scholarly journals In vitro Study on the Dimensional Stability of Interocclusal Recording Materials

2017 ◽  
Vol 54 (3) ◽  
pp. 557-564
Author(s):  
Diana Cerghizan ◽  
Kamel Earar ◽  
Mihaela Monica Scutariu ◽  
Alina Ramona Dimofte ◽  
Gina Paunita Grecu ◽  
...  
Keyword(s):  
Dimensional Stability ◽  
In Vitro Study ◽  
Dental Arch ◽  
Continuous Increase ◽  
Recording Material ◽  
Standard Value ◽  
Materials Used ◽  
Dental Apparatus ◽  
Functional Position

The teeth are found in the alveolar processes of both the upper and lower jaw and they form the two maxillary and mandibular dental arches, the various relations of which support the performance of the dental apparatus functions, one of the most important of which is mastication. These relations are also known as interocclusal relations, among which the moments in which the dento-dental contacts (occlusal relations) play an important role. Maximum intercuspation (MI) is the most frequent mandibulo-cranial functional position with dento-dental contact. The vast majority of functional food incision and mastication cycles end in MI. The highest number of dento-dental contacts, and the largest possible stability and surface of these contacts are also achieved in MI. Given the relative easiness of determination, recording and transfer of the MI position, it is used in many clinical situations to report the models of the two arches. The interocclusal recording materials used in our study were seven silicones, six of which with addition reaction, five with special destination for interocclusal relation determination and a putty-like silicone normally used for dental arch impression - Elite HD and one condensation silicone used for impressions. The reason for choosing the last two materials was the fact that some practitioners frequently use putty-like impression silicone to determine interocclusal relations. According to the findings of the measurements shown in table 1, further to the initial impression process, at the time T0, satisfactory results were obtained both for addition silicones and for condensation silicones, Registrado X-tra being the only recording material which exhibited major deviation from the standard dimension (3 mm). As for the Optosil condensation silicone, we noted a significant increase of the thickness of the material starting with the first hour after impression and reaching considerable values on the 5th day, which were 0.3 mm higher than the standard value. Rigid addition silicones have the lowest dimensional stability; putty-like silicones are frequently used to record interocclusal relations for fixed prosthetics, which is wrong since they grow rapidly and this impedes on the space between the treated tooth and the opposite tooth, the result being a high restoration, which may determine premature contacts. Except for Optosil, which exhibited a continuous increase, most materials may be used to mount models in the simulator after 24 h.

scholarly journals Shear Bond Strength of Different Adhesive Materials used for Bonding Orthodontic Brackets : A Comparative in vitro Study

2015 ◽  
Vol 5 (1) ◽  
pp. 22-26
Author(s):  
Muzin Shahi Shaik ◽  
Snigdha Pattanaik ◽  
Sudhakar Pathuri ◽  
Arunachalam Sivakumar
Keyword(s):  
Bond Strength ◽  
Treatment Duration ◽  
Shear Bond Strength ◽  
Testing Machine ◽  
Test Group ◽  
In Vitro Study ◽  
Universal Testing ◽  
Materials Used ◽  
Adhesive Materials

Introduction: Bond strength is an important property and determines the amount of force delivered and treatment duration in orthodontics. Many light-cured bonding materials are being used; but it is required to determine the most efficient one withdesired bond strength. Objective: To determine and compare the shear bond strength of three visible light-cured composites (Transbond XT, Heliositand Enlight) and two self-cured composites (Rely-a-bond and Concise). Materials & Method: 100 extracted premolars were collected and randomly divided into 5 test groups of different adhesives. Brackets were bonded to the teeth in each test group with the respective adhesive according to the manufacturer’s instructions. Each specimen was debonded using Universal Testing Machine and the shear bond strength for each specimen was calculated. All the groups were compared by ANOVA one-way test. Results: There were statistically significant differences among the five groups (P<0.05). The shear bond strength of Enlight (13.92 ± 3.92) is similar to Transbond XT (14.30 ± 4.35). Conclusion: Light cure composites showed higher bond strength than self cure composites.

scholarly journals Hydroxyl and calcium ions diffusion from endodontic materials through roots of primary teeth - in vitro study

2005 ◽  
Vol 13 (2) ◽  
pp. 187-192 ◽  
Author(s):  
Ana Cristina Gerent Petry Nunes ◽  
Maria José de Carvalho Rocha
Keyword(s):  
In Vitro Study ◽  
Deciduous Teeth ◽  
Control Group ◽  
Apical Surface ◽  
Working Length ◽  
Group A ◽  
Periapical Healing ◽  
Materials Used ◽  
Spectrometer Data

