Effect of preparation design and endodontic access on fracture resistance of zirconia overlays in mandibular molars: An in vitro study.

PURPOSE: To evaluate the fracture resistance of zirconia overlays, considering various preparation designs and the presence of endodontic access. MATERIALS AND METHODS: Ninety translucent zirconia (5Y-PSZ) overlay restorations were divided into six groups (n = 15/group) based on different preparation designs, with and without endodontic access: chamfer margin 4 mm above the gingival level without (group 1) and with endodontic access (group 2); margin 2 mm above the gingival level without (group 3) and with endodontic access (group 4); overlay with no chamfer margin without (group 5) and with endodontic access (group 6). Restorations were bonded to mandibular first molar resin dies, and the groups with endodontic access were sealed with flowable resin composite. All restorations underwent 100,000 cycles of thermal cycling between 5°C and 55°C, followed by loading until fracture. Maximum load and fracture resistance were recorded. ANOVA with Tukey post-hoc tests were used for statistical comparison (α < 0.05). RESULTS: Fracture resistance significantly varied among overlay designs with and without endodontic access (p < 0.001), except for the no-margin overlays (groups 5 and 6). Overlays with a 2 mm margin above the gingival margin with endodontic access (group 4) exhibited significantly higher fracture resistance compared to both the 4-mm supragingival (group 2) and no-margin (group 6) designs, even when compared to their respective intact groups (groups 1 and 5). There were no significant differences between the no-margin and 4-mm supragingival overlays. CONCLUSION: The more extensive zirconia overlay for mandibular molars is the first choice since the 2 mm margin above the gingival level design withstood considerable loads even after undergoing endodontic access. A no-margin overlay is preferred over the 4-mm supragingival design as it preserves more tooth structure and there was no outcome difference, irrespective of endodontic access. Caution is warranted in interpreting these findings due to the in vitro nature of the study.

Influence of gingival display on smile attractiveness assessed by Saudi Arabian laypersons and dental professionals.

This study was undertaken to evaluate the influence of changes in the gingival display of the maxillary teeth on smile attractiveness assessed by Saudi Arabian dental professionals and laypeople. A total of 138 dental professional and 182 laypeople rated the attractiveness of male and female smiles in a computerized survey. A smiling photograph of a male and a female dental students were selected and digitally manipulated to create changes the amount of gingival display from 4 mm of gingival display to 4mm of gingival covered by the upper lip in 1 mm increments. Each photo was accompanied by a visual analog scale (VAS) for rating. Among dental professionals, 61% rated the female photo with a 1-mm low lip line as the most attractive smile (VAS score ± SE, 7.3 ± 3.18), while 52.7% of laypeople considered the smile with a 2-mm low lip line as the most attractive (6.7 ± 3.4). Regarding male smile photos, 61.6% of dental professionals found the 1-mm low lip line the most attractive (7.3 ± 3.18). The same rating was given by 48.3% of laypeople (6.1 ± 3.6) (p ≤ 0.009). The least attractive smile photo was the smile showing 4 mm of gingiva for male and female smiles. More than half of the laypeople believed that an attractive smile highly affects social life and communication. The Saudi Arabian population appears to be sensitive to the amount of gingival display. The difference in female smile assessment between dental professionals and laypeople highlights the importance of dentist-patient consensus regarding decisions for esthetic treatments. Esthetic treatment is of a major concern for both dentist and patient. The careful assessment of smile pillars including gingival display must be tailored to each patient.

Gingival Pigmentation Features in Correlation with Tooth and Skin Shades: A Cross-Sectional Study in a Saudi Population.

