Tikrit Journal for Dental Sciences

Background: Orthodontic mini-screws (OMSs), also known as
temporary anchorage devices (TADs), are essential for managing
complex malocclusions. However, the use of traditional
materials, such as titanium and stainless steel, has restrictions that
include stress shielding, aesthetic limitations, and incompatibility
with various imaging modalities. Poly-ether-ether-ketone (PEEK),
a biocompatible thermoplastic polymer, possesses mechanical
properties close to that of bone and therefore presents an excellent alternative.
Objective: To assess the suitability of PEEK as a material for OMSs, outline benefits of PEEK compared with metallic counterparts, and identify gaps in current research.
Methods: An existing literature search was performed, utilizing internet sources, such as Google Scholar and PubMed, focusing on properties, dental and orthodontic applications of PEEK.
Conclusion: PEEK’s favorable biomechanical compatibility, radiological advantage, and existing success in other dental applications make it a potential candidate for OMSs. However, there is a remarkable lack in studying the possibility of PEEK based OMSs. Further research is needed to confirm their performance trends, optimize design parameters, and set guidelines for incorporation in the field of orthodontics.

Background: Polymethyl methacrylate (PMMA) is the most prevalent denture base material; yet, it undergoes dimensional changes due to polymerization shrinkage, water absorption, and temperature cycling, potentially undermining fit precision and clinical efficacy. Recently, the use of nanoparticles to strengthen materials has been suggested as a way to improve dimensional stability.
Objective: To assess the impact of integrating various nanoparticles into PMMA-based denture base materials, encompassing traditionally heat-cured, 3D-printed, and CAD/CAM-milled resins, on dimensional stability.
Materials and Methods: Research articles released from 2015 to 2025 were retrieved from PubMed, ScienceDirect, and Google Scholar. Only studies that evaluated dimensional changes as a primary outcome subsequent to nanoparticle incorporation were considered. Following the application of inclusion and exclusioncriteria, 28 studies were examined.
Results: The majority of experiments demonstrated that nanoparticle reinforcement, namely zirconia nanoparticles (ZrO₂) at 1–3 wt.%, diminished polymerization shrinkage and enhanced dimensional stability in comparison to unmodified PMMA. 3Dprinted resins showed more dimensional changes at first, but these changes were lessened when nanofillers were introduced. CAD/CAM-milled PMMA had the best dimensional accuracy, although it is still more expensive and less adaptable in clinical settings.
Conclusion: Adding 1–3 wt.% ZrO₂ nanoparticles provide the best balance of cost, performance, and dimensional stability. Nanofiller-reinforced 3D-printed denture base materials show promising results, but standardized long-term investigations are necessary to validate their clinical relevance.

When a silicone maxillofacial prosthesis is no longer clinically useful after 1.5 to 2 years, a new prosthesis should be made. Adding some kinds of nano-oxide fillers could enhance the situation and address this issue. This study sought to determine how the CaCo3 nanofiller affected the maxillo facial tear strength of Silicone elastomer RTV50F after artificial aging for 200 hours. Eighty samples in total were split into two groups, each of which having 40 samples, which are then subdivided into four groups: the control group, 0.5%, 0.75%, and 1%. Samples in the prior concentration groups were subjected to rip strength tests both before and after 200 hours of artificial aging. ANOVA and Tukey\'s HSD tests were used to analyze the data and determine the differences among groupings. Scanning electron microscopy (SEM) and Fourier-transform infrared (FTIR) analysis also used. The ANOVA test show Both before and after aging, the silicone elastomer\'s mechanical quality (tear strength) was enhanced by the inclusion of CaCo₃ nano-particles. The best results were obtained at a concentration of 1% CaCo₃ (D group), the efficiency of CaCo₃ in reinforcing silicone is supported by these data. The results showed that the addition of CaCo3 to VST-50F silicone showed significant difference compared to the control group. Finally, one can draw a conclusion stating that the addition of calcium carbonate (CaCo3) nano particles as filler improves and increase the tear strength of silicone elastomer both before and after being artificially aged for 200 hours.

