Labial Surface Research Articles

Aesthetic rehabilitation on fractured and altered passive eruption anterior teeth: A case report

Objective: This case report aims to present the management of crown fractures with pulpal exposure caused by traumatic injury and a condition called gummy smile or altered passive eruption (APE), through a multidisciplinary approach.
 Case Report: A 24-year-old male patient came to the Dental Conservation Clinic RSGM Prof Soedomo FKG UGM, complained of broken teeth and pain in the upper front tooth due to an accident. #12 and #21 experienced horizontal discontinuity to the dentine surface and some lines on the labial surface and #11 underwent a fracture with exposure of the pulpal tissue. The patient wants to take care of broken teeth and improve his smiles.
 Results: A treatment plan was formulated, which consisted of a stepwise treatment including endodontic treatment, crown lengthening, prefabricated glass-fiber post followed by a core build-up, and finally, direct composite to achieve patient satisfaction.
 Conclusion: The careful planning of a multidisciplinary approach such as endodontics, periodontics, and direct restorations can treat patients with complex aesthetic complaints relating to problems with the tooth and its soft tissues, and immediate restoration for providing a fast, predictable, economical, yet satisfactory result to improves patient self-confidence.

A Stereophotogrammetry Face Study Between Dentate and Edentulous Adults Rehabilitated with Either a Conventional Complete or an Implant-Supported Fixed Complete Denture.

Quantifying in edentulous patients the facial collapse and whether complete conventional denture (CCD) and implant-supported fixed complete denture (ISFCD) can restore the facial proportions to match those of a dentate patient (CG) is relevant for clinical dentists. One hundred and four participants were enrolled and divided into edentulous (n=56) and CG (n=48). The edentulous participants were rehabilitated with CCD (n=28) or ISFCD (n=28) in both arches. Anthropometric landmarks in the face were marked and captured by stereophotogrammetry. Linear, angular, and surface measurements were analyzed and compared among groups. The statistical analysis was performed by an independent t-test, the one-way ANOVA, and Tukey's test. The significance level was set at 0.05. The facial collapse was quantified as a significant shortening of the lower third of the face affecting facial aesthetics in all parameters evaluated and the same was observed in comparison among CCD, ISFCD, and CG. The CCD presented statistical differences with the CG group in the lower third of the face and labial surface, and the ISFCD showed no statistical differences with the CG and CCD. The facial collapse in edentulous patients could be restored through oral rehabilitation with an ISFCD similar to those of dentate patients.

Modified Processing Technique for Acrylic Resin Denture Base

Modified flasking technique for acrylic resin denture base at sandy stage. The uniform denture base plate wax pattern was made on the stone casts with a thickness of 3 mm. For the flow of acrylic on ridge, the necks of teeth were slight grinded from palatal or lingual surfaces toward buccal surface to allow more space. The volume of the definitive casts must be reduced as much as possiblebefore flasked in the lower part of the traditional flasks and fill with dental plaster (class II) covering the buccal, labial, incisal and occlusal surfaces of the teeth to give more support and prevent teeth migration. After curing cycle, the denture bases are carefully deflasked, the excess trimmed and polished the surfaces of the denture. Dentures processed with this procedure provides good retention and esthetic, more hygienic and comfortable for the patient than those processed with the conventional method. Giving more support and prevent teeth migration, comfortable for patient, good esthetic, give fine details of the mold and decreasing of time required for processing and finishing the cured prostheses.

The Effect of Dehydration on Tooth Color: A Prospective In Vivo Study.

