Journal of Dental School

Objective(s): Oral malignancies pose a significant global health challenge. Oral squamous cell carcinoma (OSCC) is the most common oral cancer, yet its prevalence and clinical pattern vary by region, lifestyle, and risk factors. Despite its high burden, especially in Asia, epidemiological data remain inconsistent. This study provided updated insights on oral malignant lesions to inform early detection and optimize treatment approaches. Methods: This cross-sectional retrospective study reviewed oral cancer records at Department of Oral Medicine at Shahid Beheshti University of Medical Sciences, Tehran, Iran over the past 10 years. Demographic, clinical data, and risk factors were analyzed. Obtained data were analyzed using Fisher’s exact test with a statistical significance of P<0.05. Results: Fifty-two oral cancer cases were identified, with a mean age of 59.67 years and a male-to-female ratio of 1:1.26. The average duration of involvement was 26.87 weeks, with the most common chief complaints being swelling, ulceration, and pain, respectively. Exophytic lesions were the most frequently observed clinical manifestation (69.2%), with the tongue being the most common site of involvement. The most common type of oral cancer was OSCC accounting for 71.2% of cases. Notably, only 25% of patients had identified risk factors for oral cancer. Conclusion: The pattern of oral cancer observed in the present study was largely consistent with previous research. Oral cancer may be more prevalent among women in the absence of significant risk factors. Further exploration of cancer risk factors is essential for guiding diagnosis, treatment, and public awareness.

Objective(s): Fracture of endodontic instruments is a common procedure complication with significant ethical implications. The attitudes and judgments of dentists concerning the disclosure and handling of such incidents are essential for ethical practice and patient trust. Methods: A cross-sectional study was performed alongside 361 dental practitioners across the country, utilizing a validated questionnaire to evaluate ethical conduct and regards concerning fractured endodontic instrument. Data were statistically analyzed using the chi-square test at a 5% significant threshold. Results: Among the participants, 85% experienced fractured instrument. Only 41.7% stated that they informed the patient when such an mishap occurred. Among cases with a good prognosis, 52.9% chose to complete treatment without informing the patient. In cases with a poor prognosis, 54.9% informed the patient and referred them to a specialist. Endodontists demonstrated more ethically aligned responses in some scenarios (p < 0.05). Conclusion: A significant portion of dentists are reluctant to report  fractured instrument, particularly in situations with a positive prognosis. This underscores the necessity for enhanced ethical training and consistent protocols regarding patient communication and mishap management.

Objective(s): Dentists have an important role in improving the knowledge of their patients regarding the indications and correct use of mouthwashes. The aim of the present study was to investigate the knowledge of dental students about commonly used mouthwashes for oral health. Methods: This cross-sectional study was conducted on 275 dental students from 8^th to 12^th semesters at Shahid Beheshti (N=150) and Babol Dental Schools (N=125) in 2021. A structured validated questionnaire consisting of 26 questions was used to assess students' knowledge regarding the prescription, indications, and side effects of four mouthwash types: chlorhexidine, fluoride, benzydamine, and anti-plaque. The questionnaire's content validity was ensured through expert review and calculation of the content validity ratio (CVR) and content validity index (CVI). Reliability was confirmed with a test-retest method and calculation of interclass correlation coefficient (ICC). Participants' responses were scored with scores categorized as low, medium, or high knowledge. Data was analyzed using Welch’s ANOVA and independent T-tests (α= 0.05). Results: The overall mean of knowledge score was 11.22, with no significant difference between the two universities (p= 0.36).  Knowledge scores did not differ significantly between male and female students. Students' knowledge about chlorhexidine and fluoride mouthwashes was significantly higher compared to benzydamine and anti-plaque mouthwashes(p =0.033). Students' knowledge about chlorhexidine mouthwash was significantly higher in the 11^th and 12^th semesters compared to the 8^th and 9^th semesters (p=0.03), while knowledge about fluoride mouthwash showed no significant difference across semesters (p=0.16). Conclusion: The present study revealed an overall low level of knowledge regarding the proper use, indications, and side effects of mouthwashes among dental students in Tehran and Babol. The findings underscore the necessity for dental schools to enhance their educational programs by providing more comprehensive instruction on the various types of mouthwashes, their appropriate uses, potential side effects, and associated benefits.

