Three-Dimensional Assessment of Upper Airway Volume and Morphology in Patients with Different Sagittal Skeletal Patterns.

BACKGROUND: The relationship between respiratory function and craniofacial morphology has garnered significant attention due to its implications for upper airway and stomatognathic development. Nasal breathing plays a key role in craniofacial growth and dental positioning. This study investigated upper airway morphology and volume differences among individuals with class I, II, and III skeletal anomalies. METHODS: Ninety orthodontic patients' CBCT scans were analyzed to assess the oropharynx and hypopharynx volumes. Skeletal diagnosis was established based on the cephalometric analysis. RESULTS: A significant volume change in the oropharynx and pharynx was demonstrated when comparing class II with class III anomalies (p = 0.0414, p = 0.0313). The total volume of the pharynx was increased in class III anomalies. The area of the narrowest part of the pharynx (MIN-CSA) significantly decreased in classes I and II compared to class III (p = 0.0289, p = 0.0003). Patients with Angle class III anomalies exhibited higher values in the narrowest pharyngeal segment. Gender differences were significant in pharyngeal volumes and morphologies across malocclusion classes. CONCLUSIONS: The narrowest segment of the pharynx had the highest values in patients with Angle class III. The volume of the oropharynx was found to be greater in patients with Angle class III versus patients with Angle class II.

Bruxism in Children and Adolescents and its Association with Some Possible Aetiological Factors.

Bruxism is a nocturnal parafunctional activity represented by grinding and clenching of the teeth. Bruxism is considered to be the most harmful of the parafunctional activities of the stomatognathic system, being responsible for tooth wear, periodontal lesions and joint and/or muscle lesions. This study consists of a group of 189 children (111 male and 78 female) that responded correctly and completely to a questionnaire that contained nine items assessing sleep bruxism. According to our research, there was a statistically significant association between bruxism and headache (p<0.0001), tooth/gingival sensitivity (p<0.0001), muscle stiffness, presence of stress (p<0.0001), and vicious habits. Within the limits of this study, parafunctional phenomena such as nocturnal bruxism interest an important percentage, over 60%, involving children of both genders in relatively equal proportions.

Study Regarding the Monitoring of Nocturnal Bruxism in Children and Adolescents Using Bruxoff Device.

Bruxism is a parafunctional activity represented by the gnashing and clenching of one's teeth. The aim of this study was to determine the utility of screening and monitoring with a Bruxoff device during nocturnal bruxism in 51 children and adolescents (36 with bruxism and 15 without bruxism) by assessing the variations in the intensity and duration of parafunctional activity in each patient. Bruxoff measurements were recorded for at least 60 min for three consecutive nights for each subject. All the parameters recorded using Bruxoff in the control and the study groups showed a statistically significant difference (p < 0.05). The differences found by comparing the values recorded in the male and female study groups are significant for heart rate, the number of masseter muscle contractions during one night, and mixed contractions. The Bruxoff device proved to be important in diagnosing patients with bruxism in our practice.

Evaluation of Intraoral Full-Arch Scan versus Conventional Preliminary Impression.

An accurate impression is vital during prosthodontic rehabilitation. Digital scanning has become an alternative to conventional impressions. This study compares conventional preliminary impression techniques with digital scanning, evaluating the efficiency, treatment comfort, and trueness. Impressions of 28 patients were taken using conventional and digital techniques. The efficiency of both impression techniques was evaluated by measuring the mean working time. A visual analog scale questionnaire (1-10) was used to appreciate the participants' perceptions of discomfort. Morphometric measurements, which were carried out to determine the differences between the casts, were made on the buccolingual cross sections of teeth 11 and 31 and the distolingual and mesiobuccal cusp tips of each first molar. The total treatment time was 75.5 min for conventional and 12 min for digital impressions. The patients scored a mean discomfort assessment of 6.66 for conventional and 9.03 for digital scanning. No significant differences existed between the examined areas (p < 0.05, Wilcoxon and Mann-Whitney tests) of the digital casts obtained by both techniques. The intraoral scan can be considered as an alternative to conventional preliminary impressions for performing study model analysis during orthodontic treatment planning. The digital impression is more comfortable and accepted by the patients than the conventional impression and has a shorter working time.

Full-Mouth Rehabilitation of a Patient with Gummy Smile-Multidisciplinary Approach: Case Report.

