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1.
Oral Radiol ; 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-38625432

ABSTRACT

OBJECTIVE: This study aimed to evaluate the usability of morphometric features obtained from mandibular panoramic radiographs in gender determination using machine learning algorithms. MATERIALS AND METHODS: High-resolution radiographs of 200 patients aged 20-77 (41.0 ± 12.7) were included in the study. Twelve different morphometric measurements were extracted from each digital panoramic radiography included in the study. These measurements were used as features in the machine learning phase in which six different machine learning algorithms were used (k-nearest neighbor, decision trees, support vector machines, naive Bayes, linear discrimination analysis, and neural networks). To evaluate the reliability, we have performed tenfold cross-validation and we repeated this 10 times for every classification process. This process enhances the reliability of the results for other datasets. RESULTS: When all 12 features are used together, the accuracy rate is found to be 82.6 ± 0.5%. The classification accuracies are also compared using each feature alone. Three features that give the highest accuracy are coronoid height (80.9 ± 0.9%), condyle height (78.2 ± 0.5%), and ramus height (77.2 ± 0.4%), respectively. When compared to the classification algorithms, the highest accuracy was obtained with the naive Bayes algorithm with a rate of 84.0 ± 0.4%. CONCLUSION: Machine learning techniques can accurately determine gender by analyzing mandibular morphometric structures from digital panoramic radiographs. The most precise results are achieved by evaluating the structures in combination, using attributes obtained from applying the MRMR algorithm to all features.

3.
J Orofac Orthop ; 2024 Jan 22.
Article in English | MEDLINE | ID: mdl-38252312

ABSTRACT

PURPOSE: The goal of this work was to assess the classification of maturation stage using artificial intelligence (AI) classifiers. METHODS: Hand-wrist radiographs (HWRs) from 1067 individuals aged between 7 and 18 years were included. Fifteen regions of interest were selected for fractal dimension (FD) analysis. Five predictive models with different inputs were created (model 1: only FD; model 2: FD and Chapman sesamoid stage; model 3: FD, age, and sex; model 4: FD, Chapman sesamoid stage, age, and sex; model 5: Chapman sesamoid stage, age, and sex). The target diagnoses were accelerating growth velocity, very high growth velocity, and decreasing growth velocity. Four AI algorithms were applied: multilayer perceptron (MLP), support vector machine (SVM), gradient boosting machine (GBM) and C 5.0 decision tree classifier. RESULTS: All AI algorithms except for C 5.0 yielded similar overall predictive accuracies for the five models. In order from lowest to highest, the predictive accuracies of the models were as follows: model 1 < model 3 < model 2 < model 5 < model 4. The highest overall F1 score, which was used instead of accuracy especially for models with unbalanced data, was obtained for models 1, 2, and 3 based on SVM, for model 4 based on MLP, and for model 5 based on C 5.0. Adding Chapman sesamoid stage, chronologic age, and sex as additional inputs to the FD values significantly increased the F1 score. CONCLUSION: Applying FD analysis to HWRs is not sufficient to predict maturation stage in growing patients but can be considered a growth rate prediction method if combined with the Chapman sesamoid stage, age, and sex.

4.
Dent Med Probl ; 60(3): 393-400, 2023.
Article in English | MEDLINE | ID: mdl-37796046

ABSTRACT

BACKGROUND: Osseous dysplasia (OD) is a form of fibro-osseous lesion located in the jaws that may interfere with the adjacent anatomical structures. OBJECTIVES: The aim of the present study was to evaluate the distribution of radiographic imaging features, the morphological characteristics and the lesion volume of OD with the use of cone-beam computed tomography (CBCT). MATERIAL AND METHODS: The study included radiologically diagnosed lesions followed up for at least 1 year. The prevalence and distribution of the OD types were defined in terms of age, sex, lesion location, teeth, relationship with the anatomical structures, and lesion volume. RESULTS: The mean age gradually increased from the periapical group to the florid group (p = 0.018). It was observed that the mandible was the most frequently affected bone (85.5%) (p < 0.05). The margins of the lesions were well defined, and had an irregular or circular shape. The buccal cortical bone was the most affected structure (84.5%), and the damage in the cortical bone increased with an increase in the lesion volume. With regard to teeth, the most frequent disorder was a discontinuous lamina dura (83.0%). CONCLUSIONS: Osseous dysplasia lesions affect a wide range of different anatomical areas, and show different volume and morphometric characteristics.