The purpose of this research was to evaluate the diffusion of calcium (Ca+2) and hydroxyl (OH-) ions from materials with a calcium hydroxide base - Ca(OH)2 through the intact roots of deciduous teeth. This diffusion of ions is important for periapical healing. Forty-six deciduous teeth were selected and instrumented to their working length with #40 files. The teeth were washed during cleaning and shaping with a 1% sodium hypochlorite (NaOCl) solution. The canals were dried with paper points. The teeth were divided into 4 groups based on the sealer type, with 10 specimens in each group. A fifth group of 6 teeth without sealer constituted the control group. The materials used as sealers were: Ca(OH)2 paste associated to propylene glycol (CaPE) thickened at the proportion of 2:1 w/v; UFSC (Federal University of Santa Catarina) paste - a mixture of 0.3g of zinc oxide with 0.3g of Ca(OH)2 with 0.2ml of olive oil 1:1 w/w; Vitapex® and Sealapex®. The coronal access was sealed with a glass ionomer after the root had been filled with each sealer. A one-third apical surface and foramen was hard-pressed with Araldite®. The teeth were stored individually in flasks containing saline solution at 37ºC and 100% humidity. The OH- and Ca+2 ions diffusion levels were determined using a pH meter and an atomic absorption spectrometer. Data were collected at 48 hours and at intervals of 7, 30, 45 and 60 days. Statistical analysis was performed using ANOVA to compare groups. In the pH evaluation, the CaPE group presented the largest OH- ions diffusion, which peaked at sixty days (p=0.0309), when compared to the other groups (p<0.0001). In relation to amount of Ca+2 ions released, the CaPE paste showed the best results, followed by the UFSC's paste. These results suggest that the CaPE paste was the material that allowed the highest diffusion of OH- and Ca+2 ions.

scholarly journals Evaluation of Sealing Materials Adhesion to Enamel An in vitro study

2017 ◽  
Vol 54 (1) ◽  
pp. 129-132
Author(s):  
Andreea Simona Pop ◽  
Radu Septimiu Campian ◽  
Mariana Pacurar ◽  
Elina Teodorescu ◽  
Olimpia Bunta ◽  
...  
Keyword(s):  
In Vitro Study ◽  
Specific Method ◽  
High Concentration ◽  
Posterior Teeth ◽  
Inorganic Particles ◽  
Material Homogeneity ◽  
Materials Used ◽  
High Degree ◽  
Pits And Fissures

Sealing the pits and fissures of posterior teeth represents a local and specific method of caries prevention. The aim of this study was to evaluate the adhesion of two materials used in sealing pits and fissures: Pitt and Fisure and Fissurit FX (Voco), with the help of the scanning electronic microscope (SEM). The results of the study revealed a much higher quality of the Fissurit FX (Voco) product both in terms of adhesion to the enamel and material homogeneity. The Pitt and Fisure product showed a high degree of detachment from the enamel, marginal infiltration, large particles and a high concentration of inorganic particles.

scholarly journals Photoelastic analysis of stress generated by Connecticut Intrusion Arch (CIA)

2017 ◽  
Vol 22 (1) ◽  
pp. 57-64 ◽  
Author(s):  
Alessandro Schwertner ◽  
Renato Rodrigues de Almeida ◽  
Alcides Gonini Jr ◽  
Marcio Rodrigues de Almeida
Keyword(s):  
Descriptive Analysis ◽  
Reference Value ◽  
In Vitro Study ◽  
Distal Region ◽  
Dental Arch ◽  
Apical Region ◽  
Anterior Teeth ◽  
Distal Surface ◽  
Group 2

ABSTRACT Objective: The present in vitro study evaluated, by means of the photoelastic technique, the effects generated by the Connecticut Intrusion Arch (CIA), with a 90o bend on the distal surface of molar tubes and using the 4 x 2 appliance on the anterior and posterior regions of the upper dental arch. Methods: Five models were manufactured, in which two different clinical situations were correlated: 1) use of intrusion arch not cinched back and transpalatal bar for anchorage (Group 1); 2) use of intrusion arch cinched back and transpalatal bar for anchorage (Group 2). Stress generated in the apical and middle regions of tooth roots of maxillary anterior teeth and maxillary first molars was evaluated. Results: Taking a reference value of 1.0 MPa = 100%, qualitative descriptive analysis was performed, which showed uniformity between stress values in the apical region of anterior teeth of both groups (G1 and G2). In the posterior region, for models with the arch cinched back (G2), stress remained within 100%. As for G1 models (with the arch not cinched back), variations in the mesial surface of first molars were observed, with an increase of 20% in the generated stress. The apical region did not undergo any changes, while in the distal region of molars there was a decrease of 20% in stress. Conclusion: Laboratory results revealed differences in stress between Groups 1 and 2 in the molar region, thereby indicating that there was a tendency towards mesial root tipping of first molars when the distal end of the CIA was not cinched back.

