Assessment of fractal dimension changes in periapical trabecular patterns following single-visit and multi-visit nonsurgical endodontic treatment with different medicaments: a retrospective study

BackgroundThis study aimed to evaluate and compare periapical healing by analyzing the architecture of post-treatment trabecular bone using fractal analysis (FA) following mineral trioxide aggregate (MTA) apexification and regenerative endodontic treatment (RET), as well as to investigate the correlation between FA findings and Periapical Index (PAI).MethodsA total of 37 patients (20 treated with apexification and 17 with RET) were included in the study. All selected teeth were single-rooted maxillary anterior incisors. Patients were divided into two groups based on the treatment received: either apexification or RET. At 12-month follow-up, periapical radiographs were obtained. From the designated regions of interest (ROI) on these radiographs, fractal dimension (FD) values were calculated, and PAI assessed by two observers were recorded. The Wilcoxon test was used to assess differences in time changes between measurements. Differences between groups were evaluated using the Mann-Whitney U test. Statistical significance was set at p < 0.05.ResultsThere was a statistically significant difference between the FD of the ROI post-operatively and at follow-up in both, the apexification and the RET treatment groups (p < 0.001). No statistically significant difference was observed in the changes in FD at the 12-month follow-up between the apexification and the RET group (p > 0.05). In the apexification treatment group, a moderate negative correlation was observed between the changes in PAI and the changes in FD values (Spearman’s rho = − 0.444, p = 0.049), indicating that increases in trabecular bone complexity (higher FD values) were associated with lower PAI. In contrast, in the RET group no statistically significant correlation was found between the changes in PAI and the changes in FD values (p > 0.05).ConclusionBoth MTA apexification and RET support structural bone healing in the periapical region. FA offers an objective approach for quantifying changes in trabecular bone architecture and may enhance the radiographic assessment of periapical healing when used alongside conventional methods.Clinical trial numberNot applicable – retrospective analysis.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12903-025-07037-4.

This single-centre retrospective case-control study evaluated fractal dimension (FD) changes in radiographs of periapical lesions using a fractal analysis in healthy individuals and type 2 diabetes mellitus (DM) patients following root canal treatment. The study data consisted of two groups: the DM group which contained a total of 46 mandibular molar teeth in 37 patients with no systemic disease other than type 2 DM, and the control group which contained a total of 52 mandibular molar teeth in 41 patients without systemic disease. Periapical radiographs were obtained prior to root canal treatment and 1year post-treatment. Fractal analysis was performed by selecting a region of interest on the periapical radiographs. For both groups, the FD changes in lesion area were calculated and compared. In addition, periapical status was evaluated using the periapical index (PAI) scores on periapical radiographs for both groups. Data were analysed using dependent-sample t-test, independent-sample t-test, Wilcoxon signed-rank test and Mann-Whitney U-test. In both groups, FD values were increased significantly 1year post-treatment as compared with those prior to treatment (P<0.05). The time-dependent increase in FD was significantly greater in the control group (P<0.05). Time-dependent increases in FD did not differ between genders (P>0.05). There was a significant decrease in PAI scores in both type 2 DM and control groups depending on time (P<0.05). No significant difference was found between the groups in terms of time-related decreases in PAI scores (P>0.05). An increase in the FD of the periapical lesion area was observed 1year after root canal treatment. DM had a negative effect on FD increase.

Fractal analysis and periapical index evaluation of multivisit nonsurgical endodontic retreatment: A retrospective study

This study aimed to investigate 2-year changes in periapical trabecular patterns in single-rooted teeth with apical periodontitis using fractal analysis and periapical index (PAI) after root canal treatment performed with or without BioPure MTAD solution. In this randomized clinical trial, 100 patients were selected and randomized to either the BioPure MTAD or the control groups. Initial periapical radiographs were obtained for each participant before and 2 years after root canal treatment. The region of interest in the periapical lesion around the root apex was selected from the paired periapical radiographs, and then, the fractal dimension (FD) was calculated. With regards to the classification of periapical status, PAI was labelled as "healed" (PAI ≤ 2) or "unhealed" (PAI ≥ 3). After 24 months, 28 patients did not comply with the follow-up and the data of 72 patients were compared. When the initial and the follow-up PAI scores were compared, the decrease was statistically significant in 33 of 37 teeth (89.2%) and 32 of 35 teeth (91.4%) in the BioPure MTAD and control group, respectively. In both groups, statistically significant increases were observed in FD values after 2 years in all patients (p < .001). No significant difference was found between the two groups amongst decreased PAI scores and increased FD values. Root canal treatments with or without BioPure MTAD irrigation contributed to periapical healing in single-visit root canal treatment. Two years after root canal treatment, the extent of the periapical trabecular bone radiographically increased, as the FD and PAI data revealed.

