Enamel Junction Research Articles

Comparative evaluation of peri-implant tissues in definitive and repeated abutment replacements: A randomized clinical trial.

Background:Repeated abutment replacements may insults the soft tissue (mucosal) barrier mechanically, that might initiate other toxic irritants and bacteria into the mucosal-implant barrier that may affect the strength of the tissues around implants. The development of the “definitive abutment,” might minimize the chances of peri-implant soft and hard tissue loss. Therefore, the study was designed to assess peri-implant tissue dimensions in dental implants with definitive abutment (Test group) and repeated abutment replacements (Control group).Materials and Methods:Twenty edentulous sites from systemically healthy participants were selected for the study. Parameters registered were bleeding on probing, Sulcus probing depth, peri-implant marginal bone loss (PMBL) and additionally, two parameters were measured both clinically and radiographically, which included distance of cement enamel junction to alveolar crest (CEJ-AC) and distance of CEJ to gingival margin (CEJ-GM). At the time of surgery, sites were allocated randomly to either test group or control group. All the measurements were recorded at baseline, 3 and 6 months.Results:The PMBL increased from baseline to 3 months in control (1.05 ± 0.28 mm) and test groups (0.65 ± 0.41 mm). When the clinical values of CEJ-AC and CEJ-GM were compared with their respective radiographic values, no substantial differences were noticed between both the groups. The soft-tissue margins in both the groups remained comparatively stable across all the time points.Conclusion:The findings of this study point toward the use of implants with definitive abutment are more beneficial in achieving better maintenance in terms of marginal peri-implant tissue health.

Sealing Ability of Various Types of Root Canal Sealers at Different Levels of Remaining Gutta Percha After Post Space Preparation at Two Time Intervals.

ABSTRACTObjective:This study evaluated the apical sealing ability of various types of sealers (Sure-Seal Root, AH Plus, and GuttaFlow2) at different levels of remaining gutta percha after post space preparation at two time intervals (1 day and 1 week after obturation).Materials and Methods:One hundred and two single canal mandibular premolars were decoronated at the cement–enamel junction and biomechanically prepared. Twelve samples served as negative and positive controls (n = 6). The remaining 90 samples were distributed into three groups (n = 30 each), based on the used sealer for obturation with gutta percha (Sure-Seal Root, AH Plus, GuttaFlow2). Each experimental group was divided into two subgroups (n = 15 each), subgroup I: post space prepared 1 day after obturation and subgroup II: post space prepared 1 week after obturation. For each subgroup, the post space was prepared to a length that remained 3, 4, or 5 mm of gutta percha apically for each of five samples. Then, the dye penetration technique was used to measure the apical microleakage. Data were analyzed using “ANOVA test” and “post hoc Duncan’s test.”Results:Sure-Seal Root sealer demonstrated the best apical seal compared with other tested sealers. Post space preparation 1 day after obturation exhibited less microleakage than the group with 1 week after obturation. Additionally, 5 mm of remaining gutta percha showed superior sealing value than 3 and 4 mm.Conclusion:Bioceramic (Sure-Seal) sealer is the material of choice to be used when post space preparation is required. Post space preparation was preferred to be done 1 day after obturation than 1 week after obturation. Superlative apical seal was obtained with a maximum length of remaining gutta percha.

Demineralization Inhibition by Two Calcium-releasing Restorative Materials.