Flexural strength and surface microhardness of materials used for temporary dental disocclusion submitted to thermal cycling: An in vitro study

2020 ◽  
Vol 18 (3) ◽  
pp. 519-527
Author(s):  
Tamires Borges de Lima ◽  
José Guilherme Neves ◽  
Ana Paula Terossi de Godoi ◽  
Ana Rosa Costa ◽  
Viviane Veroni Degan ◽  
...  
Keyword(s):  
Flexural Strength ◽  
Thermal Cycling ◽  
In Vitro Study ◽  
Vitro Study ◽  
Surface Microhardness ◽  
Materials Used

scholarly journals Linear Accuracy of Full-Arch Digital Models Using Four Different Scanning Methods: An In Vitro Study Using a Coordinate Measuring Machine

2020 ◽  
Vol 10 (8) ◽  
pp. 2741 ◽  
Author(s):  
Young Hyun Kim ◽  
Sang-Sun Han ◽  
Yoon Joo Choi ◽  
Chang-Woo Woo
Keyword(s):  
Coordinate Measuring Machine ◽  
In Vitro Study ◽  
Dental Arch ◽  
Accuracy Evaluation ◽  
Arch Model ◽  
Linear Measurements ◽  
Scanning Method ◽  
True Model ◽  
Measuring Machine

Improving the accuracy of the digital model is essential for the digitalization of the dental field. This study introduced a novel method of objective accuracy evaluation of digitized full dental arch model using coordinate measuring machine (CMM). To obtain a true linear measurement value using the CMM, 17 reference balls were attached to the typodont, and 12 measurements between balls on the X-(width), Y-(length), and Z-axes (height) were performed automatically. A rubber impression and a plaster cast replica of the typodont with balls were fabricated, and they were digitized with following methods: (a) true model intraoral scans; (b) impression cone-beam computed tomography (CBCT) scans; (c) cast CBCT scans; and (d) cast extraoral scans. Each scanning method was performed 20 times. Twelve linear measurements on the digitized models were automatically made using software. The one-sample t-test and one-way analysis of variance were used for measurement accuracy analysis. The cast extraoral scan was most accurate on X- and Y-axes, while impression CBCT was the most accurate on Z-axis. Over all axes, the intraoral scan resulted in the most deviation from the true model, and the reproducibility of each scan was also low. Extraoral scan shows high precision on width and length, and impression CBCT is advantageous for dental work where height factor is of importance.

Evaluation and comparison of dimensional stability of four interocclusal recording materials commonly available in India-An In-Vitro Study

2018 ◽  
Vol 9 (2) ◽  
pp. 6
Author(s):  
Jayaprakash Mugur Basavanna ◽  
Gurpreet Kaur ◽  
Ravikanth H Jujare ◽  
Rana K Varghese
Keyword(s):  
Dimensional Stability ◽  
In Vitro Study ◽  
Vitro Study

scholarly journals Evaluation of Dissolving Effect of Chloroform on Three Root Canal Sealers: An In Vitro Study

2017 ◽  
Vol 1 ◽  
Author(s):  
Azah Binti Zainal Abidin ◽  
Azmiera Binti A. Rahman ◽  
Kyaw Mya Htun ◽  
Tin Maw
Keyword(s):  
Stainless Steel ◽  
Root Canal ◽  
In Vitro Study ◽  
Root Canal Sealer ◽  
Original Weight ◽  
Bonferroni Test ◽  
The Difference ◽  
Materials Used ◽  
Endodontic Sealers

<p class="AbstractContent"><strong>Objective</strong>: The purpose of this study was to evaluate and compare the dissolving effect of chloroform on AH 26 (resin-based root canal sealer), Endofill (zinc oxide eugenol-based root canal sealer) and Sealapax (calcium hydroxide-based root canal sealer). Many previous literatures have compared the solubility of several solvents towards gutta percha but very few on endodontic sealers.</p><p class="AbstractContent"><strong>Methods</strong>: The materials used in this experiment apart from the three endodontic sealers are 30 standardized stainless-steel rings, microscopic glass slide, chloroform, acetone, and three decimal digital weighing scales. Thirty standardized stainless steel rings 8mm in diameter and 3mm in height were used for the preparation of sealer specimens and were randomly divided into three experimental groups of ten rings each. Each sealer was then mixed in accordance with the manufacturer’s instructions and introduced into the stainless-steel rings and was weighed to obtain the initial weight. Each sealer was weighed again after immersion in chloroform. The amount of sealer lost was the difference between this measurement and the original weight of the sealer. The results were tabulated and analyzed using analysis of variance (ANOVA).</p><p class="AbstractContent"><strong>Results</strong>: The ANOVA test showed that there were significant differences existed between the groups. The post-hoc (Bonferroni) test showed that AH26 had significantly greater dissolution than Sealapex. However, there were no significant differences in dissolution between AH26 vs. Endofill and Sealapex vs. Endofill.</p><p class="AbstractContent"><strong>Conclusion:</strong> According to the methodology proposed and based on the results of this study, it may be concluded that AH26 presented the highest dissolution value.</p>

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