Maria Gołębiewska

The influence of the occlusal vertical dimension on masticatory muscle activities and hyoid bone position in complete denture wearers.

PURPOSE Long lasting usage of complete dentures causes lower occlusal vertical dimension, producing potential detrimental consequences. The aim of this study was to investigate how changes in vertical dimension during denture exchange affect muscular activity and hyoid bone position. MATERIAL AND METHODS Twenty-five edentulous, otherwise healthy patients (14 females, 11 males) aged 70.5 +/- 9 years, wearing their dentures over 5 years but no longer than 15 years (mean 9.8 +/- 5.2), were studied. New dentures were fabricated and the occlusal vertical dimension was recorded on cephalometric radiographs. Cephalograms were analyzed according to Ricketts. The relation of the hyoid bone position to the mandible was estimated. An evaluation of muscular activity was performed using the Biopak Electromyography Recording System synchronized with the T-Scan II Occlusal Analysis System. RESULTS The occlusal vertical dimension was higher with the new dentures compared with the old dentures. The transition to new dentures was accompanied by a change of the vertical position of the hyoid bone. Digastric muscle activity was lower with the new dentures in comparison with the old dentures. CONCLUSIONS Increase of the occlusal vertical dimension in complete denture wearers affects the hyoid bone position and masticatory muscle activity.

Enamel mineral content in patients with severe tooth wear.

PURPOSE The amounts of calcium (Ca), magnesium (Mg), zinc (Zn), and copper (Cu) in enamel may be crucial for maintaining its integrity and to attenuate potential environmental effects on teeth. The aim of this study was to examine whether the mineral composition of enamel could influence tooth wear. MATERIALS AND METHODS A total of 50 patients with severe tooth wear were compared with 20 healthy volunteers. Tooth wear was assessed using clinical examination according to the protocol of Smith and Knight. Subsequently, the maxillary central incisors of each subject were subjected to acid biopsies to assess the mineral composition in the enamel. Atomic absorption spectroscopy with an air/acetylene flame was used to analyze for Ca, Zn, and Mg. Graphite furnace atomic absorption spectroscopy was used to analyze for Cu. RESULTS The concentrations of Ca and Mg in tooth enamel were comparable in the study and control groups. Zn enamel content was higher in patients with tooth wear, and Cu enamel content was lower in these patients compared with the control group. CONCLUSION The differing Zn and Cu contents in tooth enamel might offer a reason for excessive tooth wear in these patients. However, the results require further, more detailed study.

Morphological and Functional Parameters in Patients with Tooth Wear before and after Treatment

Advanced tooth wear often results in lost vertical dimension and impacts facial aesthetics. Complex restorative treatment can replace the lost tooth structure and improve functional occlusal and facial skeleton parameters. Purpose: The aim of the study is to assess changes in the morphological and functional occlusal parameters of the facial skeleton after prosthetic rehabilitation that increased lost occlusal vertical dimension. Material and Methodology: 50 patients with advanced tooth wear were clinically examined, to assess the degree of wear. Each subject underwent cephalometric analysis, digital occlusal analysis, and electromyographic analysis, of the anterior temporalis, superficial masetter, anterior digastric, and the sternocleidomastoid muscles. Prosthodontic treatment was performed to restore the occlusal vertical dimension of each subject’s occlusion, which was followed by repeating the pretreatment analyses. Pre and post treatment parameters were statistically compared. Results: Pre-treatment cephalometric analysis showed that lost vertical dimension reduced anterior facial height and resulted in small angular skeletal parameters. Post treatment anterior facial height increased from the increased occlusal vertical dimension. The mean value of functional electrical activity during clenching post treatment, increased compared to pretreatment. Conclusion: Increasing the vertical dimension of occlusion improved facial aesthetics by positively affecting facial skeletal angles. The restored occlusal surface morphology changed the pre treatment flat broad occlusal contacts into more point contacts. The increased vertical dimension of occlusion after treatment also increased muscle activity levels over the pretreatment levels after three months period of adaptation.