To compare the ability of two calcium-releasing restorative materials to inhibit root dentin demineralization in an artificial caries model. Preparations were made at the cementum-enamel junction of extracted human molars (40, n=10/material) and restored with two calcium-releasing materials (Experimental composite, Pulpdent Corporation and Cention N, Ivoclar Vivadent), a resin composite (Filtek Supreme Ultra, 3M Oral Care), and a resin-modified glass ionomer (RMGI) (Fuji II LC, GC). All materials (other than the RMGI) were used with an adhesive (Scotchbond Universal Adhesive, 3M Oral Care) in the self-etch mode, which was light cured for 10 seconds. All restorative materials were light cured in 2-mm increments for 20 seconds and then finished with a polishing disc. Teeth were incubated (37°C) for 24 hours in water. An acid-resistant varnish was painted onto the teeth around the restoration, leaving a 2-mm border of uncovered tooth. A demineralization solution composed of 0.1 M lactic acid, 3 mM Ca3(PO4)2, 0.1% thymol, and NaOH (to adjust pH=4.5), and a remineralization solution composed of 1.5 mM Ca, 0.9 mM P, and 20 mM Tris(hydroxymethyl)-aminomethane (pH=7.0) were prepared. Specimens were placed in the demineralization solution for 4 hours, followed by the remineralization solution for 20 hours and cycled daily for 30 days. The specimens were embedded, sectioned into 100-μm sections, and the interface between the restorative material and root dentin was viewed with polarized light microscopy. A line was drawn parallel with the zone of demineralization for each tooth. The area of "inhibition" (defined as the area external to the line) or "wall lesion" (defined as the area internal to the line) was measured with image evaluation software. Areas of inhibition were measured as positive values, and areas of wall lesions were measured as negative areas. A one-way analysis of variance (ANOVA) found significant differences between materials for "inhibition/wall lesion" areas in root dentin (p<0.001). Tukey post hoc analysis ranked materials (μm2, mean ±SD): Fuji II LC (5412±2754) > Cention N (2768±1576) and experimental composite (1484±1585) > Filtek Supreme Ultra (-1119±1029). The experimental composite and Cention N materials (used with an adhesive) showed net areas of inhibition greater than a reference resin composite, albeit at a lower level than a reference RMGI material (used with no adhesive).

A software approach for identifying the effect of dental caries on dentin-enamel junction.

Dental decay is the most prevalent oral disease worldwide since more than 2.4 billion people suffer from caries of permanent teeth. Therefore, any details about its progression into the hard-dental tissues could contribute to unravelling the mechanisms underlying this process. We have analyzed dental tissue sections with and without caries in order to detect structure differences corelating them with clinical aspects observable from the tooth surface. Our working hypothesis was based on finding a link between the process of tertiary dentin laying (as a response to coronal caries) and the subsequent obliteration of dentin tubules. We have selected N=10 extracted teeth with/without coronal caries, resin-embedded and sectioned them. A specific software was used to digitally quantify the density of unobliterated dentin tubules reaching the dentin–enamel junction (DEJ), considering as positive threshold criteria the presence of the odontoblast process inside the analyzed tubule. This study showed the differences between the healthy and carious-affected hard-dental coronal tissues. More odontoblast processes reached the DEJ in unaffected teeth. Using specific software, we have quantified their density decrease near a lesion. We have studied the dynamics of the carious study and measured the consequent structural modifications of the dentin. In conclusion, there is a significant difference between the number of dentin tubules containing odontoblast processes that reach the DEJ in healthy/altered tissues. The tooth reacts not only by production of tertiary dentin to protect the pulp chamber, but also by obliteration of dentin tubules, thus reducing the number of odontoblast processes reaching the DEJ. This pilot study could serve as the starting point in developing a dedicated software that could deliver a personalized pattern for decay progression by analyzing one single tooth and extrapolate the result to all the patient’s remaining ones.

A machine learning approach to investigate the materials science of enamel aging

Understanding aging of tooth tissues is critical to the development of patient-centric oral healthcare. Yet, the traditional methods for analyzing the composition–structure–property relationships of hard tissues have limitations when considering aging and other factors. ObjectiveTo apply unsupervised machine learning tools to pursue an understanding of relationships between the composition and mechanical behavior of aging enamel. MethodsMolar teeth were collected from primary (age ≤ 8), young adult (24 ≤ age ≤ 46) and old adult (55 ≤ age) donors. The hardness and elastic modulus were quantified using nanoindentation as a function of distance from the Dentin Enamel Junction (DEJ) within the cervical, cuspal and inter-cuspal regions of the enamel crown. Similarly, a co-located analysis of the chemical composition and structure was performed using Raman spectroscopy. A Self-Organizing Maps (SOMs) algorithm was implemented to identify multi-dimensional composition–property relationships. ResultsThe hardness and elastic modulus are positively correlated to crystallinity and negatively correlated with carbonate substitution. Furthermore, the effects from fluoridation on the age-dependent properties of enamel is non-linear and depends on its location. The contributions of fluoridation to the enamel properties are different in the cervical and non-cervical regions and appear to be unique within primary and senior adult teeth. SignificanceBased on the findings, unsupervised learning methods can reveal complicated non-linear structure–property relationships in tooth tissues and help to understand the materials science of aging and its consequences.

