Regeneration, Reconstruction & Restoration (Triple R)

Background and objectives: The use of antibacterial substances is necessary to reduce pathogens without damaging the normal flora of the oral cavity. Therefore, this study aimed to investigate the antibacterial effect of bitter and sweet almond extracts on Streptococcus mutans, Lactobacillus acidophilus, Enterococcus faecalis, Streptococcus salivarius and Streptococcus sobrinus.

Materials and methods: In this experimental study, laboratory samples were analyzed in three groups as follows: bitter almond extract (Prunus Amygdalus amarus) group, sweet almond extract (Prunus Amygdalus dulcis) group and 0.2% chlorhexidine. To determine the antibacterial effects of the extracts on the aforementioned bacteria, the disk agar diffusion method was performed according to the CLSI manufacturers. Data were collected and analyzed using SPSS26 software as well as Kruskal-Wallis and Mann-Whitney tests.

Results: Findings suggested that Chlorhexidine had the greatest antibacterial effect against the tested bacteria. Bitter and sweet almond extract had no effect on E. faecalis and despite the effect on other bacteria; this effect was not statistically significant
(P > 0.05). A 12.33 mm and 10.6 mm inhibition zone diameter of the bitter and sweet almond extracts was observed against S. sobrinus, respectively.

Conclusion: The antibacterial effect of chlorhexidine on the tested oral bacteria was much higher than the bitter and sweet almond extracts. Also, the bitter and sweet almond extracts had no effect on E. faecalis. However, the bitter almond was more effective than the sweet almond.

Background and objectives: An essential factor in building a harmonious facial profile from an aesthetic view is the change in the gonial angle, which occurs in some orthognathic surgery cases. Occlusal plane alteration is an alternative surgical technique for optimal aesthetic results and function. This study aimed to determine the cephalometric relationship between changes in the occlusal plane and gonial angle.

Materials and methods: In the present study, 76 patients who underwent bimaxillary orthognathic surgery were divided into class II and III groups. All patients had lateral cephalometric radiographs before and for a short time (maximum three weeks) after surgery. Then, cephalometric analysis of these radiographs was conducted by an orthodontist using Hexagon Imaging software, and changes in cephalometric angles were compared using two series of radiographs. Variables before and after surgery were assessed using paired t-tests, and differences in their changes were assessed using a regression test. The Pearson correlation test assessed the association of different values of the occlusal plane slope before surgery with changes in different variables.

Results: Changes in the occlusal plane were not significantly associated with changes in the gonial angle. However, changes were significant regarding the relationship between the articular and gonial angles, especially in class II patients. Gonial angle also increased significantly in class II patients and slightly decreased in class III patients. In patients whose occlusal plane rotated clockwise (mean 2.6 degrees) and those whose occlusal plane rotated counter-clockwise (mean 4.06 degrees), a strong association was observed between changes in gonial angle and articular angle.

Conclusion: There is no association between cephalometric changes in occlusal plane angle and changes in gonial angle in class II and III patients undergoing bimaxillary surgeries.

Background and objectives: Establishing a strong and durable bond between cements and root canal dentin has been widely studied. Since the effectiveness of proanthocyanidin (PA) as a collagen cross-linker has been proven, the strength and durability of the bond between fiber posts and root canal dentin are expected to increase following the application of PA. Therefore, the present study aimed to assess the effect of PA pre-treatment on the bonding durability of fiber posts with three resin cements.

Materials and methods: Ninety human single-rooted teeth with similar anatomical root shape and length were collected. After decoronation and root canal therapy, the teeth were divided into nine groups: etch and rinse (ER), self-etch (SE), self-adhesive (SA), PA pre-treatment and etch and rinse (PAER), PA pre-treatment and self-etch (PASE), PA pre-treatment and self-adhesive (PASA), chlorhexidine (CHX) pre-treatment and etch and rinse (CHXER), CHX pre-treatment and self-etch (CHXSE), and  [ CHX pre-treatment and self-adhesive (CHXSA). After microslicing the roots, push-out tests were performed immediately for half the specimens and after three months of water storage and thermocycling for the other half. Data were analyzed using two-way ANOVA and Tukey’s test with α=0.05.

Results: Resin cement type (P=0.001), dentin pre-treatment method (P=0.001), water storage and thermocycling (P=0.001), and the root region (P=0.001) had significant effects on bond strength.

Conclusion: SA resin cement had the lowest immediate and long-term bond strength in comparison with the other two cements. For ER and SE resin cements, no pre-treatment led to higher immediate and long-term bond strength. For SE and SA resin cements, PA pre-treatment inhibited the loss of bond strength in the long-term. The bond strength in the coronal region was higher than that in other regions.