Introduction:Fractal dimension (FD) on periapical radiographs is used as a simple descriptor of the complex architecture of the trabecular bone surrounding the dentition. It is used on periapical and panoramic radiographs as a descriptor of the complex architecture of trabecular bone surrounding teeth.Aim:The aim of this study was to evaluate the effect of image resolution and different compression levels on fractal dimension of alveolar bone with images obtained using storage phosphor plate (SPP) system.Methods:Periapical images of premolar and molar teeth on both sides of three dry human mandibles were obtained with Digora Optime (Soredex Corp., Helsinki, Finland) SPP system. The SPPs were exposed equally and scanned immediately after exposure with standard, high and very high resolutions. All the images then were compressed and saved by degrees of 0%, 25%, 50%, 75% and 90%. FD was calculated using public domain software (ImageJ with FracLac plug-in) on two non-overlapping regions of interest (ROIs) on premolar and molar periapical bone areas of each radiograph using differential box-counting method. The ROIs on corresponding images were of the same size and position. FDs were compared using two-way ANOVA and Tukey–Kramer multiple comparison tests (p=0.05).Results:There was no significant difference in FD calculations in different levels of compression for all the resolutions. Images obtained with high resolution scans showed significantly lower variation in FD values compared to very high and standard resolutions for all compressions (p<0.0001).Conclusion:The high resolution demonstrated the lowest variation in FD values in all levels of compression which makes it the most reliable and consistent resolution for measuring the FD values. The level of compression does not make a significant difference in FD values for all the scan resolutions. Scanning resolution of SPPs should be carefully chosen when evaluating the change in FD of alveolar bone for various bone disorders.

Aim. The aim of the present study was to determine the fractal dimension (FD) values of the cortex and white matter of the cerebral hemispheres using fractal analysis of two-dimensional magnetic resonance images, explore the anatomical correlations of the cortex and white matter FD, and study age-associated changes in the cortex and white matter. Methods. Two-dimensional brain magnetic resonance images of 100 apparently healthy individuals of both genders (44 males and 56 females) aged 18-86 years were studied. Five sections of each participant’s brain were selected (4 coronal and 1 axial). After image segmentation, the FD values and sectional areas of the cortex and white matter were determined. Fractal analysis was conducted using a two-dimensional variant of the box-counting method. Results. The FD values of the cortex and white matter varied across the five brain sections analyzed. Specifically, the cortex exhibited a decrease in the FD, whereas the white matter showed an increase in the FD in the coronal sections along the rostro-caudal direction. The FD values obtained from different sections displayed weak to moderate correlations. Additionally, no significant differences were observed in the FD values of the cortex and white matter between males and females. However, the sectional area values of the cortex and white matter were slightly higher in males as compared to females. Furthermore, a negative correlation was identified between the FD values of the cortex and white matter of the cerebral hemispheres, while sectional areas did not exhibit significant correlations. The cortex FD positively correlated with the gyrification index, whereas the white matter FD showed a negative correlation with this parameter. Additionally, both the FD and sectional area values of the cortex displayed strong and moderate negative correlations with age, respectively. In contrast, the FD and sectional area values of the white matter demonstrated weak negative correlations with age. Males showed stronger correlations of the studied parameters with age across the majority of the analyzed sections compared to females, although these differences were not statistically significant. Conclusions. In this study, a negative correlation was found between the cortex and white matter FD values, influenced by anatomical factors such as the degree of gyrification. While the cortex FD values significantly decreased with age, age-related changes in the white matter FD values were relatively weak.