An in-vitro comparative evaluation of microleakage between giomer, compomer, composite and resin-modified GIC

Introduction: The marginal ingress of oral fluids and bacteria between the tooth – restoration interface is termed as microleakage or marginal leakage. The ability to maintain an unfailing margin improves the durability of a restoration to a large extend. Aim: Aim of this study was to evaluate microleakage of a Giomer, Hybrid composite, Compomer and Resin Modified Glass Ionomer Cement (RMGIC) along the enamel and cemental margins of class V cavities. Materials and Methods: This in-vitro study was performed on 80 human maxillary and mandibular premolars which were extracted for orthodontic reasons. Class V cavities were prepared on the buccal surfaces of teeth centered on the Cemento Enamel Junction (CEJ). Teeth were divided into four groups of 20 each and restored with RMGIC, Giomer, Compomer and Hybrid composite and were subjected to thermocycling. Teeth were then immersed in 0.5% Methylene blue dye for 24 hours. They were sectioned longitudinally from the middle of cavity into mesial and distal parts. The sections were observed under stereomicroscope(SM) to evaluate microleakage at both enamel and cemental margins. Depth of dye penetration was measured using a scoring system. Statistical Analysis: The data was analysed using the one-way ANOVA (Analysis of variance) test. The result is considered statistically significant if the ‘p’ value obtained is Results: The microleakage values of Giomer, Compomer and Hybrid Composite do not differ significantly from each other at the enamel margins while the microleakage of RMGIC is significantly higher than the other three materials (p Conclusion: At the enamel margins, giomer, compomer and hybrid composite showed comparable microleakage values which were significantly lower than RMGIC. At the cemental margins, compomer and hybrid composite showed significantly lower microleakage values compared to giomer and RMGIC. All materials exhibited greater microleakage at the cemental margins than at the enamel margins.

Assessment of Microleakage under Stainless Steel Orthodontic Brackets Bonded with Various Adhesive Systems: An In Vitro Study

The aim of this study was to evaluate the extent of microleakage beneath stainless steel orthodontic brackets bonded with different adhesive systems. Freshly extracted 60 human premolar teeth from mandibular arch were included in this study. After sterilizing all teeth, they were stored in thymol solution of 1% for further preparation. Acrylic blocks were used to mount the teeth in a way their roots were totally implanted up to the cement enamel junction in acrylic with crown being visible. A 0.022 slot, stainless steel preadjusted edgewise premolar brackets were taken. Sixty premolars were categorized randomly into three groups (20 premolars in each group) as follows: group I: flowable composite, group II: Fuji Ortho LC, group III: Transbond XT. Later, all the samples were subjected to thermocycling and tested immediately and 24 hours after water storage. The samples were submerged for 24 hours in methylene blue solution (2%) at room temperature. A ×20 magnification stereomicroscope was used to examine all samples. The lowest microleakage (1.34 ± 0.20) was shown by Transbond XT restored teeth, followed by flowable composite group (1.79 ± 0.32) and Fuji Ortho LC group (2.98 ± 0.13). An analysis of variance showed statistically significant differences among various adhesive systems. A statistically significant difference (p <0.05) among groups I and II, and groups II and III adhesive materials was seen. This study demonstrated microleakage in all the examined adhesive groups but the lowest microleakage was found with Transbond XT group followed next by Filtek Z350 XT group and Fuji Ortho LC group. Due to microleakage, the bacteria and fluids present intraorally penetrate through the gaps along the enamel-adhesive boundary. This penetration results in significant esthetic and clinical complications. Such problems related to microleakage can be addressed with the use of an appropriate adhesive agent.

Prevalência de perda de inserção periodontal em adolescentes de 12 a 16 anos em uma escola pública de Porto Alegre

The aim of this study was to verify prevalence of loss of attachment in 12-16 years old adolescents of a public school in Porto Alegre. The prevalence of loss of attachment was determined by means of periodontal probing a mesial, distal, buccal and lingual surfaces of incisors and first permanent molars. A trainer examiner performed the examination with Williams periodontal probe, odontoscope are standard illumination. The level of attachmet was defined as thc distance in millimeters from the cementum-enamel junction to the most apically probable portion, close to thc bottom of the sulcus/pocket. For cach site, two measurements were performed, the distance from the gingival margin to the cementure enamel junction, and the distance from the gingival margin to the bottom of the sulcus pocket. The level of attachment for a site was calculated subtracting the first and the second or, in case of gingival recession, adding both. Loss of attachment was considered when this measure exceeded 2 mm in buccal-lingual surfaces and 3 mm in proximal surfaces. 3048 sites were examined, showing a prevalence of 4.82% of loss of attachment. From these, 36.77% bled on probing and 61.22% did not. The buccal surface was the one with the highest prevalence of loss of attachment.

