The prevalence of malocclusion among 7–15-year-old Lithuanian schoolchildren

The epidemiological data on the prevalence of malocclusion is an important determinant in planning appropriate levels of orthodontic services. The occurrence of occlusal anomalies varies between different countries, ethnic and age groups. The aim of this study was to describe the prevalence of malocclusion among Lithuanian schoolchildren in the 7–9-, 10– 12-, and 13–15-year age groups assessing occlusal morphology. The study included 1681 schoolchildren aged 7–15 years. The crowding, spacing, overbite, overjet, the relationship of the first upper and lower molars according Angle’s classification, and posterior crossbite were assessed. The study demonstrated that only 257 children had normal occlusion, and 44 had undergone orthodontic treatment among them. The greatest overjet in the studied contingent was 11 mm, and the negative overjet – 3 mm. The overbite ranged between 0 and 6 mm with a mean of 2.29±1.23 mm. Posterior crossbite was recorded in 148 children (8.8%). This study showed that the prevalence of malocclusion among 7–15-year-old Lithuanian schoolchildren is 84.6%. The most common malocclusion was dental crowding. The upper dental arch crowding was registered for 44.1% and lower for 40.3% of all schoolchildren. The class I molar relationship was detected in 68.4% of the subjects, class II – in 27.7%, and class III – in 2.8%

Effect of Genetic and Environmental Factors on the Impaction of Lower Third Molars

The aim of this retrospective study was to evaluate the impact of genetic and environmental factors on the impaction of lower third molars using a classical twin study by evaluation of the third molar eruption space and M3 angulation. The study group consisted of 212 twins: 80 dizygotic and 132 monozygotic twins with digital panoramic radiograms and lateral cephalograms. The zygosity of twins was determined using 15 highly polymorphic DNA regions from the venous blood of twins. The results showed that differences between siblings in the dizygotic and monozygotic twin pairs were not statistically significant. The most fitting model for the angulations of lower third molars was AE (additive genetic and specific environmental effect), where the additive genetic factors had up to 88% influence and the specific environment up to 27%. Therefore, the ACE( additive genetic, common and specific environmental effect), model showed higher significance for the lower third molar eruption level where additive genetic estimates reached 71%, a specific environment contributed up to 15% and the common environment reached 32%. The conclusion was that a considerable proportion of the third molar impaction could be attributed to additive genetic effects and the common environment, whereas the specific environment had a lower, but significant impact

Factors Affecting Self-Eruption of Displaced Permanent Maxillary Canines

The aim of this study was to examine the possibility of the spontaneous eruption of displaced unerupted maxillary canines after the extraction of the deciduous canine and dental arch expansion and to determine the impact of initial canine position on treatment success rate. Materials and Methods. The study sample included 50 patients (mean age, 13.5 years [SD, 2.2]) with unilaterally displaced unerupted maxillary canines. Deciduous canines were extracted, and the space for displaced canine was created at the beginning of the study. The follow-up period for the spontaneous eruption was 12 months. The initial vertical, horizontal, labio-palatal position and angle of inclination to the midline of the displaced canine were assessed on panoramic radiographs. Results. Only 42% of displaced canines erupted spontaneously within one-year period (52.9% of labially displaced canines and 36.4% of palatally displaced canines). A significant difference of inclination was determined between spontaneously erupted and unerupted teeth in the labially displaced canine group (P<0.01), with no difference in the palatally displaced canine group. The receiver operating characteristic curve analysis showed that the critical angle of inclination for the spontaneous eruption of the retained canine was 20º (sensitivity 0.759; specificity 0.571; P<0.05). The majority of unerupted canines (75.9%) were inclined more than 20º. The initial height of canine was crucial for spontaneous eruption (sensitivity 0.966; specificity 0.81; P<0.001). This was true for both palatal and labial cases. Conclusions. The initial vertical position of the labially and palatally displaced canines and the inclination of the labially displaced canines were the most important predictors for spontaneous eruption of the cuspid

Associations of short-term exposure to ambient air pollutants with emergency ambulance calls for the exacerbation of essential arterial hypertension

ISSN 1369-1619 (Online)We investigated the association between daily emergency ambulance calls (EAC) for elevated blood pressure that occurred during the time intervals of 8:00–13:59, 14:00–21:59, and 22:00–7:59, and exposure to CO, PM10, and ozone. We used Poisson regression to explore the association between the risk of EAC and short-term variation of pollutants, adjusting for seasonality and weather variables. Before noon, the risk was associated with an interquartile range (IQR) (7.9 μg/m3) increase in PM10 at lag 2–4 days below the median (RR = 1.08, p = 0.031) and with an IQR (0.146 mg/m3) increase in CO at lag 6–7 below the median (RR = 1.05, p = 0.028). During 14:00–21:59, the risk was associated with an IQR (18.8 μg/m3) increase in PM10 on the previous day below the median (RR = 1.04, p = 0.031). At night, EAC were negatively affected by lower O3 (lag 0–2) below the median (per IQR decrease RR = 1.10, p = 0.018) and a higher PM10 at lag 0–1 above the median for the elderly (RR = 1.07, p = 0.030)Aplinkotyros katedraGamtos mokslų fakultetasLietuvos sveikatos mokslų universitetas. Medicinos akademijaVytauto Didžiojo universiteta