Introduction The influence of dehydration on tooth shade constitutes a significant aspect, making it a pivotal area of study, particularly within the field of restorative dentistry. This prospective study was done to analyze, using a spectrophotometer, how dehydration affects the shade of the teeth. Materials and methods Twenty-five participants were recruited in this prospective study that took place in the Dental Care Center of Saint Joseph University of Beirut (Lebanon) between October 2022 and January 2023. The inclusion criteria for this study primarily comprised four intact maxillary incisors. On the other hand, damage, cavities, restorations, and staining served as exclusion criteria. The VITA Easyshade Advance (Vident,Brea,CA) spectrophotometer was used to record the measurements. The measures of L (which represents darkness to lightness), a (which represents greenness to redness), and b (which represents blueness to yellowness)were registered at the center of each tooth's labial surface at baseline and then at 10-minute intervals for 30 minutes while the teeth were dehydrating due to the placement of a rubber dam. The color difference (ΔE) was later calculated using L*a*b* measures, with the perceptibility threshold set at ΔE00=0.8. Statistical analyses were performed using the Friedman test, the Bonferroni post hoc test, and the Wilcoxon signed-rank test. Results The different color changes represented byΔE(ΔE1, ΔE2, and ΔE3) were found to be significantly higher than the perceptibility threshold of 0.8 (p<0.001). A statistically significant difference was found between ΔE1 and ΔE3 (p<0.05). Moreover, a statistically significant difference was found between L0, L10, L20, and L30 (p<0.001). Statistically significant differences (p<0.05) exist between the means of L0 and L20, the means of L0 and L30, the means of L10 and L20, and the means of L10 and L30. Conclusion This study showed that dehydration affected the shade of the teeth: Lightness increased, and therefore, the teeth appeared whiter. Dentists should consider the hydration status of the teeth when evaluating color for treatments, as dehydration can significantly affect shade matching: the more the dehydration time elapses, the more the color difference compared to the baseline increases.

Maternal factors associated with early childhood caries among 3–5-year-old children with low socio-economic status in Trishal, Bangladesh

IntroductionEarly Childhood Caries (ECC) is more prevalent in nations where a larger portion of the population resides below the poverty line. This study aimed to evaluate the connections between maternal awareness, attitudes, practices related to oral health, and the occurrence of ECC among children aged 3–5 years in Bangladesh, a low–middle income country with high level of poverty.MethodsThis cross–sectional study recruited mother–child pairs with a focus on children aged 3–5 years from low socioeconomic backgrounds in Trishal, Bangladesh. Data collected included maternal oral health knowledge, attitudes, and behaviors. Clinical examinations were conducted to check for dental plaque on the upper central incisors' labial surfaces. ECC was identified using the ICDAS II index criteria. Associations between maternal oral health knowledge, attitudes, behaviors, and children's plaque score and caries status were analyzed using multivariable logistic regression, and adjusting for confounding variables (child's age, gender, mother's age, education, and number of children).ResultsAmong 532 mother-child pairs, 491 (93.2%) mothers were unaware of the role of fluoride in preventing caries, while 516 (97%) recognized the importance of using fluoridated toothpaste during brushing. Additionally, 520 (97.7%) mothers reported not knowing how to brush their child's teeth, and 87 (16.4%) brushed their children's teeth twice daily. Visible dental plaque was observed in 420 (78.9%) children, and 321 (60.3%) had ECC. Higher plaque score increased the odds of ECC in the study population (AOR: 5.617, 95% CI: 3.511–8.987).ConclusionsMothers of preschool children with low socioeconomic status were poorly aware of caries preventive behaviors and had suboptimal oral health practices for their children. The plaque score was the only oral health factor that seems to increase the risk for ECC among children with low socio-economic status in Bangladesh. It is imperative to prioritize support and interventions aimed at improving oral hygiene practices to reduce ECC risk in this population.

An In-Vitro Analysis of the Surface Treatment of Orthodontic Bracket Bases With Er,Cr:YSGG Laser and Its Effect on Shear Bond Strength.

Introduction Shear bond strength is indispensable to prevent the debonding of orthodontic brackets. Lasers have been proven to alter the bond strength of orthodontic brackets, but their efficiency has not been validated in many trials. The study aimed to evaluate the impact of the Er,Cr:YSGG laser on the bases of orthodontic brackets and determine their bond strength with the enamel surface. Materials and methods The Waterlase iPlus (made in the USA in 2012), comprising an Er,Cr:YSGG laser, was used. Based on the surface treatment of brackets, two groups were assigned (n=10), comprising laser-treated and untreated bracket bases. The brackets were treated with the minimum laser intensity (50 Hz, 4.5 W). Then, the brackets of both groups were attached to the labial surfaces of previously extracted premolars, respectively. The shear bond strength of brackets (SBS) was assessed using the universal testing device, and the Adhesive Remnant Index (ARI) was also measured. An independent sample t-test was used to compare the bond strength between the laser-treated and untreated brackets. Results The mean bond strength of laser-treated and control group brackets was 5 MPa and 8.63 MPa, respectively. The laser-treated brackets showed lower bond strength than the control brackets, but the results were statistically insignificant (p=0.23). The ARI analysis stated that bond failures occurred mostly in the region of the bracket and adhesive interface. Conclusion Laser-etched bracket bases showed lesser shear bond strength than the untreated ones, though the difference was statistically insignificant.