Objective(s): Dental caries remains a prevalent chronic disease globally, with fluoride being a cornerstone in its prevention. Despite its proven efficacy, the implementation of fluoride-based strategies depends heavily on dentists' knowledge, attitudes, and practices. This study assessed the knowledge, attitudes, and practices of Iranian dentists concerning fluoride application, as well as the barriers to its use. Methods: A cross-sectional study was conducted among a convenient sample of 296 dentists. A validated questionnaire was used to collect data on dentists’ age, gender, dental specialty, working sectors and queries, such as the availability of specific guidelines for prescribing fluoride products in the workplace, self-reported practices regarding fluoride application, perceptions of barriers to fluoride use and level of agreement with statements regarding the effectiveness of fluoride in caries prevention.  Descriptive statistics and chi-square tests were employed to summarize and compare responses based on demographic and professional characteristics at p<0.05. Results: 40% of dentists had access to fluoride prescription guidelines. Younger dentists and those in both public and private sectors were more likely to report guideline availability. While 73-97% of dentists agreed with the effectiveness of fluoride in caries prevention, only 50% recognized its benefits for individuals over 12 years old. Fluoride application was more prevalent for children under 12 (30-35%), compared to adults (10%). Barriers to fluoride use included low treatment tariffs (45%), skepticism about its effectiveness (42%), and time constraints (25%). Dentists favored restorative treatments for high-risk cases, with 80% recommending fluoride varnish and gel for children but fewer for adults. Conclusion: This study highlighted gaps in knowledge and practice regarding use of fluoride among Iranian dentists, particularly for adult patients. Barriers such as low reimbursement rates and skepticism about fluoride's effectiveness need to be addressed. Enhanced training, standardized guidelines, and policy interventions are essential to improve fluoride application efforts in Iran.

Objective(s): Dental avulsion is a serious dental trauma that requires timely and appropriate management to ensure favorable outcomes. The aim of the present study was to assess the knowledge and clinical practice of general dentists regarding dental avulsion management. Methods: A cross-sectional study was conducted in 2024 among 129 general dentists in Isfahan, Iran. A structured, researcher-designed questionnaire assessed knowledge (16 items), and practice (10 items) related to dental avulsion management, focusing on critical extra-alveolar time, optimal storage media, antibiotic prophylaxis, endodontic treatment timing, and availability of educational materials, based on international guidelines. Data were analyzed using Student’s t-test and Kruskal-Wallis test to evaluate the associations between knowledge and practice scores and demographic variables (gender and years of experience). Results: The mean knowledge and practice scores were 4.97 ± 1.26 and 5.39 ±1.61, respectively, indicating moderate levels. Regarding knowledge, most dentists correctly identified the critical extra-alveolar time, while less than half recognized the optimal storage medium and appropriate timing for revascularization in open apex teeth. Approximately one-fourth acknowledged the need for antibiotic prophylaxis, and mostly underestimated the adverse effects of storing avulsed teeth in tap water. In terms of practice, about 15% had educational materials on dental avulsion in their clinics, and over 90% expressed a need for further training. No significant associations were found between knowledge scores and gender (p= 0.42), or years of experience (p= 0.43). Similarly, practice scores were not significantly associated with gender (p=0.23), or years of experience (p=0.66). Conclusion: General dentists in Isfahan demonstrated moderate knowledge and clinical practice regarding dental avulsion management, with notable gaps in key areas such as storage media, antibiotic prophylaxis, and revascularization potential. These findings highlight the need for structured continuing education programs and the dissemination of clinical guidelines to improve the management of dental avulsions.

