tranquil atmosphere, happiness, and comfort.


Author(s):  
Larissa Chaves Cardoso FERNANDES ◽  
Patrícia Moreira RABELLO ◽  
Bianca Marques SANTIAGO ◽  
Marcus Vitor Diniz de CARVALHO ◽  
Manoel Raimundo de SENA JÚNIOR ◽  
...  

ABSTRACT Objetive To determine the percentage of correctness of the Orbital Index (OI) for estimation of sex, ancestry and age in Brazilian skulls. Methods Cross-sectional study of 183 human dry skulls from the southeastern Brazil. A total of 100 skeletons were males and 83 females; of which 36 were aged up to 39 years, 60 aged between 40 and 59 years, and 87 aged 60 years or older. As for ancestry, 103 were from white, 51 mixed race, and 29 black individuals. The OI was calculate by the formula = height/width x 100. The data were submitted to Student’s t test, F (ANOVA), Tukey and Kruskal Wallis tests as well as to discriminant analysis, with a 5% significance level. Results The sample was characterized as mesoseme, with a mean age of 56.62 (±19.97) years. No significant difference was observed (p=0.511) between the OI in females (right: 86.43 ± 6.58 and left: 86.70 ± 5.93) and males (right: 85.78 ± 6.69 and left: 86.37 ± 6.20). There were no significant differences between age, ancestry and the variables analyzed (p>0.05). The right and left orbital widths were significantly dimorphic between sexes (p<0.001). The percentage of correctness of the method for estimation of sex, age and ancestry was found to be 65.6%, 43.7%, and 43.6%, respectively. Conclusions The OI is not an appropriate method for estimation of sex, ancestry and estimation of age in this Brazilian sample. The methodology should be expanded to other population groups so that it can be improved.


2020 ◽  
Vol 46 (2) ◽  
pp. 163-171
Author(s):  
Cecília Alves de Sousa ◽  
Maria Beatriz Bello Taborda ◽  
Gustavo Antônio Correa Momesso ◽  
Eduardo Passos Rocha ◽  
Paulo Henrique dos Santos ◽  
...  

The purpose of this systematic review was to evaluate the literature available for materials exhibiting the best efficacy in preventing biofilm formation in the interior of implants. We searched PubMed/MEDLINE, Scopus, and Cochrane databases. This review is registered with the PROSPERO database and followed the suitability of the PRISMA protocol. The initial search resulted in 326 articles from the databases. After they were read, 8 articles remained, and the inclusion and exclusion criteria were applied. Six of these 8 articles were classified as in vitro and 2 were classified as in situ. The regions of the implants evaluated ranged from the interface of the pieces to the occlusal upper access of the abutment. The implant connections evaluated the Morse taper, external connection, and internal connection. Meta-analysis of the quantitative data was performed at a significance level of .05. Cotton exhibited poor control of infiltration, even in combination with other materials. Isolated gutta-percha (GP) and polytetrafluoroethylene (PTFE) tape with composite resin (CR) or GP performed better as physical barriers. The best results for chemical barriers were observed by the application of 1% chlorhexidine gluconate (CG) gel, thymol varnish, and the deposition of Ag films onto the surface. The applied meta-analysis did not show a significant difference in comparison between the different types of implant connections (P &gt; .05). The application of CG and thymol varnish antimicrobials was effective in preventing biofilm formation and easy clinical execution; these could be used in combination with CR, GP, and PTFE.


2019 ◽  
Vol 29 (1) ◽  
pp. 33103
Author(s):  
Viviane Leite ◽  
Lisiane Piazza Luza ◽  
Sara Maria Soffiatti Dias ◽  
Thamara Caviquioni ◽  
Ediane Roberge Fernandes Zampirolo ◽  
...  

