Regeneration, Reconstruction & Restoration (Triple R)

Background and objectives: This study aimed to evaluate the effect of nicotine on the biological behavior of human gingival fibroblasts on titanium and zirconia surfaces.

Materials and methods: A total of 124 Polished titanium and zirconia disc-like samples, each with a diameter of 9 mm and a thickness of 2 mm, were prepared. A contact surface profilometer was used to measure surface roughness with Ra and Rz parameters. HGFs were treated with different concentrations of nicotine. Then, their adhesion, morphology, viability, and proliferation were measured using the methyl thiazolyl tetrazolium (MTT) assay and scanning electron microscopy (SEM) at 24 and 72 hours. A t-test analysis was used to compare the surface roughness of the specimens. Data were reported as mean ± SE. Graph-Pad Prism software (version 9, USA) was used for a one-way analysis of variance (ANOVA) followed by a Tukey post hoc analysis. A P-value of < 0.05 was considered significant.

Results: The proliferation and attachment of HGF cells to the titanium and zirconia surfaces were significantly reduced by increasing nicotine concentration up to the cytotoxic range (2.5 and 5 mM) or prolonging the amount of time cells are exposed to nicotine (P < 0.05). The difference between the zirconia and titanium groups was not statistically significant (P > 0.05).

Conclusion: Nicotine cytotoxicity was concentration and time-dependent. There was no significant difference between the zirconia and titanium groups. Considering the limitations of this study and the conflicting results reported by previous studies, additional research is required to determine the superiority of these two materials, particularly in patients who smoke.

Background and objectives: Despite the increasing prevalence of root caries, little is known about how dentists manage this disease. The present study was carried out with the aim of cross-cultural adaptation and validity and reliability of the questionnaire of dentists' knowledge and experience in diagnosing, recording, and managing root caries and investigating the knowledge of dentists in diagnosing and recording root caries lesions in Iran.

Materials and methods: After obtaining permission from the main designer of the questionnaire, the process of translation and re-translation of the questionnaire was done. Cronbach's alpha was used to determine the internal consistency of the questionnaire. To determine the reliability of the questionnaire, the test-retest method was used, so that 30 of the questionnaires that were completed among the target group were redistributed to the same dentists after two weeks. Data analysis was done using SPSS version 22 software and a p-value less than 0.05 was considered significant.

Results: A total of 100 dentists were included. The validity of the questionnaire was confirmed. The average correlation of questionnaire questions was calculated as 0.948 (95% CI: 0.927 – 0.969) and the reliability of the questionnaire was calculated as 0.705 based on Cronbach's alpha. The most common restorative materials included composite resin and resin-modified glass ionomer cement. The highest prevalence of follow-up time was reported as 3 and 6 months.

Conclusion: This study showed the appropriate reliability and validity of the investigated questionnaire. According to the results of the study, the benefits of proper diagnosis, recording, and management of risk factors of root caries lesions should be highlighted in dental education and professional regulations should include more standardized management of root caries.

Background and objectives: Vertical Maxillary Excess (VME) is one of the clinical scenarios resulting from excessive vertical growth of the maxilla. The degree of mandibular autorotation affects the achievement of the desired occlusion. We aimed to determine the degree of autorotation of the mandible after maxillary impaction using cephalometric analysis with ProPlan CMF software.

Materials and methods: One individual with class 1 malocclusion and one with class 1 malocclusion and VME were included. Three-dimensional models of the jaw and face were reconstructed using cone beam computed tomography (CBCT) data for cephalometric analysis. Le Fort 1 osteotomy with three levels of maxillary impaction (2, 4, and 6 millimeters) was simulated as a whole impaction in the three-dimensional model.

