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Prevalence of ponticulus posticus in different skeletal malocclusions types in population from northern Iran 
Amineh Oljash, Reza Faraji, Farida Abesi, Maysam Mirzaie, Hoda Shirafkan,
Volume 39, Issue 0 (3-2026)
Abstract
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Background and Aims: Ponticulus posticus is a bony anomaly in the atlas vertebra that may have significant clinical implications, particularly when extreme head movements are required during treatment. The present study aimed to evaluate the prevalence of ponticulus posticus in different types of skeletal malocclusions in the population from northern Iran.

Materials and Methods: In this observational-analytical study, 246 lateral cephalometric radiographs of eligible individuals referred to two oral and maxillofacial radiology centers in Babol, northern Iran, in 2021, were included using convenience sampling and evaluated. Skeletal classification was determined using the ANB angle and Wits analysis. The presence of ponticulus posticus was evaluated across different skeletal classes, genders, and age groups. Data were analyzed using the Chi-square test in SPSS software with a significance level set at 0.05.

Results: Among the total sample, ponticulus posticus was observed in 104 cases (42.3%), of which 62 cases (25.2%) were of the partial type and 42 cases (17.1%) were of the complete type. The prevalence of this anomaly was significantly higher in males than in females (P<0.001). However, there was no statistically significant association between the presence of ponticulus posticus and skeletal class (P=0.222) or age group (P=0.483).

Conclusion: The findings of the present study indicated that ponticulus posticus was a relatively common anomaly, with a higher prevalence in males, and therefore should be taken into consideration. However, this anomaly neither appear to be a result of age-related calcification, nor can be used as a predictive indicator for determining skeletal class type.


The effect of first premolar extractions on overall and anterior Bolton ratios in patients with bimaxillary dentoalveolar protrusion
Amirhosein Rostami, Seyedali Seyedmajidi, Valiollah Arash, Abbas Ramyar, Nima Hedayati Goodarzi, Amirhosein Ghasemi, Reza Faraji,
Volume 39, Issue 0 (3-2026)
Abstract
Background and Aims: Bimaxillary dentoalveolar protrusion (BDP) is a common orthodontic anomaly characterized by protrusive dental arches and lip prominence. Extraction of the first premolars is a frequently employed treatment approach in these patients. However, the effect of this intervention on Bolton ratios-particularly the overall and anterior ratios-remains unclear. This study aimed to evaluate the impact of first premolar extractions on Bolton ratios in patients with BDP.
Materials and Methods: This experimental study was conducted on archived physical models of 34 Class I patients with BDP and functional lip incompetency (>4 mm) accompanied by lip protrusion, available at the Orthodontics Department of School of Dentistry, Babol, in 2024. All patients had a full complement of teeth from the first incisor to the first molar in each quadrant. After digitizing the models, mesiodistal tooth widths and the overall and anterior Bolton ratios were calculated. Digital simulation of first premolar extraction was performed, followed by reassessment of Bolton ratios. Pre- and post-treatment values were statistically compared using paired t-tests in SPSS (significance level set at 0.05).
Results: Among 34 studied casts, 67.6 % belonged to females. The mean overall Bolton ratio decreased significantly from 90.33 ± 2.23% to 87.72 ± 2.39%, and the anterior ratio declined from 78.19 ± 2.96% to 77.85 ± 3.03% (P<0.001). Additionally, 15 patients exhibited residual space post-treatment, primarily in the mandibular arch.
Conclusion: Based on the results of the present study, first premolar extraction significantly reduced both the overall and anterior Bolton ratios in patients with bimaxillary dentoalveolar protrusion. However, the likelihood of residual space—particularly in the lower arch-should be carefully considered during orthodontic treatment planning to ensure long-term stability and success.

