Evaluation of occlusal force in Class II subdivision malocclusion.

BACKGROUND: Class II subdivision is a malocclusion characterized by dental and functional asymmetry that is difficult to manage. Impaired muscle function can result in asymmetrical growth, leading to occlusal instability. OBJECTIVE(S): The study aimed to assess occlusal force in patients with Class II subdivision malocclusion using Innobyte. Additionally, the discrepancies of force generated at the position of maximum intercuspidation between the left and right sides of the arches were evaluated. METHODS: The occlusal force of 66 patients with Class II subdivision malocclusion (group S) was measured and compared with that of 66 patients with Class I (group I) and 66 patients with Class II malocclusion (group II). The S group patients had a Class I molar on the right side and a Class II molar on the left side. ANOVA test, followed by the Games-Howell post hoc test, was performed to compare the mean of the total force among the groups. To assess the difference in force between the right and left arches, one-way ANOVA test followed by Tukey's post hoc comparison was performed. Finally, a boxplot was created to show the trend of occlusal force recorded in the three groups of patients. RESULTS: The occlusal force differed significantly among the groups (p < .001). Post hoc Games-Howell analysis showed significant differences as follows: the total force in group S was 165.24 N greater than in group II and in group I was 218.06 N greater than in group II. The difference (right-left) in total force between the groups was statistically significant (p < .001). Tukey's post hoc test showed following significant correlation: in group S was 53.51 N greater than in group II and 63.12 N greater than in group I. CONCLUSIONS: Among the analysed groups, patients with Class II malocclusion exhibited the lowest value of occlusal force. In patients with Class II subdivision malocclusion, force asymmetry, characterised by a higher value on the Class I side and a lower value on the Class II side was observed.

Reliabilty of recording occlusal contacts by using intraoral scanner and articulating paper - A prospective study.

OBJECTIVE: The recording of occlusal contacts is a pivotal step in many dental procedures, yet the lack of a standardized method could introduce clinical errors. The aim of this study was to compare the occlusal contacts recorded using a intraoral scanner to the contacts recorded using articulating paper. As a secondary outcome, the subjective clinical assessment made using the two methods was compared between different observers. METHODS: Twenty-eight records were analysed for this study. Digital scan and intraoral photos of the coloured marks impressed by articulating paper were taken at the same time point for every patient. Using a standardized occlusal template, two operators recorded the number of occlusal contacts for every tooth provided by the two techniques. Then, 11 clinicians analysed the collected records and answered questions about the quality of the occlusions observed. RESULTS: The statistical analysis showed significant differences between the number of contacts recorded by digital scan and those recorded by the photographed articulation marks, except in the case of the upper central incisors and first premolars. The Kappa Fleiss showed slight and fair agreement between clinicians when judging the occlusions. CONCLUSION: The occlusal contacts recorded using the intraoral scanner and those recorded with the articulating paper did not match, and overall the clinicians showed low agreement when rating the recorded data. CLINICAL SIGNIFICANCE: Despite of the great clinical importance of occlusal contact there is a lack of a precise method for recording and collecting occlusal contacts.

Skeletal and dental effects of function-generating bite appliance compared to rapid palatal expander and untreated controls.

INTRODUCTION: Maxillary expansion is a fundamental interceptive orthodontic treatment, which can be achieved through either a rapid expansion protocol or functional devices. However, no data exist about the efficacy of functional devices in achieving skeletal expansion. Therefore, the aim of this study was to compare the effects of the rapid palatal expander (RPE) and the function-generating bite type M (FGB-M) on the transversal dimension of the maxilla, and on the maxillary and mandibular dental arch width. METHODS: One hundred eighty-one skeletal Class I patients, aged between 6 and 12 years and with a cervical vertebral maturation stage II or III, with maxillary transversal deficiency were retrospectively enrolled; among these 55 were treated with FGB-M, 73 were treated with RPE and 51 were untreated subjects retrieved from historical databases. The pre-treatment (T0) and post-treatment (T1) frontal cephalograms were retrieved, and the maxillary and mandibular widths, and the distance between upper and lower first molars were measured. T1-T0 interval was of 17.3 months (RPE), 24.6 months (FGB-M) and 18.2 months (controls). RESULTS: The statistical analysis showed that there were no statistically significant differences between the RPE and FGB-M groups regarding skeletal and dental expansion, while the untreated control group differed significantly from the other two groups. CONCLUSION: The comparison between patients treated with RPE and FGB-M showed that there were no statistically significant differences between the RPE and FGB-M groups regarding the amount of skeletal expansion and dental arch width, suggesting that both appliances can be used to achieve similar results.

Evaluation of the relationship between incisor torque and profile aesthetics in patients having orthodontic extractions compared to non-extractions.