Comparison of shear stress acting on the severely worn anterior canine restored with 2 different restorations

Aim: To compare fracture resistance of severely destructed mandibular canine under oblique loading restored with Richmond crown verses zirconia endocrown. Materials and method: 10 mandibular canine were endodontically treated and divided into 2 group of 5 each both the group were cut 2mm above the cement enamel junction one group received endo crown and second group received cast metal post and core, both the group were subjected shear force on UTM at cross head speed of 1 mm/min the results obtained were calculated in newton’s and statistical analysis was carried out. Results: Cast metal post and core (972.4±217.51N) showed better resistance to fracture than Richmond crown group (1180.6±168.87N).statistical analysis done using unpaired t test (P value =0.1818) which was which was statistically insignificant. Conclusion: endocrown showed better resistance to fracture from shear forces than cast metal post and core.

Novel Approach to Tooth Chemistry. Quantification of the Dental-Enamel Junction.

The dentin-enamel junction (DEJ) is known for its special role in teeth. Several techniques were applied for the investigation of the DEJ in human sound molar teeth. The electron (EPMA) and proton (PIXE) microprobes gave consistent indications about the variability of elemental concentrations on this boundary. The locally increased and oscillating concentrations of Mg and Na were observed in the junction, in the layer adhering to the enamel and covering roughly half of the DEJ width. The chemical results were compared with the optical profiles of the junction. Our chemical and optical results were next compared with the micromechanical results (hardness, elastic modulus, friction coefficient) available in the world literature. A strong correlation of both result sets was proven, which testifies to the self-affinity of the junction structures for different locations and even for different kinds of teeth and techniques applied for studies. Energetic changes in tooth strictly connected with crystallographic transformations were calculated, and the minimum energetic status was discovered for DEJ zone. Modeling of both walls of the DEJ from optical data was demonstrated. Comparing the DEJ in human teeth with the same structure found in dinosaur, shark, and alligator teeth evidences the universality of dentin enamel junction in animal world. The paper makes a contribution to better understanding the joining of the different hard tissues.

Histomorphologic and Gravimetric Changes of Teeth Exposed to High Temperature - &lt;i&gt;In vitro&lt;/i&gt; Study

Background: In forensic dentistry, odontologists have been particularly interested in the investigation of burnt human remains. The purpose of our research is to provide morphological, stereomicroscopic, histological, and gravimetric findings from the investigation of the effects of thermal processes on teeth.Teeth, being the hardest substance in the body, give valuable information for forensic analysis. Objective: Histomorphology and gravimetric changes in teeth exposed to different ranges of high temperatures. Methodology: Thirty-six mandibular premolar teeth extracted for therapeutic purpose were taken and exposed to the varying higher temperatures. Macroscopic, stereomicroscopic, histological analyses along with the dry weight estimation were recorded at each temperature gradient. Results: From a lower temperature to a higher temperature, the specific colour change of the tooth was yellowish-orange, metallic black bronze and chalky white. Stereo microscopically, we observed intact teeth at 100°C; the gradual formation of micro cracks, crown-enamel separations from the cervical margin, eggshell cracking at 500°C; and a completely shattered crown at 900°C. Decalcified sections show dilation in the dentinal tubular pattern at 300°C. Loss of typical architecture was noted at 400°C, with dentinal tubules exhibiting the vapor bubble appearance. In-ground section alterations on the scalloping nature of dentino enamel junction, coalescing radicular dentinal tubules and sand cracking appearance of the tooth were noted at 100°C, 300°C and 900°C, respectively. Significant reductions in the weight of the teeth samples were observed with higher temperatures. Conclusion: Incineration-induced morphologic, histologic, and gravimetric alterations may provide useful information regarding the temperature and duration of fire exposure. It might also assist in understanding the conditions of the fire.

