Search published articles


Showing 12 results for Sorption

B. Seraj , N. Hakoupian ,
Volume 13, Issue 2 (5-2000)
Abstract

A case involving the replantation of an avulsed incisor after long extra-oral period (8 days) is reported. After cleaning the root surface, the tooth was soaked in fluoride gel for 20 minutes and root canal therapy was performed extraorally. The tooth was stabilized by wire and composite for six weeks. The patient has been periodically recalled and the tooth monitored for 36 months after replantation. Only minor external surface resorption was observed in the periapical area on the rodiograph, which was taken immediately before removal of the splint and the rate of subsequent replacement resorption has been acceptable. It should be considered that and extended extraoral period is not an absolute contraindication to replantation. Teeth replanted after long extra- alveolar periods can function for a long period of time and thus postpone prosthetic treatment.


D. Goodarzipoor, Sh. Shahrabi Farahani , H. Vahedi Gashniani ,
Volume 17, Issue 2 (6-2004)
Abstract

Statement of Problem: One of the dental lesions which is mainly diagnosed by periapical radiography is apical root resorption Diagnosis of the presence and extension of this lesion can put some effects on its treatment plan and prognosis.

Purpose: The aim of the present study was to evaluate the efficacy of periapical radiography on apical root resorption diagnosis. Materials and Methods: In this experimental study, sixty extracted teeth were examined radiographic and histological regarding the presence and extension of apical root resorption. It should be noted that periapical radiographs were taken before extraction of all mentioned teeth. The results were analyzed by Fisher’s exact test.

Results: The results of this study showed significant differences between radiological and histological examinations (P=0.0003). Significant correlation between these two observations was seen only in 53.33% of cases comprising 23% of teeth with root resouption. Non-correlation was found in 46% of samples. Moreover, there was no significant difference in the prevalence of apical root resorption between maxillary and mandibular teeth (P=0.233). Sensitivity of periapical radiographs in apical root resorption diagnosis was determined 57.3%. Conclusion: According to the findings of the present study, it seems that periapical radiography technique does not possess desirable efficacy in diagnosis of apical root resorption and its limitation should be considered by clinicians.


S. Khedmat ,
Volume 18, Issue 1 (3-2005)
Abstract

The purpose of this article was reviewing the literature related to the mutual effects of endodontics and orthodontics on each other providing documented information that can be used by dentists in clinical practice. The effect of orthodontic treatment on the dental pulp and its role in root resorption, the influence of previous trauma to the tooth and endodontic treatment in orthodontic tooth movements and root resorption, recommendations regarding endodontic treatment during orthodontic tooth movement and the role of the orthodontic forces in provision and outcome of endodontic treatment are being discussed. The effect of the orthodontic tooth movement on the pulp is focused primarily on the neurovascular system which can cause degenerative and/or inflammatory responses in the dental pulp. Although, most of these changes are considered reversible, it seems that teeth with complete apical foramen and teeth subjected to previous insults, such as trauma, caries, restorations and periodontal diseases are more susceptible to pulpal irreversible changes. Teeth with root canal treatment that are well cleaned shaped, and three- dimensionally obturated, exhibit less propensity to apical root resorption during orthodontic tooth movement. This outcome depends on the absence of microleakage for bacterial ingress. A traumatized tooth can be moved orthodontically with minimal risk of resorption, provided that the pulp has not been severely injured (infection or necrosis). If there is evidence of pulpal demise, appropriate endodontic treatment is necessary prior to orthodontic treatment .If a previously traumatized tooth exhibits resorption, there is a greater chance that orthodontic tooth movement will enhance the resorptive process. If a tooth has been severely traumatized (intrusion, avulsion) there would be a greater incidence of resorption with tooth movement. It is recommended that teeth requiring root canal treatment during orthodontic movement be initially cleaned and shaped followed by the interim placement of calcium hydroxide. Final canal obturation with gutta-percha should be accomplished upon the completion of orthodontic treatment. Endodontically treated teeth can be moved orthodontically similar to teeth with vital pulps. In case of endodontic procedures like apexification, there may be no need to delay the orthodontic treatment.
H. Ravanmehr , Sm. Seyed Javadein ,
Volume 18, Issue 4 (1-2006)
Abstract

Background and Aim: External apical root resorption is a common iatrogenic consequence of orthodontic treatment. Much controversy exists in the literature about changes in root lengths at post treatment periods. Although many practitioners believe that resorption becomes stable after active treatment, quantitative data are scarce. The purpose of this study was to determine quantitative changes in root lengths of maxillary incisors during fixed orthodontic post treatment period, and to assess if it is influenced by gender and factors related to active treatment.

