MUSTANSIRIA DENTAL JOURNAL

Background: The effectiveness of implant-supported restorations largely relies on their capacity to resist functional forces. To enhance the mechanical performance of zirconia restorations, different abutment designs have been developed and are currently in use. Aim: This study aimed to evaluate the fracture resistance and fracture modes of implant-supported zirconia crowns fabricated with different abutment configurations after artificial aging. Materials and Methods: 36 implant analogs were arbitrarily assigned to three groups (n = 12). Group A: one-piece hybrid abutment crowns (HAC). Group B: Two-piece restorations hybrid abutment with a separate crown. Group C: stock titanium abutments with crown. Artificial aging was applied to all specimens (500 thermo-cycle and 120,000 mechanical cyclic). The fracture resistance was assessed by a universal testing machine, the fracture modes were evaluated under (SEM) at ×30, ×300, and ×5000 magnifications. Results: Group A showed the highest fracture resistance mean (2243.2 ± 234.2N), Group B recorded the lowest value (1819.6 ±173.2 N). The difference among the groups was statistically significant (P < 0.05). SEM analysis revealed different fracture morphologies in the three different groups. Conclusion: The one-piece restoration revealed highest fracture resistance. However, the fracture resistance values in the different designs were higher than the average masticatory forces in the premolar teeth, supporting their potential for clinical use.

Aim: This narrative review was an attempt to assess the impact of plasma surface treatment on Polymethyl methacrylate (PMMA) heat-cured acrylic resin with special attention on surface properties and antimicrobial activity. Methods: The PRISMA method was used to identify literature in PubMed, Google Scholar, and Research Gate databases. Articles published from January 2016 to March 2025 that explored the topic of plasma surface treatment of heat-cured acrylic resin were taken into consideration. Out of the 183 studies found, 32 studies were found to meet the inclusion criteria. Results: The analyzed literature proved that Atmospheric Pressure Cold Plasma treatment and Dielectric Barrier Discharge treatment substantially enhanced wettability and surface energy of PMMA based on functional groups polarization incorporation. These changes on the surfaces continuously decreased adhesion of microbes, especially Candida albicans, and prevented the formation of biofilms. Moreover, the bond strength between PMMA and soft liners, coatings and adhesives, was improved through plasma treatment. These effects differed in their magnitude with parameters of plasma (gas type, exposure time, etc.) Conclusion: Plasma surface treatment can be a promising technique of enhancing biofunctionality and longevity of heat-curing PMMA dentures. Nonetheless, it requires standardized treatment regimens and long-term clinical trials that can establish its clinical reliability.

Objectives: This study focused on comparing the marginal fit of crowns made of zirconia and lithium disilicate, using two types of preparation designs (vertical feather edge, horizontal shoulder) for both cemented and non-cemented situations. Methods and Materials: Forty maxillary premolars (all extracted) were randomly assigned to one of two groups based on material type: Lithium Disilicate (Group A) and Monolithic Zirconia (Group B). Within each of these groups, the teeth were further divided into two subgroups based on margin design: Feather Edge and Shoulder Preparation Designs (n=10). All specimens had standardized preparations performed with the aid of a modified dental surveyor, followed by digital scans. For the Crown (s) & Processes created by ExoCad and constructed via Pressing Technique (Lithium Disilicate) and Milling Technique (Zirconia), the preparation margins were evaluated pre -& Post Cementation via digital microscopy at 40x magnification at each Specimens Marked 16 Standardized locations using ImageJ Software. All standardized evaluations were subjected to: Two-Way ANOVA, Tukey HSD, AND Paired 't-test' statistical analyses. Results: After cementation all groups exhibited more of a marginal gap. The groups with vertical preparations A1 and B1 had a significantly less marginal gap compared to groups with horizontal preparations A2 and B2 prior to and following cementation. Group A1 had the least amount of gap and therefore exhibited a more favorable marginal adaptation of the lithium disilicate when using a vertical preparation than did groups A2, B1, and B2. There were significant differences between groups according to statistical analysis (p < 0.05). Conclusion (Principal Designer): The marginal adaptation of vertically prepared edges (feather edge/preparation) compared to horizontally prepared (shoulder) edges produced significant differences; this was regardless of which type or class of ceramic material used. The findings indicate that by using minimally invasive vertical preparation techniques; the longevity of restorations and their fit can be greatly enhanced.