Background and objectives: Correct application of the Finite Element Method (FEM) can simulate tooth displacement and stress distribution in the periodontium under external forces and offer the correct prediction and appropriate therapeutical choices. The present study analyzed the alveolar bone's mechanical behavior under typical intrusion or oblique forces for several levels of reduced periodontium using a dynamic linear/ nonlinear simulation.

Materials and methods: This study's modeling, meshing, simulation, and finite element analysis were carried out using SolidWorks software (2021, SP2, Dassault Systèmes). The mandibular and maxillary canines were modeled using cone beam computed tomography images. Teeth, lamina dura and cortical and cancellous bones were considered linear isotropic material, whereas the periodontal membrane was considered a hyper- elastic first-order Ogden material to account for its flexibility. Crown- to- root ratio (C/R) of 0.8, 1.25, 2 and 3.5 was simulated. All simulations were dynamic nonlinear/ linear to account for the natural displacements in the periodontium under occlusal forces. The teeth were submitted to intrusion or oblique (15 and 45 degrees) 100 Newton to simulate typical occlusal forces.

Results: The maximum von Mises stress and maximum equivalent strain for all models increase with bone loss. Furthermore, the rate at which these factors increase from each bone loss step to the following increases noticeably after 6 mm of bone loss. The amount and rate of increase in the maximum stress and stress experienced by alveolar bone are higher for forces with higher degrees of deviation from the tooth axis. The maximum stress and strain for the intrusion, 15-degree and 45-degree models were 137Mpa/ 0.006, 268Mpa/ 0.013 and 800Mpa/ 0.040, respectively (All at C/R = 3.5).

Conclusion: Reduction of alveolar bone level (increased crown- to- root ratio) leads to higher levels of stress and strain, which show a steep rise at the 6 mm of bone loss. This observation leads our attention toward tooth-specific occlusal consideration in patients with reduced periodontium.

Background and objectives: The principal problem in the treating heart damages is the restricted ability of the heart to restore. Injectable hydrogels offer considerable potential for repairing cardiac tissue. According to the features of chitosan and polyvinyl alcohol (PVA) in the cardiac repair, preparing a hydrogel that imitates the extracellular matrix (ECM) of the heart and is a new treatment for heart patients, especially heart infarction, the purpose of the current study is to design, fabrication and in-vitro specification of injectable chitosan/ PVA scaffold for heart tissue engineering.

Materials and methods: The prepared hydrogel consisted of 2% natural chitosan and 5% synthetic PVA. The characteristics of the prepared hydrogel were assessed by experiments of gelation time, pH determination, microbial culture, biodegradability, swelling ratio, toxicity and microscopic evaluation of three-dimensional culture.

Results: The evaluation of chitosan/PVA hydrogel experiments displayed that the gelation time was 7.66 ± 1.69 minutes and the pH measurement was 7.03 ± 0.12. The bacteria did not grow in the microbial culture. The degradability of hydrogel occurred after one week of immersion in PBS, which indicated its biocompatibility. The highest swelling was observed at 3 hours after immersion in PBS and then, the hydrogel started to lose water and shrank. The hydrogel was not toxic to adipose- derived mesenchymal stem cells (ADMSCs) and created a suitable three-dimensional structure for the growth and proliferation of ADMSCs and the cells maintained their attached and morphology.

Conclusion: We demonstrated the development of biocompatible and injectable chitosan/ PVA hydrogel scaffold with high cellular compatibility, which along with other evaluations can use as a biomaterial in cardiac tissue engineering.

Background and objectives: Age determination has various applications, including providing information for archaeology and identifying individuals in forensic medicine. Various methods have been recommended to date for determining age. One of these methods was presented in 2006 by Cameriere et al., which was based on the assessment of the root of only one tooth (the third molar). The aim of this study is to assess the accuracy of the third molar index in determining the legal age of the Iranian population aged 15-24 years old.

Materials and methods: In this cross- sectional study, 300 panoramic radiographs (184 Females and 116 Males) were used. Patients were aged 15-24 years old. the legal age was determined based on the Cameriere’s method and compared with the actual age of the individuals. Data were analyzed using SPSS Ver. 20 with descriptive statistics and the ROC curve. The significance level was set at P-value < 0.05.

Results: After performing statistical analysis, the results were as follows: Sensitivity was 77% (95%, CI: 0.72 - 0.83), specificity was 93% (95%, CI: 0.87 - 0.99), the positive predictive value was 97% (95%, CI: 0.72 - 0.81), and the negative predictive value was 56% (95%, CI: 0.47 - 0.65).

Conclusion: This study found that Cameriere's third molar index is 91% accurate in distinguishing individuals above and below 18 years old. However, due to limitations like specific age ranges and non-randomized sampling, further research with larger, more diverse samples is needed. If validated, the index could be useful for forensic age estimation in the Iranian population.

Background and objectives: This study assessed the effect of thickness of high-translucent (HT) and super-translucent (ST) monolithic zirconia on its color, translucency, and marginal and internal adaptation.

