16 research outputs found
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Chronic periodontitis and its possible association with oral squamous cell carcinoma â a retrospective case control study
Introduction: Different inflammatory processes may trigger the development of malignancies. Therefore, the aim of the present study was to evaluate a potential association between radiological determined chronic periodontitis (CPA) and oral squamous cell carcinoma (OSCC). Methods: In a retrospective study, OSCC-patients and a control group without malignant tumors were radiographically examined for bone loss. Via telephone survey and questionnaire, general clinical data on the individual oral hygiene and concomitant diseases together with tobacco and alcohol use were assessed and data were compared between the groups. Results: 178 OSCC-patients and 123 controls were included. In univariate analysis, a statistically relevant higher mean bone loss was seen in the OSCC group (4.3 mm (SD: 1.8; 95% confidence interval (CI): 4-4.6) vs. 2.9 mm (SD: 0.7; 95% CI: 2.8-3); p < 0.001)). This was confirmed in a multivariate regression model (OR: 2.4, 95% CI: 1.5-3.8; p < 0.001). A history of periodontal treatment was associated with significantly reduced OSCC risk (p < 0.001; OR: 0.2, CI: 0.1-0.5). Conclusions: CPA is a common disease and the monitoring as well as the treatment of such a chronic oral inflammation may be beneficial in reducing one potential cause of OSCC. Therefore, further clinical studies on oral neoplasms should consider clinical periodontal parameters as well
An Assessment of the Influence of Dental Porcelain Slurry Preparation on Flexural Strength of Different Feldspathic Porcelains
Chipping remains a big challenge during the clinical application of glass ceramics in dentistry. The fabrication procedure used affects the mechanical properties of dental feldspathic porcelain and is associated with technical failures. This study aimed to compare the effect of the use of manufacturersâ liquids versus H2O on the flexural strength of glass ceramics. Specimens (n = 120, n = 15 per group) (25 Ă 4 Ă 1.2 mm) were obtained using four porcelain powders (Creation CC, IPS InLine, Noritake EX-3, and Vita VM 13). Four groups were produced using porcelain powder and modeling liquid, and four groups using distilled water. The specimens were fired, sintered, and polished. Flexural strength was measured using a universal testing machine. Statistical analyses were conducted using post hoc Tukeyâs, two-way ANOVA, and Weibull analysis. Flexural strength values (mean ± SD) of the ceramic-manufacturerâs liquid mixture ranged between 67.2 ± 10.2 and 85.8 ± 12.8 MPA (NR < VT < IV < CR), while flexural strength values of the ceramicâwater mixture were between 72.2 ± 6.9 and 95.2 ± 12 MPA (CR < NR < VT < IV). While the choice of the ceramic type significantly affected flexural strength, the use of water vs. manufacturersâ liquid showed in almost all cases no significance. To achieve better flexural strength results, InLine should be used with distilled water mixtures, while all ceramic powders except for Noritake can be used with the manufacturerâs liquid mixtures
Volumetric Analysis of Allogenic and Xenogenic Bone Substitutes Used in Maxillary Sinus Augmentations Utilizing Cone Beam CT: A Prospective Randomized Pilot Study
PURPOSE The purpose of this prospective randomized clinical pilot study was to compare the three-dimensional changes of grafted maxillary sinuses when deproteinized bovine bone (DBB) or cortical mineralized allogeneic bone (MAB) was used.
MATERIALS AND METHODS Seventeen patients were randomly assigned to receive either DBB or MAB for lateral-approach maxillary sinus augmentation. Cone beam computed tomography (CBCT) scans were performed preoperatively (T0), immediately after (T1), and at approximately 6 months posthoperatively (T2). Three-dimensional analysis of the radiographic volumetric changes was performed for DBB and MAB by measuring the difference in unoccupied sinus volumes at T1 and T2.
RESULTS In the DBB group, a statistically significant increase in unoccupied sinus volume was found at T2 when compared to T1 (P = .001). It represents a mean resorption rate of 23.8% ± 15.9%. Similarly in the MAB group, a statistically significant increase in unoccupied sinus volume was found at T2 when compared to T1 (P = .007). The mean resorption rate in the MAB group was 19.5% ± 10.1%. There was no statistically significant difference between the contraction of DBB (23.8%) and MAB (19.5%) (P = .52).