Background: The serviceability of a relined prosthesis is adversely affected by repeated de-bonding of the soft liner from the denture base resin. Aim: to evaluate the bond strength between the denture bases and commercially available soft liners when using different surface treatments.
Material and method: An extensive systematic review was conducted across databases such as PubMed, Google Scholar, and Scopus, involving all articles from January 2011 to June 2024. The 110 records from the research search were screened, resulting in the exclusion of 30 duplicates and 38 papers that did not meet the inclusion criteria of the current study. Twelve were excluded because they were not downloadable for analysis. Thirty-one articles meeting the requirements were identified for full review.
Result: Using database searches, 110 articles were first found. Of these, 31 satisfied the requirements for qualitative analysis. Nine out of twelve articles reported that laser preparation of denture base resins improved their adhesion to soft liners. Six studies concluded. According to six out of seven studies, monomer treatment strengthened the liner-resin connection in the liner. According to six out of seven trials, monomer treatment strengthened the liner-resin connection. According to four investigations, binding strength was also enhanced by the acidetching procedure.
Conclusions: The tensile test has been frequently used in assessing the adhesive bond strength between the denture base and soft liner. Several types of surface pretreatments, including laser, air abrasion, silica coating, acid etching, and monomer treatment, have been developed to enhance the adhesion between soft liners and denture base resins.

Background: Ceramics are biocompatible materials and can simulate the visual character of the tooth substance successfully. Zirconia crowns and lithium disilicate crowns, specifically Emax, are the most highly regarded types of dental crowns.The oral environment is influenced by the all-ceramic restoration system's bond strength. This investigation aimed to determine how surface treatment and core material (Emax- press) affect various ceramic materials' resistance to fracture.
Methods Forty specimens constructed using the heat press method and E-max press material depending on their surface treatment, samples were divided into four groups at random;each group consists of ten samples.Control group:Untreated surface samples.Group sand plast (AL2O3) : aluminum oxide particles are used to sandblast samples.Group potassium hydrogen difluoride (KHF2) : potassium hydrogen difluoride-etched samples.Combination of Group E-max press: samples are etched with potassium hydrogen difluoride and sandblasted with aluminum oxide particles.Using a scanning electron microscope, the morphological change of the E-max press after surface treatment was observed.Every sample has 2mm veneering ceramic applied to it.A universal testing machine was used to measure fracture resistance.
Results: According to data analysis, the (E-max Combination) group had the lowest mean fracture resistance values, while the (E-max sand blast) and (E-max etching) groups had the greatest mean values.
Conclusion: Within the limitations of this study, the results suggest that, utilizing of various surface treatments with E-max press substructures were more effective on the values of fracture resistance.

Background: Complete root canal filling material removal throughout the retreatment is essential for effective disinfection and long-term treatment success. Bioceramic-based sealers, while offering excellent sealing and biocompatibility, are difficult to remove due to their chemical bonding and deep dentinal tubule penetration. Chelating agents such as 17% EDTA can dissolve the inorganic smear layer, and ultrasonic activation has been proposed to enhance its cleaning performance.
Aim: To evaluate the effectiveness of ultrasonic activation of 17% EDTA in removing bioceramic sealer remnants compared to EDTA without activation and file-only retreatment.
Materials and Methods: A total of 30 extracted human mandibular premolars have been prepared, obturated with a bioceramic sealer, and incubated for four weeks. The specimens have been allocated randomly to three groups (n = 10 each): Group1 – 17% EDTA with no ultrasonic activation; Group2 – 17% EDTA with ultra-sonic activation; Group3 – control (files only). Retreatment has been performed with the use of ProTaper Universal Retreatment files. In Groups 1 and 2, EDTA has been delivered with a 30-gauge side-vented needle; in Group2, ultrasonic activation was applied for 20 seconds initially and 30 seconds during final irrigation. Samples were sectioned, imaged under SEM at coronal, middle, and apical thirds, and analyzed using ImageJ to quantify the percentage of uncleaned surface area. Data had been evaluated with the use of Shapiro–Wilk and one-way ANOVA tests (p < 0.050).
Results: Mean residual debris was 39.8% ± 2.5 (EDTA + ultrasonic), 47.3% ± 2.8 (EDTA alone), and 65.2% ± 3.1 (control), showing significant differences (p < 0.001).
Conclusion: Ultrasonic activation markedly enhanced sealer removal, especially in the apical third, improving overall canal cleanliness.

