Journal of Baghdad College of Dentistry

Background: Polymethyl methacrylate (PMMA) resin is extensively utilized in
prosthodontics and orthodontics, particularly in fabricating artificial teeth, provisional crowns,
denture bases, and orthodontic retainers. Aims: This study aimed to evaluate the effects of
incorporating cerium oxide and polyether ether ketone nanoparticle (CP) composite into PMMA
resin on transverse strength, impact strength, surface hardness, and denture base adaptation.
Materials and Methods: A total of 120 PMMA specimens were divided into three groups based on
the concentration of CP composite added to PMMA resin, with each group consisting of 40
specimens: a control group without fillers, group (A) containing 1% wt. of composite filler with a
ratio of 30% cerium oxide and 70% polyether ether ketone, and group (B) comprising 3% wt. of
composite with a ratio of 50% ceria, and 50% polyether ether ketone, as determined by the pilot
study. Each group was tested for transverse strength, impact strength, surface hardness, and
denture base adaptation, with 10 specimens for each test. The tested specimens were examined
using Fourier transform infrared spectroscopy (FTIR), and field emission scanning electron
microscopy (FE–SEM). The resulting data were statistically analyzed using SPSS at a significance
level of P≤0.05. Results: Group B showed a significant statistical increase in transverse and impact
strength compared with the other groups. Surface hardness and denture adaptation increased
significantly in group A. FTIR analysis revealed transmission peaks and heightened intensity after
the addition of the CP composite into the PMMA. The FE–SEM images showed a well-distributed
nano CP composite within the PMMA matrix for all experimental groups, with increased
agglomeration observed in group B (3%). Conclusion: The incorporation of 3% wt. CP into PMMA
resin significantly improved transverse and impact strength compared with 1% wt. and the
control. The surface hardness and denture base adaptation improved when 1% wt. CP was
incorporated into the PMMA resin compared with the other tested groups.

Abstract: Background: This study aimed to assess the impact of topical kappa￾carrageenan gel on alleviating Burning Mouth Syndrome (BMS) symptoms in type 2 diabetic
patients and to assess its impact on salivary immunoglobulin A (IgA) and alpha-amylase
levels. Material and methods: 156 participants were included 104 type 2 diabetic patients with
BMS (52 males, 52 females) and 52 healthy controls. Diabetes diagnosis was confirmed
through fasting blood glucose and HbA1c tests. BMS diagnosis was established clinically,
using criteria and laboratory tests to exclude other causes. Kappa carrageenan gel was
prepared and applied topically to relieve BMS symptoms. Unstimulated whole saliva samples
were collected to measure salivary IgA and alpha-amylase levels using enzyme-linked
immunosorbent assay. The collection of saliva was conducted at two different time points for
the BMS group and once for the controls. Results: Application of carrageenan gel showed no
significant effect on salivary IgA levels in diabetic BMS patients. However, there was a
significant reduction in salivary alpha-amylase levels after carrageenan gel application,
indicating a possible response to treatment. Conclusions: Kappa carrageenan gel may serve
as a potential therapeutic option for relieving the burning sensation and pain associated with
BMS in patients with type 2 diabetes. While the gel did not influence IgA levels, the significant
reduction in salivary alpha-amylase suggests an impact on stress-related salivary biomarkers,
supporting its symptomatic relief potential in managing BMS in diabetic patients.

Abstract: Background: Cephalometric analysis is essential in orthodontic diagnosis and
treatment planning. With the increasing use of artificial intelligence (AI) in clinical practice,
automated platforms such as WebCeph have been introduced; however, their accuracy and
reliability across different types of measurements remain a concerns. Objectives: evaluate the
agreement and reliability between skeletal and dentoalveolar cephalometric measurements
obtained using an AI-based platform (WebCeph) and digital manual tracing performed with
AutoCAD.Materials and Methods: A total of 100 lateral cephalograms were analyzed using
WebCeph (AI-driven software) and digital manual tracing in AutoCAD. Fourteen Steiner and
Tweed variables were selected and categorized into skeletal and dentoalveolar measurements.
Statistical comparisons were performed using paired t-tests or Wilcoxon signed-rank tests,
depending on data distribution. Agreement between the two methods was assessed using
intraclass correlation coefficients (ICC) and Bland–Altman analysis. Conclusion: Overall
agreement between WebCeph and AutoCAD was good for most variables (ICC ≥ 0.75). Skeletal
and dentoalveolar measurements showed comparable reliability, although skeletal
measurements demonstrated slightly smaller mean differences and narrowerlimits of agreement.
Greater variability was observed in dentoalveolar variables, particularly those related to
mandibular incisor inclination. Conclusion:WebCeph provides clinically reliable cephalometric
measurements and can be considered a supportive diagnostic tool. However, selective manual
verification is essential.