The northernmost occurrence of non-karaurid salamanders (Lissamphibia, Caudata) in the Mesozoic

Isolated incompete salamander dentaries from the Lower Cretaceous Teete locality in Yakutia (Eastern Siberia, Russia) represent the northernmost occurrence of non-karaurid salamanders in the Mesozoic and are evidence that small-sized salamanders lived in high latitudes (paleolatitude estimate of N 62°–66.5°) in the Northern Hemisphere in the Early Cretaceous. These gracile and lightly built dentaries are characterized by the presence of numerous slender and closely spaced pedicellate teeth, a sharp ridge along the ventral edge of the postsymphyseal region, numerous neurovascular foramina that open into parallel longitudinal grooves on the labial surface, and a complex neurovascular system. The neurovascular system, which consists of a large longitudinal canal for the ramus mandibularis internus of the trigeminal nerve associated with smaller lateral canals and an entirely separate anterior part of the alveolar canal for the branches of the ramus alveolaris of the facial nerve, is similar to that of the long-lived Juro-Cretaceous small-sized non-karaurid salamanders of the genus Kiyatriton. The Teete faunal association “relic karaurid stem salamander—small-sized non-karaurid salamander” is characteristic for the “Great Siberian refugium” for Jurassic vertebrate relicts that covered the vast northeastern part of the Asiatic continent during the Early Cretaceous.

The exceptionally well-preserved Sauropleura scalaris (Nectridea: Urocordylidae) from the late Carboniferous of the Czech Republic: new information on ontogeny, lateral line and tail

Abstract Urocordylids represent a group of the late Carboniferous–early Permian basal tetrapods, with short limbs, extremely elongated bodies and a deep and distinctive tail and vertebral architecture, which is indicative of an aquatic habitat. However, the important morphological structures that would indicate their ecological preferences unambiguously (e.g. hyobranchial apparatus, lateral line sulci) remain unknown. Moreover, the high degree of skeletal ossification present in urocordylids contrasts with the common pattern seen in most other basal tetrapods known to inhabit aquatic environments. Here, we describe an exceptionally well-preserved skull, with an associated mandible and a partial postcranial skeleton, of Sauropleura scalaris from the locality of Nýřany, Czech Republic, based on high-resolution micro-computed tomography. The labial surface of the mandible shows the first evidence of the lateral line system in Urocordylidae, which consists of both small pits and elongated grooves, and unambiguously supports the aquatic ecology of the group. The juvenile stage of the specimen provides new information on ontogeny of sauropleurines. The partly ossified opisthotic bone indicates that, unlike development in most other early tetrapods, the otic capsules were among the first neurocranial elements to ossify in nectrideans. Finally, an almost complete caudal region suggests that tails were much longer in sauropleurines than previously assumed.

Efficacy of Resin-Modified Glass Ionomer Cement Varnish and Sodium Fluoride Varnish in The Prevention of White Spot Lesions During Fixed Orthodontic Treatment- A Split Mouth Study

Objective: Evaluating efficacy of Resin-Modified Glass Ionomer Varnish and Sodium Fluoride Varnish in prevention of White Spot Lesions (WSLs) during early fixed orthodontic treatment; comparing the incidence of white spot lesions in control teeth and experiment teeth. Methodology: Design: A Cross-sectional analytical split mouth study. Setting: Orthodontic Department of Sinhgad Dental College and Hospital. Participants: A sample size of 288 maxillary and mandibular anterior teeth (24 participants) with newly placed orthodontic brackets, allocated randomly into 4 subgroups, 2 experimental and 2 control. Interventions: For each experimental quadrant in each patient, respective varnishes were applied on the labial surfaces of anterior teeth. WSLs were recorded before and after 3 months by direct visual inspection following International Caries Detection Assessment System II Criteria. Results: There was significant difference between pre and post recordings of both the varnishes (p&lt;0.05). The control groups showed higher incidence of (WSLs) as compared to the experimental groups (p&lt;0.05). Conclusion: The result obtained from the study suggested that both Sodium Fluoride Varnish (Embrace) and RMGI Varnish (Clinpro XT) will help to prevent WSLs in orthodontic treatments. Study registration: Scientific advisory committee and institutional ethics committee.