Objectives of the study: This research aimed to assess levels for salivary trace elements, iron and copper as potential biomarkers for dental caries in Iraqi patients. Methods: Stimulated salivary samples were collected from 60 participants aged from (20-27) years divided into two groups, first group (patients with cavitated D2 enamel-dentine caries) and the second group (control patients with initial enamel caries but not cavitated lesions) to determine iron and copper concentrations. Results: There had been a significant elevation of salivary iron and copper in caries group (p<0.001). There was a positive relationship between iron and DMFT scores (r = 0.3, p = 0.03). ROC analysis revealed that iron had strong diagnostic performance (AUC=0.9), while copper showed moderate accuracy (AUC=0.7). Conclusion: Salivary iron demonstrated high sensitivity and specificity for detecting dental caries and may serve as a reliable biomarker. Copper may also be supportive but less specific. These finding suggested that the diagnostic accuracy of salivary trace elements, though further standardized collection methods of saliva are recommended.

Aim: To determine the knowledge, attitude and practice of dental students regarding oral halitosis and associated gender differences at Mustansiriyah university-college of dentistry. Methods: A cross-sectional study design was used in Baghdad, Mustansiriyah University- college of dentistry and a total of 136 students participated in the study. A standardized questionnaire that was self-administered was used to collect data on socio-demographics, oral halitosis knowledge, attitudes, and practices. After being examined and cleaned, the data was imported into SPSS version 25.0. The data was described using descriptive statistics, and the results were shown in tables and texts. Results: A total of 136 undergraduate dental students were assessed on the perception of halitosis. In terms of knowledge, the overall participants had satisfactory knowledge toward halitosis (62.8%). The participants demonstrated a favorable attitude toward halitosis, with an overall attitude score of 87.3%. The overall level of practice toward halitosis was low (23.3%). The students’ gender demonstrated a statistically significant association with selected items only; specifically in one knowledge question and two practice questions, whereas no significant gender-related differences were detected across any of the attitude items. The overall association between knowledge and practice was weak to moderate. Conclusion: The study concludes that the overall knowledge about halitosis was satisfactory with generally positive attitudes. However, the overall practice was low. This highlights the need for focused educational and behavioral interventions and to enhance the practices of oral hygiene. Students' gender did not have an impact on the KAP domain.

Background: Dental caries is a common chronic disease that is intricately associated with dietary sugars and oral microbial activity, especially Streptococcus mutans (S. mutans). The purpose of this study was to compare the impact of Splenda (sucralose) and sucrose on both salivary pH and S. mutans. The aim of the study: The current study sought to comparatively assess the impacts of sucralose (Splenda) and monk fruit, on salivary pH and salivary Streptococcus mutans counts, relative to sucrose, after a standardised mouth-rinse protocol. Methods: Ninety healthy dental students from Mustansiriyah university aged from 20-24 they were randomly grouped into two groups (n=45 each): Splenda, and sucrose.se. Each participant rinsed with 10g of the assigned sweetener dissolved in 90ml of distilled water. Then the unstimulated saliva samples were taken at the start, right after rinsing, and again 15 and 30 minutes after rinsing (the rinsing took one minute). We used a digital pH meter to measure the pH of saliva and serial dilution and culture on selective media to count the number of S. mutans. Results: the findings indicated that sucrose markedly reduced salivary pH over time (p<0.001), whereas Splenda maintained near-neutral pH levels. Additionally, Splenda significantly reduced S. mutans counts (p<0.001), while sucrose increased bacterial growth (p=0.004). Statistically significant differences between the groups were observed at 30 minutes (p<0.001). Conclusion: Splenda have a cariostatic effect by preserving salivary pH and reducing S. mutans, supporting their use as sugar substitutes in caries prevention.