Results: With a 1-millimeter impaction of the entire maxilla, autorotation of the mandible was 0.45 degrees, which increased with an increase in the impaction of the maxilla. There was an association between the impaction of the maxilla and the autorotation of the mandible. The Sella-Nasion-Basion angle increased with maxillary impaction. Consequently, the autorotation of the mandible decreased the Frankfort mandibular plane angle, from 31.8 to 29 degrees. Edge-to-edge occlusion and the necessity for mandibular osteotomy were demonstrated for impaction values exceeding 2 millimeters.

Conclusion: With a 1-millimeter impaction of the maxilla, the mandible rotated by 0.45 degrees. Further large-scale studies are recommended.

Background and objectives: Creating a white spot on the enamel around orthodontic attachments is not unexpected, and nearly half of orthodontic patients experience enamel demineralization. The aim of this study was to investigate the effect of nanoparticles on microleakage between composite and enamel.

Materials and methods: Orthodontic brackets were adhered by orthodontic adhesives in three groups on 48 extracted human premolar teeth. Three groups were studied: control and adhesive containing copper oxide and zinc oxide nanoparticles. Microleakage between adhesive-bracket and adhesive-tooth in the occlusal and gingival area of the study groups was determined by dye penetration method and statistically analyzed.

Results: Among 192 samples in three groups, microleakage was observed in 28.1% of the control group, 7.8% of zinc oxide group, and 10.9% of copper oxide group. Overall, microleakage occurred more frequently at the tooth-adhesive junction than at the bracket-adhesive junction, which was the only statistically significant factor in the GEE (Generalized Estimating Equations) analysis (P = 0.002). Differences in microleakage between occlusal and gingival margins, as well as between treatment groups, were not statistically significant.

Conclusion: Microleakage was not significantly affected by copper oxide and zinc oxide nanoparticles. No significant difference in microleakage was found between occlusal and gingival margin. Significantly greater microleakage was observed at the tooth-adhesive junction than at the bracket-adhesive junction.

Background and objectives: Orthodontic treatment is a prolonged process, and the presence of orthodontic appliances, such as brackets and braces, in the mouth is visible, which may contribute to patients' decisions to postpone the start of treatment. The present study aimed to compare the age of onset of orthodontic treatment before and during the COVID-19 pandemic in Iranian patients.

Materials and methods: This study employed a retrospective cross-sectional design. The subjects included the patients registered at the orthodontics department of the university’s Dentistry Faculty Shahid Sadoughi University of Medical Sciences, School of Dentistry. These patients’ profiles were divided into two groups according to the admission date: before (T1: 20th February 2018 to 19th February 2020) and during (T2: 20th February 2020 to 20th February 2022) the coronavirus pandemic. Patient files were reviewed according to gender and age. Independent t-tests and chi-square tests were performed for data analysis.

Results: Comparing the T1 and T2 groups, the mean ages differences of women (1.78 years) (P = 0.002) and men (1.73 years) (P = 0.038) were significantly higher after the coronavirus outbreak. Also, the overall mean age of the patients receiving orthodontic treatment was considerably higher after vs. before the coronavirus pandemic than before (P < 0.001).

Conclusions: The results of the present study showed that the mean age of the patients referring to the orthodontic department after the coronavirus outbreak was 1.79 years higher compared to the patients visiting before the pandemic, and this difference was statistically significant. Likewise, the average age of women and men referred during the pandemic increased significantly. Recognition of delayed treatment initiation can inform strategies to enhance early diagnosis and optimize referral systems.

Background and objectives: Dental phobia is a widespread issue that impacts a large portion of the world's population. As a result, various solutions have been proposed, such as applying topical anesthesia before the injection. However, there are paradoxical findings in different studies regarding the significance of pain control in dentistry. This study aims to evaluate the effect of Benzocaine Gel 20% on reducing pain for inferior alveolar nerve block.

Materials and methods: In the current double-blinded clinical trial, patients were randomly divided into two groups: the study group received 20% Benzocaine Gel (Master Dent) while the control negative group received Fluoride Gel (Master Dent AFP). An inferior alveolar nerve block injection was done afterward. The level of pain was assessed using Visual Analogue Scale (VAS). Data were analyzed using SPSS version 16.