The Effect of Blocker Application on Color Matching of Different Colored Composite Resin Systems.

To evaluate the effect of blocker on color matching of different shaded composite systems on natural teeth, 120 anterior teeth were divided into two groups as light and dark shades (n = 60). Round cavities (7 mm in diameter; 2 mm in depth) were prepared on labial surfaces of the teeth. They were restored using three types of resin composites: multi-shaded (Estelite Sigma Quick, Tokuyama Dental, Japan), single-shaded (Omnichroma, Tokuyama Dental, Japan) and group-shaded (Neo Spectra ST, Dentsply Sirona, Germany) (n = 20). Blocker (Omnichroma) was applied to half of the samples in each group (n = 10). Color matching of the restorations with the surrounding tissues were evaluated either by visual analysis or an instrumental method. The resin composites tested did not yield acceptable results instrumentally. Using blocker with single-shade resin composite on dark-colored teeth yielded a minimal change in color in 2 mm deep cavities in the visual evaluation by dentists. Similarly, applying blocker with group-shaded and multi-shaded resin composite on light-colored teeth caused minimal change in color of 2 mm deep cavities in the visual evaluation by dentists. As the application of blocker had no effect on the color matching of different shaded resin composites in the visual evaluations by all observers, except by dentists, blocker may be used as a dentin shade in 2 mm deep cavities of anterior teeth.

Evaluation of the Effect of Different Antioxidants on Resin Bond Strength to Enamel after Bleaching: An In Vitro Study.

To compare and evaluate the efficacy of 10% sodium ascorbate (SA) solution, 10% alpha-lipoic acid (ALA) solution, 10% propolis solutions (PLS), and 10% pomegranate peel extract (PPE) solution on the shear bond strength (SBS) between composite resin and bleached enamel after 60 minutes. Ninety extracted teeth were divided into 6 subgroups (n = 15) based on the antioxidant applied: Group I: Bleaching + application of 10% SA solution for 60 minutes. Group II: Bleaching + application of 10% ALA solution for 60 minutes. Group II: Bleaching + application of 10% PLS for 60 minutes. Group IV: Bleaching + application of 10% PPE solution for 60 min. Group V: Positive control (PC) bleaching without antioxidant application. Group VI: Negative control (NC) specimen neither subjected to bleaching nor application of an antioxidant solution. About 35% hydrogen peroxide (HP) was used for bleaching the labial surfaces in the groups considered. Labial surfaces were then bonded with composite using a customized cylindrical mold followed by storage in distilled water for 24 hours and shear bond strength was tested using universal testing machine. The mean shear bond strength values for groups I, II, III, IV, V, and VI are 5.04, 2.29, 5.02, 4.07, 1.42, and 9.08 respectively. The peak shear bond strength value is obtained for the negative control group; whereas the lowest mean SBS value is obtained for the positive control group. All herbal extracts used in the present study have demonstrated a reversal of reduced SBS between resin composite and bleached enamel surface. The reduction in bond strength of adhesive restorations was conventionally overcome by delaying the bonding procedure for a specified period resulting in prolonged treatment duration and multiple appointments. Sodium ascorbate is most commonly used but it is postulated to form a porous scaffold capable of harboring bacteria. Herbal antioxidants are gaining popularity in this regard as they are naturally derived, effective and affordable phytochemicals in addition to being viable alternatives against drug-resistant strains of microorganisms.

Inhibition of Silver Diamine Fluoride-induced Tooth Discoloration by Using Natural Antioxidant: In Vitro Study.