Materials and methods: Monolithic zirconia restorations were fabricated from HT and ST zirconia blanks (n=30) with 0.5-, 1- and 1.5-mm thicknesses (n=10). The color and translucency parameter (TP) was measured by a spectrophotometer, and marginal gap (MG), internal gap (IG), and occlusal gap (OG) were measured by the replica technique.

Results: Zirconia type had no significant effect on TP (P=0.362) but the effect of thickness was significant (P<0.001); 1.5-mm thickness yielded the lowest and 0.5-mm thickness yielded the highest TP. Zirconia type (P<0.001) and thickness (P=0.001) had significant effects on color difference (ΔE); ST yielded significantly higher ΔE, and 0.5-mm thickness resulted in significantly lower ΔE than 1-mm (P=0.047) and 1.5-mm (P<0.001). The MG of both HT and ST increased with thickness (P<0.05). The IG of 0.5 mm-thick restorations was significantly higher than 1 mm (P=0.005) and 1.5 mm (P=0.003). In ST restorations, the difference in IG was not significant among different thicknesses (P>0.05). OG was the highest in 0.5 mm thickness. In ST restorations, minimum OG was found in 1 mm thickness. Zirconia type had no significant effect on adaptation (P>0.05).

Conclusion:  Zirconia type had no significant effect on TP or adaptation. Increasing the thickness decreased TP. ΔE was lower in lower thicknesses, and ST zirconia yielded higher ΔE. Thickness had a direct correlation with MG and an inverse correlation with IG and OG.

Background and objectives: Choosing the wrong shade is a common reason for the failure of prosthetic treatments. Shade selection ability varies from person to person and in different situations. The current study aimed to evaluate tooth shade selection ability and repeatability among dental students in the School of Dentistry, Zahedan University of Medical Sciences and to assess the effect of gender, academic year, and wearing eyeglasses, or contact lenses on shade perception.

Materials and methods: In this cross-sectional study, each student selected the shades of mid-cervical and mid-incisal parts of the maxillary canine tooth of a patient using the Vita Classical shade guide (Vita zahnfabrikBad, Säckingen, Germany) and their ability was evaluated as poor, moderate, or good. After one month, the shade selection was repeated for the same patients to examine shade selection repeatability. The Chi-square and Fisher’s exact tests were applied to analyze the data (P < 0.05).

Results: The final sample consisted of 60 students: 28 sixth-year students (12 males, 16 females) and 32 fifth-year students (12 males, 20 females). It was observed that 75% and 25% of the students had poor and moderate shade selection abilities, respectively. None of the participants showed good ability. Intra-rater repeatability was 10%. There was no statistically significant association between shade-selection ability with any of the variables of shade-selection repeatability (P = 0.16), gender (P = 0.22), academic year (P = 0.07), and the use of eyeglasses (P = 0.48) or contact lenses
(P = 1.00).

Conclusion: Considering the poor shade selection ability and repeatability among dental students in Zahedan City, actions should be taken to develop educational interventions concerning shade selection. Gender, academic year, and wearing eyeglasses or contact lenses did not have a significant effect on shade perception.

Background and objectives: Internal fixation is the preferred method for craniomaxillofacial, orthognathic and reconstructive surgeries. However, it can lead to complications, which may vary depending on the type of surgery and patient demographics. Common complications include screw loosening, plate breakage and infections. For instance, infections may be more prevalent in patients with pre-existing conditions or those undergoing complex reconstructive procedures, while plate breakage might be more frequent in high-impact trauma cases. This study aimed to investigate the causes and factors related to plate removal surgery in Iran.

Materials and methods: This retrospective study investigated the prevalence and causes of titanium plate removal in patients who underwent plate removal surgery between 2019 and 2023 in two hospitals in Tehran, Iran. Data were collected from registered electronic files, with a focus on the date and cause of plate insertion and removal, the time interval between these events, and the demographic profiles of the patients, and the data were analyzed using descriptive statistics.

Results: A total of 1,776 patients were included in the study, with a plate removal rate of 4.3%. The participants who underwent plate removal were mostly males (n= 44; 57.9%) with a mean age of 32.7 ± 16.6 years. The patients were categorized into five groups on the basis of the reason for plate placement: trauma, pathology, orthosurgery, esthetics and cleft. The median duration of plate placement was 14 months, with infection being the primary cause of early removal. Most of the removed plates were located in the mandible, with the highest concentrations in the angle and body areas.

Conclusion: This study revealed a low frequency of plate removal, primarily due to infections, with variations observed by age and sex. It is recommended that future large- scale, multicenter studies with extended follow-up periods be conducted to gain a deeper understanding of the epidemiology, risk factors, causes, and complications associated with plate removal.