Abstract: Background: The materials and techniques of orthodontic bonding
systems remain a pivotal concern in orthodontic research. This issue is further
complicated by orthodontists' preferences. To assess the effect of knowledge and
practice on the attitudes of orthodontists towards bonding materials and techniques.
Methods: A cross-sectional, questionnaire-based study was conducted using Google Forms.
The questionnaire comprised 17 multiple-choice questions that targeted orthodontists'
awareness, knowledge, and attitude towards bonding materials. It was distributed via email
or social networking platforms to specialist Iraqi orthodontists. Results: A total of 176
participants responded with nearly equal representation between the sexes. The majority of
respondents (approximately 70%) held an M.Sc. degree, and slightly more than half the
sample worked in both governmental and private clinics. All participants were aware of the
etch and rinse adhesive system, and the majority used it with light curing as the activation
method. The effect of academic degrees and place of work was evident in some responses
related to the selection and management of bonding adhesive. Conclusions: The
orthodontists preferred the traditional etch and rinse technique to minimise bracket loss and
maintain treatment flow. The self-etch primer system was the preferred option when
prioritising safety, time efficiency, reduced technique sensitivity, and aerosol reduction.
Clinical choices may be significantly shaped by skills and information from initial training,
despite the available evidence-base. Future decision-making should prioritise leveraging
scientific evidence effectively.

Abstract: Background: Oral cancer is a major problem in dentistry and remains a major
global health issue. In oral cancer, BCL-2, which plays a role in regulating cell death, is
overexpressed, thus leading to its progression and resistance to chemotherapy. Clausena
excavata contains a coumarin called nordentatin, which has been shown to have anticancer
properties. Particularly with regard to its function as a BCL-2 inhibitor, the underlying
molecular mechanism is yet unknown. Objectives: The aim of this study was to determine the
potential of nordentatin as a BCL-2 protein inhibitor through molecular docking and then
validate it with molecular dynamics. Materials and Methods: Nordentatin\'s ADMET and
bioactivity were estimated in silico. AutoDock Vina was used for molecular docking against
BCL-2 using methotrexate as a comparison ligand and venetoclax as a reference ligand.
PyMOL and Biovia Discovery Studio were then used for interaction analysis. Complex
stability was assessed using a YASARA molecular dynamics simulation. Results: Nordentatin
exhibits potential as an anti-inflammatory, anti-angiogenic, antioxidant, and anticancer drug
based on bioactivity predictions. ADMET analysis showed that this compound is readily
absorbed in the intestine, has moderate clearance, limited penetration into the central nervous
system, and low toxicity, thus indicating a favorable pharmacokinetic and safety profile.
Molecular docking results show that nordentatin has a fairly strong binding affinity for BCL-
2 with a value of −7.4 kcal/mol, which is mainly influenced by hydrophobic and electrostatic
interactions. Molecular dynamics simulations indicate that the BCL-2–nordentatin complex
remains stable, with an RMSD value below ±2 Å, a compact Rg profile, and favorable RMSF
fluctuations. Conclusion: The results indicate that nordentatin binds strongly and stably to
BCL-2, thus offering potential for development as a BCL-2 inhibitor for oral cancer therapy.

Abstract: Background: Laser irradiation has been widely utilized in the modification of
material surfaces by altering their microstructure and topography, however, the effect of
irradiation parameters such as power output and beam angle to bonding performance of
metallic substrates remain insufficiently understood, especially for Ni-Cr metals. Objectives:
This study aimed to evaluate the effects of diode laser power in different beam angles on the
surface of Nickel-Chromium (Ni-Cr) metals to improve bonding strength of adhesive bridge.
Materials and Methods: Thirty-six cylindrical Ni-Cr metals, with a thickness of 2.0-3.0 mm,
and 36 post-extraction maxillary premolars were divided into 6 groups (n=6). A diode laser
irradiation was performed on metal samples with beam-angles of 30°, 60°, and 90° and powers
of 2.0 watts and 4.0 watts. Teeth were then cemented into metal samples using resin cement.
After treatment, shear-bond strength (SB-Strength) testing was carried out using a Universal
Testing Machine (UTM). Meanwhile, the samples also were evaluated using Scanning
Electron Microscope (SEM) and Atomic Force Microscope (AFM). Data were analyzed using
a T-test, ANOVA test, and LSD test. Results: A significant SB-strength was found in 30° for
2.0 watt and 90° for 4.0 watt respectively 4.48±1.97 MPa and 5.27±2.50 MPa. Morphological
analysis suggested that 30° allows more uniform surface roughness, while 90°allows similar
patterns but with higher depth. Conclusion: These results provide practical guidance for
clinicians by indicating that perpendicular laser irradiation (90°) at controlled power settings
may improve bonding reliability in adhesive bridge procedures involving Ni–Cr frameworks