Aim: The study’s aim was to compare the fracture strength of root obturated with AH Plus and AH Plus Bioceramic sealers utilizing different obturation techniques. Materials and Methods: The palatal roots of fifty-six extracted maxillary-first molars were used in this study. All samples were sectioned to keep the root length constant at 11 mm. The roots were instrumented utilizing ‘EdgeFileX7 rotary files to size 40/0.04. Eight-roots were left unobturated as a control-group, while the others roots were divided into two different groups (n=24) based on the sealant used for obturation; AH plus &AH Plus BC. Each group was then subdivided into three-subgroups (n = 8) based on the obturation approach; single-cone, Warm vertical compaction (WVC) and soft-core. All roots were embedded in acrylic-resin blocks, and fracture force was evaluated with universal-testing equipment utilizing a metal-like spreader tip at a rate of 0.5 mm per minute. The results had undergone statistical evaluation using ANOVA and Tukey-test. Results: The fracture-resistance was significantly affected by the ‘obturation-technique’ and by “sealer/obturation technique” interaction. Obturation with AH Plus BC+WVC had the highest mean fracture-resistance value (351.5000 Newtons) while the control-group demonstrated the lowest mean fracture-resistance value (116.3750 Newtons). Conclusion: Obturation using AH plus BC+WVC was more effective combination providing highest fracture root resistance.

Background: Recent developments in manufacturing technology have brought three-dimensional (3D) printing as an efficient method for directly fabricating products from computer-aided design (CAD) data. This technology has attracted much attention in dentistry and is now employed in numerous fields, such as prosthodontics, orthodontics, and implant dentistry. Although there are several studies on the reinforcement of 3D-printed dental resins using nanoparticles, there are still few narrative reviews that provide detailed discussion on the reinforcement tactics and the related manufacturing issues. Purpose: The present study covers the existing information on 3D-printed dental resins, highlighting the use of nanoparticles as a reinforcing method, the possible constraints of incorporating nanoparticles, and the manufacturing processes involved in the production of the materials. Furthermore, the influence of these alterations on the mechanical and physical behavior of printed dental materials is also examined to provide a better understanding of recent advances and possible future avenues of research. Methods: The relevant studies were obtained by studying the articles published in 2010-2025 in the databases of Scopus, Pubmed, and Google Scholar. The inclusion criteria focused on research that evaluated the introduction of nanoparticles in 3D-printed dental resins to enhance mechanical, surface or functional qualities. Inclusion of studies having a defined experimental procedure and quantitative results. Results: The nanoparticles tested were ZrO2, YSZ, SiO2, ZnO, TiO2, Al2O3, and Ag and several mechanical, surface, and antibacterial properties of 3D printed dental resins were improved with minimal, or no change in certain properties.The effect was also found to rely on the type and concentration of the nanoparticles and the preparation and printing processes utilized. But these developments have sometimes led to problems with resin formulation, printing accuracy and post-processing, which have to be carefully calibrated for clinical use. Conclusions: Enhanced some mechanical, surface and antibacterial properties, as well as the potential for function and material development, due to the addition of nanoparticles to the 3D-printed dental resins. More research is needed to fully examine the long-term effectiveness of different types and doses of nanoparticles, their therapeutic significance and any health hazards related with their use.

Background: Bad breath or halitosis is a prevalent issue that adversely effects social life and general well-being. Chlorhexidine is commonly used to manage it, but its prolonged use is associated with undesirable side effects. Natural probiotic alternatives like kefir may help reduce halitosis by restoring oral microbial balance. Aim: This research aimed to investigate the efficacy of kefir mouthwash, a probiotic-based natural alternative, compared to chlorhexidine (CHX) in reducing halitosis Materials and Methods: A triple-blind, randomized, controlled clinical study involved 60 systemically healthy adults whose ages ranged 18-28 years diagnosed with moderate gingivitis, recruited from dentistry students at Bilad Al-Rafidain University and training dentists from a specialized dental center in Diyala, Iraq. Subjects were randomly assigned to either control group (30 subjects) using 0.12% chlorhexidine mouthwash or study group (30 subjects) using kefir mouthwash twice daily for 28 days. Halitosis was assessed objectively via volatile sulfur compound (VSC) levels, concentration, and odor detection distance using a Halimeter, and subjectively using a Visual Analog Scale (VAS) at baseline, day 14, and day 28. Results: Both groups exhibited significant reductions in halitosis parameters over 28 day time (p < 0.001). The kefir group showed slightly greater improvements in VSC concentration, odor detection distance, and VAS scores at follow-up points, although these differences compared to the control group were small. Conclusion: The findings of this study indicate that both kefir and chlorhexidine mouthwashes are effective options for reducing halitosis over the 28-day period. Although the kefir mouthwash led to slightly better improvements, which may be due to its effects on the oral microbiota, these differences compared to the control group were small. Additionally, kefir's good safety and biocompatibility profile imply that it might be an effective natural substitute for people looking for long-term halitosis treatment without the negative side effects of chlorhexidine. Further research with longer follow-up and larger sample sizes is recommended to confirm its efficacy and mechanisms.