Background and objectives: Tooth extraction is often associated with pain and discomfort for patients. There are still controversies over the proper painkiller with minimum side effects to be prescribed after extractions. Therefore, the current study aims to compare the pain-relieving effect of Novafen versus Ibuprofen after maxillary and mandibular molar extractions.

Materials and methods: The present cohort study consisted of 80 healthy individuals who were candidates for extraction of their molar teeth under local anesthesia. Patients were randomly divided into two groups (N = 40) and were instructed to use Novafen or Ibuprofen, respectively, every 6 hours post-extraction. Pain assessment was conducted using Visual Analogue Scale (VAS). Data analysis was performed using SPSS v25. The Chi square test was performed for qualitative and t-tests for quantitative variables. Pain relief times were compared using Kaplan-Meier curves and Cox regression, with hazard ratios assessing differences between the two drugs.

Results: The findings revealed that both medications affected similarly up to 12 hours post-treatment; however, Novafen exhibited a shorter time to pain relief than Ibuprofen after 12 hours. Thus, Novafen demonstrated a significantly faster time to pain relief than Ibuprofen (P < 0.005). Moreover, the hazard ratio for the analgesic effect of Novafen relative to Ibuprofen was 2.55, indicating that Novafen has a shorter time to pain relief than Ibuprofen (P < 0.002).

Conclusion: Both Novafen and Ibuprofen are effective in reducing pain after molar extractions; however, Novafen can be a more reliable choice in reducing pain and discomfort.

Background and objectives: Due to the lack of definitive conclusions about the effects of passive smoking on periodontal health especially in adults and the lack of information on the relationship between salivary calcium levels and periodontitis, this study aimed to compare salivary calcium levels and periodontal status of passive smoking and non-smoking adults.

Materials and methods: This cross-sectional study was conducted on 60 adult females in two groups of passive smokers and non-smokers (n=30), who were selected using consecutive sampling. The salivary calcium levels were measured using an enzymatic colorimetric method with a kit, and their periodontal health was evaluated by measuring clinical attachment loss (CAL), bleeding index (BI), and probing depth (PPD). The values were then compared between the two groups. Data were analyzed using t-tests, Mann-Whitney tests, Pearson and Spearman’s correlation coefficients (α=0.05).

Results: The mean CAL was significantly higher in passive smokers than in non-smokers (P=0.013). The mean values of BI (P=0.446), PPD (P=0.066), and salivary calcium levels (P=0.248) were not significantly different between the two groups, although slightly higher values were recorded in the passive group. In passive smokers, the mean PPD had a significant correlation with the salivary calcium levels (P=0.037). In non-smokers, CAL and salivary calcium levels were significantly correlated (P=0.010).

Conclusion:  Passive smokers had significantly greater CAL than non-smokers. Additionally, higher salivary calcium levels were significantly correlated with higher mean PPD in passive smokers and CAL in non-smokers, indicating a possible association between elevated salivary calcium levels and periodontal problems, regardless of smoking status.

Background and objectives: This article delve into the valuable insights provided by molecular markers, particularly Matrix Metalloproteinase 9 (MMP-9), in the context of pulpal diagnosis. It emphasizes the challenges associated with current diagnostic tools and advocates for enhanced methods to ensure a reliable diagnosis. Elevated MMP-9 levels emerge as potential biomarkers not only for pulpal diseases but also for periodontal and cardiovascular conditions. The exploration extends to molecular alterations and diagnostic biomarkers in gingival crevicular fluid, shedding light on promising avenues for dental diagnosis and customized treatment approaches.

Materials and methods: Gingival crevicular fluid (GCF) samples were collected from 56 eligible patients using medium-sized paper points. A second set of GCF samples was collected two weeks post- root canal treatment. Normal samples were obtained from patients referred for routine dental check-ups. GCF samples were transferred to sampling tubes with Tris HCL pH = 7.5 buffer. MMP-9 levels were measured using ELISA.

Results: Statistical analysis revealed a significant decrease in MMP-9 levels in GCF after root canal treatment for both symptomatic and asymptomatic irreversible pulpitis (P-value < 0.05). The study identifies an increase in MMP-9 during pulp inflammation. Subsequently, MMP-9 levels decrease in the gingival crevicular fluid after root canal treatment, indicating the resolution of inflammation.

Conclusion: Precision in evaluating and measuring enzymes associated with pulp tissue destruction in the local gingival crevicular fluid is achievable through a precise method. The examination of MMP-9 in gingival crevicular fluid can serve as a valuable tool for monitoring inflammatory activity and assessing the success of treating teeth with symptomatic and asymptomatic irreversible pulpitis.

Background and objectives: The most important anatomical areas to take into account during implant insertion are the submandibular gland cavity, the posterior part of the mandible, and the inferior alveolar nerve. Therefore, this study aims to assess the location of the submandibular gland fossa and its variations using CBCT.