Results: 329 patients were included of which, 149 (45.3%) and 180 (54.7%) individuals were in the control negative and intervention groups, respectively. The VAS was 73.97 ± 14.01 in the control negative and 60.68 ± 19.1 in the intervention group, which was significantly different (P = 0.001).

Conclusion: This investigation suggests that topical anesthetic substance 20% Benzocaine Gel can efficiently reduce injection pain and patients can become more comfortable during the procedure.

Background and objectives: Diabetes-induced delayed wound healing compromises dental implant success by impairing junctional epithelium formation. This study evaluated the effects of various glucose concentrations on human gingival fibroblast (HGF) proliferation and attachment to titanium and zirconia surfaces.

Materials and methods: Titanium and zirconia discs (2 × 10 mm) were prepared. HGFs were cultured on the discs or empty polystyrene plates (control) at glucose concentrations of 5.5, 11, 22, and 33 mM. Cell viability/proliferation and attachment were evaluated after 24 and 72 h using MTT assay and scanning electron microscopy (SEM). Statistical analysis was performed using one-way ANOVA and post-hoc Tukey test (P < 0.05).

Results: Glucose concentration did not significantly affect cell viability/attachment within each material group. However, HGFs proliferated significantly between 24 and 72 h at 5.5 and 11 mM glucose on titanium, and at all concentrations on zirconia. Cell viability was similar between titanium and zirconia at all concentrations except 11 mM, where zirconia performed better. At 72 h, zirconia showed significantly higher cell attachment than titanium at high glucose concentrations (22 and 33 mM).

Conclusion: Glucose did not affect initial cell attachment, but prolonged incubation (72 h) reduced cell-surface affinity on both metals compared to polystyrene. Nevertheless, zirconia promoted better HGF proliferation and attachment than titanium under high glucose conditions, suggesting zirconia as a preferable abutment material for diabetic patients.

Background and objectives: Pain is a common issue following tooth extraction. Various methods, such as sutures or mucosal adhesives, alleviate post-extraction pain. This study aimed to compare the effectiveness of Ora-Aid mucosal adhesive patches and suturing in reducing postoperative pain after tooth extraction.

Materials and methods: This clinical trial involved 18 volunteer patients undergoing the extraction of their maxillary first premolar tooth. Each patient had two premolar teeth extracted during two visits, one on each side of the maxilla. Sutures and Ora-Aid were used to cover the extraction site during each visit. The severity of pain was assessed using a visual analog scale (VAS) at 5, 12, 24, and 48 hours post-extraction. Data was analyzed using One-way ANOVA and Wilcoxon rank tests with a significance level of P < 0.05.

Results: The study included 18 participants with a mean (SD) age of 18.27 (2.72) and 44.5% (8) of them were men. At the baseline measurement (5 hours post-surgery), there was no difference in pain levels between the two groups (P > 0.05). The results indicated no significant difference in pain scores between the two groups (P = 0.445). However, pain decreased over time in both groups (P < 0.001).

Conclusion: Both techniques effectively reduced post-extraction pain, and there was no significant difference between the two in terms of pain reduction. Therefore, dentists can use either sutures or Ora-Aid based on patient preference.

Background and objectives: Considering the proximity of the roots of maxillary molars to the maxillary sinus floor (MSF) and their sensitivity to odontogenic and non-odontogenic lesions, this study aimed to show the relationship between the roots of maxillary molars and the MSF using cone beam computed tomography (CBCT).

Materials and methods: This cross-sectional study included the CBCT images of 148 fully erupted maxillary molar teeth. The evaluation included the vertical relationship between the maxillary molar and the MSF, the angle of divergence between the apex of the molar roots and the thickness of the cortex of the MSF, and the distance between the apex of the molar roots and the MSF. All parameters were analyzed by sex and age. Data were analyzed using SPSS version 22. A P-value less than 0.05 was considered statistically significant.