AIMS: To evaluate the posture of subjects with lower limb amputee.METHODS: Ten subjects participated in the study, males, with 38,2 ± 8,2 years, with unilateral lower limb amputation and prosthesis users. For the postural evaluation, the Postural Evaluation Software (SAPO) was used, and the images were evaluated according to the software protocol. Data were analyzed through descriptive and inferential statistics (independent t test), with a significance level of p ≤ 0,05.RESULTS: The main alterations observed were: rearfoot valgus enlargement, flexed ankle, head tilted to the right and trunk in flexion. When compared the posture according to time of amputation, was observed a statistically significant difference in the horizontal asymmetry of scapula in relation to T3 (p = 0,004), being that subjects with amputation time of up to six years presented the left scapula higher than the right one (-5,28 ± 8,16°) and those with more than six years of amputation had the right upper right scapula (19,42 ± 11°). In the comparison between amputation levels, there was a statistically significant difference in the ankle angle (p = 0,008), with subjects with amputation below the knee presenting greater ankle flexion (81,97 ± 1,72°) than those with amputation at the level of the knee and above this (87,30 ± 2,65°).CONCLUSIONS: The findings of the present study demonstrate that all the evaluated subjects presented some postural alteration, however, it cannot be affirmed that the postural asymmetry of these is due to the amputation.


2010 ◽  
Vol 11 (5) ◽  
pp. 25-32 ◽  
Author(s):  
Hamideh Ameri ◽  
Marjaneh Ghavamnasiri ◽  
Ehsan Abdoli

Abstract Aim This study evaluated the influence of mechanical loading and thermocycling on microleakage of class V resin-based composite restorations with and without enamel bevel. Methods and Materials Sixty class V cavity preparations measuring 3.0 mm wide (mesiogingivally) x 2.0 mm high (occluso-gingivally) x 1.5 mm deep with the occlusal margin in enamel and the gingival margin in cementum were prepared on the buccal surfaces of human premolars using a #12 diamond round bur (Drendel & Zweiling Diamant GmbH, Lemgo, Germany) in a high-speed, water-cooled handpiece. The specimens were then divided into two groups of 30 specimens each, based on the type of enamel cavosurface margin configuration as beveled or nonbeveled (butt joint). After restoring the preparations with a flowable resin-based composite (Tetric Flow, Ivoclar Vivadent-AG, Schaan, Liechtenstein) and finishing and polishing with sequential discs (Sof-Lex Pop-on, 3M-ESPE, St. Paul, MN, USA), the teeth were stored at 37°C and 100 percent humidity. Twenty-four hours later, half of the specimens in each group (nonbeveled “N” or beveled “B”) were exposed to a cycling loading for 250,000 cycles to simulate occlusal loading and assigned to two subgroups (NL+ or BL+), while the remainder of the specimens in each group were only maintained in a 100-percent-humidity environment, without any cyclical loading, until tested (NL– or BL–). The specimens were sealed with sticky wax (Kemdent, Associated Dental Products, Swindon, UK) and nail polish. The apical foramen of each tooth was sealed with sticky wax and the rest of the tooth was covered with nail varnish, except for an area within 1.0 mm around the composite restoration. To detect marginal leakage, all of the samples were stored in a 0.5 percent basic fuchsine solution for 24 hours. The specimens were then sectioned longitudinally using a low-speed diamond blade (IsoMet, Buehler Ltd., Lake Bluff, IL, USA), machined, and evaluated under 25X magnification using a stereomicroscope (M9, Wild Heerbrugg, Switzerland). The specimens were scored on a scale from 1 to 4 on the degree of dye penetration. The qualitative data were analyzed by the Mann- Whitney U test at a 5 percent significance level (p<0.05). The null hypothesis of this study was that there is no difference in microleakage between beveled and nonbeveled class V buccal preparations in premolar teeth restored with resinbased composite and subjected to simulated occlusal loading and thermocycling. Results In each group the gingival margin showed significantly more microleakage than the enamel margin (p<0.05). Load cycling did not result in an increase in microleakage in nonbeveled (p=0.259) or in beveled (p=0.053) occlusal margins. However, the gingival margins showed a statistically significant difference in microleakage after load cycling whether in cavities with enamel occlusal bevel (p=0.004) or in groups without a bevel. This means the enamel margin configuration of the enamel occlusal margin had no effect on decreasing microleakage in the gingival aspect of class V composite restorations. In general, the nonbeveled preparations in this study had significantly less microleakage than the bevel specimens whether they were loaded occlusally or not (p=0.001). Clinical Significance Within the limitations of this in vitro study, no benefit was derived from placing an enamel cavosurface bevel on the occlusal margin of a standardized class V composite restoration located at the cementoenamel junction. The most important consideration is to prevent microleakage along the gingival margin regardless of whether the occlusal enamel margin is beveled. Citation Ameri H, Ghavamnasiri M, Abdoli E. Effects of load cycling on the microleakage of beveled and nonbeveled occlusal margins in class V resin-based composite restorations. J Contemp Dent Pract [Internet]. 2010 October; 11(5):025- 032. Available from: http://www.thejcdp.com/ journal/view/volume11-issue5-ghavamnasiri


