Iva Alajbeg

Comparison of the composition of some petroleum samples which may be applied for skin and mucous membrane treatment

A particular Croatian petroleum (sample P1) and its three derivatives (samples P2, P3 and P4), potentially applied as healing preparations for skin and mucous membrane treatment, were studied in order to learn their composition and to discriminate them according to two criteria: composition of natural petroleum compounds, and lacking aromatics. Elemental (C, H, N and S) and group composition (by LC, UV/VIS, IR and 1H NMR) were determined and the single component distributions were analyzed (by GC) and identified (by GC-MS). Focussed saturated compounds (n-alkanes, pristane and phytane, drimanes/eudesmanes, steranes and hopanes) were studied in order to emphasize the preservation or destruction of genuine petroleum structures in derivatives. Samples P2 (petroleum-brownish color, petroleum like smell) and P3 (colorless, transparent, slight pine-like odor), were found, now constituting petroleum, to still be composed of the components of their native structure. Compared to sample P1, they were missing light and heavy compounds. While sample P2 contained different compound classes, sample P3 comprised exclusively saturated hydrocarbons, satisfying pharmacopoeias requirement regarding the low aromatics content. Almost a half of sample P3 was composed of cyclic moieties, including terpenoids, possibly responsible for the odor. Samples P1, P2 and P3 were found rather rich in steranes. Sample P4 (colorless, transparent, no smell) was found denaturalized. In spite of high similarity in bulk properties to sample P3, it comprised no detectable amount of n-alkanes, pristane and phytane, or drimanes/eudesmanes, steranes and hopanes (although found rich in oligocycles).

Measurements of the sagittal condylar inclination: intraindividual variations

Abstract Aims: Sagittal condylar inclination is an important parameter during fabrication of prosthetic restorations. Existing data about intraindividual variations of sagittal condylar inclination are scarce. The purpose of this study was to investigate intra- and interindividual variations of the sagittal condylar inclination, depending on the position of the condyle in the temporomandibular joint. Methodology: The study included 51 subjects with Angle’s Class I occlusion (21–32 years of age, mean 25·1). Measurements were done using an electronic axiograph. After a paraocclusal tray was fixed in the mouth, every subject had to make three protrusive movements, from which the device’s software calculated the mean left and mean right sagittal condylar path. The mean left and right condylar path of each subject was divided into three equal sequences, based on whole condylar path length. Condylar inclination values for the first, second and third movement sequences were calculated. Results: Results showed significant differences between movement sequences (P<0·05). For the left joint, condylar inclination values in the first condylar movement sequence demonstrated, on the average, 14·4% higher values compared to the second movement sequence, and 39·2% higher values than in the third movement sequence. For the right joint, the first condylar movement sequence demonstrated, on the average, 15·8% higher values compared to the second movement sequence, and 41·5% higher values than the third movement sequence. Conclusions: Results suggest that condylar movement in the sagittal direction is not uniform. Mean left and mean right condylar inclination values do not necessarily describe the actual condylar path, nor do they give adequate information for articulator setup. Left–right side condylar inclination differences greater than 10° can be considered as normal.

In vivo i in vitro procjena ponovljivosti i preciznosti uređaja za određivanje boje zuba VITA Easyshade® Advance 4.0

OBJECTIVES The objective of this study was to evaluate the intra-device repeatability and accuracy of dental shade-matching device (VITA Easyshade® Advance 4.0) using both in vitro and in vivo models. MATERIALS AND METHODS For the repeatability assessment, the in vivo model utilized shade-matching device to measure the central region of the labial surface of right maxillary central incisors of 10 people twice. The following tooth colors were measured: B1, A1, A2, A3, C1 and C3. The in vitro model included the same six Vitapan Classical tabs. Two measurements were made of the central region of each shade tab. For the accuracy assessment, each shade tab from 3 Vitapan Classical shade guides was measured once. CIE L*a*b* values were determined. Intraclass correlation coefficients (ICCs) were used to analyze the in vitro and in vivo intra-device repeatability of the shade-matching device. The difference between in vitro and in vivo models was analyzed. Accuracy of the device tested was calculated. RESULTS The mean color differences for in vivo and in vitro models were 3.51 and 1.25 E units, respectively. The device repeatability ICCs for in vivo measurements ranged from 0.858 to 0.971 and for in vitro from 0.992 to 0.994. Accuracy of the device tested was 93.75%. CONCLUSION Within the limitations of the experiment, VITA Easyshade®Advance 4.0 dental shade-matching device enabled reliable and accurate measurement. It can be a valuable tool for the determination of tooth colours.

Comparison of Amitriptyline with Stabilization Splint and Placebo in Chronic TMD Patients: a Pilot Study

Objective of work The authors conducted a clinical study to evaluate the effectiveness of amitriptyline in treatment of chronic TMD patients and to compare treatment results with stabilization splint. Materials and Methods Twenty-one patients with chronic TMD were included and randomly distributed into 3 groups: patients in Group A received amitriptyline, patients in Group B received placebo, and those in Group C were treated with stabilization splint. Treatment outcomes (pain assessed by a visual analogue scale (VAS), maximal comfortable mouth opening (MCO) and oral health related quality of life (OHIP-14)) were taken at baseline (before treatment), and at 1st, 6th and 12th week of treatment. Results No statistically significant differences between the groups at baseline were found (p>0.05). VAS scores improved significantly in Group A (F=11.326, p=0.002, effect size =0.791) and in group C (F=7.343, p=0.005, effect size=0.647). Mean OHIP-14 scores decreased significantly only in Group A (F=4.417, p=0.036, effect size =0.596). In Group B, VAS and OHIP-14 scores did not change significantly over time. Subjects in Group C had a significant change in MCO relative to Group A and Group B. Conclusion From this pilot study it can be concluded that the use of low doses of amitriptyline for a period of 12 weeks is effective for pain management and quality of life improvement in chronic TMD patients. Stabilization splint demonstrated superiority in the management of limited mouth opening during the same period.

In Vivo Evaluations of Inter-Observer Reliability Using VITA Easyshade® Advance 4.0 Dental Shade-Matching Device

OBJECTIVES The aim of this study was to evaluate the inter-observer reliability of dental shade-matching device using an in vivo model. MATERIALS AND METHODS Four observers who were well trained in color assessment and handling of the dental shade-matching device determined teeth color and CIE-Lab values on maxillary right central incisors in 10 patients with completely healthy and intact dentitions. VITA Easyshade® Advance 4.0 shade-matching device was utilized to measure the central region of the labial surface of all investigated teeth, twice by each observer. The inter-observer reliability of the measurements was observed and deviations between Lab and [Formula: see text]E values between the observers were calculated. Intraclass correlation coefficients (ICCs) were used to analyze inter-observer reliability. RESULTS One-way ANOVA showed no statistically significant differences in color measurement of four observers in all the measured values (p>0.05). Delta E values ranged from 3.018 to 5.234. Although some small differences existed, statistically significant differences between the observers were not found (p>0.05). Inter-observer ICCs were very high for all observers (from 0.651 to 0.992). CONCLUSION Inter-examiner reliability of measurements using VITA Easyshade® Advance 4.0 shade-matching device was acceptable. Apart from the digital equipment, a well trained observer seems to be crucial in order to achieve correct dental color measurement.