Objective(s): Impacted third molars may lead to various pathological complications and their prophylactic extraction is controversial. The purpose of this study was to radiographically determine the relationship between common pathologies and angulation and impaction depth of impacted mandibular third molars.  Methods: In this study, 1158 panoramic radiographs with 1787 impacted lower third molars (ILTMs) were analyzed. The following pathologies were evaluated: caries in mandibular second molars, caries in ILTMs, radiolucency on distal surface of ILTMs, and bone resorption on distal surface of mandibular second molars. Data were analyzed using the chi-square test at p<0.05. Results: 58.5% of ILTMs were associated with at least one pathology. Caries of ILTMs were the most common finding  (31.1%), followed by caries (21.2%) and bone loss  (17.7%) of second molars, and distal radiolucency of ILTMs (4.3%). Caries in second and third molars and bone loss of second molars were significantly more common in mesioangular ILTMs (p<0.05). Radiolucency on distal surface of ILTMs was significantly more common in vertical ILTMs. Considering the ILTMs’ impaction depth, class A molars had more pathologies than class B or class C (p<0.05). Conclusion: Most pathologic conditions were seen in mesioangular ILTMs, especially in Class A cases. Therefore, the angulation and depth of impaction of ILTMs should be taken into account when determining whether prophylactic extraction is necessary.

Objective(s): Odontogenic Keratocyst (OKC) and Dentigerous Cyst (DC) are two common developmental odontogenic cysts affecting jaws. The role of cyclooxygenase-2 (COX2), SRY-related HMG-box gene 2 (SOX2), and Nestin in the invasion and progression of cysts and tumors has been studied. This study aimed to compare the expression of COX2, SOX2, and Nestin markers in DC and OKC. Methods: In this descriptive-analytical study, samples, including 80 paraffin blocks (32 DC, 32 OKC, and 16 cases of Dental follicle (DF)), were selected, and Immunohistochemical (IHC) staining using the antibodies for COX2, SOX2, and Nestin markers was performed using the envisioned method. Data was analyzed using the Kruskal-Wallis test at p<0.05. Results: The highest mean percentage of COX2, SOX2, and Nestin expression was observed in the DC, OKC, and DF, respectively. The only significant difference in COX2 expression was observed between the DF and DC (P = 0.001). The differences in SOX2 expression among the DC, OKC, and DF groups were all significant (P < 0.05). The only non-significant difference in Nestin expression was between the DF and DC (P = 0.157). Conclusion: COX2, SOX2, and Nestin can assist in diagnosing different inflammed types of DC and OKC. COX2 may be effective in explaining OKC's aggressive behavior. The expression of COX2 and SOX2 in DC may indicate the potential for tumoral behavior, while in OKC, it might suggest an increased epithelial proliferation rate. The findings related to Nestin expression in OKC suggest that the connective tissue of the cyst wall does not contribute to tumoral behavior and is not associated with odontogenic ectomesenchyme. Assessing molecular marker expression in IHC evaluation can help identify lesion aggressiveness and guide treatment plans to reduce future complications.

Objective(s): This study aimed to evaluate the effectiveness of the International Caries Detection and Assessment System (ICDAS) practical training in dental education, focusing on its impact on the accuracy of caries detection among dental students. Methods: In this quasi-experimental study, 18 dental students were enrolled and divided into control (theoretical training) and experimental (theoretical and practical training) groups (N=9 in each group). Theoretical training covered the ICDAS system's principles, coding methods, and caries examination techniques, while practical training involved hands-on experience on diagnosing caries in four patients identified with different ICDAS codes. Participants’ diagnostic performance was subsequently assessed at the chairside of a new patient. Statistical analysis included Fisher's exact test and logistic regression at p<0.05. Results: The experimental group significantly outperformed the control group in diagnostic accuracy, particularly for ICDAS codes 0, 1, and 4 (p=0.02, p=0.02, and p=0.004, respectively). Similarly, the experimental group achieved 100% accuracy for codes 0, 1, 5, and 6, while the control group showed lower accuracy, especially for codes 0 and 1. Conclusion: The findings highlight the importance of integrating practical training with theoretical instruction. The ICDAS-based practical education is crucial for enhancing diagnostic accuracy among dental students. Incorporating such training into dental curricula could improve caries assessment, ultimately leading to better patient outcomes. Future studies should explore these findings in larger and more diverse clinical settings.