Silver diamine fluoride (SDF) is a well-known caries preventive aid capable of arresting carious lesions and preventing secondary caries formation. Despite having the caries prevention potential, the clinical use of SDF is limited due to the tooth discoloration caused by SDF. The objective of this study was to evaluate the efficiency of natural antioxidants to inhibit SDF-induced tooth discoloration. A total of 32 bovine teeth were polished to create a 6 mm circular window on the middle 1/3 (for enamel) or on the cervical 1/3 (for dentin) of the labial surface. Specimens were treated either with SDF alone or SDF followed by ascorbic acid (AA)/alpha lipoic acid (ALA)/7th generation bonding materials. The color parameters Lightness (L*), Chroma (C*), and Hue (H*) of the tooth window were measured at pretreatment, 1-hour, 1-week, and 1-month posttreatment using a digital color chromometer. Repeated measure ANOVA showed a significant tooth color alteration at 1-hour posttreatment. The L* and H* values dropped and C* value elevated significantly in 1-hour posttreatment measurement. All experimental groups showed significant tooth color alteration after treatment (p < 0.05) and were unable to reverse the discoloration even after 1-month period except the ALA group which did not show any significant (p > 0.05) color alteration compared with the pretreatment value. Within the limitation of the in vitro model and according to the results of this study, it can be concluded that ALA has the potential to prevent SDF-induced tooth discoloration; however, AA was unable to prevent the discoloration. SDF induces discoloration of enamel and dentin can be reversed by applying Alpha lipoic acid immediacy after SDF application.

Evaluation of the cleaning efficacy of a normal toothbrush and a manual U shaped toothbrush in children aged 8–10 years: A randomized crossover trial

ABSTRACT Background: Plaque removal rates are influenced by toothbrush design as well as brushing methods. Aim: The study aimed to determine the efficacy of a manual U-shaped toothbrush when compared to a regular toothbrush in removing dental plaque from teeth in children aged 8–10 years. Materials and Methods: Our research included 40, 8–10-year-old children. Stage I included days 0–7, while Stage II covered days 8–15. A disclosing agent was used to identify and score the dental plaque. During Stage I of the study, Group I was given a regular toothbrush, and Group II was given a U-shaped toothbrush. During Stage II of the study, the cross-over of interventions was carried out. Loe-Silness gingival index and Turesky modification of the Quigley-Hein index were measured on the 8th and 16th day. Unpaired t-test/independent samples t-test were performed for comparison between the groups. Results: The intergroup evaluation of plaque scores on various surfaces between the two groups revealed statistically significant differences (P = 0.05) between the mean plaque scores at stage I on the labial surface (P = 0.001) and the lingual surface (P = 0.002) between the two groups. Comparing gingival health scores of various surfaces between the two groups, mesial, labial, distal, and lingual surfaces revealed statistically significant differences (P = 0.05) at stage II and lingual surfaces at stage I and stage II, respectively. Conclusion: The experimental U-shape toothbrush significantly reduced the extent of plaque on the lingual surfaces and improved the gingival index scores, which helped improve gingival health and oral hygiene.

Accuracy of Indirect Veneer Mock-Up in Comparison to Diagnostic Wax-Up.

To evaluate the dimensional discrepancy between the diagnostic wax-up and the resulting mock-up. A maxillary model with misaligned teeth was scanned, and an initial cast was 3D printed. A total of 60 identical casts were 3D printed from the initial one after scanning. Based on a digital additive veneer wax-up on the six anterior teeth, 10 more casts were 3D printed. The specimens were allocated to seven groups (n = 10) as follows-group 1: transparent silicone matrix with a flowable light-cured composite resin; group 2: same as group 1 but with the addition of a prefabricated transparent tray; group 3: silicone impression putty (65 Shore A) and light-body silicone impression material with a dual-cured bisacryl resin; group 4: same as group 3 but without the light-body silicone; group 5: silicone laboratory putty (92 Shore A) with a dual-cured bisacryl resin; group 6: silicone laboratory putty (92 Shore A) with PMMA; group 7: wax-up casts (control). Scans from the mock-ups were coregistered, segmented, and superimposed with the scans from the wax-up. The difference between the mock-up and the wax-up was quantified by morphologic operations. Results were analyzed by Kruskal-Wallis test and Dunn post hoc test (P < .05). All mock-ups were larger than the wax-up. Significant differences were found for every labial surface third. The incisal third was the least accurate third while the middle third the most accurate. The most accurate were groups 2 and 5, and the largest discrepancy was observed in group 6. The analog mock-up differs dimensionally from the wax-up, regardless of the technique/materials used.

Impact of Various Remineralizing Agents on Artificial White Spot Lesion on Primary Teeth-A Comparative Study.