Materials and Methods: This was a case cross over study, performed on 80 patients (52 females and 28 males) aged between 13 and 22 years. At debonding stage and beginning of retention phase of fixed orthodontic treatment, Hawley type retainer was fabricated for maxillary arch. Periapical radiographs of maxillary incisors using standard parallel technique were obtained immediately after debonding, and 3 and 7 months later. Crown and root lengths of maxillary incisors were measured using computer program. Changes in root lengths were calculated considering correction factors. Also associations between some factors and the change in root lengths during post treatment periods were assessed. These included gender, type of treatment plan (non extraction/extraction), technique (standard edgewise/straight-wire edgewise) and duration of active treatment (less than 2 years/2 years and more). T-test and 4-way ANOVA were used for statistical analysis with P0.05 as the limit of significance.

Results: No significant relation was found between apical root resorption of maxillary central incisors and time elapsed after treatment. Significant relation was observed between apical root resorption of maxillary lateral incisors and the length of post treatment period. No significant relation was found between root length changes of maxillary incisors during post treatment period and gender, type of treatment plan, technique, and the length of active treatment period (P 0.05).

Conclusion: Considering the general process of root length reduction in maxillary lateral incisors during post treatment period, establishment of preventive measures is emphasized.


F. Golbidi , A. Taherian ,
Volume 19, Issue 1 (4-2006)
Abstract

Background and Aim: Water sorption and solubility are important properties of acrylic resins. Denture base acrylic resins have low solubility. This solubility results from the leaching out of unreacted monomer and water soluble additives into the oral fluids. The solubility of denture bases can cause oral soft tissue reactions. In addition, water absorbed into this material acts as a plasticizer and decreases the mechanical properties such as hardness, transverse strength, fatigue limit and also can change the color and dimensional stability. The aim of this study was to compare the water sorption and solubility of Acropars and Meliodent heat cure acrylic resins.

Materials and Methods: This experimental study was performed on the basis of ADA specification No.12 and ISO No.1567 and standards NO: 2571 of Institute of Standards & Industrial Research of Iran. Six disc form samples of each acrylic resin were prepared, with the dimension of 50×0.5 mm. After desiccating, the samples were kept in an oven for 24 hours and weighed. Then they were immersed in water, kept in oven for 7 days and weighed again. After this phase, the samples were carried to a dessicator, for 24 hours and kept in an oven for drying and were weighed for the third time. Data were analyzed with Mann Whitney and one sample t-test. P<0.05 was considered as the limit of significance.

Results: Water sorption mean values were 30.5±0.1 µg/mm3 or 0.76±0.01 mg/cm2 for Meliodent samples and 30.7±0.87 µg/mm3 or 0.77±0.009 mg/cm2 for Acropars samples. No significant difference was observed in water sorption of these two materials (P=0.9). Meliodent acrylic resin showed lower solubility (1.7±0.097 µg/mm3 or 0.042±0.001 mg/cm2) than Acropars acrylic resin (2.5±0.13 µg/mm3 or 0.062±0.001 mg/cm2) (P=0.002).

Conclusion: Acropars heat cure acrylic resin matched well with the requirements of the international standards for water sorption, but its solubility was not favorable. This problem is probably the result of high concentration of residual monomer, the amount and type of cross linking agents and plasticizers as well as the amount of water soluble additives in this material.


Sina Haghanifar, Valiollah Arash, Farhad Soboti, Nasim Jafari,
Volume 25, Issue 2 (4-2012)
Abstract

Background and Aims: Apical root resorption is an adverse side effect of fixed orthodontic treatment which cannot be repaired. The aim of this study was to use panoramic radiographs to compare the root resorption before and after the orthodontic treatment with standard edgewise .018 appliance.

Materials and Methods: The before and after treatment panoramic views of sixty-three patients needed fixed orthodontic treatment included 1520 teeth were categorized into 3 Grades (G0: without resorption, G1: mild resorption with blunt roots or ≤ 1/4 of root length, G2: moderate to severe resorption or > 1/4 to 1/2 of root length. Relationship between root resorption and sex and treatment duration was analyzed with Mann-whitney and  Spearman's correlation coefficient, respectively.

