Effects of melatonin against experimentally induced apical periodontitis in rats

Apical periodontitis is an inflammatory condition resulting from microbial invasion in the root canal system, causing periapical tissue destruction and bone resorption. This study investigated melatonin's effects, known for its antioxidant and anti-inflammatory properties, on experimentally induced apical periodontitis in rats. Three groups of rats were studied: control, apical periodontitis and apical periodontitis with melatonin treatment. Proinflammatory cytokines and enzyme levels in blood serum were measured, and micro-CT analysis assessed bone resorption. Results showed significantly elevated cytokines and enzyme levels in the apical periodontitis group compared to the control. However, in the melatonin-treated group, these levels were significantly reduced (p < 0.01-0.001). Micro-CT analysis indicated decreased periapical resorption cavity volume and surface area with melatonin treatment. This suggests that systemic melatonin administration can mitigate inflammation and reduce bone resorption in experimentally induced apical periodontitis in rats, potentially holding promise for human endodontic disease treatment pending further research.

Cone-beam-computed tomography evaluation of mandibular nutrient canals in patients with periodontal diseases

Background and Aim

The aim of this study was to evaluate radiographically the prevalence of mandibular nutrient canals (NCs) in patients with/without periodontal bone loss with aging and to correlate the number of NCs with the severity of bone loss using cone-beam-computed tomography (CBCT).

Patients and Methods

CBCT examinations of 208 patients were evaluated retrospectively of all patients, 114 had periodontal bone loss, whereas 94 patients were control subjects. Alveolar bone loss investigations were performed according to the Progressive Rate Index.

Results

NCs were observed in 55% of the control group and 86% of the periodontitis patients. NCs were more prevalent in the elderly age group with periodontal bone loss. In the study group, the NCs were statistically more frequent than in the control subjects (P > 0.05).

Conclusion

Statistical analysis showed a significant difference between the age groups and the prevalence of NCs increased in patients with periodontal alveolar bone loss with aging (P < 0.05).

Radıologıcal Evaluatıon of the Recesses on the Posterıor Wall of the Nasopharynx wıth Cone-beam Computed Tomography

Background

The posterior wall of the nasopharynx is composed of loose connective tissue that includes many important anatomical structures. Various structures, such as the opening of the Eustachian tube (ET), the Rosenmüller fossa (RF), and the pharyngeal bursa (PB) are found here.

Aim

To evaluate the nasopharynx posterior wall anatomic structures, including the Eustachian tube, Rosenmüller fossa, and pharyngeal bursa with cone-beam computed tomography.

Materials and Methods

The depth, width, and length of the Eustachian tube, Rosenmüller fossa, and pharyngeal bursa were measured in 150 patients using axial-sagittal cone-beam computed tomography. The Eustachian tube and Rosenmüller fossa distance to the midsagittal plane, the coronal region passing through the posterior end of the nasal septum, the superior-inferior extremity of the recesses, and the nasal floor plane distance were measured. The relationship between Rosenmüller fossa types and other parameters were evaluated.

Results

The incidence of right Rosenmüller fossa types 1, 2, and 3 were 16%, 18%, and 66%, respectively, and that of the left Rosenmüller fossa types 1, 2, and 3 were 16%, 19.3%, and 64.7%, respectively. The mean pharyngeal bursa width, length, and depth were 10.8, 5.7, and 4.0 mm, respectively; those of the Eustachian tube were 5.6, 7.1, and 7.3 m, respectively; those of the right Rosenmüller fossa were 4.0, 12.4, and 10.5 mm, respectively; and those of the left Rosenmüller fossa were 3.8, 12.5, and 10.9 mm, respectively.

Conclusions

The posterior wall of the nasopharynx contains several important anatomical structures. Evaluation of these using cone-beam computed tomography has many clinical and radiological advantages. To understand and interpret the coincidental findings in CBCT, dental radiologists should have access to more detailed information concerning the anatomy of the nasopharynx.

Gray value measurement for the evaluation of local alveolar bone density around impacted maxillary canine teeth using cone beam computed tomography

Background

To investigate whether any relationship between local alveolar bone density and maxillary canine impaction using gray values from cone beam computed tomography.

Material and Methods

The cone beam computed tomography images of 151 patients were retrospectively evaluated. Maxillary canine was defined as an impacted tooth when root formation was complete and the patient’s age older than 13 or the other side of the maxillary canine has completely erupted. Similarly, complete eruption was defined as the tooth in its expected occlusion and position. Using the cone beam computed tomography software, the region of interest which was 5 mm2 in area, was placed in the trabecular bone on cross sectional cone beam computed tomography images and the gray value measurements were recorded. After measuring the gray values of all the teeth, the images were grouped according to the field of view size. Comparison of the gray values of impacted and non-impacted teeth was made between images with the same field of view size.

Results

A total of 151 patients, 101 (66.9%) female and 50 (33.1%) male, were included in the study. The mean age of the patients was 24.94 ±13.9. In images with a 40X40 field of view, the gray values of the impacted canine teeth were higher than the gray values of the non-impacted ones and statistically significant difference was found between them (p=0.003). However no statistically significant difference was found between the gray values of impacted and non-impacted canine teeth in 60x60 and 100x50 field of view (p=0.197, p=0.170, respectively).