The aim of the current research was to assess the effectiveness of different remineralizing substances on artificial white spot lesions on deciduous teeth. 45 deciduous teeth without dental caries constituted the study group for this in vitro research. A 3 mm by 3 mm window of enamel was uncovered at the occluso-gingival midpoint of the coronal labial surface; an acid-resistant nail varnish was coated alongside the uncovered enamel surface of all specimens, employing vertical strokes. Demineralization was executed for the tenure of 72 hours at 37°C temperature in an incubator. The forty-five specimens, fifteen in each group, were assigned to the investigational groups plus a control group as: Group A: Control, Group B: Calcium sucrose phosphate (CaSP), Group C: Casein phosphopeptide-amorphous calcium phosphate-fluoride (CPP-ACPF). Microhardness tester was employed for testing the microhardness of the enamel surface using a Vickers diamond indenter laden with twenty-five milligrams for approximately ten seconds. Vickers hardness number (VHN) calculations for the microhardness were performed at baseline and on the fourteenth day. The CPP-ACPF group exhibited greater mean microhardness value at 236.14 ± 2.12, in pursuit by CaSP group with a score of 231.98 ± 3.16 and then the control group at 220.22 ± 5.08. An extremely statistically significant difference was seen amid the groups. The current research arrived at a conclusion that both the remineralizing substances were certainly efficient in handling early dental caries, and additionally, casein phosphopeptide-amorphous calcium phosphate-fluoride (CPP-ACPF) was found highly efficient as a remineralizing substance, in pursuit by calcium sucrose phosphate (CaSP).

SEM microscopic analysis of the labial tooth surfaces after the bleaching procedure done by Epic Biolase diode laser 940 nm

Dental bleaching is a common procedure, requested and accepted by patients with aesthetic requirements. The SEM images were taken at different degrees of magnification, always looking for cracks, porosities, or other changes at this level, which could be related to the sensitivity that appeared after such a procedure. The standard bleaching procedure was applied to the labial surface of the tooth. Biolase Laser white 20 bleaching putty was used, which contains 45% hydrogen peroxide and then activated with 940 nm laser light. The microscopic SEM images of the labial faces on which the 45% concentration hydrogen peroxide type bleaching gel was applied showed that they do not present any structural damage to the enamel.

Evaluating the comparative efficacy of Bioactive glass containing Toothpaste, Amine fluoride-containing toothpaste and CPP-ACPF on remineralization of Artificial Incipient Enamel Lesion

Objectives: The purpose of this in-vitro study was to evaluate the comparative efficacy of Bioactive glass containing toothpaste (BioMin) and Amine fluoride-containing toothpaste (Amflor), and CPP-ACPF (GC Tooth mousse plus) on remineralization of artificial incipient enamel lesion and evaluated using Vickers micro-hardness test. Materials and Methods: A total of fifty freshly extracted premolar teeth were collected and decoronated at 1mm below the CEJ. An adhesive tape of size 4x4 mm is placed on the labial surface of each specimen. Following this, the specimens were mounted in acrylic resin moulds such that only the adhesive tape was exposed, and on the removal of the tape, a window of 4x4 mm is created. Then the specimens were randomly divided into five groups, among which specimens of four groups were subjected to demineralization for four days at 370c using an incubator. Group A (sound enamel), Group B (BioMin), Group C (CPP-ACPF), Group D (Amflor), Group E (demineralized lesion). The specimens of groups B,C,D were subjected to pH cycling for 10 days. Following whichmicro-hardness,all the specimens were evaluated using Vickers Micro-hardnessTest. Statistical analysis: The analysis was done using One Way ANOVA and inter-group comparison was done using a post hoc test. Results: Results showed statistically significant differences (p&lt;0.001) between groups B,C,D, and group E. Among the interventional groups even though there was no significant difference, group B( BioMin) showed higher micro-hardness values when compared to group C (CPP-ACPF) and group D(Amf). Conclusion: Under the limitation of this study, it can be concluded that Bioactive glass-based toothpaste (BioMin) is a novel technology that can be used for the remineralization of early enamel caries.