Relationship between Craniocervical Posture and Sagittal Position of the Mandible: A Systematic Review

Changes in craniocervical posture are a critical issue in modern society. Alterations of the mandible position in the anterior-posterior direction in association with head and neck posture are reported. The objective of the present review was to evaluate the relationship between craniocervical posture and sagittal position of the mandible and to evaluate the risk of bias inthe included studies. Electronic databases used to perform the search were PubMed, Wiley Online Library, and Cochrane. Only clinical trials that assessed sagittal craniocervical posture and mandible position in lateral cephalograms were included. Selected inclusion criteria were used to assess the finally selected studies. The upper and lower cervical spine was evaluated by seven and six studies, respectively. The risk of bias in the included studies varied from low to moderate. Literature research identified 438 records from 3 databases. Eventually, seven eligible clinical trials were included in this review. Evaluating the relationship between craniocervical posture and mandible position in the sagittal plane, it can be concluded that increased cervical inclination and head upright position are associated with the posterior position of the mandible. Attention to patients’ craniocervical posture should be paid as a part of clinical evaluation since it might be the reason for the changed mandible position

Heritability of cephalometric variables of airway morphology in twins with completed active growth

Abstract Background The interplay between genetic and environmental impacts on dental and facial morphology has been widely analyzed, but little is known about their relative contributions to airway morphology. The aim of this study was to evaluate the genetic and environmental influences on the cephalometric variables of airway morphology in a group of postpubertal twins with completed craniofacial growth. Materials and methods The materials comprised lateral head cephalograms of 94 pairs of twins (50 monozygotic, 44 dizygotic) with completed craniofacial growth. Zygosity was determined using 15 specific DNA markers. The computerized cephalometric analysis included 22 craniofacial, hyoideal, pharyngeal structural linear and angular variables. Genetic analysis and heritability estimation were performed using maximum likelihood genetic structural equation modeling (GSEM). Principal component analysis (PCA) was used to assess the correlations between cephalometric measurement variables. Results Upper airway dimensions showed moderate to high genetic determination (SPPW-SPP and U-MPW: a2 = 0.64 and 0.5, respectively). Lower airway parameters showed only common and specific environmental determination (PPW-TPP a2 = 0.24, e2 = 0.38; LPW-V c2 = 0.2, e2 = 0.63; PCV-AH c2 = 0.47, e2 = 0.28). The relationship between the maxilla and the hyoid bone (for variables PNS-AH, ANS-AH d2 = 0.9, 0.92, respectively) showed very strong additive genetic determination. The size of the soft palate was affected by additive and dominant genes. Its length (SPL) was strongly influenced by dominant genes, while its width (SPW) showed a moderate additive genetic influence. Owing to correlations in the behavior of variables, the data could be expressed in 5 principal components that jointly explained 36.8% of the total variance. Conclusions The dimensions of the upper airway are strongly determined by genes, while the parameters of the lower airway depend mainly on environmental factors. Trial registration The protocol has been approved by the Kaunas Regional Ethical Committee (No. BE – 2–41., May 13, 2020)

Relationship between malocclusion, soft tissue profile, and pharyngeal airways: A cephalometric study

Background and objective: The recent years have been marked by a search for new interrelations between the respiratory function and the risk of the development of malocclusions, and algorithms of early diagnostics and treatment have been developed. The aim of the study was to evaluate the relationships between hard and soft tissues and upper airway morphology in patients with normal sagittal occlusion and Angle Class II malocclusion according to gender. Materials and methods: After the evaluation of clinical and radiological data, 114 pre-orthodontic patients with normal or increased ANB angle, were randomly selected for the study. The cephalometric analysis was done by using the Dolphin Imaging 11.8 computer software. Results: Comparison of the cephalometric values of soft tissue and airway measurements performed statistically significant negative correlation between the width of the upper pharynx and the ANB angle was found: the ANB angle was decreasing with an increasing width of the upper pharynx. The airways showed a statistically significant negative correlation between the width of the lower pharynx and the distance from the upper and the lower lips to the E line. Logistic regression analysis was performed to evaluate significant factors that could predict airway constriction. The upper pharynx was influenced by the following risk factors: a decrease in the SNB angle, an increase in the nose tip angle, and younger age; while the lower pharynx was influenced by an increase in the distance between the upper lip and the E line and by an increase in the upper lip thickness. Conclusions: During critical period of growth and development of the maxillofacial system, the patients with oral functional disturbances should be monitored and treated by a multidisciplinary team consisting of a dentist, an orthodontist, a pediatrician, an ENT specialist, and an allergologist. Cephalometric analysis applied in our study showed that Angle Class II patients with significantly decreased facial convexity angle, increased nasomental, upper lip-chin, and lower lip-chin angles, and upper and lower lips located more proximally to the E line more frequently had constricted airways