Subject(s)
Odontogenic Tumors , Humans , Retrospective Studies , Radiography , Cone-Beam Computed Tomography , Mandible/diagnostic imaging
5.
Anat Sci Int ; 98(3): 454-462, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37079264

ABSTRACT

This study purposed to develop statistical models to predict palatal (PRL), mesial (MRL), and distal (DRL) root canal length and pulp volume (PV) of the maxillary first permanent molar using stature, gender, mesiodistal (MD), and buccopalatal (BP) crown diameters and some facial morphometries. 57 individuals were included in the study. Cone beam computed tomography was used to measure root canal lengths and PV. The PV calculation was carried out using the software ITK-SNAP 3.4.0. PRL was positively correlated with BP, stature, middle facial height, interalar distance, and bicommissural distance (BCD) (p < 0.05). DRL was positively correlated with BP, MD, and stature (p < 0.05). MRL was positively correlated with BP, MD, stature, lower face height, bizygomatic distance, and BCD (p < 0.05). PV was negatively correlated with age and BCD (p < 0.05). Although all models have significant predictive power for the root lengths and PV, no model could explain variances greater than 30%. The highest and lowest predictive ability was obtained for PRL and DRL, respectively. While the most significant predictor was BP for PRL and DRL, it was the age for PV.


Subject(s)
Tooth Root , Tooth , Humans , Dental Pulp Cavity/diagnostic imaging , Molar/diagnostic imaging , Cone-Beam Computed Tomography/methods , Maxilla/diagnostic imaging
6.
Article in English | MEDLINE | ID: mdl-36328893

ABSTRACT

OBJECTIVE: The aim was to perform fractal analysis (FA) to compare differences in trabecular microarchitecture in interdental and antegonial regions on panoramic radiographs in periodontally healthy patients and those with stage III/IV, grade C periodontitis, and to compare the effects of patient age and sex on FA results. STUDY DESIGN: Clinical and radiographic records from 33 periodontally healthy individuals and 28 individuals with aggressive periodontitis were obtained from the faculty archives. Three regions of interest (ROIs) were chosen bilaterally from interdental bone around the mandibular first molar and canine and the antegonial region. The mean fractal dimension (FD) values of the ROIs were calculated. Significance of differences was established at P < .05. RESULTS: FD values of all 3 ROIs in the periodontitis group were significantly lower than values in the control group (P ≤ .004). FD was not affected by patient age (P = .357) or sex (P = .216). There were no significant correlations between FD and age in either group (P ≥ .093). FD values differed significantly between sexes in only one ROI. CONCLUSIONS: FA can effectively detect trabecular microarchitectural differences in patients with aggressive periodontitis compared to periodontally healthy individuals. This technique might be useful in predicting the susceptibility of patients to periodontal disease.


Subject(s)
Aggressive Periodontitis , Humans , Aggressive Periodontitis/diagnostic imaging , Fractals , Cancellous Bone/diagnostic imaging , Mandible/diagnostic imaging , Periodontium/diagnostic imaging , Radiography, Panoramic/methods
7.
Article in English | MEDLINE | ID: mdl-36333196

ABSTRACT

OBJECTIVES: This study investigated differences in trabecular structure and mandibular cortical thickness in adults related to vertical facial type (VFT), sex, and their interactions. STUDY DESIGN: Lateral cephalometric radiographs (LCRs) and panoramic radiographs (PRs) of 256 patients were reviewed. The VFT classification into low-angle, normal, and high-angle groups was determined using angular and linear measurements on LCRs. Fractal dimension (FD) values and mandibular radiomorphometric indices (RMIs) were calculated on PRs. RESULTS: Two-way analysis of variance revealed significant differences in FD overall among VFT groups in all sites (P < .001), with pairwise comparisons indicating the greatest values in the high-angle group in the condyle (P < .05) but in the low-angle group elsewhere (P < .001). RMIs were significantly different overall regarding VFT only in the posterior mandible (P = .004), with pairwise comparisons revealing low-angle and normal group values greater than high-angle group values (P < .05). Patient sex and the interaction of facial type and sex had no significant effect on any bone measurements. CONCLUSIONS: VFT had significant effects on trabecular structure at all measured sites, but cortical thickness was affected only in 1 location.