Background and Objectives: This study retrospectively investigated the impact of regenerative endodontic treatments (RET) on the healing of periapical lesions in young permanent molars with open apices. Our objective was to evaluate the relationship between treatment outcomes and changes in the fractal dimension (FD) of the periapical bone before and after RET. The study was conducted at the Department of Pediatric Dentistry, Necmettin Erbakan University between January 2020 and December 2024. Materials and Methods: We examined panoramic radiographs from systematically healthy patients aged 6–16 years who underwent RET in the posterior mandible between January 2020 and December 2024. Changes in periapical bone were assessed using fractal analysis before treatment and after a 6-month follow-up. Additionally, mental index (MI), mandibular cortical width (MCW), mental length (ML), and periapical index (PAI) values were evaluated. Radiographs were taken with a Planmeca ProOne® device and analyzed using ImageJ v1.54 software. Results: Comparison of FD values between treated and contralateral tooth areas, as well as before and after RET, revealed an average FD value of 1.27 ± 0.05 after regeneration, increasing to 1.29 ± 0.27 at the 6-month follow-up. Significant increases were observed in MCW (p = 0.005/p = 0.049) and ML (p = 0.022/p = 0.001) in the 35–36 and 45–46 regions post-RET, though MI values showed no significant change. Importantly, PAI scores demonstrated significant improvement after RET. Conclusions: The findings suggest that RET is effective in promoting the healing of periapical lesions in young permanent molars. The observed increases in cortical width and improvements in PAI scores support the positive impact of this treatment on bone healing. Furthermore, FD analysis, when combined with radiomorphometric indices, could provide a valuable and objective tool for evaluating RET outcomes.

Background:Apical periodontitis (AP) is one of the most prevalent diseases of the teeth. Treatment of AP is based on the removal of the cause, i.e., bacteria from the root canals. Achievement of adequate bacterial eradication in one appointment treatment remains a controversy.Aim:This prospective study was conducted with the objective to compare the periapical healing of teeth with AP treated in (a) single visit versus (b) two visits, either with or without Vitapex as an intracanal medicament.Subjects and Methods:Patients were selected randomly from the Department of Conservative Dentistry and Endodontics. Forty-three patients (81 teeth) met the inclusion criteria, i.e., AP (both symptomatic and asymptomatic) visible radiographically size ≥2 mm × 2 mm, not suffering from any immune-compromising disease, age between 16 and 65 years and tooth not accessed previously. Patients were randomly divided into three groups, i.e., single-visit group (Group 1), multi-visit group without any intracanal medicament (Group 2), and multi-visit group with Vitapex as interim intracanal medicament (Group 3). Comparison was done radiographically using periapical index (PAI). The primary outcome measure was the change in periapical radiolucency after 1 year assessed by PAI scores. The Mann-Whitney U-test was used to evaluate differences between groups at baseline (immediate postoperative) and at the 12-month follow-up evaluation. Change in PAI score for each group from baseline to 12-month follow-up evaluation was tested with the Wilcoxon signed rank test. The secondary outcome measures, proportion of teeth in each group that could be considered improved (decreased PAI score) or healed (PAI <2), were assessed with the Chi-square test.Results:No statistically significant difference in periapical healing was found between three groups.Conclusion:After 1-year evaluation, no difference in periapical healing was found between single-visit treatment and multi-visit treatment groups with the given sample size.

ObjectivesProlotherapy is a method that has gained popularity in recent years and has been reported to have positive short-term and long-term clinical results in maxillofacial surgery, especially temporomandibular joint (TMJ) hypermobility. This study aimed to evaluate the changes in the trabecular structure of mandibular condyles in patients who underwent prolotherapy due to TMJ hypermobility using the fractal analysis method.Materials and MethodsForty-five patients who received dextrose prolotherapy at a concentration of 20% and fifteen control patients were included in the study. All patients had panoramic radiographs just before (T0) and six months after treatment (T1). The patients who received treatment were divided into three groups according to the number of prolotherapy injections. The regions of interest were selected from bone areas close to the articular surfaces of the condyles. The fractal dimension (FD) values were calculated.ResultsThe main effect of time on the FD value was significant [F (1, 56)=86.176, P<0.001]. This effect was qualified by a significant time×group interaction effect [F (3, 56)=9.023, P<0.001]. The decreases in FD values in all treatment groups between T0 and T1 times were significant (P=0.004). However, changes in FD values were not significant in the control group (P=0.728).ConclusionDextrose prolotherapy without the effect of the number of injections caused a decrease in FD values in the mandibular condyles over time.