Conclusions

We suggest using the smallest field of view size when evaluating bone density using gray values from cone beam computed tomography images and we support the idea that the local increased bone density may influence on impaction.

Key words:Cone-beam computed tomography, tooth, impacted, bone density, maxilla, image processing, computer-assisted.

Effects of Preheating and Sonic Delivery Techniques on the Internal Adaptation of Bulk-fill Resin Composites

CLINICAL RELEVANCE

The internal adaptation of resin composites that are recommended to be placed with the conventional insertion technique could be improved when the resin composites are preheated prior to their placement. SonicFill 2 and VisCalor bulk show the best internal adaptation when they are inserted as per the manufacurer's recommended techniques.

SUMMARY

Objective: To compare the effects of conventional (hand-placed), sonic, or preheated insertion techniques on the internal adaptation of bulk-fill resin composites.Methods and Materials: A total of 150 freshly extracted human third molars were used to prepare standardized cylindrical occlusal cavities. Teeth were divided into five main groups according to the resin composites: 1 incremental (Clearfil Majesty Posterior [CMP]) and four paste-like bulk-fill (SonicFill 2 [SF2], VisCalor bulk [VCB], Filtek One bulk-fill restorative [FBR], and Tetric EvoCeram bulk-fill [TEB]). Each main group was divided into three subgroups according to the placement technique: conventional, preheating, and sonic delivery (n=10). In the conventional placement technique, cavities were filled manually. In the sonic insertion technique, a specific handpiece (SonicFill Handpiece; Kerr Corporation) was used. In the preheating technique, a heating device (Caps Warmer, Voco, Cuxhaven, Germany) was used to warm the resin composites before placement. Internal voids (%) of the completed restorations were calculated with microcomputed tomography. Data was analyzed with two-way analysis of variacne followed by Tukey's multiple comparisons test (α=0.05).Results: All resin composites showed fewer internal gaps with preheating compared with the conventional placement (p<0.05). For all resin composites other than SF2, preheating provided fewer internal gaps than that of the sonic placement (p<0.05). Sonic placement led to fewer internal gaps compared with the conventional placement, but only for SF2 and FBR (p<0.05). For the conventional placement, the lowest gap percentage was observed with the incremental resin composite (CMP, p<0.05). Among all groups, the lowest gap percentages were observed for preheated VCB followed by sonically inserted SF2 (p<0.05).Conclusion: The best internal adaptation was observed in sonically inserted SF2 and preheated VCB, which were the manufacturers' recommended insertion techniques. Preheating considerably improved the internal adaptation of all resin composites, except for that of SF2.

Evaluation of the relationship between tympanic plate morphology and degenerative bone changes of condyle and articular eminence

INTRODUCTION

This study aimed to evaluate the relationship between tympanic plate morphology and degeneration of temporomandibular joint (TMJ) condyle and articular eminence (AE).

MATERIAL AND METHODS

Cone beam computed tomography images of 700 patients (345 males, 355 females) were evaluated. The prevalence and location of tympanic plate pneumatization (TPP) and foramen tympanicum (FT) were recorded. Sagittal scans of the TMJs were classified according to the degenerative bone changes of condyle and AE (flattening, osteophytes, erosion, sclerosis, and subcortical cysts).

RESULTS

TPP was found in 106 of 700 patients (15.2%) while FT was found in 165 (23.2%) of the patients. TPP and FT were bilateral in 52 (49.1%) patients and 46 (27.9%) patients, respectively. The mean axial diameter of FT was 2.53mm and the mean sagittal diameter was 2.52mm. The most common degenerative changes for condyle and AE were flattening.

CONCLUSION

To know these structures is important for surgical operations in the region of TMJ and ear to prevent complications. CBCT is useful to evaluate these anatomical landmarks and the relationship between them and the degenerative bone changes of condyle and AE.

The agreement between magnetic resonance imaging and arthroscopic findings in temporomandibular joint disorders

The aim of this retrospective observational study was to assess the potential agreement between independent magnetic resonance imaging (MRI) and arthroscopic findings and their respective contributions to a final diagnosis in patients with refractory temporomandibular joint disorders. Two dentomaxillofacial radiologists and two oral and maxillofacial surgeons scored 50 joints. All observers, who were blinded to additional clinical information, used a specific scoring form and selected one or more diagnostic labels. Agreement between MRI and arthroscopy and their contributions to the final diagnosis were assessed as primary outcomes using Fleiss' kappa. Intra-modality agreement and the correlation between signal intensity ratio (SIR) measurements on MRI and synovitis grading on arthroscopy were assessed as secondary outcomes. Agreement between MRI and arthroscopy was poor. A fair level of agreement was only reached for reduction capacity of the disc and disc perforation. Arthroscopic diagnostic labels matched better with the final diagnosis, suggesting a bigger contribution to that diagnosis. Higher SIR measurements correlated with higher synovitis grading scores for the retrodiscal tissue and the posterior band of the disc. Intra-modality agreement was better in arthroscopy. When blinded to clinical information, arthroscopy and MRI observations can lead to different conclusions. The diagnostic outcomes of both examinations should be considered and integrated into a final diagnosis.