Subject(s)
Cancellous Bone , Mandible , Humans , Adult , Cancellous Bone/diagnostic imaging , Mandible/diagnostic imaging , Face/diagnostic imaging , Radiography, Panoramic/methods , Cephalometry , Fractals
8.
Eur Oral Res ; 56(2): 67-73, 2022 May 05.
Article in English | MEDLINE | ID: mdl-36003843

ABSTRACT

Purpose: The movement of chewing affects the growth and development of the stomatognathic system. Tooth decay, which is known to have effects on chewing, can affect the jaw bone due to its indirect effect on the mechanical forces transmitted to the jaw bone. This study aimed to evaluate the relationship between dental caries and jawbone trabeculation during the growth and development processes in children using fractal dimension (FD) analysis. Materials and methods: A total of 120 patients were divided into three groups. The groups were determined as follows: group 1: 40 patients without deep dentin caries/apical rarefying osteitis, group 2: 40 patients with deep dentin caries/apical rarefying osteitis on the right or left sides, and group 3: 40 patients with deep dentin caries/apical rarefying osteitis on both the right and left side. Digital panoramic images of the selected patients were evaluated using FD analysis. Results: There was no statistically significant difference in the FD analysis among the groups. Age and sex factors were not found statistically significant in the in-group evaluation (p>0.05). In group 3, FD values of the right condyle (r= -0.42, p<0.05), right ramus (r= -0.37, p<0.05) and left ramus (r= -0.45, p<0.05) were negatively correlated with age. Conclusion: There is no relationship between tooth decay and trabeculation of the jawbone in children aged 8-13 years.

9.
Clin Oral Investig ; 26(11): 6539-6549, 2022 Nov.
Article in English | MEDLINE | ID: mdl-35776204

ABSTRACT

OBJECTIVES: To investigate the knowledge, beliefs, and attitudes towards pediatric dental radiography and its associated factors among Turkish parents seeking dental care for their children. MATERIALS AND METHODS: This cross-sectional study enrolled 483 parents of children aged 6-15 years. Data were collected using the questionnaire including socio-demographic characteristics, knowledge, beliefs, and attitudes based on The Health Belief Model and planned behavior theory. Descriptive, bivariate, and multivariate statistics were performed. RESULTS: More than half of parents had correct knowledge on their rights to access health information, the radiation risk and exposure from dental X-rays, children's vulnerability to radiation, and using lead apron. Most parents (70.4%) perceived dental X-rays as valuable. They had limited knowledge regarding the permanent damage and negative attitudes regarding its safety and goodness. There were positive correlations between knowledge-attitudes, knowledge-perceived benefits, and attitudes-perceived benefits (all p values < 0.01). Having a previous dental X-ray (p = 0.014) and not having parents' information needs (p = 0.007) were associated with higher attitudes. Increasing education levels, having a educational need and higher perceived benefit were found to be predictors of higher parental knowledge. CONCLUSION: Turkish parents had some knowledge and positive attitudes towards pediatric dental X-rays but not at optimum levels. Parents' education levels, information needs, and beliefs were the most important factors affecting parental knowledge. Attitudes towards radiation safety and goodness should be improved. CLINICAL RELEVANCE: These findings may provide useful insight to clinicians when developing theory-driven health education interventions on pediatric dental X-rays and identifiying the parents with low knowledge.


Subject(s)
Health Knowledge, Attitudes, Practice , Parents , Child , Humans , X-Rays , Cross-Sectional Studies , Surveys and Questionnaires
10.
Aust Endod J ; 48(3): 431-443, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35690589

ABSTRACT

The purpose of this study was to evaluate the technical treatment quality and the status of apical pathology of endodontically treated teeth, as well as apical periodontitis (AP) prevalence, in a Turkish population using cone-beam computed tomography (CBCT). The CBCT images obtained between January 2018 and April 2020 were retrospectively examined. The quality of the endodontic treatments and the related periapical inflammatory lesions were classified according to the periapical and endodontic status scale (PESS). The data were statistically analysed using logistic regression, crosstabs and chi-square tests. AP was detected in 41% of 429 endodontically treated teeth. The prevalence of AP was significantly higher in teeth with inadequate root canal treatment compared with those with adequate treatment, 70.8% and 29.3%, respectively. Inadequate canal length and homogeneity, and complications were significantly associated with the prognostic periapical status scores of higher risk.