All that glitters is not gold: X-ray fluorescence analysis of a fixed dental prosthesis from Colecção de Esqueletos Identificados Século XXI, Portugal (CEI/XXI)

Access to better health care anticipates that more medical devices can be found alongside skeletal remains. Those employed in oral rehabilitation, with available brands or batch/series, can prove useful in the identification process. A previous study in the Colecção de Esqueletos Identificados Século XXI described macroscopically the dental prostheses. An unusual case of a dental device with chromatic alterations demonstrated to require a more detailed analysis. The individual, a 53-year-old male, exhibited, at both arches, a fixed tooth-supported rehabilitation, with gold colouring classified initially as a gold-palladium alloy. Simultaneously, a green pigmentation deposit was observable in bone and prosthesis. This investigation aimed to verify the elemental composition of the dental prosthesis alloy. Elemental analysis was performed by X-ray fluorescence in two regions (labial surface of the prosthetic crown and the root surface of the lower right lateral incisor). Both the spectra and the qualitative results found higher levels of copper and aluminium, followed by nickel, iron, zinc, and manganese. No gold or palladium was detected. The most probable assumption is that a copper-aluminium alloy was used, as its elemental concentration corresponds to those measured in similar devices. Dental prostheses of copper-aluminium alloys have been made popular since the 1980s, particularly in the USA, Japan, and Eastern Europe. Apart from the biographical information, it was also known that the individual’s place of birth was an Eastern European country, which highlighted the usefulness of this type of information when dealing with missing people cases.

What is the Impact of Impression Techniques on the Marginal Adaptation of Metal-Ceramic Crowns Fabricated by Direct Metal Laser-Sintering

Introduction: Studies on Marginal adaptation of restorations fabricated by direct metal laser-sintering DMLS are limited. This study to evaluate the effect of two impression techniques on the marginal adaptation of metal ceramic crowns fabricated by DMLS. Materials and Methods: Twenty intact maxillary premolars extracted for orthodontics reasons were received metal-ceramic crowns. After preparation according to the preparation guidelines for metal-ceramic crowns, the teeth were divided into two groups according to impression techniques (n=10): (1) group A IOS impression, (2) group B conventional impression. Group A specimens were scanned using IOS (I 500, MEDIT, Korea). Whereas, a custom-made tray used to make putty-wash impression to the specimens of group B. Group B casts were scanned using extraoral scanner (Identica T300, META, Korea). The metal coping designs were transferred to a direct metal laser-sintering (MYSINT100, SISMA, Italy), and they were made from Co-Cr blocks. The marginal adaptation was measured at labial, palatal, misael, and distal surfaces using microscope (Olympus, Japan). Student’s paired t test was used to assess the marginal adaptation between the groups. The cutoff value for statistical significance was set at α = 0.05. Results: A statistically significant differences in marginal adaptation was found between the impression techniques for all evaluations (labial, palatal, misael, and distal) (P&lt;0.05). The lowest values were recorded with IOS impression in all surfaces. Conclusions: the marginal adaptation values of IOS impression exhibited an acceptable marginal fit of less than 120 μm

Labial and Palatal Pressure Changes in Extraction Cases Before and After Maxillary Incisor Retraction: A Quasi-Experimental Study.

To evaluate the changes in lip and tongue pressure before and after incisor retraction in patients undergoing orthodontic treatment with premolar extraction and incisor retraction. A Quasi-experimental study Place and Duration of the Study: Orthodontic Department at Dow University of Health Sciences, Pakistan, from January 2018 to November 2019. The study included 64 patients who were divided into two groups, (32 patients of class I and 32 patients of class II malocclusion). The lip and tongue pressures were recorded before and after incisor retraction with the help of Flexiforce sensor. The collected data were statistically analysed using the SPSS V-24 software. Shapiro-Wilk test was used to test the normality of data. The mean difference between lip and tongue pressure before and after incisor retraction was analyzed by Wilcoxon Signed Ranks Test. The difference in soft tissue pressures between class I and class II treatment groups was carried out using the Mann Whitney test. The mean pressure on the labial surface of incisors was significantly reduced after premolar extraction and incisor retraction (p ≤0.001). On the other hand tongue pressure on the palatal side of incisors was enhanced after incisor retraction (p=0.008) Comparing the differences between Angle's class I and class II malocclusion in mean pressure changes before and after incisor retraction revealed that the difference was not statistically significant on labial (p=0.58) or palatal side (p=0.28) of maxillary incisors. Reduced lip pressure and increased tongue pressure were observed after incisor retraction, whereas no significant change was seen in between the class I and class II cases. This signifies that orthodontic extraction affects the pressure changes on incisors and teeth do not remain in balance equilibrium at rest. Lip pressure, Tongue pressure, Orthodontic treatment, Flexiforce resistive sensor, Extraction, neutral zone.