Publication trends in micro-CT endodontic research: a bibliometric analysis over a 25-year period

AIM

To conduct a bibliographic analysis of the research studies published in Endodontics using micro-computed tomography (micro-CT) as an analytical tool over a 25-year period.

METHODOLOGY

The Web of Science electronic database was accessed, and an advanced search using strict criteria was undertaken from January 1995 to June 2020 for studies in the field of Endodontics that used micro-CT as an analytical tool. A further search was conducted between January and August of 2020 for a combination of specific terms and descriptors. For each selected article, the following parameters were recorded: field of the study, analysed specimen, publication title and year, authorship, journal of publication, institution and country of origin, collaborating institutions and countries, and number of citations. The acquired data were analysed using descriptive statistics and graphical mappings.

RESULTS

The screening process identified 877 relevant articles that were classified into 30 thematic categories. The main fields of research were root canal preparation (23.8%), root canal anatomy (17.4%), canal filling (9.2%) and root canal retreatment (7.0%). The most productive half-decade comprised the period of 2015-2019 (n = 513; 58.5%), with the highest number of articles published in 2019 (n = 146; 16.6%). The authors who lead the list as first authors were G De-Deus, A Keleş, F Paqué, MA Versiani and Y Gu, respectively, whilst Versiani was the most productive (n = 51). The leading countries regarding the number of studies were Brazil, China and Turkey with 236, 130 and 65 publications, respectively. The University of São Paulo (n = 90; 10.3%) followed by Wuhan University (n = 37; 4.2%) and the University of Zurich (n = 18; 2.1%) were the prominent contributors by producing the largest number of articles, whilst the University of Zurich was the most-cited institution. The selected studies were published in 140 scientific journals, but the Journal of Endodontics and International Endodontic Journal accounted for almost 50% of the publications.

CONCLUSION

This bibliometric analysis portrayed an original and comprehensive view on the progress and trends of the use of micro-CT technology in endodontic research, and enabled a deep understanding of the development process in this field over the last 25 years.

Evaluation of long-term hard tissue relapse following surgical-orthodontic treatment in skeletal class II patients: A systematic review and meta-analysis

This systematic review and meta-analysis was performed to evaluate the long-term hard tissue stability and relapse factors following surgical-orthodontic treatment in skeletal class II patients. A literature search was conducted using Embase, Cochrane Central, Web of Science, and PubMed, yielding 3184 articles published up to January 2019. Risk of bias was assessed following the Cochrane handbook. Ten articles met the inclusion criteria. A total of 1079 patients were followed up for 5-13 years. The qualitative findings showed a variety of extrinsic and intrinsic factors affecting long-term stability. Meta-analysis for the amount and direction of cephalometric landmark displacement in the vertical and sagittal planes showed significant angular increases of ANB and backward relapse of SNB, however within the clinically acceptable range of 4°. In relation to linear measurements, the mean differences in all landmarks were within the clinically acceptable range of 2mm except for gonion. In conclusion, this systematic review showed multiple intrinsic and extrinsic factors responsible for relapse. However, the outcomes of the meta-analysis are limited due to the heterogeneity of data, small number of studies, and inconsistent methods of evaluation. Further high-quality studies utilising standardised three-dimensional methodologies are required to improve the level of evidence.

The effect of type 2 diabetes mellitus on changes in the fractal dimension of periapical lesion in teeth after root canal treatment: a fractal analysis study

AIM

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.

METHODOLOGY

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 1 year 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.

RESULTS

In both groups, FD values were increased significantly 1 year 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).

CONCLUSION

An increase in the FD of the periapical lesion area was observed 1 year after root canal treatment. DM had a negative effect on FD increase.

Semi-automatic magnetic resonance imaging based orbital fat volumetry: reliability and correlation with computed tomography

Post-processing analysis can provide valuable information for diagnosis and planning of orbital disorders. This cross-sectional study aims to evaluate the reliability of semi-automatic, orbital fat volumetry using magnetic resonance imaging (MRI). Two observers assessed the orbital fat volume using a standard MRI protocol (3T, T1w sequence) in 12 orbits diagnosed with Graves' orbitopathy (GO) and 10 healthy control orbits. MRI and computed tomography (CT) based analysis were compared. Intra-observer variability was good (intraclass correlation coefficient (ICC) 0.88; 95% confidence interval (CI) [0.70, 0.95]) and interobserver agreement was moderate (ICC 0.55; 95% CI [-0.09, 0.81]), which corresponds to a mean percentage difference of 1.3% and 17.9% of the total orbital fat volume. Mean differences between MRI and CT measurements were, respectively, 1.1 cm³ (P= 0.064, 95% CI [-0.20, 2.43]) and 1.4 cm³ (P=0.016, 95% CI [0.21, 2.56]) for the control and the GO group. MRI volumetry was strongly correlated with CT (Pearson's r= 0.7, P<0.001). We conclude that orbital fat volumetry is feasible with a semi-automatic segmentation procedure and standard MRI protocol. Correlation with CT volumetry is good, but considerable bias may derive from observer variability and these errors should be taken into account for the purpose of volumetric analysis. Better definition of error sources may increase measurement accuracy.