Subject(s)
Periapical Periodontitis , Tooth, Nonvital , Humans , Tooth, Nonvital/diagnostic imaging , Retrospective Studies , Periapical Periodontitis/diagnostic imaging , Periapical Periodontitis/therapy , Cone-Beam Computed Tomography/methods , Root Canal Therapy
12.
Oral Radiol ; 38(3): 398-404, 2022 07.
Article in English | MEDLINE | ID: mdl-34554390

ABSTRACT

OBJECTIVES: To perform a detailed analysis of palatal process pneumatization (PPP) on cone beam computed tomography (CBCT) images. METHODS: This study consisted of 376 maxillary sinuses of 188 patients aged 22-88 years who had maxillary CBCT scans. The radioanatomy of the PPP was evaluated at distances 4, 8, 16, and 24 mm posterior to incisive foramen. The types of PPP were classified as follows: type I: maxillary sinus palatal process non-gasified; type II: palatal process gasification into the nasal floor, but not more than half of the width of the nasal floor; and type III: palatal process gasification into the nasal floor more than half of the width of nasal floor. Sinus opening angle (SOA), palatonasal recess angle (PNRA), palatal junction angle (PJA), and palatal depth measurement (PDM) were the evaluated parameters. RESULTS: Among the identified 1315 PPPs, type I PPP (880, 66.92%) was the most frequently observed, followed by type II (426, 32.4%), and the least observed was type III PPP (9, 0.68%). There was no significant difference between SOA and PJA according to the types of PPP (p > 0.05). The difference between PNRA and PDM of type I and type II PPP showed a statistically significant difference (p < 0.05). Type I PPP was the most encountered with the highest PDM, and PNRA was narrower in type III than in type II PPP. CONCLUSION: Physicians must be aware of these variations to prevent possible complications during surgery because 33.08% of the maxillary sinuses showed extensive pneumatization through the palatal process.


Subject(s)
Cone-Beam Computed Tomography , Maxillary Sinus , Cone-Beam Computed Tomography/methods , Humans , Maxilla/anatomy & histology , Maxillary Sinus/anatomy & histology , Maxillary Sinus/diagnostic imaging
13.
Oral Radiol ; 38(1): 63-71, 2022 01.
Article in English | MEDLINE | ID: mdl-33870446

ABSTRACT

OBJECTIVE: To investigate mandibular morphologic measurements and trabecular structures that may cause mandibular third molar (MM3) impaction according to MM3 subgroups. METHODS: A total of 150 MM3 of 2175 panoramic radiographs (PRs) were reviewed. MM3s according to Winter (vertical), Pell & Gregory Class 1 and group: A, B, C on PRs were included in the study group. Fractal dimensions (FD) and mandibular morphologic measurements were evaluated. Statistical analysis for parametric values was performed using one-way analysis of variance (ANOVA). Statistical analysis for non-parametric values was performed using the Kruskal-Wallis H test. RESULTS: Statistically, a significant difference was found only in terms of angle of impaction among the groups of MM3 (p < 0.05) [Winter (vertical), and Pell & Gregory Class 1 and group A, B, C]. There was no difference among groups A, B, C in mandibular morphology and trabecular structure, but group C showed different characteristics than the other groups only in terms of impaction angle. CONCLUSION: The trabecular structure and morphometric properties except for the angle of impaction do not affect impacted MM3s with adequate retromolar space and vertical angle.