The impairment of aesthetic function leads to a decreased quality of life. An unaesthetic smile due to excessive gingival exposure demands, most of the time, a complex treatment in which the objective is the vertical reduction of the amount of exposed fixed gingiva by obtaining a complete exposure of the anatomical crown of the teeth and restoring the ideal dimensions of the biological width. This paper presents a case of a 48-year-old female patient who was unsatisfied with her aesthetics and had disturbed masticatory function due to the absence of some posterior teeth. The cone beam computed tomography was performed to evaluate the facial and dental morphology. The treatment plan included diode laser and piezo-surgery utilization for the frontal area of the upper arch and implants to restore the distal area of the lower and upper arch. Zirconia ceramic was used for the final restorations. This complex and multidisciplinary full-mouth rehabilitation lasted for two years, and the patient was pleased with the result. This case showed that a well-established treatment plan is necessary to obtain long-lasting results. The use of adequate procedures and equipment ensures a predictable result.

Influence of the Operator`s Experience, Working Time, and Working Position on the Quality of the Margin Width: In Vitro Study.

Background and Objectives: Appropriate tooth preparation is mandatory to obtain a perfect marginal fit of fixed restorations. The heavy chamfer is the most commonly used finish line, especially for minimally invasive tooth preparation. The aim of the study was to compare the width of the finish line obtained during tooth preparation performed by experienced (university lecturers) and inexperienced persons (dental students) in different working times and positions. Materials and Methods: Forty left upper-second molars were prepared on the simulator by each participant, totalizing 160 prepared teeth. A new round-end tapered diamond was used to obtain the 0.5 mm width of the heavy chamfer. The prepared teeth were photographed using a Canon D5300 camera with a macro lens attached to a tripod. The measurements were made with the Image-Pro Insight software selecting the same eight reference points. From these points, perpendicular lines were drawn above the finish line to the axial walls and the distance between the chamfer's outer edge and the axial wall's inner edge was measured. GraphPad Instat and NCSS Dowson Edition software were used. The statistical significance was set at p < 0.05. The mean (M) and standard deviation (SD) were calculated. The used tests: one sample t-test, ANOVA test, and Tukey-Kramer Multiple Comparisons Test. Results: Statistically significant differences were obtained according to the experience of the participant, preparation time, patient's position, and the chamfer width on the prepared tooth different surfaces. Conclusions: Daytime or weeklong tiredness and patient position do not affect the width of the heavy chamfer prepared by experienced and inexperienced persons. The experience and the operator's working position influence the width of the prepared finish line.

Cyclooxygenase-2 and matrix metalloproteinase-9 expressions correlate with tissue inflammation degree in periodontal disease.

INTRODUCTION: Cyclooxygenase-2 (Cox-2) and matrix metalloproteinase-9 (MMP-9) have synergistic effects in the degradation of the extra-cellular matrix. OBJECTIVE: The aim of our study was to correlate the intensity of inflammation with MMP-9 and Cox-2 expression in the periodontal tissue of patients with chronic inflammatory disease (gingivitis and chronic periodontitis) in order to determine the role of these two biomarkers in the progression of periodontal disease. MATERIALS AND METHODS: To conduct this study we analyzed the gingival biopsies taken from patients clinically divided into three study groups: Group I (control): Patients free of periodontal disease (seven biopsies); Group II: Patients with gingivitis (10 biopsies); Group III: Patients with chronic periodontitis (10 biopsies). In these three groups, we graded the intensity of inflammation in the lamina propria and the immunohistochemical expression of MMP-9 and Cox-2. RESULTS: The presence of a large number of inflammatory cells in the lamina propria in patients with gingivitis or chronic periodontitis (Groups II and III) correlated with the clinically diagnosed inflammation of the gingival tissue. The expression of MMP-9 was higher in patients with chronic periodontitis than in those with gingivitis, showing a trend towards statistical significance (p=0.07, Mann-Whitney U-test). The expression of Cox-2 in periodontitis was also higher compared to gingivitis (p=0.05, Mann-Whitney U-test) and to controls (p=0.001, Mann-Whitney U-test).The inflammation score could be positively correlated to the MMP-9 and Cox-2 expression scores at the overall study group, but not separately on gingivitis and periodontitis patients. CONCLUSIONS: The presence of an intensive inflammatory infiltrate is characteristic both for periodontitis and gingivitis. MMP-9 and Cox-2 show higher expression in periodontitis, than in gingivitis and healthy controls, but MMP-9 and Cox-2 expression scores cannot be directly correlated to the grade of inflammatory infiltrate in the two different disease entities. As biomarkers of chronic inflammation activity, angiogenesis, and degradation of the extracellular matrix, MMP-9 and Cox-2 can be used in clinical practice for the detection of patients with chronic periodontitis risk, at whom treatment with Cox-2 and MMP-9 inhibitors may be considered.