English

Restoration of traumatic teeth with complicated crown root fracture poses many challenges to the clinicians. When the fracture line is below the level of gingiva, the prognosis of such fractured tooth is considered questionable or hopeless. Treating such cases is also challenging as they are associated with loss of ferrule and compromised biological width. Preservation of such diseased natural teeth usually involves a multi-disciplinary approach involving endodontic therapy, periodontal crown lengthening and / or orthodontic extrusion followed by prosthetic rehabilitation. Tooth injuries and complicated tooth fractures especially in the aesthetic region pose a great challenge to the clinician.1 When the fracture line extends at or below the level of cement enamel junction, the prognosis of such tooth is considered questionable or hopeless; they are usually associated with the loss of ferrule and compromised biological width, and therefore restoration of such teeth becomes a great challenge. To ensure functional longevity, endodontically treated teeth with less coronal structure must have at least 5 mm of tooth structure coronal to the crestal bone. Three milli meters of tooth structure is needed to maintain a healthy soft tissue complex, and 2 mm of coronal tooth structure incisal to the preparation finish line is necessary to ensure structural integrity.2 There are mainly two reasons why a tooth extraction should be avoided: Structural reasons and psychological stress associated with extraction. Psychological stress can be in the form of financial stresses associated with extraction and rehabilitation of the same and fear of post-traumatic pain. Extraction of tooth is also followed by aesthetic challenges as it may lead to hard and soft tissue resorption as the healing architecture is unpredictable. In this case report a simple yet effective treatment is presented for a 21-year-old female patient with a chief complaint of clinical tooth fracture in relation to 44. After thorough clinical and radiographic examination, it was decided to reinforce the use of flexible glass fibre post and incorporate the same as tags to engage E chain to facilitate orthodontic tooth extrusion followed by prosthetic rehabilitation. The purpose of this case report is to describe the use of a simple chair side technique for a tooth fractured at the level of cementoenamel junction (CEJ) with forced tooth eruption.

Quiste dentígero en odontología. Reporte de caso

El quiste dentígero es definido como una lesión quística que involucra la corona de un diente incluido que está relacionada con la unión amelocementaria. Clínicamente se manifiesta por un aumento del volumen asintomático, siendo generalmente descubierto en un examen radiográfico de rutina o por la investigación de un diente no erupcionado. Radiográficamente presenta una lesión radiolúcida unilocular asociada a un diente incluido. Este estudio presenta un caso clínico de un paciente con quiste dentígero en la región posterior de la mandíbula, tratado quirúrgicamente por medio de enucleación y exodoncia de los dientes involucrados. Paciente de género masculino, de 9 años de edad, que compareció a la Clínica de caso Odontología de la Universidad de Ribeirão Preto (UNAERP), Brasil, con queja de abultamiento inferior izquierdo de la cara y marcada asimetría facial, la radiografía panorámica y tomografía computarizada evidenciaron la presencia de un quiste dentígero extenso. Delante de este cuadro clínico y radiográfico, el plan de tratamiento establecido fue la enucleación del quiste para permitir la erupción de los dientes sucesores permanentes, seguido por la exodoncia de los elementos dentarios 74/75. El tratamiento quirúrgico se mostró rápido y resolutivo evidenciando que la elección del tratamiento debe ser cuidadosamente evaluado para cada caso.

The use of CBCT to asses buccal bone thickness overlying mandibular anterior teeth

Objectives: the aim of this study was to determine the relationship between gingival width with respect to the underlying bone thickness in mandibular anterior sextant.Material and metods: 40 CBCT were included. Buccal bone thickness was measured at 3, 4.5, 6, 8 mm apical to the cement–enamel junction (CEJ). In addition, the apicoincisal gingival width was measured.Results: at 3 mm from the cement-enamel junction, the buccal bone plate was in 69.4% of cases, the average thickness of buccal bone plate for all teeth was less than 1.0 mm, at the level of 4.5 and 6 mm in 30,6% of cases “Absence” of the external cortical plate, the thickness of which gradually increased in the apical direction (8 mm). When the efficiency is less than 2 mm, the effect of the absence of the external cortical plate according to CBCT data was more often observed.Conclusion: in this study revealed the relationship between the gingival width and the anatomical features of the buccal bone plate.

Comparison of adhesive bond strength among fiber reinforced post and core with different cementation techniques: In vitro study.