Subject(s)
Mandible , Molar , Fractals , Mandible/diagnostic imaging , Radiography, Panoramic
14.
Oral Radiol ; 38(3): 416-421, 2022 07.
Article in English | MEDLINE | ID: mdl-34714510

ABSTRACT

OBJECTIVE: To evaluate the presence of occipital spurs, morphologic/morphometric features, and the presence of ossification of ligamentum nuchae (ONL) on lateral cephalometric radiographs of individuals aged under and over 18 years. METHODS: Lateral cephalometric radiographs of 1430 individuals aged between 14-50 years were scanned. The presence of ONL and occipital spurs was evaluated in 1312 patients who met the inclusion criteria, and existing occipital spurs were measured and their types (flat/crest/spine) were recorded. RESULTS: Occipital spurs were detected in 63 patients aged over 18 years (63/120; 52.5%) and 57 patients aged under 18 years (57/120; 47.5%). When the spur length by age category and sex was evaluated, no statistically significant difference was observed. The spur types seen were flat (40.8%; 49/120), crest (30%; 36/120) and spine (29.2%; 35/120), respectively. Although there was no statistically significant difference between the spur types seen in terms of age, a significant difference was observed between the sexes in the total group (p < 0.001). Spine-type spurs (66.7%; 18/27) were the most common in females, and flat-type spurs (45.2%; 42/39) were the most common in males. ONL was detected in only three individuals. CONCLUSION: No relationship was found between the presence of occipital spurs and ONL. Although spur length was not affected by age and sex, spur types were found to vary according to sex. Occipital spurs are mostly asymptomatic and detected incidentally on lateral cephalometric radiographs. They are one of the important anatomic formations that should be diagnosed by physicians.


Subject(s)
Radiography , Adolescent , Adult , Cephalometry , Female , Humans , Male , Middle Aged , Young Adult
15.
J Prosthet Dent ; 126(6): 793.e1-793.e5, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34674841

ABSTRACT

STATEMENT OF PROBLEM: Dental prosthetic materials can cause artifacts in cone beam computed tomography (CBCT) images, adversely affecting diagnostic quality, although the problem may be less with polyetheretherketone (PEEK). Studies evaluating the artifacts caused by frequently used prosthetic materials are lacking. PURPOSE: The purpose of this in vitro study was to compare the artifacts in CBCT images caused by PEEK, zirconia, cobalt-chromium (Co-Cr) alloy, and titanium (Ti). MATERIAL AND METHODS: A polymethylmethacrylate phantom (Ø4.0×4.0 cm) with a central cylindrical aperture (Ø0.5×0.5 cm) was produced. Co-Cr, Ti, zirconia, and PEEK cylinders (0.5×0.5 cm) were manufactured, and CBCT images of the empty phantom (control group) with the test cylinders inside were made 3 times. In all images, the axial sections passing through the middle of the materials were evaluated. Eight regions of interest (ROI) area were determined around the materials (0.5×0.5 cm). The presence of artifacts was evaluated by making gray value standard deviation (SD) calculations in these ROI areas. The average SD values of 8 ROI fields from the 3 CBCT scans were made, and the materials were compared with each other in terms of the presence of artifacts by using 1-way analysis of variance (α=.05). RESULTS: The difference between the SD values of the control and the PEEK cylinder was not statistically significant (P>.05). The SD values of both the control and PEEK groups were significantly lower than those of the zirconia, Co-Cr, and Ti groups (P<.05). CONCLUSIONS: Zirconia, Ti, and Co-Cr caused artifacts in CBCT images, but the artifacts with PEEK were similar to those in the control group, suggesting it was the optimal choice in terms of achieving diagnostic quality.


Subject(s)
Artifacts , Cone-Beam Computed Tomography , Benzophenones , Phantoms, Imaging , Polymers , Titanium
16.
J Periodontal Res ; 56(6): 1058-1069, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34328646