Objective(s): This research aimed to evaluate the effect of diode laser and Remin Pro (containing nano-hydroxyapatite), both individually and in combination, on the occlusion of dentinal tubules. Methods: 45 extracted human premolar teeth were sectioned to create a 3×8 mm rectangle in the outer third of the cervical coronal dentin. The samples were then divided into five groups: negative control (with a smear layer), positive control (without a smear layer), diode laser (980 nm), Remin Pro, and combination of both. Dentinal tubule occlusion was evaluated using SEM at 2000x. Statistical analysis was performed using one-wayANOVA and LSD test at p<0.05. Results: The positive control exhibited the highest average percentage of open dentin tubules at 10.33%, while the combination treatment group showed the lowest percentage at 2.02%. When comparing the treatment methods to the positive control, all three treatments demonstrated statistically significant results (P = 0.000, 0.017, and 0.000). However, no significant statistical differences were found when the three treatment groups were compared to one another (P= 0.279, 0.935, and 0.733). Conclusion: All three treatment methods—Diode laser, Remin Pro, and their combination—effectively occluded dentinal tubules; however, none demonstrated superiority over the others.

Objective(s): The purpose of teaching professional ethics in dentistry is to cultivate dentists who adhere to ethical principles in their profession. The present study aimed to evaluate moral skills among a group of dental students. Methods: A cross-sectional study was conducted on dental students in Isfahan, Iran in 2024. Applying a stratified random sampling method, 396 volunteer dental students filled in Chambers Moral Skills Inventory including four domains of sensitivity, reasoning, integrity and moral courage. Independent t-tests and one-way analysis of variance (ANOVA) served for statistical analysis (p<0.05). Data was analyzed using SPSS version 27. Results: Among the participants (response rate=97%), with mean ± standard deviation (SD) age of 23.97±3.00 years (range: 19-39), 59.1% were women. Mean ± SD score of moral skills among the students was 15.79±3.08 (range: 8-26, scaled mean: 49.34%). A significant difference revealed between the domains (p<0.05). The highest score belonged to the domain of sensitivity (4.70) and the lowest score to the domain of reasoning (2.90).  Moral skills showed no significant association with participants’ age (p=0.51) and gender (p=0.93), however, students with father's education lower than diploma showed significantly lower score of moral skills than those with higher father's education (p=0.02). In addition, moral skills among third year dental students was significantly lower than that of fourth- and fifth-year students (p=0.01). Conclusion: Moral skills among Iranian dental students was moderate. Given the importance of ethical competencies in dental profession, it is recommended to incorporate relevant topics in to curriculum. Moreover, early exposure to ethics education should be provided for students, alongside continuing professional development opportunities for graduated dentists.

Objective(s): Various treatment modalities, such as chemotherapy, radiotherapy, and surgery, are employed for managing malignant oral tumors. This study aimed to assess dentists’ knowledge and practice regarding considerations for patients undergoing radiotherapy and chemotherapy. Methods: A cross-sectional study was conducted using a valid and reliable questionnaire completed by 250 general dentists at an annual national dental congress in 2019. Besides background questions, the questionnaire included items assessing dentists’ knowledge on managing patients undergoing radiotherapy (10 questions) and chemotherapy (12 questions), and whether they admit such patients. Results: Of 250 dentists (50% male; mean age: 45.1 ± 12 years), 126 (50%) reported experience treating patients undergoing radiotherapy/chemotherapy; 68% accepted such patients, 16% did not, and 8% referred them. Knowledge about radiotherapy considerations varied, with 77% correctly identifying poor-prognosis lesions, but only 34% aware of implant placement timing post-radiotherapy. Older dentists showed lower knowledge (p<0.001), while female dentists (p=0.005) and those with relevant experience exhibited higher knowledge (p<0.001). Similar trends occurred for chemotherapy-related knowledge: older dentists had lower knowledge (p<0.001), female dentists (p=0.002), and experienced dentists had higher knowledge (p<0.001). Conclusion: These findings underscore the need for targeted educational programs to bridge knowledge gaps and ensure optimal dental care for patients undergoing radiotherapy/chemotherapy. Enhancing dental school training and continuous professional development can empower dentists to confidently treat these vulnerable patients. Addressing these gaps is crucial for improving outcomes, equitable access, and proactive management of oncology-related oral health challenges.