Objectives: This study aimed to quantitatively evaluate the changes in the internal bone structure at the periapical bone regions after retreatment in endodontics using fractal analysis method on periapical radiographs. Materials and Methods: 29 single-rooted, asymptomatic, single-visit retreatment teeth with apical lesion were included in the study. All teeth included in the study were selected from the maxilla anterior region. Periapical radiograph (T0) was taken for baseline diagnosis at the start of retreatment. Second periapical follow-up radiograph (T1) of the patients was taken at the end of 1 year. The first evaluation phase of the 1-year results of endodontic retreatment is based on the periapical index (PAI). Fractal dimension (FD) was calculated by box-counting method. The paired-sample t-test was used to compare T0 and T1 FDs. The independent samples t-test was employed to compare FD changes between the sexes. The significance level was set to 0.05. Results: PAI scores were found to be statistically significantly decreased in T1 radiographs compared to T0 (p

A prospective cohort study aimed to assess the inhibitory effect of cigarette smoking on the rate of periapical bone healing after root canal treatment (RCT). Examination included both clinical and radiographic parameters to define healing status at baseline, 6 months, and 1 year after RCT. To examine and compare the healing rate of apical periodontitis (AP) after RCT between smokers and nonsmokers, and to evaluate how the intensity and duration of smoking affect AP healing up to 1-year follow-up. Study hypothesis was that smoking habits could delay or deteriorate AP healing. The study protocol was approved by the local ethics committee and all of the participants signed a consent form. Included were adult patients with a radiographically confirmed AP in a single tooth with a favorable periodontal prognosis and adequate coronal restoration, with no previous RCT. Excluded patients were those diagnosed with a systemic disease or on medications affecting bone metabolism, former and occasional smokers, pregnant patients, and those who refused to participate. Smokers were defined as those who consumed at least 100 cigarettes in their lifetime and currently smoke. Smoking intensity was classified according to cigarette consumption per day (CPD) into: heavy smoking (≥20 CPD) and mild smoking (˂20 CPD). Tobacco exposure over time was assessed by smoking index (=CPD ˟ duration of tobacco smoking in years) and categorized into: nonsmoker, <400, 400-799, and ≥800. The control group included healthy nonsmokers and matched the smoker group in termsof age and gender. All RCTs were performed by endodontic specialists following a standardized protocol. Clinical examination involved percussion and palpation tests, periodontal probing and examination of the coronal restoration; while the periapical healing was radiographically assessed using the periapical index (PAI) scoring. A total of 110 patients (55 smokers and 55 nonsmokers) were included. The two groups were comparable regarding age, gender, tooth type, socioeconomics, and periapical index scores at the baseline. The mean CPD among smokers was 12.22, and most of them were "mild smokers". At 12-month follow-up, nonsmokers showed a significantly higher healing rate compared to smokers (90.9% vs. 58.2%; χ2 = 13.846; p < 0.001). Conversely, smokers had significantly higher PAI when compared to the control group (p = 0.024). Regression analysis demonstrated that the risk of AP persistence increases with an increase in the smoking index [OR = 7.66; 95% CI: 2.51-23.28; p < 0.001, for smoking index <400 and (OR = 9.65; 95% CI: 1.45-64.14; p = 0.019, for smoking index 400-799]. Smoking was significantly associated with delayed AP healing after RCT. The likelihood of AP persistence rises as smoking exposure increases. These results could impact clinical decisions and guidelines concerning smokers.

Effect of the Time Interval of Functional Loading on the Periapical Healing of Endodontically Treated Mandibular Molar Teeth with Pulp Necrosis and Asymptomatic Apical Periodontitis: A Split-mouth Randomized Clinical Study

A comparison between mineral trioxide aggregate (MTA) apexification and regenerative endodontic therapy (RET) in immature permanent teeth is pivotal for optimising treatment outcomes and enhancing clinical decision-making. Understanding the efficacy, limitations and long-term implications of each approach is essential for achieving predictable, successful outcomes when managing immature teeth with necrotic pulps. The aim of this retrospective study was to compare the changes in the periapical bone using fractal dimension (FD) on the periapical radiographs of patients who underwent apexification and RET. The lesion area was evaluated using fractal analysis on periapical radiographs obtained before and one year after treatment with the ImageJ program. Additionally, periapical status was classified using the periapical index (PAI). The significance level was set at 0.05. In the present study, we found that the changes in FD and PAI over a one-year observation period were independent of the specific root canal treatment technique used. According to the fractal analysis, neither MTA apexification nor RET with tripleantibiotic paste is superior for immature teeth with pulp necrosis resulting from dental trauma.