Comparison of the effects of different adhesive systems on the bond strength of repaired composite restorations
Sayeh Hamedanchi, Hafez Vahedpour, Solmaz Charmi,
Volume 39, Issue 0 (3-2026)
Abstract
Background and Aims: Repairing existing composite restorations, rather than replacing them entirely, is regarded as a conservative and tissue-preserving approach in restorative dentistry. However, achieving a durable bond between the aged and newly applied composite resin remains a significant clinical challenge. This study aimed to compare the shear bond strength of repaired composite restorations using three different adhesive systems.
Materials and Methods: In this in vitro study, which conducted at the Faculty of Dentistry, Urmia University of Medical Sciences, 60 disk-shaped composite specimens were fabricated with standard dimensions. After undergoing artificial aging (storage in distilled water for 6 months), their surfaces were roughened mechanically using a diamond bur. The specimens were randomly divided into three groups (n=20) and repaired using fifth-generation (Adper Single Bond), seventh-generation (OptiBond All-In-One), and universal (Single Bond Universal) adhesives, followed by the application of new composite. All  specimens were subjected to thermocycling, and the shear bond strength was measured using a universal testing machine. Fracture patterns of the samples were also examined using a stereomicroscope to determine the modes of failure. Data were analyzed using one-way ANOVA and Chi-square tests in SPSS at a significance level of 0.05.
Results: The mean shear bond strengths were 15.22 ± 4.47 MPa for Adper Single Bond, 14.05 ± 4.66 MPa for OptiBond All-In-One, and 13.44 ± 4.68 MPa for Single Bond Universal. No statistically significant differences were found among the groups (P=0.468). Fracture pattern distribution was also not significantly different (P=0.453), with predominantly cohesive or mixed failures observed across all groups. No adhesive failures were observed.
Conclusion: Under standardized surface preparation, none of the tested adhesive systems demonstrated a statistically significant advantage in the shear bond strength between the aged and new composite. Therefore, the choice of adhesive in composite repair procedures can be guided by practical considerations such as product availability, ease of application, and dentist preference.

Assessment of awareness and attitudes of general dentists in Yazd toward digital dentistry: Emphasis on educational needs
Vahid Herandi, Fahimeh Rashidi Maybodi, Fatemeh Karamad,
Volume 39, Issue 0 (3-2026)
Abstract
Background and Aims: Given the rapid growth of digital technologies in dentistry, assessing dentists’ awareness and attitudes toward this transformation is essential. This study aimed to evaluate the awareness and attitudes of general dentists in Yazd-Iran toward digital dentistry in 2025.
Materials and Methods: In this descriptive-analytical study, 135 general dentists in Yazd-Iran were selected through convenience sampling. Data were collected via an online questionnaire including demographic information and the questions related to awareness and attitude. Dat were analyzed using SPSS version 27 and the statistical analysis tests were Mann-Whitney, Kruskal-Wallis, and Chi-square to examine the variables.
Results: A total of 59 men and 76 women with a mean age of 31.92 ± 7.87 years participated in the study. The mean knowledge score was 7.76 ± 2.77 out of 12. Higher knowledge and a more positive attitude were significantly associated with older age, longer work experience, and male gender (P<0.05). Overall, 74.1% of participants were unaware of the well-known CAD/CAM system, 74.8% were unfamiliar with digital implant software, and 60% did not have adequate knowledge of correct application of intraoral scanners. While, 81.5% reported an overall positive attitude, only 11.9% considered their knowledge to be aligned with modern digital technologies.
Conclusion: General dentists demonstrated a moderate level of awareness and the existing knowledge gaps warrant greater attention in both undergraduate and continuing education. Enhancing knowledge among specific groups-such as younger, less experienced, and female dentists—is essential. Significant differences in attitudes were observed according to the age, gender, and years of professional experience.

Detection of SARS-CoV-2 RNA in aerosols of clinical and non-clinical areas of a dental clinic during the post-pandemic period
Mogtaba Bayani, Hadiseh Mohammadi, Behzad Khonsarinejad, Dr. Seyed Hamed Mirhoseini,
Volume 39, Issue 0 (3-2026)
Abstract
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Background and Aims: The SARS-CoV-2 virus, capable of airborne transmission through aerosols, poses a significant challenge in clinical settings such as dental clinics. The use of high-speed instruments, including handpieces and ultrasonic scalers, generates considerable aerosols that, if contaminated, may facilitate infection transmission. This study aimed to detect the presence of the  SARS-CoV-2 virus in the clinical and non-clinical areas of a dental clinic.

Materials and Methods: In this cross-sectional study, 20 air samples were collected from various sections of the Dental School of Arak University of Medical Sciences. Sampling was performed using a pump equipped with a filter for two hours at a flow rate of 5 L/min and a height of 1.5 m above the floor. The samples were transported under a cold chain, the viral RNA was extracted, and then were analyzed using a specific RT-PCR kit.

Results: Out of 20 collected air samples, 3 samples (15%) tested positive for SARS-CoV-2 RNA. Two from clinical departments (restorative and fixed prosthodontics) and one from a non-clinical area
(pre-clinic).

Conclusion: The findings of this study indicated that SARS-CoV-2 RNA was detectable in some air samples from both clinical and non-clinical areas of the dental clinic. These results highlight the importance of strict adherence to infection control protocols across all sections of dental clinics to minimize the risk of airborne transmission.


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