PURPOSE: The present study aimed to observe the anatomical distribution of gingival melanin pigmentation and evaluate its intensity and extent in different age groups and in correlation with skin and tooth shades. MATERIALS AND METHODS: The participants of this study were 391 patients attending the Dental University Hospital. The presence of gingival pigmentation was assessed using De Krom's Oral Pigmentation Chart and its intensity was assessed using the Dummett-Gupta Oral Pigmentation Index. Skin colour and tooth shade were measured using the Fitzpatrick scale and the VITA classical shade guide, respectively. Statistical analyses included descriptive statistics and Pearson's Χ2 test for the association between the study variables. RESULTS: The prevalence of gingival pigmentation among the sample size was 74.4%, and pigmentations were present on both arches in 57.6% (n = 224) of the participants. The extent (category 1) was highest when pigmentation was evident in both arches, with category 4 being the least extent. Age and sex did not show a correlation with gingival pigmentation. Gingival pigmentation intensity was mild when pigments were present in one arch (p < 0.00), whereas it was heavy when both arches presented with gingival pigmentation. Medium brown colour and tooth shade A1 were the most common among participants with gingival pigmentation (p < 0.00). The association between gingival pigmentation intensity and extent in relation to skin colour was statistically significant (p < 0.00), as was tooth shade (p < 0.05). CONCLUSIONS: Gingival pigmentation is highly prevalent in the Saudi population, with different severity and extent levels. The effect of gingival pigmentation on smile and overall facial aesthetics should be considered when providing dental and cosmetic treatments.

Dental students' attitudes and perceptions about intraprofessional collaboration/education.

Objectives: To investigate dental students' attitudes and perceptions about intraprofessional collaboration/education (IPC/IPE) and shared learning, and to explore the impact of IPC/IPE on the personal and professional development of participating students. Methods: A custom-designed questionnaire was used in this cross-sectional study. The questionnaire comprised 17 questions targeting to capture the student's perceptions about IPC/IPE using three factors: (1) dental students' preference/opinion about the IPC/IPE; (2) dental students' experience about the impact of IPC/IPE on learning outcomes and professional development; and (3) students' feedback about the significance of IPC/IPE in clinical/clinical simulation labs and workplace setting. The students rated each of the 17 statements on the 5-point Likert scale (range: 1 = strongly disagree to 5 = strongly agree). Results: A total of 259 responses were analysed (response rate = 65%). All students were aware of IPC/IPE in the field of dentistry (mean score = 4.22). The students preferred collaborative/shared learning with their own classmates. There was a consensus among students about the positive impact of IPC/IPE on enhanced learning, enhancement of communication skills, and enrichment of professional relationships with supporting staff as well as with the patients. There was also improved analytical and psychomotor skills, understanding of complex problems in the clinic, and understanding of strengths and limitations leading to self-improvement and increased efficiency and productivity. Conclusion: IPC/IPE had a compelling, powerful, and positive impact according to the experience of the participating dental students. It is recommended that a standardized curriculum be designed and guidelines set for IPC/IPE at dental institutions for effective interactions among students of all stages.

Incidence of maxillary sinus septa in the saudi population.

BACKGROUND: The variability in the maxillary sinus anatomy makes dental implant planning challenging. One of the anatomical landmarks that could affect the decision for implant placement around the maxillary sinus is the sinus septa. This study aimed to retrospectively determine the prevalence, anatomical distribution, and morphology of the maxillary sinus septa. MATERIALS AND METHODS: This study included 309 CBCT images that were analyzed to determine the prevalence, height, location, and orientation of the maxillary sinus septa. Descriptive statistics, Mann‒Whitney U tests, and Kruskal‒Wallis tests were used for data analysis. RESULTS: A total of 618 maxillary sinuses were analyzed. Maxillary septa were present in 30% (n = 188) of the sinuses and in approximately 45% of the analyzed images. The mean height of the septa was 5.09 mm. The presence of bilateral septa was evident in 49 subjects (35.25%). Female subjects were significantly more likely to have only one septum (n = 67, 53.6%, p < 0.05). CONCLUSION: The presence of septa is very common, found in one-third to approximately half of the evaluated cases, which warrants careful examination before any surgical interventions to avoid possible complications.

Evaluating the Translucency, Surface Roughness, and Cytotoxicity of a PMMA Acrylic Denture Base Reinforced with Bioactive Glasses.