ABSTRACT

BACKGROUND/OBJECTIVES: Obesity and periodontitis are systemic subclinical inflammatory diseases with established negative renal effects. The aim of this animal study was to thoroughly investigate the possible effects of these two diseases on renal structure and function. METHODS: Thirty-two male Sprague Dawley rats were divided into four groups: control (C), obesity (Ob), experimental periodontitis (Ep), and Ob + Ep. The first 16 weeks of the experiment were aimed for the induction of obesity and the last 5 weeks for the induction of periodontitis. Throughout the experimental period, the C and Ep groups were fed standard rat chow, while the Ob groups (Ob and Ob + Ep) were fed high-fat rat chow. Right after the establishment of obesity, periodontal tissue destruction was achieved by placing 3.0 silk sutures in sub-paramarginal position around the cervices of mandibular right-left first molar teeth and preserving them for 5 weeks. On the last day of the 22nd week, following blood collection, all rats were euthanized, and kidneys and mandibles were collected. Alveolar bone loss was measured on microcomputed tomographic slices. Histopathological evaluations (light microscopy, semi-quantitative analysis of renal corpuscle area, and immunohistochemical analysis of caspase-3 activity) were done on right kidneys and biochemical evaluations (malonyl-aldehyde [MDA], glutathione [GSH], total oxidant status [TOS], total antioxidant status [TAS], oxidative stress [OSI], tumor necrosis factor-α [TNF-α], interleukin-1ß [IL-1ß], matrix metalloproteinase [MMP]-8, MMP-9, and cathepsin D [CtD] levels) were done on left kidneys. Renal functional status was evaluated with levels of serum creatinine, urea, and cystatin C. RESULTS: Periodontal bone loss was significantly higher in the Ep and Ob + Ep groups, compared with the C and Ob groups (p < .05). All parameters except TAS and GSH were highest in the Ob + Ep group, and the differences were statistically significant compared with the control group (p < .05). Although the mean TAS and GSH levels were lower in the Ob + Ep group than the other groups, the differences were not statistically significant (p > .05). While the atypical glomeruli score was significantly higher in the Ob + Ep group than in all other groups (p < .05), the acute tubular necrosis and histopathological scores were significantly different only compared with the control group (p < .05). CONCLUSION: This experimental study showed that the negative effects of the co-existence of periodontitis and obesity on inflammatory stress and apoptotic changes in the kidneys together with the functional parameters were significantly more severe, compared with the presence of one of these diseases alone. TNF-α could have a central role in the periodontitis and obesity-related structural and functional renal changes.


Subject(s)
Alveolar Bone Loss , Periodontitis , Alveolar Bone Loss/diagnostic imaging , Alveolar Bone Loss/etiology , Animals , Kidney/diagnostic imaging , Male , Obesity/complications , Periodontitis/complications , Rats , Rats, Sprague-Dawley
17.
J Oral Maxillofac Surg ; 79(9): 1891.e1-1891.e4, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34153259

ABSTRACT

Oil-based contrast medium agents (Iofendylate) are cleared from cerebrospinal fluid very slowly. But it may remain within the tissues of the central nervous system. These substances, which were used for purposes such as myelography, cisternography, and ventriculography approximately 70 years ago and were replaced by water-soluble agents after thirty years, can rarely be detected incidentally. In this report, by presenting the intracranial radiopacities seen in 2 patients, it is aimed to increase awareness that these myeloid residues, which are rarely seen in panoramic radiography, can be diagnosed by clinicians.


Subject(s)
Incidental Findings , Myelography , Angiography , Contrast Media , Humans , Radiography, Panoramic
18.
Oral Radiol ; 37(3): 443-451, 2021 07.
Article in English | MEDLINE | ID: mdl-32803678

ABSTRACT

OBJECTIVES: To evaluate the relation between taurodontism and C-shaped configuration, as well as the prevalence and classification according to sex, left/right position, and arc length in the mandibular premolar and molar teeth using cone beam computed tomography (CBCT). METHODS: The presence of taurodontism and C-shaped configuration were evaluated using CBCT scans and classified by two independent radiologists. The sex, location in the jaw (left-right), and mandibular arc length measurements were recorded. The Chi-square test was used to determine the presence of taurodontism and C-shape configuration according to sex, left/right location, and independent-sample t tests were used to assess the relation between the arc length. RESULTS: The prevalence of taurodontism was significantly higher in the female population, whereas the C-shaped configuration was more frequent in males (p < 0.05). In both sexes, the most common type was hypotaurodont (7.5%). In the molars, the prevalence was significantly higher in second molars, and the most common C-shaped configuration type was C3 (39.3%). The prevalence was significantly higher in the first premolar, with C2 (22.4%) being the most frequent type in the premolars (p < 0.05). The arc length and location in the jaw were not significantly affected (p > 0.05). CONCLUSIONS: A high correlation was revealed between taurodontism and complicated C-shape canal configurations. Practitioners should be very careful about the presence of C-shape morphology in taurodontism treatment, and various types of C-shaped morphology ranging from coronal to the apical direction.