Objective(s): This report aimed to illustrate the advantage of a hybrid endodontic treatment protocol—integrating orthograde retreatment with subsequent microsurgery—to resolve persistent endodontic failure in permanent molar of a growing patient, thereby preventing premature extraction. Case: A 14-year-old male was referred with a chronic apical abscess and a persistent sinus tract related to the maxillary right first molar (#16). Initial management involved conventional orthograde retreatment; however, the periapical pathology failed to resolve after a three-month observation period. Consequently, endodontic microsurgery was initiated. The surgical protocol incorporated the employment of a high power dental operating microscope, ultrasonic retro-tips, and retrofilling with a bioactive ceramic (Cold Ceramic), supplemented by guided tissue regeneration (GTR). Subsequent clinical and radiographic evaluations at one, six, and 12 months confirmed complete osseous regeneration and resolution of symptoms. Conclusion: For adolescent patients where implants are contraindicated due to incomplete skeletal development, endodontic microsurgery offers a predictable strategy for retaining natural dentition.

Objective(s): Single-rooted primary molar in considered to have a genetic origin. Knowledge of the root canal morphology is essential to achieve optimal pulp treatment in primary teeth. The occurrence of single-rooted and single-canal molars in primary dentition is extremely rare. Case: This study presents unilateral mandibular primary first molars with a single pyramidal root in two sisters, discovered in pre-operative radiographs. Pulpotomy and stainless steel crown treatment was performed for one of them that had deep caries involving the pulp. The treatment was considered successful at the 6-month follow-up. Conclusion: Obtaining radiographs prior to the treatment is essential to diagnose and properly manage single rooted molars.

Background and Objectives:
Oral squamous cell carcinoma (OSCC) accounts for over 90% of oral cancers and is traditionally associated with risk factors such as tobacco, alcohol, and HPV. Chronic inflammation and mechanical irritation, including peri-implantitis, may contribute to carcinogenesis, with early malignant lesions often mimicking peri-implantitis, leading to delayed diagnosis. This case report underscores the importance of vigilant monitoring of peri-implant lesions by presenting a case of OSCC development in a non-smoker, non-alcoholic patient in the peri-implant region.

Case Presentation:

An 84-year-old man presented with a three-month history of gingival problems. His medical history included prior heart surgery and current medications of Aspirin, Losartan, and Carvedilol. He had no history of smoking or alcohol consumption. Five years earlier, a dental implant was placed in the anterior left mandible. Based on the information provided by the patient, the implant was removed three months ago due to gingival complications; however, the precise reason for this decision remains unclear, as the patient presented to us after the implant had already been removed.

Intraoral examination revealed an exophytic lesion with a granular surface and central ulceration on the left mandibular edentulous ridge, extending buccally into the vestibular depth, lingually toward the floor of the mouth, mesially to the midline, and distally to the molar region. Radiographs showed a localized radiolucent lesion with poorly defined, non-corticated borders in the left mandibular canine-premolar region. An incisional biopsy was performed due to suspicion of malignancy. Histopathological evaluation confirmed the diagnosis of OSCC.

Conclusions:

Vigilant follow-up of implant patients is crucial for identifying and managing peri-implant lesions to prevent potential malignant transformation. Further research is required to clarify the potential etiological factors underlying the relationship between dental implants and OSCC, providing valuable insights to refine clinical guidelines.

