Correlation of Mandibular Second Molar Impaction with Third Molar Size, Angulation, Developmental Stage, and Bud Position

Objective: The present study assessed the association of size, axial angulation, developmental stage and bud position of the mandibular third molar with the second molar impaction in patients with mandibular second molar impaction.Methods: In this descriptive-analytical study (Case-Control Design), dental records of 5,420 patients in the age range of 12-15 years who underwent orthodontic treatment were assessed out of which 20 patients (14 females and 6 males) with lower second molar impaction were studied. Twenty control patients with erupted second molars were selected from the same centers and matched with the case group. Total sample size was 40 (Case and Control) and had normal distribution for the determined measurements. Third molar axial angulation towards the second molar, first molar and mandibular base, mesiodistal width of 3rd molar /2nd molar ratio, Nolla developmental stage and third molar bud position were measured and calculated in patients with impacted and erupted second molars and analyzed using student t and chi-square tests.Results: The mean degree of third molar angulation towards the second molar, first molar and mandibular base was 30.20, 53.6, and 51.3 degrees in cases and 21.4, 34.65 and 45.15 degrees in controls, respectively. Significant differences were found between the two groups in terms of third molar angulation towards the second molar (30.2 Vs 21.4 degrees p<0.047), and first molar (53.6 Vs34.65 degrees p<0.0001); while no differences were found between the two groups in terms of third molar angulation towards the mandibular base (51.3 Vs 45.15 degrees). The mean mesiodistal width of third molar/ second molar ratio was 0.99 in cases and 0.95 in controls with no significant difference. Nolla developmental stage and position of the marginal ridge of the third molar bud towards the second molar showed no definite relation with second molar impaction.Conclusion: It seems that angulation of third molar to the second and first molars is a major contributing factor to increase the risk of second molar impaction. Third molars size, developmental stages, and bud positions, do not show a significant relation to the second molar impaction

Comparison of the Chemical Compositions and Antibacterial Activities of Two Iranian Mustard Essential Oils and Use of these Oils in Turkey Meats as Preservatives

Background and objective: Iranian mustard is cultivated in southern areas of Iran and used traditionally as natural preservative. Aims of the current study were identification and comparison of the chemical compositions and antibacterial activities of two Iranian mustard essential oils and assessment of these oils use for increasing the shelf life of turkey meats.Material and methods: Chemical compositions of two Iranian mustard essential oils were identified using gas chromatography-mass spectrometry and antibacterial activities of these oils were assessed against Salmonella typhimurium, Escherichia coli, Citrobacter freundii, Pseudomonas aeruginosa, Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus and Enterococcus faecalis using disc diffusion and broth macrodilution assays. Inhibitory effects of the essential oils were assessed on growth of mesophilic psychrotrophic bacteria, yeasts and molds and sensory evaluation was carried out for the turkey meats.Results and conclusion: Results of GC-MS showed presence of bioactive constituents, especially allyl isothiocyanate (75.87-80.07%). All the bacterial growth, especially for Escherichia coli, was inhibited with inhibition zones of greater than 20 mm and minimum inhibitory and bactericidal concentrations of 0.156 mg ml-1. Treatment of turkey meat samples with the mustard essential oils significantly decreased the count of mesophilic psychrotrophic bacteria, yeasts and molds during 20 days of storage at 4°C ±1, compared to controls (P≤0.05). Over the time, the sensory score of the treated samples increased, compared to controls. Based on these findings, the Iranian mustard essential oils can be used as natural preservatives in foods.Conflict of interest: The authors declare no conflict of interest

Thriving in management innovation: an institutional perspective

Purpose: Management innovation is one of the most vital practices underpinning economic growth and is considered to be one of the fundamental components of gaining a superior business position in market conditions that are continually fluctuating. Drawing upon neo-institutional theory as well as absorptive capacity, the current empirical study unpacks the relationships between external institutional forces (i.e. regulative, mimetic and normative pressures) and management innovation through investigating the role of absorptive capacity as a mediator. Design/methodology/approach: The research model is tested using survey data from Australian organisations. The study used Partial Least Squares (PLS), a component-based structural equation modelling (SEM) method, in order to perform the data analysis. Findings: The results confirm that the various dimensions of institutional forces have diverse influences on management innovation. The authors found mimetic and normative pressures have positive influences on realised and potential absorptive capacity of an organisation. In addition, realised absorptive capacity mediates the relations between institutional forces and management innovation. Originality/value: Dissimilar to preceding studies, this research shows that organisations not only innovate to pursue higher performance but sometimes strive for legitimacy. In addition, the significant associations between absorptive capacity and management innovation and the mediation role clearly signify that institutional forces and absorptive capacity play significant roles in the adoption of management innovation.</p