Materials and methods: In this cross-sectional investigation, CBCT images of the mandible of patients who visited a private radiology center in Babol (Mazandaran, Iran) between 2019 and 2021 were included. The submandibular salivary gland fossa was evaluated based on age, sex, side of the mandible, fossa depth and angle, as well as connection with the mental foramen and mandibular canal. Data were analyzed using SPSS V.24.

Results: The study population comprised 59 men (47.2%) and 66 (52.8%) women, ranging from 16 to 70 years old. The mean depth of the fossa on the right side (1.79 ± 0.48 mm) was statistically greater than the left side (1.66 ± 0.46 mm). Regarding the angle of the fossa and the distance to the mental foramen, there was no discernible difference between the left and right sides. Men had considerably deeper average fossa depths on both sides (P<0.05). Moreover, the fossa depth on the right side was significantly lower in patients less than 36 years old (P=0.005).

Conclusion: According to the current findings, the average depth of the fossa is greater on the right side than on the left side. The deepest part of the fossa is located next to the mandibular canal. Therefore, it is crucial to have a thorough understanding of the characteristics of the submandibular gland fossa to avoid perforating the lingual alveolar plate during implant insertion.

Keywords: Cone Beam Computed Tomography, CBCT, Dental implant, Submandibular gland fossa.

Background and objectives: The current study aimed to evaluate and compare the validity and precision of the information provided by three online artificial intelligence (AI) platforms, including GPT-3.5 (Open AI), Claude-Instant (Anthropic), and Copilot (Microsoft), in the context of laboratory protocols in the field of tissue engineering.

Materials and methods:  Three specialists in the field of tissue engineering research and molecular and cellular laboratory methods created a survey with 20 open-ended questions. The questions included a variety of subjects regarding cell culture processes and cell analysis techniques. The chatbots' responses to the open-ended inquiries were assessed according to the modified global quality scale. A P-value less than 0.05 was considered statistically significant.

Results: GPT-3.5, with a median score of 4 out of 5, performed significantly better than Claude-Instant and Copilot. GPT-3.5 showed superior performance compared to Claude-Instant (P < 0.001) and Copilot (P = 0.007). Both Claude-Instant and Copilot chatbots received a median score of 3 out of 5 in total.

Conclusion: In conclusion, AI language models provided satisfactory responses for laboratory procedures in the field of tissue engineering. Specifically, GPT-3.5 outperformed both Claude-Instant and Microsoft Copilot chatbots. Nevertheless, the information offered by all three chatbots was insufficient in terms of the crucial details required for the design and execution of an in vitro analysis.

Background and objectives: This study aimed to assess the knowledge level of Yazd dental students about bisphosphonate-related osteonecrosis of the jaw (MRONJ).

Materials and methods: This cross-sectional study was conducted on 113 fourth- to sixth-year dental students of School of Dentistry, Yazd Shahid Sadoughi University of Medical Sciences. A questionnaire was used to collect information regarding age, gender, academic year, grade point average (GPA), and history of encountering a case of MRONJ. The questionnaire had 13 multiple-choice questions regarding the knowledge level of students about the definition, classification, frequency of use, side effects, risk factors, and indications of bisphosphonates and treatment of MRONJ. Data were analyzed by t-test and Pearson’s correlation test (alpha = 0.05).

Results: A total of 69 (61.1%) female and 44 (38.9%) male dental students participated in this study. The mean knowledge score of students about MRONJ was 14.42 ± 3.84 out of 17. No significant difference was found in the mean knowledge score of male and female students (P = 0.518). Knowledge score of students had significant inverse correlations with their age (r = -0.306, P = 0.001) and academic year (r = -0.184, P = 0.050) and a significant direct correlation with their GPA (r = 0.330, P = 0.000).

Conclusion: The present results revealed good knowledge level of Iranian dental students regarding MRONJ. Knowledge level of students had significant inverse correlations with their age and academic year, and a significant direct correlation with their GPA.

Background and objectives:  Despite developments in the field of patient rights laws in Iran, there is still no single policy in the field of informed consent, which may be interpreted as the formality of obtaining consent without considering its principles. No domestic studies were found on this topic, especially in the dental field. Therefore, this study was conducted to evaluate the Knowledge, Attitudes, and Practices (KAPs) of dentists regarding informed consent in Yazd.

Materials and methods: In this cross‑sectional study of 146 dentists, a pretested, researcher-made self-administered questionnaire was used. Mann‒Whitney and Kruskal‒Wallis tests were performed for analysis.

Results: Knowledge and practice levels were considered acceptable, but attitudes were not. There was no significant difference in knowledge or attitude scores based on age, gender or years of clinical experience. Practice scores did not differ based on sex, but there was a significant difference according to age and years of clinical experience. There was a moderate direct correlation between the practice score and both the attitude and knowledge scores.