Results: The most frequent type of vertical relationship included the lack of root contact with the sinus border and the presence of the MSF cross-section above the root apex (type I), which was significantly more common among women than men. The highest angular deviation among the three molar roots was observed in the first molar, and the angle of divergence between the buccal (B) and palatal (P) roots was greater than the angle between the B roots.

Conclusion: Based on the results of this study, the roots of the maxillary molars are far from the MSF in most cases, and the greatest divergence of the roots is related to the first molar, and this tooth should be extracted cautiously.

Background and objectives: White spot lesions (WSLs) are one of problems caused by orthodontics treatment, resulting from enamel demineralization and leading to compromised esthetics and mechanical integrity. Recently, sub-ablative erbium laser irradiation and remineralizing agents like Remin Pro toothpaste (a hydroxyapatite-based remineralizing agent) have been proposed as potential approaches to enhance enamel resistance to demineralization. This in vitro study aimed to evaluate the effect of Er,Cr:YSGG laser irradiation and Remin Pro toothpaste on the microhardness of enamel white spot lesions following orthodontic treatment.

Materials and methods: Fifty sound extracted premolars were selected, and artificial white spot lesions were created using a standardized demineralization protocol. The samples were randomly allocated into experimental groups, including Er,Cr:YSGG laser irradiation, Remin Pro application, and a combination of both interventions. Laser irradiation was performed under sub-ablative conditions using an Er,Cr:YSGG laser (wavelength: 2780 nm) with predefined parameters for power, pulse mode, energy density, and water cooling. Enamel microhardness was assessed at different depths using a Vickers microhardness tester. Data were analyzed using SPSS (version 23) via two-way ANOVA and Tukey’s tests at a 0.05 significance level.

Results: Statistically significant differences in enamel microhardness were observed among the experimental groups as well as across different enamel depths (P < 0.05), with the highest microhardness values recorded in the combined laser and Remin Pro group in 150 micrometers depth.

Conclusions: Within the limitations of this in vitro study, Er,Cr:YSGG laser irradiation, particularly when combined with Remin Pro toothpaste, may enhance the mechanical integrity of enamel white spot lesions and improve their resistance to demineralization.

Background and objectives: There is an obvious need for an effective anti-bacterial and anti-biofilm agent to serve as an alternative to the currently used synthetic anti-microbial agents. This study sought to assess the anti-bacterial and anti-biofilm effects of the methanolic extract of Zingiber officinale (Z. officinale) on Streptococcus mutans (S. mutans) clinical isolates.

Materials and methods: This in vitro study evaluated 10 clinical isolates of S. mutans obtained from dental plaque, and its standard strain. The methanolic extract of Z. officinale was obtained by the maceration technique. The anti-bacterial activity of the extract, chlorhexidine (CHX), and chloramphenicol was evaluated by the agar diffusion technique and measurement of the diameter of the growth inhibition zones, and also by determination of the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) by the broth micro-dilution technique. The anti-biofilm effect of the microorganisms was evaluated by the microtiter plate technique. Statistical comparisons were made by the Wilcoxon and Mann-Whitney tests (alpha = 0.05).

Results: The mean diameter of the created growth inhibition zone in S. mutans culture was 15 ± 1.49 mm by the Z. officinale extract, and 21.1 ± 1.59 mm by CHX and chloramphenicol, with no significant difference among them (P > 0.05). The MIC and MBC of the methanolic extract of Z. officinale were 57.6 ± 13.86 and 76.8 ± 27.7 mg/mL, respectively. The sub-MIC of Z. officinale extract decreased biofilm formation by the isolates by averagely 20%.

Conclusion: The methanolic extract of Z. officinale significantly decreased biofilm formation (as a one of the antibiotic-resistant mechanism) by S. mutans clinical isolates, which is a promising finding.