Assessment of masticatory muscle activity and occlusion time in patients with advanced tooth wear

OBJECTIVE Tooth wear is a basic physiological adjustment mechanism in the masticatory system. Unfortunately, it is not clear what the relationship is between the activity of the masticatory muscles and the tooth hard tissue loss (mainly enamel) in patients with advanced tooth wear. The aims of this study were (1) to compare the occlusion times and (2) to compare the EMG activity in maximal voluntary clench of the masseter and anterior temporalis muscles of patients with advanced tooth wear to the same activity of healthy volunteers. DESIGN 50 (16F, 34M) patients and 30 (12F, 18M) age matched controls were clinically examined to assess the degree of wear (TWI). Each subject underwent electromyographic analysis (bilateral anterior temporalis, superficial masseter, anterior digastric and sternocleidomastoid muscles) and digital occlusal analysis. RESULTS Mean values of the electrical potentials of the mandible elevating muscles during clench were higher in the study group compared to the controls. A negative correlation was found between the temporalis and masseter muscle activities during clench and the mean value of TWI (r=-0.383, p=0.009; r=-0.447, p=0.002). Occlusion time was longer in the study group compared to controls (p<0.05). CONCLUSIONS Mandibular adductors demonstrated lower muscular activities during clenching in the tooth wear patients; however, the cause of this finding is not certain. Prolongation of occlusion time may exacerbate occlusal surfaces wear or excessive wear may prolong occlusion time.

Evaluation of estrogen receptor-β expression in the epithelium of the oral mucosa in menopausal women under hormone replacement therapy

PURPOSE We aimed to evaluate the ERβ expression in the epithelium of the oral mucosa in menopausal women treated with oral, transdermal or local (vaginal) menopausal hormone therapy. MATERIAL/METHODS In this study, we included 60 women treated with oral, transdermal or vaginal menopausal hormone therapy. The study material was obtained from swabs taken from the buccal mucosa before administering HRT, and after 6 weeks, 3 months, 6 months and 12 months of therapy. We assessed estrogen receptor-β (ERβ) expression levels in subsequent swabs by immunohistochemical analysis. RESULTS The highest increase in the ERβ expression was observed after 3 months of oral and transdermal hormone therapy. CONCLUSIONS Oral and transdermal HRT may be an effective method of treatment of oral discomfort in menopausal women.

Salivary protective factors in patients suffering from decompensated type 2 diabetes

PURPOSE Defining the level of protective factors in saliva of patients suffering from decompensated type 2 diabetes. MATERIAL AND METHODS 50 Patients with diagnosis of decompensated type 2 diabetes, including 32 women and 18 men at the age of 57.9±9.2 years. The control group consisted of 50 people among whom there were 38 women and 12 men whose average age was estimated at 51.2±9.9 years. RESULTS It was stated the increased concentration of total protein by 60% and decreased concentration of IgA by 70%, of lysozyme by 27% and of lactoferrin by 40% in resting saliva of patients with type 2 diabetes if compared to the control group. These outcomes were really statistically meaningful. The evaluation of dependences between the analyzed protective factors and the indicator of oral cavity condition proved the positive correlation between the concentration of total protein and the number of DMFT (i.e. the rate of caries intensity). The remaining coefficients of correlation being evaluated proved to be negative and statistically meaningless. CONCLUSION The obtained outcomes prove a high influence of proteins included in saliva on the prevalence and development of caries at patients with decompensated type 2 diabetes.