The colonisation of the surface of removable acrylic dentures by various types of microorganisms can lead to the development of various diseases. Therefore, the creation of a bioactive material is highly desirable. This study aimed to develop a denture base material designed to release bioactive ions into the oral environment during use. Four types of bioactive glasses (BAG)-S53P4, Biomin F, 45S5, and Biomin C-were incorporated into the PMMA acrylic resin, with each type constituting 20 wt.% (10 wt.% non-silanised and 10% silanised) of the mixture, while PMMA acrylic resin served as the control group. The specimens were subsequently immersed in distilled water, and pH measurements of the aqueous solutions were taken every seven days for a total of 38 days. Additionally, surface roughness and translucency measurements were recorded both after preparation and following seven days of immersion in distilled water. The cytotoxicity of these materials on human fibroblast cells was evaluated after 24 and 48 h using Direct Contact and MTT assays. Ultimately, the elemental composition of the specimens was determined through energy-dispersive X-ray (EDX) spectroscopy. In general, the pH levels of water solutions containing BAG-containing acrylics gradually increased over the storage period, reaching peak values after 10 days. Notably, S53P4 glass exhibited the most significant increase, with pH levels rising from 5.5 to 7.54. Surface roughness exhibited minimal changes upon immersion in distilled water, while a slight decrease in material translucency was observed, except for Biomin C. However, significant differences in surface roughness and translucency were observed among some of the BAG-embedded specimens under both dry and wet conditions. The composition of elements declared by the glass manufacturer was confirmed by EDX analysis. Importantly, cytotoxicity analysis revealed that specimens containing BAGs, when released into the environment, did not adversely affect the growth of human gingival fibroblast cells after 48 h of exposure. This suggests that PMMA acrylics fabricated with BAGs have the potential to release ions into the environment and can be considered biocompatible materials. Further clinical trials are warranted to explore the practical applications of these materials as denture base materials.

The effect of systemic Isotretinoin on salivary tissue inhibitors of metalloproteinases 1 and 2 and salivary flow rate in periodontal disease.

AIMS: To evaluate and compare changes in salivary flow rate and salivary levels of TIMP-1 and TIMP-2 in individuals taking oral Isotretinoin (INN) with those who do not take INN. To assess the variation in TIMP-1 and TIMP-2 as well as salivary flow rate observed at different stages of periodontal disease in comparison to those observed in the case of healthy periodontium. MATERIALS AND METHODS: An examiner-blind case-control study involving 180 human adults divided into six groups based on their periodontal status. Clinical parameters, including pocket depth, clinical attachment level, and bleeding on probing were measured at six sites per tooth. Whole unstimulated saliva samples were collected from all subjects to evaluate salivary flow rate (SFR). Salivary TIMP-1 and TIMP-2 levels were detected using enzyme-linked immunosorbent assay (ELISA). Data were analyzed using IBM SPSS Software. The Kruskal Wallis test and Mann-Whitney U-tests were employed to verify any significant differences between the groups for all parameters. Multi-regression analysis was performed for each parameter tested in each group. All tests were compared at a significance level of 0.05. RESULTS: SFR was statistically significantly lower among all INN groups in comparison to the control groups (P < 0.001). TIMP-1 and TIMP-2 were significantly higher in all INN groups in comparison to the control groups, in both gingivitis cases (P = 0.004, P < 0.0001 respectively) and periodontitis cases (P < 0.0001). CONCLUSION: Although INN reduces salivary flow rate, the findings of the present study revealed that it had an anti-inflammatory effect in periodontal biomarkers. Specifically, it was positively correlated with an elevation of salivary TIMP-1 and TIMP-2. Hence, INN might be a future additive medication to be further evaluated for the treatment of periodontal diseases.

Evaluation of complacency about dental implants with shared decision making and satisfaction scores: A cross-sectional study.