Evaluation of artificial intelligence for detecting periapical pathosis on cone-beam computed tomography scans

AIM

To verify the diagnostic performance of an artificial intelligence system based on the deep convolutional neural network method to detect periapical pathosis on cone-beam computed tomography (CBCT) images.

METHODOLOGY

images of 153 periapical lesions obtained from 109 patients were included. The specific area of the jaw and teeth associated with the periapical lesions were then determined by a human observer. Lesion volumes were calculated using the manual segmentation methods using Fujifilm-Synapse 3D software (Fujifilm Medical Systems, Tokyo, Japan). The neural network was then used to determine (i) whether the lesion could be detected; (ii) if the lesion was detected, where it was localized (maxilla, mandible or specific tooth); and (iii) lesion volume. Manual segmentation and artificial intelligence (AI) (Diagnocat Inc., San Francisco, CA, USA) methods were compared using Wilcoxon signed rank test and Bland-Altman analysis.

RESULTS

The deep convolutional neural network system was successful in detecting teeth and numbering specific teeth. Only one tooth was incorrectly identified. The AI system was able to detect 142 of a total of 153 periapical lesions. The reliability of correctly detecting a periapical lesion was 92.8%. The deep convolutional neural network volumetric measurements of the lesions were similar to those with manual segmentation. There was no significant difference between the two measurement methods (P > 0.05).

CONCLUSIONS

Volume measurements performed by humans and by AI systems were comparable to each other. AI systems based on deep learning methods can be useful for detecting periapical pathosis on CBCT images for clinical application.

Three-dimensional volumetric analysis of the maxillary sinus: a cone-beam computed tomography study

BACKGROUND

This study aimed to determine the volumetric size of the maxillary sinus and investigate the effect of gender and age on maxillary sinus volume (MSV) using cone-beam computed tomography (CBCT) images in a Turkish subpopulation.

MATERIALS AND METHODS

This retrospective volumetric CBCT study was carried out on 133 individuals (84 females, 49 males) between 8 and 51 years old. MSV was measured using the MIMICS 21.0 software (Materialise HQ Technologielaan, Leuven, Belgium). All statistical analyses were performed using the SPSS 21.0 (SPSS, Chicago, IL, USA) software. Mean and standard deviation of both maxillary sinuses measurements were calculated and compared to gender and age. P values < 0.05 were considered to indicate statistical significance.

RESULTS

Mean volume of the right maxillary sinus was 13.173 cm3, while for the left was 13.194 cm3. There was no significant difference between right and left maxillary sinus volumes (p > 0.05). There was no significant correlation between MSV and age (p > 0.05). It was found that MSV did not change according to gender (p > 0.05).

CONCLUSIONS

Right and left maxillary sinus volumes were not different from each other. Gender and age were not found to be related to maxillary sinus volume.

Volumetric Cuspal Deflection of Premolars Restored With Different Paste-like Bulk-fill Resin Composites Evaluated by Microcomputed Tomography

OBJECTIVES

The aim of this study was to measure the volumetric cuspal deflection of premolars restored with different paste-like bulk-fill resin composites using microcomputed tomography (micro-CT).

METHODS AND MATERIALS

A total of 35 freshly extracted human maxillary second premolars were selected for this study. Standardized large MOD cavities were prepared in each premolar with a bucco-lingual width of 4 mm and a cavity depth of 4 mm measured from the palatal cusp tip. After cavity preparation, all samples were scanned immediately using a micro-CT system. After the initial micro-CT scanning, restorative procedures were performed. Four groups received different paste-like bulk-fill composites-Beautifil-Bulk Restorative (BBR), Admira Fusion x-tra (AFX), x-tra fill, and Sonic Fill-and the control group received a conventional universal composite and Clearfil Majesty Esthetic (CME). Immediately after the restorative procedure, each tooth was scanned by micro-CT in the same manner as the initial scanning. The buccal and palatal regions of each restoration were evaluated separately in terms of cuspal deflection. One-way analysis of variance was used to compare the effect of the composite resin, and multiple comparisons were performed by the Tukey test with a level of significance of α = 0.05.

RESULTS AND DISCUSSION

Multiple comparisons showed that teeth restored with the conventional paste-like composite and CME (control) had significantly different cuspal deflection from those filled with paste-like bulk-fill composites (p<0.05). Among the bulk-fill composites, a significant difference was observed between BBR and AFX (p<0.05).

CONCLUSIONS

Paste-like bulk-fill resin composites had significantly lower cuspal deflection than the conventional paste-like resin composite tested.

Effects of alpha-lipoic acid therapy on experimentally induced apical periodontitis: a biochemical, histopathological and micro-CT analysis

AIM

To investigate the possible therapeutic effects of alpha-lipoic acid (ALA) in a model of chronic apical periodontitis in rats by analysing biochemical, histopathological and micro-CT parameters.