2013 ◽  
Vol 31 (15_suppl) ◽  
pp. 3600-3600
Author(s):  
Bryan K. Kee ◽  
Rebecca Slack ◽  
Todd S. Crocenzi ◽  
Lucas Wong ◽  
Benjamin Esparaz ◽  
...  

3600 Background: CASAD is a naturally occurring calcium montmorrilonite clay that serves as a cation exchange absorbent. One of the active metabolites of Irinotecan is SN-38, which is adsorbed by CASAD in vitro. The study hypothesis was that oral CASAD would reduce the rate of grade 3/4 diarrhea in mCRC patients treated with irinotecan. Methods: The study is a multicenter, prospective, randomized, double blinded placebo-controlled phase II trial. One hundred patients receiving I-based chemotherapy were randomized equally between CASAD (1000 mg po 4x daily) and placebo in order to have 75% power to detect a difference in the proportions of patients with grade 3/4 diarrhea within 6 weeks at a 1-sided 5% significance level. We also compared symptom burden using the MDASI questionnaire summed over the 13 symptom items for weeks 0, 3, 5, and 6. Results: Between 5/2009 and 5/2012, 100 patients were randomized in a 1:1 ratio between study arms. Median age 57 yrs, 54% male, 74% Non-Hispanic White, 93% performance status 0 or 1. Serious diarrhea was less frequent than expected based upon prior studies with Irinotecan. In evaluable patients, no significant difference in the rate of G3/4 diarrhea was seen (the primary endpoint): CASAD arm: 7/43 pts (16%), Placebo arm: 3/32 pts (9%), p=0.70. The rate of any diarrhea among all pts was also similar: CASAD arm 64% vs. Placebo arm 70%. The rate of study dropout was 14% in CASAD and 38% for placebo (p=0.01; 2-sided). No differences were found in symptom burden or individual symptom items or serious adverse events. Conclusions: Compared with placebo, CASAD use was safe but ineffective in preventing diarrhea in mCRC patients treated with irinotecan-containing chemotherapy regimens. There were no favorable or unfavorable signals in terms of the patient experience related to symptoms, but there were significantly more dropouts in the placebo arm. Future CASAD trials are focused on active treatment of diarrhea. Clinical trial information: NCT00748215.


2013 ◽  
Vol 18 (6) ◽  
pp. 106-111 ◽  
Author(s):  
Paulo Estevão Scanavini ◽  
Renata Pilli Jóias ◽  
Maria Helena Ferreira Vasconcelos ◽  
Marco Antonio Scanavini ◽  
Luiz Renato Paranhos

OBJECTIVE: This study assessed the anterior-posterior positioning of the upper and lower first molars, and the degree of rotation of the upper first molars in individuals with Class II, division 1, malocclusion. METHODS: Asymmetry I, an accurate device, was used to assess sixty sets of dental casts from 27 females and 33 males, aged between 12 and 21 years old, with bilateral Class II, division 1. The sagittal position of the molars was determined by positioning the casts onto the device, considering the midpalatal suture as a symmetry reference, and then measuring the distance between the mesial marginal ridge of the most distal molar and the mesial marginal ridge of its counterpart. With regard to the degree of rotation of the upper molar, the distance between landmarks on the mesial marginal ridge was measured. Chi-square test with a 5% significance level was used to verify the variation in molars position. Student's t test at 5% significance was used for statistical analysis. RESULTS: A great number of lower molars mesially positioned was registered, and the comparison between the right and left sides also demonstrated a higher number of mesially positioned molars on the right side of both arches. The average rotation of the molars was found to be 0.76 mm and 0.93 mm for the right and left sides, respectively. CONCLUSION: No statistically significant difference was detected between the mean values of molars mesialization regardless of the side and arch. Molars rotation, measured in millimeters, represented ¼ of Class II.