BACKGROUND: The dentist-patient relationship is delicate. Engaging the patient in the dental treatment planning especially for lengthy procedures as dental implants improves the relation as well as treatment outcomes including patient satisfaction. We aimed at evaluating the importance of Shared Decision making (SDM) and level of satisfaction among dental implant patients by employing SDM and satisfaction scores. MATERIALS & METHODS: The present cross-sectional study was pursued between April 2019 to September 2019, among dental implant patients (n = 144) who have completed their prosthetic part of implant treatment with at least 3 months of post-restoration evaluation. Demographic and implant data were collected from electronic filing system (Salud) as well as measurement of SDM score. Data were analyzed using SPSS 24.0 version statistical software. RESULTS: The mean satisfaction score was higher for implant placement with Periodontists (31.9%). However, among surgical specialist the mean satisfaction score was found to be higher for oral surgeons who had 1-5 years of experience (46.5%). Patients reported that their decision making was greatly influenced by the treating dentist. A statistical significance was found where (64.6%) of Implant patients would like to undergo the procedure again (p < 0.0001). CONCLUSION: Shared decision-making and patient satisfaction enables the treatment delivery to be more effective and ethical, in addition to being patient-centered care.

Antimicrobial Effect of Isotretinoin Therapy on Periodontal Pathogens: A Case-Control Study.

Isotretinoin (INN), a drug used to treat severe acne, has anti-inflammatory and antibacterial properties. INN may affect periodontal pathogenic bacteria, so we aimed to study the effect of INN on intraoral microbial profiles of periodontal disease and healthy periodontium. Our case-control study divided 180 subjects into six groups according to periodontal health status and INN usage as follows: healthy periodontium receiving INN (HINN; n = 30); those with generalized plaque-induced gingivitis receiving INN (GINN; n = 30); and those with stage I generalized periodontitis receiving INN (PINN; n = 30). Subjects not taking INN, were categorized in the same manner: those with a healthy periodontium (HC; n = 30); those with generalized plaque-induced gingivitis (GC; n = 30); and those with generalized periodontitis stage I (PC; n = 30). Plaque samples were collected to determine the prevalence of four periodontal pathogens (Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, and Fusobacterium nucleatum) in each study group using real-time polymerase chain reaction. Data were analyzed using IBM SPSS software, and multiple regression analysis was performed for each parameter tested in each group at a significance level of 0.05. All INN groups showed significantly lower levels of P. gingivalis, T. forsythia, and T. denticola and higher levels of F. nucleatum (p < 0.001). INN had an observable antimicrobial effect on the periodontal pathogen count in patients with plaque-induced gingivitis and chronic periodontitis. INN may have a potential additive antimicrobial value in the treatment of periodontal disease.

The Relationship Between Periodontal Disease and ABO Blood Groups: A Cross-Sectional Study.

PURPOSE: The objective of this cross-sectional study was to evaluate the relationship between ABO blood groups and periodontal diseases. MATERIALS AND METHODS: Four hundred sixteen subjects (223 females, 193 males) were recruited according to the eligibility criteria. Periodontal examination was performed, including full-mouth plaque index (PI), bleeding on probing (BOP), clinical attachment level (CAL), and interproximal bone loss (IBL). ABO blood group patterns were determined based on self-reports, confirmed by medical records. The chi-squared test was done to evaluate the data (p < 0.05). RESULTS: Out of the 416 subjects, 52.2% were blood group O, whereas 27.8% were blood group A. 46.8% of patients with blood group O had gingivitis and 49.6% had periodontitis. 31.2% of patients with blood group A had gingivitis,while 29.5% had periodontitis. The blood group with the lowest percentage among patients with gingivitis was AB, with a rate of 6.2%; in this blood group, 8.1% had periodontitis. CONCLUSIONS: There is no association between periodontal diseases and ABO blood group types.

Short-term improvement of clinical parameters and microbial diversity in periodontitis patients following Indocyanine green-based antimicrobial photodynamic therapy: A randomized single-blind split-mouth cohort.