CONCLUSION Both DBB and MAB showed sufficient volume stability at T2 (mean 6.3 ± 1.6 months) postoperatively for 10- to 13-mm-implant placement without the need for additional grafting
Tooth Shade Relationship with Age, Gender, and Skin Color in a Saudi Population: A Cross-Sectional Study
Objectives: The aim of this study was to assess the relationship between tooth shade among different groups of patients according to their age, gender, and skin color in a Saudi population. Materials and methods: Participants were divided based on age into Group 1 (10â20 years), Group 2 (21â30 years), Group 3 (31â40 years), and Group 4 (41+ years), and according to gender. Tooth shade was measured by Vita easyshade, Shade scanner, 3D Master shade system. The skin color was determined according to the Firzpatrick Scale. It consists of six shades, namely: I, II, III, IV, V, and VI. The skin complexion of the participants was divided into six categories: white/very fair, fair, light brown, moderate brown, dark brown, and black. Results: One hundred and ninety-eight individuals were recruited. Around 70% were males. Females had 25.4% A2 followed by 22% A1, and 22% A3 shade types, while males had B3 shade (18%) followed by A2 and A3 (15.8%). A statistically significant difference was observed between shade and gender (p p p Conclusions: In conclusion, the most frequent classical shade noted among male and female participants was shade type A, which represents reddish brownish. Group 2 (21â30 years) had the B3 shade as the most prominent shade type among age groups. Gender, age, and skin types all showed a significant relation with the tooth shade
Platelet-Derived Growth Factor Stimulated Migration of Bone Marrow Mesenchymal Stem Cells into an Injectable Gelatin-Hydroxyphenyl Propionic Acid Matrix
Bone marrow mesenchymal stem cells (bMSCs) are responsible in the repair of injured tissue through differentiation into multiple cell types and secretion of paracrine factors, and thus have a broad application profile in tissue engineering/regenerative medicine, especially for the musculoskeletal system. The lesion due to injury or disease may be a closed irregular-shaped cavity deep within tissue necessitating an injectable biomaterial permissive of host (endogenous) cell migration, proliferation and differentiation. Gelatin-hydroxyphenyl propionic acid (Gtn-HPA) is a natural biopolymer hydrogel which is covalently cross-linked by horseradish peroxidase (HRP) and hydrogen peroxide (H2O2) in situ and can be delivered to the lesion by needle injection. Growth factors and cytokines can be directly incorporated into the gel or into nano- and micro-particles, which can be employed for sustained release of biomolecules while maintaining their bioactivity. In this study, we selected polyelectrolyte complex nanoparticles (PCNs) prepared with dextran sulfate and chitosan as the carrier for platelet-derived growth factor (PDGF)-BB and stromal cell-derived factor (SDF)-1α, which have been tested effectively in recruiting stem cells. Our in vitro results showed a high degree of viability of bMSCs through the process of Gtn-HPA covalent cross-linking gelation. The Gtn-HPA matrix was highly permissive of bMSC migration, proliferation, and differentiation. PDGF-BB (20 ng/mL) directly incorporated into the gel and, alternatively, released from PCNs stimulated bMSC migration and proliferation. There were only small differences in the results for the direct incorporation of PDGF into the gel compared with its release from PCNs, and for increased doses of the growth factor (200 ng/mL and 2 ”g/mL). In contrast, SDF-1α elicited an increase in migration and proliferation only when released from PCNs; its effect on migration was notably less than PDGF-BB. The in vitro results demonstrate that PDGF-BB substantially increases migration of bMSCs into Gtn-HPA and their proliferation in the gel, and that these benefits can be derived from incorporation of a relatively low dose of the growth factor directly into the gel. These findings commend the use of Gtn-HPA/PDGF-BB as an injectable therapeutic agent to treat defects in musculoskeletal tissues
Tooth Shade Relationship with Age, Gender, and Skin Color in a Saudi Population: A Cross-Sectional Study
Objectives: The aim of this study was to assess the relationship between tooth shade among different groups of patients according to their age, gender, and skin color in a Saudi population. Materials and methods: Participants were divided based on age into Group 1 (10–20 years), Group 2 (21–30 years), Group 3 (31–40 years), and Group 4 (41+ years), and according to gender. Tooth shade was measured by Vita easyshade, Shade scanner, 3D Master shade system. The skin color was determined according to the Firzpatrick Scale. It consists of six shades, namely: I, II, III, IV, V, and VI. The skin complexion of the participants was divided into six categories: white/very fair, fair, light brown, moderate brown, dark brown, and black. Results: One hundred and ninety-eight individuals were recruited. Around 70% were males. Females had 25.4% A2 followed by 22% A1, and 22% A3 shade types, while males had B3 shade (18%) followed by A2 and A3 (15.8%). A statistically significant difference was observed between shade and gender (p < 0.05). A statistically significant difference was observed between shade and age group (p < 0.05), where increased age was correlated with darker teeth shades. Shade A1 was correlated with type I skin color in 57.1% of individuals. Skin color type II had A2 as a dominant shade by 34.1%. A2 and A3 shades were equally observed in skin color III by 20.3%. Overall, statistically significant differences were observed between shade and skin color groups (p < 0.05). Conclusions: In conclusion, the most frequent classical shade noted among male and female participants was shade type A, which represents reddish brownish. Group 2 (21–30 years) had the B3 shade as the most prominent shade type among age groups. Gender, age, and skin types all showed a significant relation with the tooth shade
Clinical and histologic evaluation of different approaches to gain keratinized tissue prior to implant placement in fully edentulous patients
OBJECTIVES: This work aimed to investigate the effectiveness and predictability of different treatment modalities for gain of keratinized tissue (KT) in fully edentulous jaws prior to dental implant placement: apically positioned flap (APF), APF plus xenogeneic collagen matrix (XCM), and APF plus free gingival graft (FGG).
MATERIALS AND METHODS: In fully edentulous patients with insufficient zones of KT at the prospective implant positions, four treatment modalities were performed in the lower jaw: APF, XCM, FGG, and an untreated control group (control). APF and XCM were applied in the first molar positions, FGG and control in the canine positions. Assessed outcomes up to 3Â months post-surgery included changes in width of KT (over a 3-month period), histomorphometric analysis of harvested soft-tissue biopsies (at 3Â months postoperatively), and patient-reported outcomes measures (PROMs).
RESULTS: For the primary outcome, changes in KT width demonstrated an increase of 1.93 ± 1.6 mm (APF), whereas XCM and FGG showed an increase of 4.63 ± 1.25 mm and 3.64 ± 2.01, respectively. Histomorphometric analyses revealed a thickness of the epithelium ranging between 375â±â122 Όm (APF), 410â±â116 Όm (XCM), 336â±â122 Όm (FGG), and 413â±â109 Όm (control). All biopsies showed a regular muco-periosteal structure with a keratinized epithelium of comparable thickness in all groups.
CONCLUSION: All three methods were suitable to increase the width of KT, although APF alone rendered roughly 50% less gain compared to XCM and FGG.
CLINICAL RELEVANCE: The use of XCM in conjunction with an APF represents a valuable treatment option for the gain of keratinized tissue in edentulous sites