METHODOLOGY

The study was approved by the Animal Ethics Committee of the Near East University. Thirty-two Wistar rats were divided into four groups of eight rats each: Control Group; ALA Group; AP Group; AP + ALA Group. In the AP and AP + ALA groups, the pulp chambers of the mandibular first molars were surgically exposed and were left open to the oral environment for 4-weeks to allow the establishment of periapical lesions. The rats in the Control and AP groups were treated intraperitoneally with saline solution (with a daily dose of 100 mg kg^-1 , for 28 days after periapical lesion induction). The rats in the ALA and AP + ALA groups were treated intraperitoneally with ALA (with a daily dose of 100 mg kg^-1 , for 28 days after periapical lesion induction). After decapitation, the trunk blood was collected for the assessment of biochemical parameters. The mandibles were surgically removed and dissected for histopathologic analysis and further scanned with micro-CT. Groups of data were compared with a two-way analysis of variance (two-way anova) followed by Sidak's multiple comparison tests. Values of P < 0.05 were regarded as significant.

RESULTS

TNF-α, IL-1β, MMP-1, MMP-2 levels were significantly lower in AP + ALA group compared with AP group (P < 0.05). There was a significant difference between the AP and AP + ALA groups according to assessment of the inflammatory scores (P < 0.05). The periapical inflammatory infiltrates were significantly more severe (P < 0.05) in the AP group. The AP + ALA group exhibited lower values both in terms of surface area and volume of resorption cavities than the AP group and this difference was significant (P < 0.05).

CONCLUSION

alpha-lipoic acid treatment provided therapeutic effects on the inhibition of periapical bone loss.

Evaluation of the relationship between stylohyoid complex morphology and maxillary/mandibular position using cone beam computed tomography

BACKGROUND

The aim of this study was to examine the morphologic features of the stylohyoid complex (SHC) and its relation to maxillomandibular position using three-dimensional cone beam computed tomography (CBCT) images.

MATERIALS AND METHODS

CBCT images from 157 individuals (74 females, 83 males) were analysed in this study. SHC length, width, and sagittal and transverse angles were measured. The subjects were grouped as skeletal class I, II, and III in order to determine the relative positions of the maxilla and mandible in the sagittal plane and as hypodivergent, normodivergent, and hyperdivergent according to the vertical rotation of the mandible in relation to the skull base. Mann-Whitney U and Kruskal-Wallis H tests were used for statistical analysis.

RESULTS

Mean SHC length was 23.56 ± 8.05 mm on the right side and 22.0 ± 6.51 mm on the left; mean SHC width was 3.31 ± 1.40 mm on the right and 2.93 ± 1.30 mm on the left. Mean sagittal angle was 27.43 ± 6.75° on the right side, 27.70 ± 6.51° on the left; mean transverse angle was 70.39 ± 4.59° on the right side and 71.79 ± 4.99° on the left. The only significant difference based on skeletal classification was greater SHC length among males compared to females in the class III group (p < 0.05).

CONCLUSIONS

No significant relationship was observed between SHC morphology and position of the maxilla or mandible. However, the gender difference observed among class III subjects suggests that SHC morphology may be affected by craniofacial morphology. Maxillofacial surgeons should investigate this anatomical landmark variation before surgical interventions involving this region, such as temporomandibular joint procedures.

Assessment of paranasal sinus parameters according to ancient skulls' gender and age by using cone-beam computed tomography

BACKGROUND

The aim of this study was to determine whether paranasal sinus dimensions and volume can be useful to identify gender and age estimation for ancient skulls using cone-beam computed tomography (CBCT) images.

MATERIALS AND METHODS

CBCT scans of 32 ancient skulls of approximately 1000 years of age were included in this retrospective study. The gender and age estimation of the skulls were made by an independent anthropologist, which was considered as the gold standard. Paranasal sinuses' dimensions (width and height) and volumes of each sinus were measured from the CBCT data set that was linked to the three-dimensional rendering software (Anatomage, Invivo 5.2). All measurements were performed by an independent observer. Intra-observer analysis was made. Mann-Whitney and Kruskal-Wallis tests were used to compare paranasal sinus parameters in terms of age estimation and gender (p < 0.05).

RESULTS

The results demonstrated no statistically significant difference between measurements (p < 0.05). The measurements were found to be highly reprodu- cible. The mean volumes of frontal and sphenoid sinus were found to be higher in males. The distance from anterior-posterior wall of sphenoid sinus in axial sec- tions is larger in males (p > 0.05). The frontal sinus width and volume increased statistically with age above 60 years of age (p > 0.05).

CONCLUSIONS

The paranasal volume and dimensions' measurements from CBCT data can be a promising technique to determine gender and age of ancient skulls because of its lower voxel sizes and higher resolution.

Anatomical characteristics of the lingual foramen in ancient skulls: a cone beam computed tomography study in an Anatolian population

BACKGROUND

The purpose of this study is to evaluate the anatomical features of lingual foramina and their bony canals in Anatolian ancient mandibles (9-10th century) by using cone beam computed tomography (CBCT).