Aim:This study aimed to estimate the effect of different obturation techniques using a Guttaflow2 sealer on the amount of residual filling material at the apical region after retreatment, focusing on factors such as canal cleanliness, residual material quantity, and ease of retreatment
Method:Thirty fresh extracted human mandibular premolar teeth were used in this study. Afterwards the preparation of the root canals using hand protaper technique to F3, the teeth were divided into three groups with 10 sample in each group. G1 obturated with single cone technique, G2 obturated with Lateral Condensation, and G3 was obturated with Soft Core. Guttaflow2 sealer was used After the incubation period of two weeks, obturation materials in all samples were removed using the ProTaper Universal Retreatment files D1, D2, and D3. all procedure was done in vantom lab in the collage of dentistry/ mustansiriyah university. After mechanical removal, use ultrasonic activation with 5.25% NaOCl for 60 seconds to enhance sealer dissolution. Final irrigation with saline to ensure thorough cleansing. Then, the samples were split longitudinally and examined by a digital stereomicroscope at 12.5X magnification. and the examination of samples done in the Department of Materials Engineering, University of Technology After that, the remnants of root-filling materials at apical area were calculated as a percentage at 3mm from the apical foramen.
Results: The ANOVA test revealed no statistically significant difference between the mean values of G1, G2, and G3 (p > 0.05). Higher percentages of unfilled areas were observed in Group 2, followed by group3.
Conclusion: The retreatment technique used was incapable of complete removal of filling material within root canal walls, especially at the apical region

Background: There is a growing need for prosthetic materials that combine mechanical strength with biological integration.
Aim: This in vitro study investigates the synergistic effect of incorporating nano-hydroxyapatite (n-HA) and chitosan nanofibers (ChNF) into poly ether ether ketone (PEEK) to enhance its performance for fixed dental prostheses.
Materials and Methods: In the department of Orthodontics at University of Misan College of Dentistry in Iraq, this in vitro experimental study was conducted. PEEK was reinforced with 5 wt.% n-HA and 1 wt.% ChNF using melt blending and compression molding. Flexural strength and surface roughness were evaluated and compared with unmodified PEEK.
Results: The reinforced PEEK specimens showed a statistically significant increase in flexural strength (153.4 ± 5.6 MPa vs. 127.8 ± 4.9 MPa, p = 0.002). Surface roughness increased slightly (0.31 ± 0.06 µm vs. 0.23 ± 0.04 µm) but remained within clinically acceptable limits (p = 0.21).
Conclusion: Incorporating n-HA and ChNF into PEEK is apromising strategy to improve the mechanical and bio functional properties of prosthetic materials.