OBJECTIVE: The aim of the present study was to evaluate the relationship between soft tissues aesthetics and incisor torque, as well as the effect of crowding, anchorage, and extraction pattern, in adult patients treated without extraction or with two or four extractions. MATERIALS AND METHODS: Seventy-seven subjects with permanent dentition were selected retrospectively. Among these, 24 patients were treated with four extractions, 24 with two extractions and 29 without extractions. Lateral cephalograms and photographies taken before (T0) and after (T1) treatment were retrieved. The amount of crowding and the type of anchorage were recorded, and a cephalometric analysis was performed. A one-way ANOVA was used to compare the variables within and between groups. Linear regressions were performed to evaluate the effect of different predictors on soft tissues variables at T1. RESULTS: The statistical analysis showed no differences within and between groups for soft tissue aesthetics. A significant reduction of the angle obtained from the intersection of Frankfurt plane and mandibular plane was observed in the four-extractions group, and a significant proclination of the lower incisors was observed in the two-extraction group. Linear regressions revealed that the change in soft tissue profile aesthetics was affected by the type of anchorage and the two-extractions pattern. CONCLUSIONS: Similar soft tissue aesthetics were observed after treatment in the three groups, despite the presence of some skeletal and dental differences. CLINICAL RELEVANCE: A well-controlled incisor torque helps to preserve soft tissues aesthetics. The type of anchorage could influence soft tissues.

Changes in hyoid bone and tongue position in Class I subjects after orthodontic treatment with rapid palatal expander.

OBJECTIVE: To evaluate the effects of the rapid palatal expander (RPE) on the hyoid bone and tongue position in skeletal Class I patients, compared to control groups. METHODS: Eighty-four Class I subjects, aged 6-14, were selected. Among these, 28 patients were treated with RPE, 28 with function-generating bite (FGB) appliance, and 28 were untreated. Lateral cephalograms taken before (T0) and after (T1) treatment were retrieved. Changes in the hyoid bone and tongue position were evaluated, and the area above the tongue was measured. RESULTS: No significant difference in the hyoid and tongue posture was observed across the groups. However, there were significant differences for HC3 (distance from H-point to the third cervical vertebrae), H2H (distance from H-point to SN plane), and TT-Eb (tongue length) between T0 and T1 in all groups. CONCLUSION: The results suggest that hyoid bone and tongue position changes were related to growth rather than treatment.

Discovery of the Involvement in DNA Oxidative Damage of Human Sperm Nuclear Basic Proteins of Healthy Young Men Living in Polluted Areas.

DNA oxidative damage is one of the main concerns being implicated in severe cell alterations, promoting different types of human disorders and diseases. For their characteristics, male gametes are the most sensitive cells to the accumulation of damaged DNA. We have recently reported the relevance of arginine residues in the Cu(II)-induced DNA breakage of sperm H1 histones. In this work, we have extended our previous findings investigating the involvement of human sperm nuclear basic proteins on DNA oxidative damage in healthy males presenting copper and chromium excess in their semen. We found in 84% of those males an altered protamines/histones ratio and a different DNA binding mode even for those presenting a canonical protamines/histones ratio. Furthermore, all the sperm nuclear basic proteins from these samples that resulted were involved in DNA oxidative damage, supporting the idea that these proteins could promote the Fenton reaction in DNA proximity by increasing the availability of these metals near the binding surface of DNA. In conclusion, our study reveals a new and unexpected behavior of human sperm nuclear basic proteins in oxidative DNA damage, providing new insights for understanding the mechanisms related to processes in which oxidative DNA damage is implicated.

Pervasive developmental disorders in children of hyperandrogenic women with polycystic ovary syndrome: a longitudinal case-control study.

OBJECTIVE: Foetal exposure to high testosterone concentrations seems to be involved in the development of mammalian brain and related to pervasive developmental disorders (PDDs). The aim of the current study was to test the hypothesis that children born from hyperandrogenic women with polycystic ovary syndrome (PCOS) are at higher risk of PDDs. DESIGN: Longitudinal case-control study. PATIENTS: Thirty pregnant PCOS patients with hyperandrogenaemia and other 45 pregnant healthy women were followed during pregnancy. All women had a healthy baby. MEASUREMENTS: Clinical evaluations and biochemical assays of the mothers during pregnancy and after delivery were performed. The children's versions of the Autism-Spectrum Quotient (AQ-C), the Empathy Quotient (EQ-C) and Systemizing Quotient (SQ-C) tests were administered. RESULTS: Total AQ-C and communication scores were significantly higher for children of PCOS patients. Stratifying our population according to sex, total AQ-C, communication and attention switching subscores were significantly higher only for daughters of PCOS patients. EQ-C and SQ-C scores resulted in significantly lower and higher scores, respectively, only in daughters of PCOS patients in comparison with those of healthy non-PCOS controls. AQ-C, EQ-C and SQ-C scores, irrespective of the studied group and/or subclassification by gender, were significantly influenced by amniotic testosterone levels. CONCLUSIONS: Daughters of mothers affected by hyperandrogenic PCOS seem to have a higher risk for PDDs probably due to an unbalanced prenatal exposure to high levels of testosterone.