BACKGROUND: Indocyanine green-mediated photodynamic therapy is effective against chronic periodontitis. Here, we evaluated the efficiency of indocyanine green-based adjunctive antimicrobial photodynamic therapy in non-surgical treatment of chronic periodontitis patients. METHODS: Fifty-six periodontally involved teeth of 20 patients were treated with "scaling and root planing" (control group) or "scaling and root planing with indocyanine green-based (perio-green, 0.1 mg/ml) antimicrobial photodynamic therapy" (test group) using a split-mouth design. We performed clinical assessment of probing depth, gingival recession, clinical attachment loss, and other indices, while plaque samples were collected for microbiome analysis. RESULTS: At baseline, periodontal depth and clinical attachment loss were significantly higher in the test group (p < 0.05), and at 1-month post-treatment, we observed a significant favorable reduction of both periodontal depth and clinical attachment loss in test and control sites, with lower means maintained at 3 months (p = 0.01 and p = 0.000, respectively). Additionally, analysis of variance showed significant improvements in periodontal depth and clinical attachment loss in the indocyanine green-antimicrobial photodynamic therapy group (p = 0.001), although not for clinical attachment loss in controls (p = 0.102). Moreover, a significant reduction was observed in test sites for bleeding on probing and residual pocket post-therapy (p = 0.04 and p = 0.0001 respectively). Furthermore, microbiome analysis identified Porphyromonons gingivalis, Treponema, and Tannerella in all samples with favorable changes in test sites (p = 0.07). CONCLUSION: We observed a significant reduction in periodontal clinical parameters (periodontal depth and clinical attachment loss) in chronic periodontitis patients treated with antimicrobial photodynamic therapy as an adjunctive procedure to conventional scaling and root planing. This improvement was associated with periodontal pathogen reduction and increase in the healthy subgingival microbiome.

Dental implant primary stability in different regions of the Jawbone: CBCT-based 3D finite element analysis.

AIM: This study aimed to analyze the primary stability of dental implant in maxillary and mandibular anterior and posterior regions using a finite element analysis. MATERIALS AND METHODS: CBCT images of maxillary and mandibular regions were collected from patients' radiographic data and transformed to 3D models. A Straumann Dental implant was inserted in each bone model and then pulled-out, where amount von-Mises stress was obtained and analyzed for each. A comparison between the insertion and the pull-out was evaluated. RESULTS: Twenty-four images were randomly selected for analysis from 122 scans. In both the insertion and the pull-out of the dental implant, von-Mises stress was high in cortical as compared to the cancellous bone (p < 0.0001). Maxillary posterior region had a low von-Mises stress (p < 0.001). Bone plastic deformation was higher in cancellous than the cortical bone in all bone regions and was the lowest in maxillary posterior region (p < 0.001). Bone displacement decreased from Type I to type IV bone. CONCLUSION: Evaluation of von-Mises stress showed different measurements in maxillary and mandibular regions. Bone deformation was low in the maxillary posterior region.

Effects of Clinical Training and Case Difficulty on the Radiographic Quality of Root Canal Fillings Performed by Dental Students in Saudi Arabia.

INTRODUCTION: The aim of this study was to evaluate the effects of training duration and case difficulty on the radiographic quality of root canal fillings performed by dental students in Saudi Arabia. METHODS AND MATERIALS: A longitudinal cohort study was conducted at King Saud University. Root canal treatments performed by 55 dental students from 2012-2014 were included in the study. Each student treated at least five teeth during the first year of clinical endodontic training and another five teeth during the second year. Case difficulty was assessed based on tooth position in the dental arch and preoperative conditions. The radiographic quality of the root canal filling was evaluated by two endodontists blinded to treatment completion date. The evaluation criteria were adequate obturation, presence of mishaps and preparation taper. The data were statistically analysed using univariate and multivariate logistic regression analyses; and the level of significance was set at 0.05. RESULTS: Inadequate obturation and mishaps were significantly less prevalent in teeth treated after 2 years of clinical training. The odds ratios for inadequate obturation and mishaps increased significantly as tooth position moved posteriorly. Inadequate obturation and more mishaps were significantly more prevalent in teeth with preoperative conditions. Preparation taper was not significantly affected by training duration or case difficulty. CONCLUSION: The quality of root canal fillings performed by Saudi students was adversely affected by case difficulty. The radiographic quality of root canal fillings improved significantly after 2 years of clinical training. Preparation taper outcome is likely dependent on the preparation technique and instrument taper.