Objective(s): Spindle cell lipoma (SCL) is a rare variant of lipoma that is uncommon in oral cavity which displays as a slow-growing, painless mass. The histopathologic diagnosis is challenging especially in low-fat/fat-free subtypes, and immunohistochemical staining is of great help in differential diagnosis. The current study aimed to report a rare case of low-fat SCL. Case: A 38-year-old male with a relatively large lesion on buccal mucosa was referred. The interventions included excisional biopsy, H&E staining, and immunohistochemical examinations. H&E study showed a peripheral soft tissue tumor. The underlying connective tissue showed collections of fatty tissue intermixed with spindle cell proliferations. In IHC study, Spindle cells were stained strongly and diffusely for CD34, and no S100 staining was detected in neoplastic spindle cells. Toluidine blue staining showed mast cells that were detected throughout the connective tissue. These findings confirmed the diagnosis of low-fat SCL. Conclusion: Oral pathologists should be familiar with the clinicopathologic characteristics of this rare lesion in order to avoid misdiagnosis.

Objective(s): Numerous studies have examined the differences in quality of life (QoL) between users of conventional complete dentures (CCDs) and implant-retained overdentures (IRODs), and have shown different results.  Methods: This comprehensive review synthesized findings from 49 studies assessing oral health-related quality of life (OHRQoL) and patient satisfaction among denture and implant prosthesis users. Databases including PubMed, Science Direct, and Google Scholar were searched (2015–2025), using MeSH terms such as “quality of life,” “satisfaction”, “overdenture”, and “denture types”, with Boolean operators. Results: Many studies employed validated instruments such as the Oral Health Impact Profile (OHIP-14 and OHIP-EDENT), Visual Analog Scales, and various satisfaction questionnaires to evaluate domains including functional limitation, pain, psychological discomfort, social impact, masticatory efficiency, and aesthetics. The evidence underscored the critical role of implant-supported prostheses in enhancing functional performance, psychological well-being, and social participation, thereby improving patients’ overall QoL. Conclusion: These findings provide valuable guidance for clinicians in selecting and tailoring prosthetic solutions to meet patient-centered goals effectively.

Three-dimensional (3D) printing has revolutionized dentistry by the ability for fabrication of patient-specific restorations consistent with individual anatomical shapes. Unlike the conventional subtractive approach, 3D printing additive manufacturing creates objects layer by layer with minimum material loss, while allowing the building of complex inner architecture, which is impossible by milling.

3D printed bioactive restorative dental materials would promote biologic restorations by the controlled release of therapeutic ions. They have been shown to release calcium and phosphate ions at a concentration sufficient to remineralize the demineralized enamel and dentin¹. In addition, the use of quaternary ammonium compounds in 3D-printed items has shown considerable antimicrobial effect by preventing Streptococcus mutans biofilm formation by up to 60%, potentially decreasing secondary caries incidence².

In periodontal treatments, β-tricalcium phosphate scaffolds made by 3D printing with pore diameters of between 300 and 500 µm have demonstrated remarkable bone form ability in preclinical studies, allowing tissue integration and vascularization at rates comparative to autografts. The scaffolds are able to perform bone formation at autograft-comparable rates, with clinical findings reporting alveolar ridge preservation and histologic evidence of vascularization and tissue integration³.

3D printing is economically a material-saving method (saving by 35–45%), with no reduction in mechanical function. Dental composites based on this method meet ISO 10477 standards for permanent crowns and bridges, with flexural strength testing as support. Fatigue resistance data in the long term are not yet based on facts, and additional clinical trials must be performed⁴. Employment of artificial intelligence (AI) in 3D printing has increased accuracy to decrease marginal discrepancies by approximately 25% compared with traditional CAD/CAM systems. Although before bringing these enhancements into practice, extensive trials and standardized clinical protocols need to demonstrate the efficacy and dependability of such enhancements⁵.

Lastly, the use of 3D printing technology with antimicrobial and bioactive dental composites is potentially a paradigm-shift approach for individualized, biologically active therapies. Evidence favors both economic benefits and clinical effectiveness with additive manufacturing for periodontal treatments and restorations. Additional research needs to be done to ensure biocompatibility and long-term stability. With advancing digital dentistry and AI, there will be a requirement for systematic clinical recommendations in order to integrate them smoothly into the routine practice^{6, 7}.