2018 ◽  
Vol 43 (2) ◽  
pp. 180-189 ◽  
Author(s):  
A Peutzfeldt ◽  
S Mühlebach ◽  
A Lussi ◽  
S Flury

SUMMARY The aim of this in vitro study was to investigate the marginal gap formation of a packable “regular” resin composite (Filtek Supreme XTE [3M ESPE]) and two flowable “bulk fill” resin composites (Filtek Bulk Fill [3M ESPE] and SDR [DENTSPLY DeTrey]) along the approximal margins of Class II restorations. In each of 39 extracted human molars (n=13 per resin composite), mesial and distal Class II cavities were prepared, placing the gingival margins below the cemento-enamel junction. The cavities were restored with the adhesive system OptiBond FL (Kerr) and one of the three resin composites. After restoration, each molar was cut in half in the oro-vestibular direction between the two restorations, resulting in two specimens per molar. Polyvinylsiloxane impressions were taken and “baseline” replicas were produced. The specimens were then divided into two groups: At the beginning of each month over the course of six months' tap water storage (37°C), one specimen per molar was subjected to mechanical toothbrushing, whereas the other was subjected to thermocycling. After artificial ageing, “final” replicas were produced. Baseline and final replicas were examined under the scanning electron microscope (SEM), and the SEM micrographs were used to determine the percentage of marginal gap formation in enamel or dentin. Paramarginal gaps were registered. The percentages of marginal gap formation were statistically analyzed with a nonparametric analysis of variance followed by Wilcoxon-Mann-Whitney tests and Wilcoxon signed rank tests, and all p-values were corrected with the Bonferroni-Holm adjustment for multiple testing (significance level: α=0.05). Paramarginal gaps were analyzed descriptively. In enamel, significantly lower marginal gap formation was found for Filtek Supreme XTE compared to Filtek Bulk Fill (p=0.0052) and SDR (p=0.0289), with no significant difference between Filtek Bulk Fill and SDR (p=0.4072). In dentin, significantly lower marginal gap formation was found for SDR compared to Filtek Supreme XTE (p&lt;0.0001) and Filtek Bulk Fill (p=0.0015), with no significant difference between Filtek Supreme XTE and Filtek Bulk Fill (p=0.4919). Marginal gap formation in dentin was significantly lower than in enamel (p&lt;0.0001). The percentage of restorations with paramarginal gaps varied between 0% and 85%, and for all three resin composites the percentages were markedly higher after artificial ageing. The results from this study suggest that in terms of marginal gap formation in enamel, packable resin composites may be superior to flowable “bulk fill” resin composites, while in dentin some flowable “bulk fill” resin composites may be superior to packable ones.


2022 ◽  
Vol 52 (1) ◽  
pp. E11

OBJECTIVE The application of robots in the field of pedicle screw placement has achieved great success. However, decompressive laminectomy, a step that is just as critical as pedicle screw placement, does not have a mature robot-assisted system. To address this lack, the authors designed a collaborative spine robot system to assist with laminectomy. In this study, they aimed to investigate the reliability of this novel collaborative spinal robot system and compare it with manual laminectomy (ML). METHODS Thirty in vitro porcine lumbar vertebral specimens were obtained as experimental bone specimens. Robot-assisted laminectomy (RAL) was performed on the left side of the lamina (n = 30) and ML was performed on the right side (n = 30). The time required for laminectomy on one side, whether the lamina was penetrated, and the remaining thickness of the lamina were compared between the two groups. RESULTS The time required for laminectomy on one side was longer in the RAL group than in the ML group (median 326 seconds [IQR 133 seconds] vs 108.5 seconds [IQR 43 seconds], p < 0.001). In the RAL group, complete lamina penetration occurred twice (6.7%), while in the ML group, it occurred 9 times (30%); the difference was statistically significant (p = 0.045). There was no statistically significant difference in the remaining lamina thickness between the two groups (median 1.035 mm [IQR 0.419 mm] vs 1.084 mm [IQR 0.383 mm], p = 0.842). CONCLUSIONS The results of this study confirm the safety of this novel spinal robot system for laminectomy. However, its efficiency requires further improvement.


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