Background and objectives: To provide a comprehensive review of the multifaceted challenges, disparities, and emerging solutions in global oral health, emphasizing the critical role of innovative technologies and public health initiatives.

Materials and methods: Oral health is a critical yet often overlooked component of global health, significantly impacting systemic health and quality of life. This review examines the challenges and disparities in oral health across various regions, highlighting the global burden of oral diseases and the socioeconomic and geographic factors hindering access to dental care.

Results: The review reveals significant socioeconomic and geographic disparities in access to dental care, underscoring the importance of preventive measures and public health initiatives. Innovative solutions and emerging technologies are shown to be transforming dental care, improving outcomes and accessibility. The impact of COVID-19 on oral health services highlights the resilience and adaptability of health systems in response to unprecedented challenges.

Conclusion: The need for integrated and equitable approaches to address the global oral health crisis is emphasized, advocating for sustained investment in innovative technologies and comprehensive public health strategies. The review underscores the critical connection between oral and systemic health, particularly in low- and middle-income countries, and highlights the essential role of public health initiatives, innovative technologies, and resilient systems in achieving equitable dental care and overall health improvement.

The cemento-enamel junction (CEJ) serves as a critical anatomical landmark in both periodontal and restorative dentistry, guiding attachment level measurement, biologic width preservation, and restorative margin placement. However, accurate CEJ localization remains clinically challenging due to its anatomical variability, soft-tissue coverage, cervical wear, and technique-related limitations. Conventional clinical methods - visual inspection and tactile probing, remain essential but are limited by operator dependence and soft-tissue interference. Standardized intraoral radiographs, especially bitewings, improve reproducibility in interproximal CEJ–alveolar crest evaluation but fail to resolve buccal/lingual surfaces. This narrative review aims to summarize and critically evaluate current methods for identifying the CEJ, highlighting their diagnostic reliability, advantages, and limitations across clinical and imaging approaches.

Platelet-rich fibrin (PRF) is a second-generation platelet derivative characterized by a dense fibrin network enriched with cytokines and growth factors. Its preparation includes involves centrifugation of autologous blood without anticoagulants that form a concentrated fibrin matrix, which could be inserted directly into the site of injury or used as a membrane for specific applications. Higher concentrations of growth factors in PRF lead to faster periodontal regeneration and higher clinical attachment gain, along with new bone formation. Thus, it’s widely used in periodontal treatment. PRF has also shown promising results in implant dentistry. This review aims to summarize the current knowledge concerning the applications of PRF in periodontal treatment and implant dentistry and highlight its potential to improve clinical outcomes in these fields.

Salivary duct cyst (SDC) is a rare reactive lesion of the salivary gland ducts and is infrequently reported in minor intraoral glands, particularly the lower lip. We describe a 49-year-old man with a painless, well-circumscribed submucosal swelling of the lower lip. Clinical findings suggested mucocele or salivary gland tumor, and excisional biopsy revealed a cyst lined by thin cuboidal epithelium adjacent to salivary gland lobules, confirming SDC. The lesion was completely removed, and no recurrence has been observed. Furthermore, a review of English-language literature from PubMed, Scopus, and Web of Science shows that intraoral SDCs typically affect middle-aged adults, demonstrate slight female predominance, and present as soft, mucosa-colored swellings with variable histopathologic patterns, including occasional epithelial metaplasia. Surgical excision remains the preferred management, with recurrence considered rare, although follow-up is recommended. This case underscores the need to include SDC in the differential diagnosis of atypical lip swellings.

Schwannoma is a benign neurogenic neoplasm originating from the Schwann cells within the peripheral nervous system. Its incidence is documented at about 25-45%, yet its occurrence in the oral cavity is less than 12%. Given that neurogenic neoplasms are a well-documented but uncommon reason for hyponatremia, this is a case report of an ancient schwannoma of the palate, perforating the nasal floor, in an 80-year-old female, along with hyponatremia.