Background: Osseointegration is the intimate biological connection between bone and a load-bearing implant which is the cornerstone of modern implant dentistry. When bone volume or quality is inadequate, graft materials are required to reconstruct the alveolar ridge and provide a stable host bed. Over the past three decades, xenografts, alloplastic substitutes, bovine-derived matrices, and coral-based scaffolds have been explored as alternatives to autogenous bone. In light of these developments, the present review synthesizes experimental and clinical evidence to elucidate the biological phases of osseointegration, establish measurable success criteria, and compare the biological behavior, strengths, and limitations of the four major graft categories, while further highlighting preventive strategies to reduce biological and mechanical complications. Methods: PubMed, Scopus, and Web of Science, 1980-April 2025, were searched to conduct the systematic narrative review. Keywords were osseointegration, dental implant, xenograft, bovine graft, alloplastic graft and coral graft. The inclusion criteria were restricted to peer-reviewed studies with English language reporting histological, radiographic or biomechanical outcomes. Results: Long-term dimensional stability was provided by xenograft and bovine materials, remodeling was slowed; alloplastic grafts were found to turnover more quickly and have higher early bone formation; coral-derived scaffolds were found to provide natural porosity but have limited mechanical strength. When properly handled all materials were biocompatible. Conclusion: The graft classes have a unique role to play in bone regeneration. Effective osseointegration requires balancing between material properties and defect morphology, precision of surgery and host healing. There is still necessity of standardized long-term studies with the aim of perfecting the material choice.

This in vitro study evaluated the effects of different polishing protocols on the microhardness and surface topography of multilayered (ML) and monolithic (MZ) yttria-stabilized tetragonal zirconia polycrystals (Y-TZP) used in fixed dental restorations. The objective was to compare the influence of manual and semi-automatic polishing methods on both mechanical performance and surface quality, aiming to identify the most effective protocol for clinical application. Eighty discshaped zirconia specimens were prepared and divided into eight groups (40 MZ: A1, B1, C1, D1; and 40 ML: A, B, C, D) according to polishing protocol. Groups A and A1 served as controls, manually polished with a zirconia laboratory kit. Groups B/B1, C/C1, and D/D1 were polished semi-automatically using a grinder-polisher with 3 µm polycrystalline diamond suspension, 6 µm polycrystalline diamond suspension, and 0.04 µm colloidal silica, respectively. Microhardness was measured using a Vickers microhardness tester, and surface topography was examined via scanning electron microscopy (SEM). Statistical analysis was performed using one-way ANOVA and Tukey’s post hoc test. Significant differences in microhardness were found among polishing methods for both zirconia types (p < 0.001). Groups C (1494.84 VHN) and C1 (1493.98 VHN) achieved the highest hardness values, while the control groups A (1378.42 VHN) and A1 (1376.13 VHN) recorded the lowest. SEM revealed that D/D1 exhibited the smoothest and most uniform surfaces, whereas A/A1 showed deep grooves. Findings indicate that semiautomatic polishing with 6 µm diamond maximizes hardness, while colloidal silica provides superior smoothness, guiding clinical selection for optimal zirconia restoration outcomes.

Background: Periodontitis is a chronic inflammatory disease affecting the periodontium. Its impact on systemic health has been proved. Therefore, early detection of this disease is crucial. However, periodontitis is known to be a silent disease in early stages. Patients usually are unaware of their periodontal health status.
Aims: This study aimed to identify the most common chief complaints of patients attending a periodontal clinic and compare these complaints to the clinical diagnosis of periodontitis and gingivitis.
Methods: This cross-sectional study investigated dental records of patients attending a university periodontal clinic. Chief complaints of the patients were divided into groups including halitosis, bleeding gums, pain, and discomfort. These complaints were compared to the clinical periodontal condition of the patients. X2 test, regression, and decision tree analyses were performed.
Results: A Total of 520 dental records were assessed. 202 (38.8%) of the patients attended for check-up with no complaints. Half of them had healthy periodontium. Of patients complaining of pain or discomfort, 65.5% had periodontitis (x2 p-value=0.001). Additionally, half of the patients who complained of bleeding gums were diagnosed with periodontitis, however, this was not statistically significant (x2 p-value=0.065). The decision tree analysis showed that young age (≤29 years) non-smoking patients with periodontal disease were more likely to complain of bleeding gums (15 out of 23 (65.2%)),
Conclusion: This study showed that young patients with periodontal disease were complaining from pain and discomfort, and bleeding gums among non-smoking patients. This can help in increasing the awareness of periodontal disease among young population to seek professional care early to prevent periodontal destruction.