MATERIALS AND METHODS

Fifty-eight ancient dry mandibles were scanned with CBCT. Lingual foramina were grouped into midline, paramedian, posterior foramina and combination of these groups. Midline group was also classified according to internal surface of the mandible (gonial tubercles [GTs]). The incidence, vertical distance and diameter of lingual foramina were measured according to age groups and gender.

RESULTS

The incidence of the lingual foramen was 96.6%. Midline of the symphysis had the highest incidence (34.4%) of foramina (p < 0.05), followed by both midline and paramedian type (32.8%; p < 0.05). Classification in terms of GT represented class 3 as the most encountered group (28.6%). Number of foramina observed in the mandibles ranged from 0 to 6 with the incidence of 3.4% and 32.8%, respectively. The male and < 35 years groups presented larger measurement values in midline region (p < 0.05).

CONCLUSIONS

Mandibular lingual foramina and bony canals are frequently present in ancient mandibles. When compared with modern subjects, similar findings are observed according to published literatures. CBCT is also proved to be an effective imaging modality in the detection of lingual foramina and canals in anthropological studies.

Evaluation of hyaluronic matrix efficacy in sinus augmentation: a randomized-controlled histomorphometric and micro-computed tomography analysis

The objective of the present study was to test the hypothesis that the addition of hyaluronic acid-based matrix to collagenated heterologous bone graft for sinus augmentation would enhance bone formation compared to collagenated heterologous bone graft alone in the early healing period, by micro-computed tomography and histomorphometry. Thirteen systemically healthy patients requiring bilateral two-stage maxillary sinus augmentation (residual crest height≤4mm) were enrolled in this split-mouth prospective randomized controlled study. One sinus side as a control group was grafted with only collagenated heterologous bone graft; the other region as a test group was grafted with hyaluronic matrix and collagenated heterologous bone graft. Bone biopsy samples were taken after 4 months during the dental implant surgery and analyzed using micro-computed tomography and histomorphometric parameters. According to the micro-computed tomography and histomorphometric results, a significantly higher percentage of new bone was observed in the test group when compared to the control group after 4 months of healing. This study confirmed the hypothesis that the addition of hyaluronic matrix to collagenated heterologous bone graft for sinus augmentation enhances bone formation compared to collagenated heterologous bone graft alone in the early healing period.

Analysis of pulp chamber of primary maxillary second molars using 3D micro-CT system: an in vitro study

AIM

The aim of this study was to determine the positional relationship between the crown contour and the pulp chamber as well as the morphological characteristics of the pulp chamber using micro-CT in order to plan, in restorations of deciduous maxillary second molars, reconstructions with a volumetric rendering programme.

STUDY DESIGN

In total 16 deciduous maxillary second molar teeth (8 from boys, 8 from girls) were used. The positional relationship between crown contour and pulp chamber was three-dimensionally observed by micro-CT. Differences in sex, dentin thickness and pulp volumes were evaluated using chi-square and paired t-tests. Differences were considered significant when P < 0.05.

RESULTS

Dentin thickness was found to be 2.8 mm ± 0.2, mesiobuccally 3.15 mm ± 0.2 distobuccally 3.8 ± 0.3, which was statistically significant (p ≤ 0.05). The pulp volume for boys was 77 mm³ ± 4, for girls 64 mm³ ± 5, with a statistical significance (p ≤ 0.05).

CONCLUSIONS

General differences could play a role when planning a treatment for a child; however for both genders it should be noted that mesiobuccal pulp horn is most likely to get exposed during cavity preparation.

Comparison of the influence of FOV sizes and different voxel resolutions for the assessment of periodontal defects

OBJECTIVES

This study assessed the influence of different voxel resolutions of two different CBCT units on the in vitro detection of periodontal defects.

METHODS

The study used 12 dry skulls with a maxilla and a mandible. Artificial defects (dehiscence, tunnel, fenestration) were separately created on the anterior, premolar and molar teeth using burrs. A total of 14 dehiscences, 13 fenestrations, 8 tunnels and 16 non-defect controls were used in the study. Images were obtained from two different CBCT units in six voxel sizes (voxel size: 0.080, 0.100, 0.125, 0.150, 0.160 and 0.200 mm3). Kappa coefficients were calculated to assess both intra- and interobserver agreements for each image set.

RESULTS

Overall intraobserver kappa coefficients ranged between 0.978 and 0.973 for the 0.080-mm3 images and between 0.751 and 0.737 for the 0.160-mm3 images, suggesting notably high intraobserver agreement for detecting periodontal defects. CBCT performed significantly better at detecting fenestrations (p<0.05) than tunnel and dehiscence defects. No statistically significant difference was found between the detection of dehiscence and tunnel defects (p>0.05).

CONCLUSIONS

A voxel size of 0.150 mm3 was identified as the cut-off point for overall detection of periodontal defects. CBCT should be considered the most reliable imaging modality for the diagnosis of periodontal defects.