To investigate push-out bond strength (PBS) of fiber post to radicular dentin after using different cementation techniques. Sixty single-rooted premolars were disinfected and cleaned by mechanical instrumentation. S1, S2, and SX were used for canal shaping and finishing of the canal was carried out using F1 and F2. This was followed by constant irrigation and smear layer removal using 17%EDTA. The canal was dried filled with gutta-percha and canal space was prepared using a peso reamer. Based on cementation techniques, samples were randomly allocated into six groups. Group 1: One-step Monoblock MC; Group 2: One-step, Monoblock MC-NA (no adhesive) GFP; Group 3: One-step, RX-MC-Monoblock; Group 4: Two-step, RX-MC; Group 5: Two-step, RX-FZ; and Group 6: Two-step RX-FZ-custom post. All specimens were mounted in polyvinyl pipes using acrylic resin up to cement enamel junction. All specimens were mounted in a universal testing machine subjected to push-out forces at a speed of 0.5 mm/min. Five samples from each group were sputter-coated with 6 nm gold thickness for 300 s at 250 mA. The coated specimens were assessed under the scanning electron microscope (SEM). Analysis of variance (ANOVA) and Tukey Kramer multiple comparisons tests were performed to compare means among groups maintaining the level of significance at (p < 0.001). The highest PBS was displayed in RX-MC-Monoblock (199.020 ± 21.432 MPa). Whereas, lowest PBS was found in Monoblock MC-NA (no adhesive)-GFP (76.440 ± 9.468 MPa). Among one-step groups, RX-MC Monoblock exhibited the highest PBS (199.020 ± 21.432 MPa) comparable to one-step Monoblock MC (134.28 ± 19.37 MPa) (p > 0.05). Similarly, among two-steps groups, two-step RX-MC demonstrated significantly higher PBS values than two-step RX-FZ (143.340 ± 23.68 MPa) and RX-FZ-custom post (86.90 ± 7.41 MPa) (p < 0.05). One-step RX-MC-Monoblock technique using self-adhesive cement and core foundation composite resin material multicore flow when cured simultaneously exhibited the highest bond integrity of post retention compared to other cementation technique.

Gingival Biotype Classification, Assessment, and Clinical Importance: A Review

A normal scalloped gingival line at the cement enamel junction of the teeth forms one of the components of an aesthetic smile. Clinicians handle gingiva in several periodontal procedures and the resulting gingival architecture is not always ideal. In the era of aesthetic-driven dental therapy, it is important that a clinician should be well aware of all the prognostic factors that may affect the final aesthetic outcome of dental treatment. Gingival biotype is one of the important factors which influences indications and outcome of various periodontal, restoratives, surgical, and implant therapy. Thin gingival biotype responds differently than thick gingival biotype. Gingival biotype assessment before various dental-related procedures is mandatory now to achieve a predictable and stable gingival margin position. This review describes the various classifications, methods of assessment, and clinical importance of gingival biotype during dental treatment.

Novel Approach to Tooth Chemistry: Quantification of Human Enamel Apatite in Context for New Biomaterials and Nanomaterials Development.

A series of linear profiles of the elements of the enamel in human molar teeth were made with the use of an electron microprobe and a Raman microscope. It is postulated that the enamel can be treated as the superposition of variable “overbuilt” enamel on the stable “core” enamel at the macro-, micro- and nanoscale level. The excessive values characterize the “overbuilt enamel”. All the profiles of excessive parameters along the enamel thickness from the enamel surface to the dentin enamel junction (DEJ) can be approximated very precisely with the use of exponential functions, where Ca, P, Cl and F spatial profiles are decaying while Mg, Na, K and CO32− ones are growing distributions. The “overbuilt” apatite formed on the boundary with DEJ, enriched in Na, Mg, OH and carbonates, reacts continuously with Ca, Cl and F, passing into an acid-resistant form of the “overbuilt” enamel. The apparent phases arriving in boundary regions of the “overbuilt enamel” were proposed. Microdiffraction measurements reveal relative variation of energy levels during enamel transformations. Our investigations are the milestones for a further new class of biomaterial and nanomaterial development for biomedical applications.

Adhesive strength of bioactive resin for endodontic tooth build up to dentin treated with conventional and contemporary treatments.