Conclusion: The KAP of Yazd dentists, especially regarding the principles of obtaining informed consent, needs improvement.

Background and objectives: Oral health impact profile index (OHIP-14) is considered one of the most famous and reliable known strategies for identifying and evaluating various aspects of the quality of life associated with oral health. In spite of the developmental studies in this field, very few studies have implant-dependent prostheses recipients are a community of their own. In the present study, which is conducted in Iran for the first time, we intend to study the effect of using implant-dependent prostheses on the quality of life during 6 and 12 weeks.

Materials and methods: The research was a descriptive cross-sectional study in which 126 patients referred to a number of dental clinics. The Implant-based Treatment Plan was considered for their prosthetic treatments. They are interviewed before the start of the treatment process and respond to questions from the OHIP-14 questionnaire. In addition, after the relative improvement of the site of implant surgery, the questionnaire was reinstated by the patients before the process of prosthetic rehabilitation was started. In the next stage, after receiving the prosthesis, after 6 weeks and then 12 weeks, the questionnaire was completed again.

Results: The mean score of the questionnaire before the treatment was 39.17, after the surgical stage, 41.47, six weeks after the delivery of the prosthesis 30.15 and 12 weeks after the delivery of the final prosthesis was 27.87. The average of the total scores varied in different stages, increasing between the first and second stages, and then decreasing further, and the difference between the mean of the total scores in these sections was significant (P < 0.0001). In other words, the quality of life associated with oral health in postoperative patients decreases somewhat and will increase significantly in post-delivery delivery of the final prosthesis.

Conclusion: In conclusion, an increase in quality of life was observed after the completion of prosthetic reconstruction in all domains of OHIP-14. The patients with prosthesis receiving more than three units generally have better results in physical scales.

Background and objectives:  This study aimed to investigate the in vitro effects of two Listerine mouthwashes—one alcohol-free and the other containing alcohol—on the shear bond strength of orthodontic brackets.

Materials and methods: This experimental study was accomplished on 45 healthy human premolars that were extracted for orthodontic treatment. The teeth after mounting in acrylic blocks were bonded with metal orthodontic brackets (MBT/0.22) by composite and randomly divided into three groups: (1) alcohol-containing Listerine mouthwash (ACLM), (2) alcohol-free Listerine mouthwash (AFLM), (3) artificial saliva (control). 15 samples were placed in each group. After keeping teeth in the solutions, the shear bond strength of orthodontic brackets was measured by the universal testing machine at a speed of 1 mm/min, and the information was compared using one-way ANOVA analysis.

Results: In general, the average shear bond strength of 45 premolars was evaluated as 20.92±6.8 MPa. Shear bond strength was reported as 18.32±7.33 MPa in the first group (Listerine containing alcohol), 22.33±7.27 MPa in the second group (Listerine without alcohol), and 22.22±5.27 MPa in the third group (control group). The highest and lowest mean shear bond strength of the bracket to the tooth surface were shown in the alcohol-free Listerine and the alcohol-containing Listerine groups, respectively. The results of one-way ANOVA showed no statistically significant difference in terms of shear bond strength among the three groups (P-value˃0.05).

Conclusion: Since both alcohol-containing and alcohol-free Listerine mouthwashes are effective in reducing viral and oral microbial loads, the lack of significant impact on bracket bond strength supports the recommendation of these mouthwashes in orthodontic practice.

Background and objectives:  The second common source of orofacial pain is temporomandibular disorder (TMD). Occlusal splints are prevalently applied to manage symptomatic TMD.  This study aimed to discuss the types, characteristics, fabrication, and application of occlusal splints.

Materials and methods: A structured search was carried out, including PubMed and Scopus databases with additional integration from external sources to March 2020. To meet the inclusion criteria, studies published in English involving randomized clinical trials, review articles, and experimental studies, starting from the 215 identified records, 75 items were finally included for the review.

Results: The critical step in treatment of patient with pain, malfunction, and discomfort is to determine the primary etiology. The two most commonly used splints are stabilization and anterior positioning appliances. Other types include anterior or posterior bite plane, pivoting appliance, and soft or resilient appliance.

Conclusion:  There are various splints in the literature; a dentist must select the appropriate one with predictive success based on the specific diagnosed TMD type.

Background and objectives: Maxillary advancement (MA) is a common surgical procedure for correcting facial-skeletal discrepancies in patients with cleft lip and palate. Despite its prevalence, the impact of MA on velopharyngeal insufficiency (VPI) remains a subject of debate. This systematic review and meta-analysis aims to evaluate the effect of MA on VPI in cleft palate patients.