The evaluation of zinc and copper content in tooth enamel without any pathological changes – an in vitro study

Objectives The objectives of the study were to evaluate the content of copper and zinc in individual layers of tooth enamel and to analyze the relationships between the study minerals in individual layers of tooth enamel. Patients and methods Fifteen human permanent teeth were cut off every 150 μm alongside the labial surface. Acid biopsy of each layer was performed. The zinc content was determined using the air–acetylene flame method. The copper content was determined using the electrothermal technique with argon. Results The mean zinc concentrations increased significantly starting from the outer enamel surface, with the maximum concentration in the 150–300 μm layer. The mean copper concentrations increased substantially from the outer enamel surface to a depth of 150 μm, and then a slight downward trend of this mineral levels was seen, down to a depth of 450 μm. Strong positive correlation was found between the zinc and copper concentrations at depths of 150–300, 450–600 and 600–750 μm. Conclusion The levels of zinc and copper in the outer enamel layers may have an effect on the increased content of unipolar minerals at deeper enamel layers. The content of the study elements determined may reflect the process of mineralization and maturation of enamel in the pre-eruption period.

Immunohistochemical evaluation of oestrogen receptors α and β in epithelium of the vaginal mucous membrane in women after oestrogen therapy

Oestrogens act on target cells through α and β receptors (ERα and ERβ). Expression of oestrogen receptors is associated with the age and menopausal condition of women. The aim of the study was an immunohistochemical evaluation of ERα and ERβ receptors in epithelium of the vaginal mucous membrane of women subjected to different forms of hormonal therapy (HTM). Oestrogen receptors ERα and ERβ were identified using immunohistochemical methods and evaluated in smears of vaginal mucous membranes collected from 60 patients subjected to HTM (including 20 patients after oral therapy, 20 patients after transdermal therapy, and 20 patients after vaginal therapy). The results showed a significant change in immunoreactivity of both studied receptors after three months of hormone therapy. The biggest differences in the changes of intensity of ERα and ERβ reactions were observed in patients subjected to vaginal therapy. Immunostaining for α receptor showed differences between three types of hormone therapy. The highest increase in the overall intensity occurred after three months of topical therapy. Immunostaining for Erβ also varied for different types of hormone therapy. The results indicate that hormone therapy administered vaginally is the most effective in the treatment of urogenital ailments during menopause. In addition, topical therapy eliminates adverse effects of systemic oestrogen.

The influence of occlusal morphology on occlusion time

Objectives: The aim of the study was to assess how the morphology of the occlusal surfaces of premolars and molars influenced the occlusion time in a mixed gender group of young adults with full natural dentition. Methods: Fifty healthy volunteers with Angle’s Class I occlusion were included in the study. After clinical examination, the alginate impressions of both arches were taken, and plaster casts were prepared. To assess the morphology of lateral teeth, the digital models were measured. Occlusal analysis was performed with the T-Scan® III to assess occlusion time. Results: A direct correlation was found between the cusp distance for the first upper premolar and occlusion time (r = −0.29, p<0.05) and the distance between distal buccal and distal lingual cusps of the first lower premolar and occlusion time (r = 0.33, p<0.05). The parameters that had their impact on occlusion time were the opening angle of lingual cusps for the lower molars and the furrow angle of aperture between cusps for first upper premolar. Discussion: Occlusal surface morphologies of premolars may have direct impact on occlusion time. However, anterior guidance parameters and morphologies of molars could also influence the time teeth are in contact coming to maximal intercuspation.

Relationship between depression and masticatory muscles function in a group of adolescents

Abstract Objective: The aim of the study is to determine association between depressive symptoms and the electrical activity of muscles in maximum voluntary clench in a group of young adults. Methods: A total of 186 volunteers (Females = 98, Males = 88), with a mean age of 19 years, were recruited to the study. All participants took a questionnaire survey stating the level of depression (Beck’s scale), clinical examination, and instrumental diagnostics (EMG). Results: Symptoms of mild or medium depression were found in 35 of the subjects (18.82%). Average electric potentials of the masticatory muscles in maximal voluntary clench were significantly higher among the subjects with depression symptoms in comparison with subjects without those symptoms (85.96 ± 10.25 vs 78.97 ± 15.32, p < . 0.05). Discussion: An increase in the electrical potentials of masseter muscles in maximal voluntary clench was found in the group with depression symptoms. The study should be continued to confirm this finding.