Morphometric study for the localization of the mental foramen in relation to the vertical reference plane.

BACKGROUND: The mental foramen (MnF) is the anatomic landmark where the mental neurovascular bundle exits the mandible. Precisely determining the position of the MnF is necessary before all dentoalveolar therapeutic procedures performed in the mandibular premolar area. MATERIALS AND METHODS: For the study, we performed two ex vivo direct morphometric determinations on dry human dentate and edentate mandibles, and two in vivo imaging morphometric determinations through cone-beam computed tomography (CBCT) and orthopantomography (OPG) in dentate human patients. The following landmarks were used to locate the MnF: the distance between the MnF and the superior border of the mandible (MnF-SB), the distance between the MnF and the inferior border of the mandible (MnF-IB), and the position of the MnF in relation to the root apices of the posterior teeth. The results obtained from these data were processed statistically using the analysis of variance (ANOVA). RESULTS: By direct morphometry on dentate mandibles, the MnF was situated closer to the IB and by direct morphometry on completely edentulous mandibles, the MnF was located closer to the SB. In both direct morphometry studies, the MnF transverse diameter was larger than the vertical one, with the MnF having an oval shape. ANOVA for both direct morphometry studies showed that the distances MnF-IB and MnF-SB significantly vary statistically with interactions and depending on age (p<0.00001). The vertical diameter of the MnF significantly varies statistically depending on age, interactions and between studies, and its transverse diameter varies statistically significantly with interactions and depending on age (p<0.00001). According to OPG and CBCT imaging studies, the MnF was located closer to the IB, and the transverse diameter of the MnF was larger than the vertical diameter; such results are similar to the direct morphometry study performed on dry dentate human mandibles. Regarding the position of the MnF in relation to the root apices, it was most frequently located inferior to the root apices in 79.45% of cases, in 19.23% of cases it was located at the root apices level and in 1.31% of cases it was located superior (coronal) to the root apices. ANOVA for both imaging morphometry studies showed that the MnF-IB distance varies statistically significantly with the interactions, the study, the sex of the patients and their age, the MnF-SB distance varies statistically significantly with the interactions, the study and the patients' age (p<0.05), and the MnF diameters vary statistically significantly with interactions and patient age (p<0.05). CONCLUSIONS: The results of this study can help dental practitioners in improving dentoalveolar surgery procedures in the posterior mandible.

How did the COVID-19 pandemic impact the stress vulnerability of employed and non-employed nursing students in Romania?

In the light of the current COVID-19 pandemic, being considered a present challenge for public health, the main purpose of this work is to analyze the vulnerability to stress of a sample of nursing students in Romania considering their status on labour market (employed students in the medical system and non-employed students) before and during the COVID-19 pandemic. Employed students were more vulnerable to stress comparing to non-employed ones during the pandemic. In addition to this, the nursing students working in the medical system experienced medium vulnerability to stress during the pandemic comparing to those working before the pandemic who experienced a low vulnerability to stress. Excepting the non-employed students before the pandemic, the females were more vulnerable to stress comparing to the males in the sample and the students living in the country experienced a higher level of stress comparing to those living in the urban area. During the pandemic, most of the employed nursing students expressed their fear of getting infected with COVID-19, this representing the most stressful factor for them, while most of them mentioned the self-control as being the most proper strategy for them to cope with stress. These empirical findings have practical implications for stress control among present and future nurses, for management of medical units and for higher education nursing.

Factors influencing the articular eminence of the temporomandibular joint (Review).

The temporomandibular joint (TMJ), the most complex and evolved joint in humans, presents two articular surfaces: the condyle of the mandible and the articular eminence (AE) of the temporal bone. AE is the anterior root of the zygomatic process of the temporal bone and has an anterior and a posterior slope, the latter being also known as the articular surface. AE is utterly important in the biomechanics of the TMJ, as the mandibular condyle slides along the posterior slope of the AE while the mandible moves. The aim of this review was to assess significant factors influencing the inclination of the AE, especially modifications caused by aging, biological sex or edentulism. Studies have reported variations in the angles of the slopes of the AE between medieval and recent human dry skulls, as well as between subjects of different racial origin. Recent articles have emphasized the significant role that tooth loss has on the flattening of the AE. Although some papers have described biological sex or age as factors which could be associated with differences in AE angulations, edentulism seems to be a significant factor impacting on the inclination of the AE.

The Effects of COVID-19 Pandemic on Stress Vulnerability of Nursing Students According to Labour Market Status.

Nursing has always been a stressful job affecting the physical and mental health of the nurses, but the new medical context of the COVID-19 pandemic has enhanced this issue. The objective of this paper is to study differences between non-employed and employed nursing students in the medical system of Romania before and during the epidemic using matching methods and a sample of 526 nursing students. Stressors and strategies for coping with stress were also identified during the pandemic. The results indicated that employed students were more vulnerable to stress compared to non-employed ones before and during the pandemic. Females registered significantly higher stress scores compared to males in the period of the epidemic. The analysis of the overall sample suggested that gender and environment were significant stress factors during the pandemic, but living conditions were not relevant. The most effective coping strategies against stress for nurses during the COVID-19 crisis were based on self-control and the spiritual dimension, unlike the previous period when other colleagues' support helped most nurses to overcome difficult working conditions. The implications of this study might help medical management in ensuring a less stressful environment for nurses during the epidemic.

Morphometric study for determining the anteroposterior position of the mental foramen in dentate human subjects.

BACKGROUND: The mental foramen (MnF) is the place where the mental nerve and mental artery exit the body of the mandible, being an important landmark for dentoalveolar surgery. MATERIALS AND METHODS: For the assessment of MnF topography, we performed a direct morphometric study and two morphometric imaging studies through cone-beam computed tomography (CBCT) scans and orthopantomography (OPG). The following locations of the MnF were investigated: anterior to the first premolar, at the first premolar level, between the two premolars, at the second premolar level, between the second premolar and the 6-year molar, and at the level of the mesial root of the 6-year molar. The data obtained were statistically analyzed by chi-squared test. RESULTS: Through direct morphometry on dentate dry human mandibles, no statistically significant differences were found for the number of MnF located between the two premolars, at the level of the second premolar and between the second premolar and the 6-year molar, depending on age and analyzed side. The number of MnF located between the second premolar and the first molar varies statistically significantly in relation to the subject's gender but does not vary statistically significantly depending on age and side. By means of imaging morphometry through OPG, we found that the number of MnF located at the first premolar level, between the two premolars, at the second premolar level and between the second premolar and the 6-year molar varies statistically significantly in relation to the age of the patients. Using imaging morphometry trough CBCT scans, we found that the number of MnF located between the two premolars, at the second premolar level and between the second premolar and the 6-year molar varies statistically significantly according to the age of the patients. Comparing the results obtained from the three studies, we found that only according to age the number of MnF located between premolars and at the level of the second premolar varies statistically significantly. CONCLUSIONS: Wide and accurate knowledge of both the MnF topography and the key anatomical landmarks used in locating it proves to be essential and clinically relevant in dentoalveolar and endodontic surgery, and for improving anesthesia techniques.