Materials and methods: Adhering to PRISMA 2020 guidelines this review included randomized controlled trials and observational studies assessing velopharyngeal function pre- and post-MA in cleft palate patients. Exclusion criteria encompassed studies on non- cleft palate patients and those lacking VPI assessments. Searches were conducted in databases like PubMed, MEDLINE, Embase, Scopus, and Cochrane Library, up to September 2023. Studies were selected and data was extracted by two independent reviewers, with disagreements resolved through consultation. The risk of bias was assessed using Cochrane's risk of bias tool. A meta-analysis was conducted using inverse variance meta-analysis with random effects for categorical data.

Results: Eleven studies involving 524 patients were included. Studies varied in design, patient demographics, and type of cleft. MA procedures primarily involved LeFort I osteotomy. Speech and VPI assessments employed various methods. Analysis revealed a shift from normal to hypernasal speech postoperatively, with a general trend towards aggravated VPI, especially in cases of MA more than 6mm. The meta-regression (coefficient of -20.35 with a standard error of 8.63, a T-value of 2.36, and a P-value of 0.046) showed a significant relationship between the extent of MA and VPI outcomes. High heterogeneity was observed across studies.

Conclusion: Maxillary advancement, especially when less than 6 mm, can negatively impact velopharyngeal insufficiency in patients with cleft palate. Successful outcomes require comprehensive preoperative assessment, precise surgical planning, collaborative care, and vigilant postoperative monitoring to minimize the risk of VPI and improve patient outcomes.

Various surgical techniques have been developed to reconstruct keratinized tissue (KT) around dental implants, including the use of acellular dermal matrix (ADM). However, ADM grafting is commonly performed with a partial-thickness flap, which can be technique-sensitive and may lead to flap thinning or perforation.

In this case, a 54-year-old male presented with discomfort and hygiene issues around mandibular implants placed 10 months prior. Clinical examination revealed a thin gingival biotype, inadequate KT, and shallow vestibules in the area from the mandibular left canine to the first molar. To address these challenges, we opted for a modified approach using an apically positioned full-thickness flap combined with a 7 mm wide ADM graft, eliminating the need for a donor site and improving structural stability.

At the nine-month follow-up, results showed a 4-5 mm increase in KT, enhanced vestibular depth, and favorable esthetics with satisfactory color matching. This technique provided both functional stability and esthetic satisfaction, making ADM grafting with a full-thickness flap a reliable option for KT reconstruction in esthetic zones.

This case report describes the 10-year follow-up of a root-end re-surgery in a 38-year-old woman patient who had symptomatic apical periodontitis and failed endodontic surgery in the upper left central incisor. Past dental history revealed root-end surgery with amalgam in that tooth, which continued to swell and discomfort after the surgery. Upon clinical/radiographic examination, she revealed a grossly compromised crown-to-root ratio of 3:1 with severe mobility of the tooth and apical radiolucency. After thorough treatment planning and patient consent, re-surgery was carried out with calcium-enriched mixture cement as a biocompatible root-end filling material. Postoperative care included strict occlusal management and instructions to the patient to avoid hard foods. At the 10-year follow-up, the tooth was functional, and complete periapical healing was evident with no recurrence of symptoms. This case illustrates the role of modern endodontic microsurgery, appropriate biomaterial selection, and meticulous surgical technique in the long-term success of even challenging cases.

Background and objectives: Trigeminal Neuralgia (TN) is a disabling neuropathic pain that can severely compromise the quality of life the patient. The current standard treatments for TN lack enough safety and efficacy; therefore, utilizing new remedies is mandatory. Photobiomodulation (PBM) is a novel treatment suggested for neuropathic pain, but we need more studies on using low-level laser to manage TN.

Materials and methods: 7 cases of primary confirmed TN were enrolled in this study. Diode laser (InGaAs) was utilized with 980 nm wavelength to irradiate the involved painful areas and trigger zones. Painful areas were irradiated intra and extraoral with the duration of 20 seconds and in osculation condition in continual wave (CW). The energy density of intra and extraoral irradiation was 4 j/cm² and 6 j/cm² respectively. Duration of treatment was about 3 weeks. VAS (Visual analogue scale) score was used as an outcome measure before and after treatment. Prior to enrollment, the VAS of self-reported pain of subjects was 10.

Results: VAS scores gradually decreased from the 4th session in all patients, as far as following 15th session. VAS scores in all patients were 1-2 degree at the end of third week of study. Along with PBM therapy, the dose of carbamazepine for pain management was reduced until the pain intensity was so low that it was not needed.

Conclusion: It seems that the PBM could be employed as adjuvant therapy for TN, but further study with precise laser dosing and more outcome measures are needed to apply this technology confidently.