Aim of the study: to assess dentists' attitudes and knowledge regarding dental and oral care for patients undergoing cancer treatment. Method: A study was conducted among general practitioners and specialist dentists working in governmental specialist dental centers and dental clinics in hospitals in Mosul City- Iraq. A self-reporting survey was provided, comprising questions related to demographic characteristics and sections evaluating the dentists' attitudes and knowledge about cancer-treated patients. Data were analyzed using Chi-square, ANOVA test, Kruskal Wallis test and Pearson correlation coefficients. Results: a total of 213 respondents. There was no significant relation between demographic characteristics on one side and attitude and knowledge on the other side. Except the mean score of dentists` knowledge was significantly influenced by work experience, P= 0.03. In summation, a positive attitude toward dealing with cancer therapy patients was 55.1%. Dentists' level of knowledge was 52.5%. The dentists with a higher knowledge score had a less positive attitude toward dealing with anti-cancer therapy patients. However, statistically, there was no significant correlation between attitude and knowledge among dentists. Conclusion: Although the dentists had a slightly higher than moderate level of knowledge, they mostly displayed a positive attitude towards the anti-cancer therapy patients. Therefore, an intervention educational program is indicated.

Aim of the study: This study aimed to evaluate the effect of peppermint oil immersion on the surface hardness of polymethyl methacrylate (PMMA) acrylic resin after different immersion periods (1 day, 1 week, and 3 weeks). Materials and methods: Twenty rectangular samples were set up and split up into two groups, each group had 10 samples, first group was immersed in distilled water and second group was immersed in peppermint oil solution. They included three different periods: one day, one week, and three weeks. A daily immersion routine was adhered during these immersion times. This included immersing for eight hours in the immersion solution and then for sixteen hours in artificial saliva, all specimens were tested by hardness tester. The statistical analysis was used for the data and the comparison among all groups was obtained using analysis of variance test (two-way ANOVA-test) among all groups regarding the different immersion solutions in three different immersions periods. Further analysis was used post hoc comparisons Tukey-test to determine where the differences exist among groups at different times. In addition, Student’s t-test was used for comparisons between the two-immersion media at each time interval. Results: The descriptive statistic revealed that there is an increase in surface hardness after immersion in distilled water and peppermint oil for three weeks, as the results of immersion in distilled water after three weeks (74.70) and the results of immersion in peppermint oil after three weeks was (75.10), but the two-way ANOVA indicated there was no significant interaction regarding immersion time of acrylic resin and both solutions, but there was a significant variation was detected regarding to immersion groups across time points. As well as, the Student’s t-test revealed a significant difference was found between distilled water and peppermint oil after 1 day of immersion but there were no statistically significant differences were observed between the two-immersion media after 1 week or after 3 weeks of immersion. Conclusion: Immersion in peppermint oil and distilled water increased the surface hardness of acrylic resin. Hardness increased significantly from 1 day to later immersion times, while a difference between the two media were observed only after 1 day.

Aim of the study: To verify the effect of probiotic tablets on oral health status and to compare their effects on gingival health and potential salivary biomarkers by monitoring the levels of Interleukin-1β (IL-1β) and Matrix metalloproteinases-8 (MMP-8) in saliva of individuals with moderate gingivitis. Materials and methods: A randomized interventional trial was conducted over 28 days, which included 88 healthy male college students aged 18 to 25 years old from Al-Anbar University. The participants have randomly assigned to two groups: study group (A) and control group (B). The gingival health parameter GI has evaluated clinically, and the concentrations of IL-1β and MMP-8 have been quantified in both groups at baseline (0 days), 14 days, and 28 days. Results: GI significantly decreased in study group when compared to the control group. Fuethermore, IL-1β and MMP-8 showed significant reductions only at day 28. Conclusion: Probiotics may improve gingival health by positively affecting the oral flora and regulating the immune system.