Subject(s)
Mandible , Tooth Root , Bicuspid/diagnostic imaging , Dental Pulp Cavity/abnormalities , Female , Humans , Male , Mandible/diagnostic imaging , Molar/diagnostic imaging , Tooth Abnormalities
19.
J Periodontol ; 91(11): 1486-1494, 2020 11.
Article in English | MEDLINE | ID: mdl-32279321

ABSTRACT

BACKGROUND: The aim of this experimental rat study was to investigate the potential inflammatory effects of periodontitis on cardiac left ventricular tissue and the therapeutic activity of melatonin on these effects. METHODS: Twenty-four male Sprague-Dawley rats were randomly divided into three groups: control, experimental periodontitis (Ep), and Ep-melatonin (Ep-Mel). Experimental periodontitis was induced by placing and maintaining 3.0 silk ligatures at a peri marginal position on the left and right mandibular first molars for 5 weeks. Afterward, following the removal of ligatures, melatonin (10 mg/body weight) to Ep-Mel group, and vehicle (saline) to Ep and control groups were administered intraperitoneally for 14 days. On the first day of the eighth week, mandibular and cardiac left ventricular tissue samples were obtained following the euthanasia of the rats in all groups. Alveolar bone loss measurements were made on histological and microcomputed tomographic slices. Cardiac tissue levels of malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), matrix metalloproteinase-9 (MMP-9), and cardiac Troponin-T (cTnT) were evaluated by appropriate biochemical methods. RESULTS: Measurements made on the histological and microcomputed tomographic slices showed that melatonin significantly limits the ligature-induced periodontal tissue destruction (P <0.01). In addition, melatonin was detected to cause a significant decrease of MDA, MMP-9, and cTnT levels which were found to be significantly higher on rats with Ep (P <0.05) while having no significant effect on antioxidant levels (GSH, SOD, and CAT) (P >0.05). CONCLUSION: Melatonin might be regarded as an important supportive therapeutic agent to reduce the early degenerative changes and possible hypertrophic remodeling at cardiac left ventricular tissues provoked by periodontitis-related bacteria and/or periodontal inflammation.


Subject(s)
Alveolar Bone Loss , Melatonin , Periodontitis , Alveolar Bone Loss/drug therapy , Alveolar Bone Loss/prevention & control , Animals , Antioxidants/therapeutic use , Male , Melatonin/therapeutic use , Periodontitis/complications , Periodontitis/drug therapy , Rats , Rats, Sprague-Dawley
20.
Biomed Res Int ; 2017: 8652720, 2017.
Article in English | MEDLINE | ID: mdl-29238725

ABSTRACT

PURPOSE: Friction-style and spring-style torque wrenches are used to tighten implant abutments and prosthetic screws. The mechanical stability of these torque wrenches is crucial for the implant-abutment connection. The purposes of this study were to assess the performance of five brands (Straumann, Zimmer, Implant KA, Bredent, and Biohorizons) of wrench and to evaluate possible changes in applied torque values of aged wrenches. MATERIALS AND METHODS: Five new and aged wrenches that had been used approximately 250 times in a 1-year period were tested. The torque applied by friction- and spring-style wrenches was measured with a specially designed strain gauge indicator. Descriptive statistics, the one-sample t-test, and the independent-samples t-test were used to analyze values obtained from all torque wrenches. RESULTS: The accuracy of new and aged torque devices of all brands except Bredent differed significantly from the target values, but the mean values for aged and new wrenches did not differ significantly from each other (p > 0.05). Values for the spring- and friction-type torque wrenches deviated from the target values by 11.6% and 10.2%, respectively. CONCLUSION: The accuracy of aged torque wrenches is adequate for prosthetic screw tightening, but that of new torque wrenches is unsatisfactory and must be examined carefully before delivery.


Subject(s)
Bone Screws/standards , Dental Implantation, Endosseous/instrumentation , Dental Implants/standards , Dental Stress Analysis , Humans , Stress, Mechanical , Torque
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