Introduction The cysts of the maxillofacial region account for one of the most common pathologies of the head and neck region after the mucosal pathologies. Radiography provides an essential clue in early diagnosis and triaging, but it continues further as it is used to evaluate the post-treatment outcome. However, manual analysis is prone to errors. In this scenario, fractal analysis (FA) in radiographs uses mathematical methods to analyse the changes in grey scales in a given radiographic image. FA in odontogenic cysts is used to characterise their complexity, uncover hidden patterns, monitor treatment response, and potentially provide prognostic information. This paper aimed to assess the fractal characteristics of the radicular cyst (RC), dentigerous cyst (DC), and odontogenic keratocyst (OKC) using cone beam computed tomography (CBCT). The objective was to calculate fractal dimension (FD) values expressed in each of these cysts, which could prove to be a radiological adjunct in diagnosing the above cysts. Materials and methods As this is a retrospective study, the archives of CBCT images from June 2021 to December 2023 were obtained from patients diagnosed and confirmed with a histopathological diagnosis with RC, DC, and OKC. The FA was performed using Image J Software(Ver 1.51, National Institute ofHealth Bethesda, Fiji). The cortical and cancellous bones were segmented using thresholding techniques and converted to binary images. The mean FD of the three planes was then compared to establish the distinctive fractal characteristic for the specific odontogenic cysts. A one-way ANOVA was performed using the Statistical Product and Service Solutions (SPSS) (version 23.0; IBM SPSS Statistics for Windows, Armonk, NY) to determine the difference between FD values of RC, DC, and OKC with a significance level less than 0.05. Results The FD values of DC, RC, and OKC were 1.33 ± 0.17, 1.08 ± 0.16, and 1.65 ± 0.12, respectively. The results indicated that OKC had higher FD values than DC and RC, which means that OKC had lesser bone destruction compared to DC and RC. Inferential statistics showed that the one-way ANOVA was used to compare the means of the three groups of FD data. When calculated for the three groups, the F-statistic value was at 7.29, which yielded a P value of 0.03, making it statistically significant for a 95% confidence interval (p<0.05). Conclusion Our CBCT study on bone trabecular pattern analysis using FD and FAin odontogenic cysts reveals distinct alterations in bone parameters among different cyst types. The probability of higher FD values in OKC is because of lesser cortical bone destruction in OKC compared to the other cyst types. These findings have potential implications for diagnosing, treating, and prognosticating odontogenic cysts.

Objective The mere surgical removal of periapical granulomas through root-end surgery, without proper biomechanical preparation of the canal, placement of calcium hydroxide intracanal medicament, and obturation, does not result in the desired healing of periradicular tissues. The objective of this study was to determine the difference between injectable calcium hydroxide and powder/liquid calcium hydroxide in the resolution of pain (using the Numerical Pain Rating Scale) and periapical granulomas through periodic assessment and measurement of periapical radiolucency, radiographically and using periapical index (PAI) scores. Methods This six-month randomized controlled trial was conducted at the Restorative Unit of the National Hospital, Abuja, from 9 August 2018 to 10 February 2020. A total of 128 participants with 128 maxillary anterior teeth presenting with periapical granulomas and a PAI score of ≥4 with horizontal diameter ≥5 mm were recruited. They were randomly assigned to two groups: Group A (n=64) received proprietary injectable calcium hydroxide (Calasept), while Group B (n=64) received the powder/liquid mixture. Participants were recalled at 1 week post-treatment and then monthly for 6 months. Healing was assessed using periapical radiographs and PAI scores. Canals were redressed at 3 months. The primary outcome was lesion size reduction in millimeters and PAI score changes; the secondary outcome was pain resolution. Statistical analysis was performed using Student's t-test, regression analysis, and Friedman test with IBM SPSS version 20.0. A p-value &lt; 0.05 was considered significant. Results At 6 months, 100% of participants in both groups had resolution of pain symptoms. Both groups showed significant reduction in periapical lesion size from month 2 to month 6, with faster resolution in Group A. PAI scores significantly reduced in both groups at 6 months, with comparable scores throughout (P &lt; 0.05). Conclusion The findings suggest that both preparations of calcium hydroxide are effective, but the injectable form (Calasept) promotes faster resolution of lesions and symptoms.