Results: The findings showed that 345 teeth were categorized as Grade 1.  Grade 2 of root resorption was not found in this study. The highest amount of root resorption was recorded for the mandibular lateral incisor. In both gender, the root resorption of the mandible was more than that of the maxilla. The males showed significantly higher rate of resorption than the females (P<0.05). Root resorption was not significantly related to the treatment duration and the side of the jaws (P>0.05).

Conclusion: The mandible and male patients showed higher amount of root resorption. In addition, root resorption was not related to the treatment duration and the side of the jaws.


Mohammad Ebrahimi Saravi, Yushiaho Refoa, Yunes Nazari Dashlibrun, Reza Sharifi,
Volume 26, Issue 4 (1-2014)
Abstract

  Background and Aims: Impacted third molar reduces the bone level in the distal aspect of second molar, and sometimes it can lead to root resorption of the adjacent tooth. The purpose of this study was to determine this resorption using panoramic and periapical radiographs.

  Materials and Methods: In this cross-sectional descriptive study 54 patient (28 men, 26 women) above 15 years old with the average of 22 years in Oral and Maxillofacial Department of Tehran University were studied. A periapical radiography from the third molar and a panoramic radiograph were taken from each patient (Because of their routine use and evaluation of accuracy of panoramic compared with periapical), and the magnitude of the root resorption for the second molar was determined by 2 observers and written in a questionnaire. Data were analyzed using Fisher test.

  Results: The prevalence of the root resorption of the second molar adjacent to the impacted third molar in the panoramic and the periapical radiographies, with respect to the limitation of the sample size were 46.3% and 31.5%, respectively, with 95% confidence(P>0.05). Most of these resorptions were in the cervical third of the second molar roots and in cases in which the third molars were mesially oriented or horizontal. There was also no significant difference between panoramic and periapical radiographs.

  Conclusion: Due to the increased risk of the resorption of the second molar adjacent to the third molar, extraction of the impacted third molars, especiall y mesially oriented or horizontal ones are recommended.


Kimia Negahdari, Maryam Sadat Tavanagar, Rafaat Bagheri,
Volume 30, Issue 4 (1-2018)
Abstract

Background and Aims: Microhardness, sorption, and solubility are useful predictors of a resin composite’s clinical success. This study aimed to evaluate the effect of 60 days of water storage on the microhardness, sorption, and solubility of 3 commercial nanohybrid resin composites.
Materials and Methods: Three nanohybrid composites were evaluated: GC Kalore (GC), Aura (SDI), and G-ænial Universal Flo Universal Flo (GC). Ten disc-shaped samples were prepared for each material. After baseline weight measurement, the specimens were stored in distilled water for a period of 60 days, and then in desiccators for another 60 days. Specimens were weighed at 24 hours, 7 and 60 days of water storage and desiccation. For the microhardness test, 24 were prepared for each material and divided into 6 groups based on storage media (dry and wet) and storage time (24 hours, 7 days, and 60 days). Specimens were tested by a digital Vickers microhardness tester after storage and data were analyzed using SPSS software.
Results: G-ænial Universal Flo Universal Flo showed the highest sorption and solubility and the lowest microhardness after 60 days of water storage. GC Kalore showed lower sorption and solubility compared to Aura. Also GC Kalore had higher microhardness than Aura after 60 days of storage in water, while Aura had higher microhardness in dry storage.
Conclusion: Composites with lower sorption and solubility showed higher microhardnss in wet conditions. Flowable composite resin showed the lowest microhardness and the highest sorption and solubility values. Therefore, the negative effect of water sorption and solubility on Surface microhardness should be considered in clinical decisions.

Dana Jafarpur, Rafaat Bagheri,
Volume 31, Issue 4 (1-2019)
Abstract

Background and Aims: Glass ionomer cements are among direct restorative materials which are used in an environment saturated with moisture. Therefore, having the ability to prevent water contamination is crucial. The aim of this study was to determine the water sorption and solubility of five glass ionomer restoratives with and without two nanofilled resin coating agents.
Materials and Methods: Five glass ionomer cements (Fuji BULK/GC, EQUIA Forte Fil/GC, Fuji II LC/GC, riva self cure/SDI, riva light cure/SDI) and two resin-based coating (G-COAT PLUS/GC and EQUIA Forte Coat/GC) were used in this study. Water sorption and solubility were measured in accordance with the ISO 4049's. For each material, 15 disc-shaped specimens were prepared using a polyethelyn mould. The specimens of each material were randomly divided into two groups: 10 coated and 5 uncoated. For the coated groups of each material, 5 specimens were coated with G-COAT PLUS, and 5 with EQUIA Forte Coat. Data were analyzed using SPSS software version 18 (SPSS Inc., Chicago, IL, USA). Two-way ANOVA was applied to investigate if there were any interactions between materials and coatings. One-way ANOVA was used to compare different variables between the materials, and post-hoc Tukey’s test was performed to show significant differences in subgroup comparisons.
Results: A significant interaction effect was obsevred between materials and coatings (P<0.05) using two-way ANOVA. The uncoated groups showed higher mean sorption and solubility values compared to the coated groups, and the groups coated by G-COAT PLUS showed less mean sorption and solubility values than that of EQUIA Forte Coat. In general, the lowest mean sorption and solubility values among glass ionomer cements belonged to Fuji BULK.
Conclusion: The water sorption and solubility values of glass ionomer cements could be reduced by the use of a protective coating.