Case report: multiple keratocystic odontogenic tumour in a non-syndromal pediatric patient

BACKGROUND

Keratocystic odontogenic tumour (KCOT) is an odontogenic tumour which stems from the odontogenic organs mostly localised in the lower jaw, particularly posterior body and ascending ramus of the mandible. The majority of these tumours are single lesions. When detected in the jaw in multiple forms, these cysts are seen in association with Gorlin Goltz/Basal cell naevus syndrome. However a few cases of non-syndromal multiple keratocystic odontogenic tumour have been reported in the literature.

CASE REPORT

We report a case of multiple keratocystic odontogenic tumour in a 13-year-old girl demonstrated by panoramic radiography and cone beam computed tomography (CBCT). The differential diagnosis, treatment and imaging modalities are also discussed.

Evaluation of articular eminence pneumatization using cone beam computed tomography

AIM

Knowledge about the anatomy of the temporomandibular joint (TMJ) and its surrounding structures is mandatory for success in surgical interventions and for understanding the pathway of spread of infections in this region. This study aims to investigate the anatomy and morphology of pneumatized articular eminence (PAT) using cone beam computed tomography (CBCT) imaging in a group of patients.

METHODS

A retrospective study on 825 patients (377 males, 448 females) aged between 18 and 91 years was performed using sagittal and coronal CBCT images. PAT was defined as non-expansile, nondestructive cyst-like radiolucency in the zygomatic process of the temporal bone, which appears similar to the mastoid air cells. It was classified in two groups as unilocular and multilocular. Statistical comparison of gender, age and localization was performed using chi-square test and correspondence analysis. P<0.05 was considered as significant.

RESULTS

Twenty-eight pneumatized articular eminence were found in 21 patients, representing a prevalence of 2.54%. Patients with PAT had a mean age of 28.9 years with a range of 21-78 years. Ten cases (47.6%) occurred in females and 11 cases (52.4%) occurred in males. The results of statistical tests showed no significant differences among the groups with respect to gender, age, and localization (P>0.05).

CONCLUSION

Pneumatization of the articular eminence is a challenging entity for TMJ surgery and spread of infections in this region. Practitioners who are dealing with TMJ surgery and pathology should have detailed information about this anatomical variation since it may cause serious complications.

Comparison of linear and angular measurements using two-dimensional conventional methods and three-dimensional cone beam CT images reconstructed from a volumetric rendering program in vivo

OBJECTIVE

The aim of this study was to compare the linear and angular measurements made on two-dimensional (2D) conventional cephalometric images and three-dimensional (3D) cone beam CT (CBCT) generated cephalograms derived from a 3D volumetric rendering program.

METHODS

Pre-treatment cephalometric digital radiographs of 11 patients and their corresponding CBCT images were randomly selected. The digital cephalometric radiographs were traced using Vista Dent OC (GAC International, Inc Bohemia, NY) and by hand. CBCT and Maxilim® (Medicim, Sint-Niklass, Belgium) software were used to generate cephalograms from the CBCT data set that were then linked to the 3D hard-tissue surface representations. In total, 16 cephalometric landmarks were identified and 18 widely used measurements (11 linear and 7 angular) were performed by 2 independent observers. Intraobserver reliability was assessed by calculating intraclass correlation coefficients (ICC), interobserver reliability was assessed with Student t-test and analysis of variance (ANOVA). Mann-Whitney U-tests and Kruskal-Wallis H tests were also used to compare the three methods (P < 0.05).

RESULTS

The results demonstrated no statistically significant difference between interobserver analyses for CBCT-generated cephalograms (P < 0.05), except for Gonion-Menton (Go-Me) and Condylion-Gnathion (Co-Gn). Intraobserver examinations showed low ICCs, which was an indication of poor reproducibility for Go-Me and Sella-Nasion (S-N) in CBCT-generated cephalograms and poor reproducibility for Articulare-Gonion (Ar-Go) in the 2D hand tracing method (P < 0.05). No statistical significance was found for Vista Dent OC measurements (P > 0.05).

CONCLUSIONS

Measurements from in vivo CBCT-generated cephalograms from Maxilim® software were found to be similar to conventional images. Thus, owing to higher radiation exposure, CBCT examinations should only be used when the inherent 3D information could improve the outcome of treatment.

Dentin hypersensitivity: a randomized clinical comparison of three different agents in a short-term treatment period

OBJECTIVE

Dentin hypersensitivity, or what patients may describe as "sensitive teeth," is defined as a short, sharp pain arising from exposed dentin in response to thermal, evaporative, tactile, electrical, osmotic or chemical stimuli. It is widely accepted that dentin hypersensitivity is an uncomfortable condition that also affects function and quality of life. This study determines the differences in efficiency of three desensitizing products when compared with a placebo.

METHODS

A randomized controlled clinical trial was conducted to compare three different professional dentin desensitizer agents in 52 patients. The age and sex of the patients was recorded. Gluma Desensitizer (Heraeus Kulzer), UltraEZ (Ultradent Products, Inc) and Duraphat (Colgate Oral Pharmaceuticals, Inc, New York, NY, USA) were used as desensitizer agents and distilled water was used as the placebo. The baseline measurement of the dentin hypersensitivity was made by using a visual analog scale (VAS). Twenty-four hours and seven days after application of the desensitizer agents and placebo, a new VAS analysis was conducted for patients' sensitivity level. The desensitizer agents were compared in terms of mean values, and ANOVA was used for testing differences among the groups (p<0.05).