An 80-year-old female presented with painful swelling in the anterior maxilla and the nasal floor. She had a history of hyponatremia, high blood pressure, tachycardia, and hypothyroidism. Clinical examination revealed apparent swelling in the buccal vestibule and the midline of the hard palate; the lesion had perforated the palate to the nasal cavity. cone beam computed tomography revealed swelling of the soft tissue and erosion of the underlying bone. An excisional biopsy surgery was performed by laser. Microscopic examination showed spindle cell neoplasm composed of cellular areas (Antoni A), nuclear palisading (verocay bodies), and pauci-cellular microcystic areas (Antoni B). Some tumoral cells showed nuclear atypia including nuclear enlargement with hyperchromasia with irregular border. Given that, the definitive diagnosis was an ancient Schwannoma.

The present case is a unique type of schwannoma, placed in an uncommon location. It presented pain and, more importantly, perforated the hard palate to the nasal cavity.

Osteomyelitis is an inflammatory condition of bone caused by infection, rarely affecting the maxillofacial region in children, often linked to systemic predisposing factors.

This study reports a case of an 8-year-old boy presented with exposed mandibular bone following self-extraction of a deciduous tooth. Radiographic evaluations revealed an ill-defined radiolucent lesion in the left mandible. Laboratory tests showed elevated Erythrocyte Sedimentation Rate (ESR) and Positive C-reactive Protein (CRP) levels. Histopathologic examination confirmed osteomyelitis, characterized by nonvital lamellar bone, bacterial colonization, and chronic inflammatory cells infiltration, indicating the diagnosis of chronic osteomyelitis.

This case highlights the need to consider osteomyelitis in non-healing extraction sockets, even in patients without systemic disease and within an age group where the condition is uncommon.

Maxillary canines are the second most commonly impacted teeth, with palatal impactions predominating. Forced eruption supported by temporary anchorage devices (TADs) can minimize adverse effects on adjacent teeth and shorten the preparatory phase. A 17-year-old male presented with maxillary left canine impaction (#23). Extraoral examination showed mild facial asymmetry; intraorally, there was absence of #23, anterior crowding, and a Class II subdivision molar relationship on the right. CBCT revealed a horizontally impacted palatal canine in close proximity to the left incisors. Cephalometrics indicated a Class I skeletal pattern with hypodivergent growth. A canine-first approach was used. Skeletal anchorage was obtained with a 1.6 × 8 mm palatal miniscrew between the left second premolar and first molar. The canine was surgically exposed, a palatal button bonded, and immediate traction applied with elastic thread, followed by a ballista spring. Fixed appliances (0.022-in slot) were used with sequential NiTi and stainless-steel archwires. To avoid lateral incisor root contact, initial retraction was directed posteriorly from the TAD before buccal movement. Space creation with open-coil springs and later interarch Class II elastics on the right were employed. Torque control of the canine was finalized with rectangular archwires. Total active treatment time was 34 months; retention included a braided fixed lingual retainer and a removeable retainer. Posttreatment records showed Class I canine and molar relationships bilaterally, normal overjet/overbite (2 mm/2 mm), improved midline coincidence, appropriate root parallelism, and no radiographic evidence of root or bone loss. Facial profile was harmonious on lateral cephalometry. CBCT-guided, TAD-assisted forced eruption using a canine-first protocol enabled safe, controlled disimpaction of a palatally impacted canine, preserving anchorage and protecting adjacent roots while achieving stable functional and esthetic results.

Oral verruciform xanthoma is an uncommon papillary lesion that is often not taken into consoderation in differential diagnosis of oral papillary lesions. The current case is a solitary papillary lesion on right hard palate of a 33-year-old male with no histroy of swelling or pain. Clinical, histopathologic and immunohistochemical findings of the case is presented and briefly discussed. The aim of the current case report is to attract the clinicians' attention to uncommon lesions such as verruciform xanthoma.

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