The aim of present ex-vivo study was to assess and evaluate the influence of alternative dentinal conditioning methods- Er,Cr:YSGG (ECL) and Photodynamic therapy (PDT) in comparison to traditional etching regimes- Self Etch Resin (SER) and total etch and rinse (TER) on the bond values of Bioactive restorative material (BA) and Multicore (MC) bulk filled resin composite restorations. Eighty caries free mandibular molars were disinfected and embedded in acrylic resin up to Cemento enamel junction (CEJ). Buccal surfaces of all samples were grounded to depth of 2 mm. Specimens were divided into eight groups (n = 20) based on surface treatment received. Samples in group 1 and 2 conditioned with ECYL, group 3 and 4 pre-treated with methylene blue photosensitizer (MBP), group 5 and 6 surfaces conditioned with TER and samples in group 7 and 8 conditioned with SER. Dentin bonding agent was applied and samples of group 1, 3, 5 and 7 were bonded with BA and 2,4,6,8 bonded to MC. Samples were placed in universal testing machine for SBS testing. Data was assessed using analysis of variance (ANOVA) and Tukey multiple comparisons test. Specimens in group 6 treated with TER and bonded with MC demonstrated maximum SBS (19.61 ± 0.587 MPa). Whereas, group 3 dentin conditioned to MBP and bonded to BA displayed lowest bond values (12.01 ± 0.892 MPa). Samples in group 3 and group 4 dentin treated with MBP bonded to MC (13.68 ± 0.221 MPa) and BA (12.01 ± 0.892 MPa) displayed comparable bond integrity (p > 0.05) CONCLUSION: Dentin pre-treated with TER still remains the gold standard. ECYL as an alternative approach to condition dentin has shown potential and can be recommended in clinical settings. MC as bulk fill composite is recommended over BA irrespective of dentine conditioning technique. MBP as dentin conditioner needs further investigation.

Influence of disinfection of caries effected dentin with different concentration of silver diamine fluoride, curcumin and Er, Cr:YSGG on adhesive bond strength to resin composite.

The aim of the study was to determine the effect of various disinfectants (CP, MB, 3.8 % SDF, 38 % SDF and ECL) on caries affected dentine (CAD) and its bond strength to composite restoration MATERIAL AND METHODS: Fifty carious mandibular teeth were collected based on the criteria of ICDAS (International Caries Detection and Assessment system). Specimens up to cement enamel junction were fixed in poly vinyl pipes. All caries molars were grinded using silicon grinding carbon disk and randomly assigned into five groups based on disinfecting regimes (n = 10). Group 1, Caries affected dentin (CAD) treated with MBP [100 mg/L]; Group 2, CAD treated with Curcumin photosensitizer (CP) [500 mg/L]; Group 3, CAD treated with 3.8 % SDF Group 4, CAD treated with 38 % SDF and group 5 sterile with Er,Cr:YSGG (ECL).Self-etch adhesive bond was smeared over the surface of all specimens followed by application of composite incrementally and light cured. Samples were debonded in a universal testing machine and shear bond strength (SBS) was noted in MegaPascal (MPa). The debonded surfaces were evaluated under stereomicroscope to determine the failure mode. For inter group comparison analysis of variance (ANOVA). Tukey HSD was applied for multiple group comparison. The significance level was kept at p < 0.05 RESULTS: The maximum bond strength was observed in group 2 CAD disinfected with CP (17.57 ± 0.85 MPa). Whereas, minimum bond strength values were presented by group 3 CAD disinfected with 38 % SDF (11.14 ± 0.29 MPa). CAD treated with MBP (14.21 ± 0.22 MPa) was comparable to group 5 (p > 0.05). Similarly, group 2 was found to be comparable to group 4 CAD disinfected with 3.8 % SDF (16.22±0.53 MPa) (p > 0.05). 3.8 % SDF and PDT with CP have shown potential to be adopted for dentin disinfection treatment without adversely affecting bond strength of CAD to composite resin.

Assessment of outcome of root canal treatment performed on an incomplete fracture non vital permanent first molar

Tooth infraction is usually of three types 1) confined to enamel (craze lines) and usually do not require treatment 2) related to cuspal fracture that typically do not involve pulp 3) more centrally located that do involve the pulp. Vertical root fracture (VRF) are longitudinal fracture that originate in root of teeth in contrast to tooth infraction that originate in the crown. VRF occurs usually in endodontically treated teeth. This case report represent tooth infraction originating in the tooth crown on the distal marginal ridge and propagating into the pulp chamber and DEJ(dentino enamel junction). Root canal treatment was performed and in a 7 month follow up period, there was a remarkable improvement in the supporting periodontal structures with bone deposition/remodelling in the crestal and furcation area/region and patient was quite satisfied with the treatment outcome.