RESULTS

The results showed that the mean pain scores of the placebo group were significantly higher than that of the study groups (p<0.05). The VAS analysis revealed a significant decrease in dentin hypersensitivity over time with the use of agents (p<0.05). No statistically significant difference was found among the three desensitizing agents (p>0.05).

CONCLUSIONS

These three desensitizing agents, which contain different active ingredients, were effective in relieving dentin hypersensitivity. However, no superiority was found in dentin sensitivity relief among the agents.

Magnetic resonance imaging evaluation of mandibular condyle bone marrow and temporomandibular joint disc signal intensity in anaemia patients

OBJECTIVES

To compare the signal intensity (SI) of mandibular condyle bone marrow (MCBM) and the temporomandibular joint (TMJ) disc in patients with chronic anaemia and healthy subjects, and to investigate the relationships between bone marrow changes, age, types of anaemia and severity of anaemia.

METHODS

MRIs of 18 patients with chronic anaemia were compared with those of 12 healthy subjects. The SI of MCBM and the TMJ disc were quantitatively evaluated. The SI of the grey matter (GM), white matter (WM) and the lateral pterygoid muscle were also investigated. Relationships between age, MCBM and TMJ disc signal-intensities and anaemia severity, and correlations between the groups, were analysed.

RESULTS

The mean MCBM SI was lower in anaemia patients (including both subgroups and also separately) than in healthy subjects (P < 0.05). No statistical significance was found for GM, WM and the muscle SI between the anaemia patients and healthy patient group (P > 0.05). No statistical significance was found between the groups with respect to the anterior band, whereas the mean SI value of the posterior band in the study group was significantly lower than in healthy subjects (P < 0.05). There were no correlations between age and MCBM SI, or between anaemia severity and MCBM SI.

CONCLUSIONS

Anaemia may cause bone marrow alterations without any internal derangement. Patients with chronic anaemia exhibit lower mandibular condyle bone marrow and posterior band SI than healthy subjects.

Radiographic evaluation of third molar development in relation to chronological age among Turkish children and youth

A sharp increase in forensic age estimation of living persons has been observed in recent years. However, ethnic populations residing in different countries have been insufficiently analyzed. According to 2004 data compiled by the Essen-based Turkey Research Center, there are 3.8 million Turkish people living abroad, and 3.2 million of them reside in European Union countries. Despite the high number of Turks living abroad, little is known about third-molar development for forensic application in this population. Hence, it was considered worthwhile to determine the developmental stages of the third molar in a group of Turkish population, to assess chronological age estimation based on the developmental stages, and to compare third molar development according to sex, age and location. Orthopantomograms of 1134 Turkish patients, ages 4-20 years were examined and third-molar developmental stages were evaluated based on Demirjian's classifications. Orthopantomograms were scored by two different observers, and Wilcoxon matched-pairs signed-ranks test used to test intra- and inter-observer reliability revealed a strong agreement between both intra- and inter-observer measurements. Linear regression analysis was performed to correlate third-molar development and chronological age, and further statistical analysis was performed to determine the relation between sex, age and location. Results showed a strong linear correlation between age and molar development (males: r(2)=0.57; females: r(2)=0.56). Mineralizations of left and right third molars were compared using Wilcoxon tests, and no statistical differences were found. No significant differences were found in third-molar development between males and females. Mandibular third molar crypt formation was observed in 2.4% of patients at age seven and maxillary third molar crypt formation was observed in 1.3% of patients at age seven. A strong correlation was found between third-molar development and chronological age. Among the Turkish population, third molar crypt formation is observable at as early as 7 years in both the mandible and maxilla. Agenesis can be determined conclusively if no radiolucent bud is present by age 14.

Radiographic evaluation of pneumatized articular eminence in a group of Turkish children

OBJECTIVES

The purpose of this study was to determine the prevalence and characteristics of patients with pneumatized articular eminence (PAT) in a group of Turkish children in order to make a contribution to pneumatization phenomenon in childhood.

METHODS

1049 panoramic radiographs were retrospectively evaluated. PAT was defined as non-expansile, non-destructive cyst-like radiolucency in the zygomatic process of the temporal bone, which appears similar to the mastoid air cells. It was classified as unilocular or multilocular on the radiograph. Statistical comparison of gender, age and localization was performed using a chi-square test (P<0.05).

RESULTS

Twenty-four pneumatized articular eminences were found in 17 patients, representing a prevalence of 1.62%. Patients with pneumatized articular eminence had a mean age of 11.2 (SD 3.13) years with a range of 7-16 years. Eight cases (47.1%) occurred in girls and nine cases (52.9%) occurred in boys. The results of statistical tests showed no statistically significant differences among the groups with respect to gender, age and localization (P<0.05).

CONCLUSIONS

Pneumatization of accessory air cells begins before puberty, contrary to the general opinion and statements. Knowledge about these structures is helpful for the interpretation of imaging such as panoramic radiographs and provides valuable information to understand the spread and differential diagnosis of pathological entities in this region.