Parvin Alami, Behnam Bolhari, Soheil Niavarzy, Maryam Rezazadeh Sefideh,
Volume 32, Issue 2 (10-2019)
Abstract


Management of internal root resorption is a challenge to the endodontists. If it is left untreated, it may lead to the destruction of the surrounding dental hard tissues. Despite, routine obturation techniques are often employed without considering the best technique to solve this problem. This study presented a case of internal root resorption and apical periodontitis affecting tooth 12 (FDI) in a 31-year-old female patient, with a history of crown preparation in that region. We managed it with EndosealMTA and gutta-percha. After 12 months follow up, the tooth was still symptomless and in function and healing of bone resorption occurred.

Amineh Ghaznavy, Ahmad Reza Talaeipour, Mehdi Vatanpour, Amir Abbas Moshari,
Volume 33, Issue 4 (1-2021)
Abstract

Background and Aims: Pulpal exposures originated from the external cervical root resorptions have major effects on the treatment and prognosis. Therefore, the aim of this study was performed to compare the two different imaging systems-digital radiography with PSP (Photostimulable Phosphor) sensor in three horizontal different views and CBCT (cone beam computed tomography) images to assess the pulpal exposure in simulated cavity of external cervical root resorptions that was performed in 1398 in the School of Dentistry of Azad University.
Materials and Methods: 40 intact maxilla anterior teeth with straight roots were included. Teeth were randomly divided to two groups (20 teeth with and 20 without pulpal exposures). Each sample was assessed using PSP digital radiography (in 3 horizontal angles) and CBCT image system, to detect the presence of pulpal exposures. False negative and false positive results in 2 imaging procedures were judged with ratio test.
Results: The results showed in CBCT (P.P.V=85.7%) and (N.P.V=89.5%), and in digital intraoral radiography (P.P.V=80%) and (N.P.V=80%) in proximal defects. Ratio test showed that there were no significant differences in the proximal defects (P<0.4).
Conclusion: The results showed that there were no significant differences in detection of exposure in the proximal surfaces between two imaging systems.

Marzie Mazhari, Ali Habibikia, Ali Badfar, Mehdi Sabaghian, Arash Dabbaghi, Fattaneh Ghorbani Javadpour,
Volume 35, Issue 0 (5-2022)
Abstract

Background and Aims: By using the image processing capability in Cone-Beam Computed Tomography (CBCT), obtained information can be improved. The aim of the present study was to investigate the effect of sharpen image processing filter in determining the external resorption of the root apical region in single-rooted teeth due to the proximity of the impacted tooth using CBCT.
Materials and Methods: In this laboratory study, the lateral surfaces of the apical region of the root of 40 healthy extracted teeth were artificially cut by bur and the teeth were randomly divided into four groups: control, low, moderate, and high resorption. After preparing CBCT of the teeth, the samples were then processed with and without an image sharpening processing filter and examined by two observers. The results of this study were analyzed by SPSS22 and Medcalc Statistical Software version 14. The significance level was considered P≤0.05 for all the statistical tests.
Results: Specificity (100%) and sensitivity (66%>) were either complete or very high for both modes without and with the sharpen filter. The overall accuracy (0.83>) was high in both cases and no significant difference was observed between the two overall accuracies (P>0.05). Statistical analysis of both image observations by two observers showed that the overall sensitivity and accuracy in the medium and high resorption groups was much higher than the low resorption group, but the specificity in all groups was 100%.
Conclusion: The results showed that the images with a sharpening filter did not increase the detection power compared to the unfiltered images. However, as no loss of accuracy was observed with this filter, it could be used as a processing filter.


Page 1 from 1     

© 2024 , Tehran University of Medical Sciences, CC BY-NC 4.0

Designed & Developed by: Yektaweb