Effects of weather and heliophysical conditions on emergency ambulance calls for elevated arterial blood pressure

We hypothesized that weather and space weather conditions were associated with the exacerbation of essential hypertension. The study was conducted during 2009–2010 in the city of Kaunas, Lithuania. We analyzed 13,475 cards from emergency ambulance calls (EACs), in which the conditions for the emergency calls were made coded I.10–I.15. The Kaunas Weather Station provided daily records of air temperature (T), wind speed (WS), relative humidity, and barometric pressure (BP). We evaluated the associations between daily weather variables and daily number of EACs by applying a multivariate Poisson regression. Unfavorable heliophysical conditions (two days after the active-stormy geomagnetic field or the days with solar WS > 600 km/s) increased the daily number of elevated arterial blood pressure (EABP) by 12% (RR = 1.12; 95% confidence interval (CI) 1.04–1.21); and WS ≥ 3.5 knots during days of T < 1.5 °C and T ≥ 12.5 °C by 8% (RR = 1.08; CI 1.04–1.12). An increase of T by 10 °C and an elevation of BP two days after by 10 hPa were associated with a decrease in RR by 3%. An additional effect of T was detected during days of T ≥ 17.5 °C only in females. Women and patients with grade III arterial hypertension at the time of the ambulance call were more sensitive to weather conditions. These results may help in the understanding of the population’s sensitivity to different weather conditionsAplinkotyros katedraKauno miesto greitosios medicinos pagalbos stotisLietuvos sveikatos mokslų universitetasVytauto Didžiojo universiteta

The short-term associations of weather and air pollution with emergency ambulance calls for paroxysmal atrial fibrillation

ISSN 1614-7499 (Electronic). WOS:000402997700042A circadian variation in the cardiovascular parameters has been detected. It is plausible that the influence of the environment varies during different periods of the day. We investigated the association between daily emergency ambulance calls (EC) for paroxysmal atrial fibrillation (AF) that occurred during the time intervals of 8:00-13:59, 14:00-21:59, and 22:00-7:59, and weather conditions and exposure to CO and PM10. We used Poisson regression to explore the association between the risk of EC for AF and environmental variables, adjusting for seasonal variation. Before noon, the risk was associated with an IQR (0.333 mg/m3) increase in CO at lag 2-6 days above the median (RR = 1.15, P = 0.002); a protective impact of CO on previous day was observed (RR = 0.91, P = 0.018). During 14:00-21:59, a negative effect of air temperature below 1.9 °C (lag 2-3 days) was detected (per 10 °C decrease: RR = 1.17, P = 0.044). At night, the elevated risk was associated with wind speed above the median (lag 2-4 days) (per 1-kt increase: RR = 1.07, P = 0.001) and with PM10 at lag 2-5 days below the median (per IQR (7.31 μg/m3) increase: RR = 1.21, P = 0.002). Individuals over 65 years of age were more sensitive to air pollution, especially at night (CO lag 2-3 days < median, per IQR (0.12 mg/m3) increase: RR = 1.14, P = 0.045; PM10 lag 2-5 days < median, per IQR increase: RR = 1.32, P = 0.001). The associations of air pollution and other environmental variables with acute events may be analyzed depending on the time of the eventAplinkotyros katedraLietuvos sveikatos mokslų universitetas. Medicinos akademijaVytauto Didžiojo universiteta

The effect of the teeth bleaching with 35% hydrogen peroxide on the tensile bond strength of metal brackets

The objective of this study was to determine the effects of teeth bleaching on the tensile bond strength of metal brackets bonded with light-curing adhesive system to the human enamel. 40 recently extracted human permanent molars were used for the study. The mesial buccal surface of each tooth was used as a control group and the distal buccal surface was used as an experimental group. Control group surfaces were not submitted to bleaching, while experimental group surfaces were bleached with in-office bleaching material containing 35% hydrogen peroxide. 30 days after the bleaching, identical premolar metal brackets were bonded to each surface using light-curing adhesive. Both groups were submitted to a tension test, using a universal machine. The tensile bond strength of brackets bonded to the bleached enamel was 15% lower than that of brackets bonded to the unbleached enamel. After debonding, more adhesive was left on the bracket base in experimental group than in the control group. The conclusion of this study was that bleaching with an in-office bleaching material containing 35% hydrogen peroxide reduced the tensile bond strength of orthodontic bracket adhesive to the enamel surface