Focal osteoporotic bone marrow defect (FOBMD) of the jaw is a radiolucent lesion that usually occurs in the mandibular molar region of a middle-aged female. Incisional biopsy is recommended for definite diagnosis and then no further treatment is needed. The prognosis is excellent. This paper presents a 40-year-old female with an asymptomatic well-defined corticated radiolucency in the anterior of the mandible discovered incidentally in a dental checkup. Histopathologic examination showed a fatty marrow and the diagnosis of FOBMD was made. FOBMD is seldom included in the differential diagnosis of jaw radiolucencies; therefore, dental practitioners should be familiar with the clinical, radiographic, and microscopic characteristics of this entity.

Background and objectives: In this study, we aimed to report histopathological evaluation of the underlying tissues in a case of premature Titanium mesh exposure and assess the rate of Titanium mesh (Ti-mesh) exposure in the literature and its effect on treatment outcomes when used as a barrier membrane in jaw-bone reconstruction.

Materials and methods: We reviewed articles that used Ti-mesh with/without grafting materials to reconstruct atrophic ridges both vertically and/or horizontally. Considering our inclusion criteria, 51 studies were included. All relevant RCTs, retrospective studies (cohorts and case-controls) and case-series were included but case-reports and review articles were excluded. Data regarding premature exposure rate, removal rate, associated bone loss, and implant survival rate were extracted. Later, a report of an early Ti-mesh exposure in anterior maxillary horizontal augmentation with autogenous bone graft and deproteinized bovine bone mineral in a 50-year-old female is presented with a histological study of the underlying soft tissue at the time of mesh removal.

Results: A total of 51 studies were included in the review. Among the 41 studies reporting exposure, 18 reported removal of membranes, of which 3 caused significant bone loss. In the obtained biopsy from the reported case, a connective tissue infiltrated with sporadic inflammatory cells covered with keratinized stratified squamous epithelium was observed.

Conclusion: Our results indicate the loss of outcomes (both bone loss and implant failure) may not be associated with Ti-mesh exposure, which could, along with the rate of exposure, help the clinician assess the relative risk of its application.

Keywords: Alveolar ridge augmentation, Guided bone regeneration, Bone graft, Titanium mesh, Exposure.

One of the most challenging issues in the field of dentistry is to decide whether to preserve or extract a compromised tooth with subgingival caries/crown fractures. Several patient-related factors (i.e. biological, behavioral, or financial factors), tooth-related factors (i.e. periodontal, endodontic, or restorative factors), and the role of the tooth in the overall treatment plan should be considered to make the most accurate decision. This article has focused on the decision-making process related to the management of compromised teeth with subgingival caries/crown fractures. Based on the current scientific evidence and clinical experience of the authors, an algorithm has been suggested to simplify this process of decision. In the first step, compromised teeth were classified as single-root or multi-root groups. “Crown-to-root ratio” (C/R ratio), and “apical extension of caries to the crestal bone” were considered the main clinical parameters in the decision-making process for single-root and multi-root teeth, respectively. We do not recommend restoring the compromised teeth if the C/R ratio is more than 1 (for single-root teeth) or if the extension of caries has reached the alveolar bone crest (for multi-root teeth). For maintainable single-root teeth, there are three treatment options to provide space for the re-establishment of supracrestal soft tissue attachment (previously named as biologic width) between the future restorative margin and underlying crestal bone. These approaches include: surgical crown lengthening (SCL), orthodontic forced eruption (OFE), and deep marginal elevation (DME). For multi-root teeth, SCL and DME are usually the procedures of choice. Multi-root teeth are not amenable to OFE due to the heavy orthodontic forces needed for extrusion. We also discussed the indications and limitations related to each treatment option. Further studies should be conducted to evaluate the external validity of this decision tree.

Keywords: Decision trees; Decision making; Tooth fractures; Dental caries; Tooth extraction.

Human dental pulp is a unique connective tissue able to respond to the invasion of pathogens and their by-products in the root canal system via inflammatory reactions in order to remove etiological factors and encourage healing; resulting in “Pulpitis”, which is namely defined by the accumulation of inflammatory mediators, specifically pro-inflammatory cytokines and chemokines. However, if the inflammation progresses and pathogens are not appropriately reduced or eliminated, pulp necrosis will ultimately occur; causing the need for radical pulpectomy and consequently, loss of tooth vitality. Vital pulp therapy (VPT), as a concrete example of regenerative endodontics, is based upon minimally invasive concept; in which the conservation of compromised or inflamed dental pulpal tissue is of critical importance for dentine-pulp regeneration. Pro-inflammatory cytokines, as host modulators, play a significant role in the amendment of intensity and duration of immune response to pathogenic factors. Since the modulation of inflammation is crucial in reaching successful outcomes in VPT, anti-cytokine therapy may assist in achieving the aforementioned results. In addition, when the amount of pro-inflammatory cytokines increases, the pulpal inflammation seems to escalate and negatively affect the tissue healing. Therefore, if cytokines are modulated, the inflammatory process can be favourably controlled, and the healing of dental pulp tissue may be promoted.

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