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PurposeTo evaluate the effectiveness of the prosthetic rehabilitation, as well as the quality of life (QOL) of older edentulous maxillectomy patients.MethodsEffectiveness of the complete denture obturator prosthesis and QOL of 44 older patients who had resection of the maxilla and were restored with a definitive prosthesis that was in use for minimum 1 year was assessed using 3 instruments: European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Core Questionnaire (QLQ-C30), Head and Neck Cancer Module (QLQ-HN35), and Obturator Functioning Scale (OFS). Data analysis was performed by the one-way ANOVA on ranks, Spearman rank order correlation, and hierarchical multivariable rank regression at α=.05 level of significance.ResultsParticipants’ gender (PP =.016), surgical approach (P =.017), size of the maxillary defect (P=.028), participants’ prosthetic history (P =.047), and dental status of the mandible (P =.038) were significantly related to the self-reported effectiveness of the obturator. Perceived functioning of the complete denture obturator prosthesis (P=.001), participants’ gender (P=.002), the American Society of Anesthesiologists (ASA) physical status (P=.027), and surgical approach (P=.039) were significant predictors of QOL. ConclusionRestoration of the edentulous maxillectomy defect is challenging. An effective definitive complete denture obturator appeared to be the strongest predictor for advanced quality of life in older maxillectomy patients. The physical status of the older participants significantly affected the overall QOL, but did not influence the self-reported functioning of the complete denture obturator prosthesis.

Purpose The immediate application of a dentin-bonding agent after tooth preparation and before impression-taking (immediate dentin sealing [IDS]) has been suggested to provide several advantages concerning bacterial microleakage, hypersensitivity, and bonding quality. We reviewed the literature and clarified certain aspects related to each step of IDS application. Materials and Methods The search strategy comprised an electronic research in MEDLINE, Cochrane, Ovid and Scopus for studies published from January 1990 to December 2020 regarding the IDS technique and including both in vitro and clinical studies. Results After exclusion of irrelevant or duplicate articles, 88 articles focusing on aspects of the IDS technique were assessed. IDS seems to be advantageous with regard to bond strength, gap formation, bacterial microleakage, and dentin hypersensitivity. However, issues arising from interaction with impression materials, the provisional phase, and conditioning methods before cementation require further investigation. Conclusion There are no documented reasons preventing clinicians applying IDS in their everyday practice. On the contrary, the presented technique seems to be beneficial in certain aspects regarding indirect restorations.

Aim The aim of this literature review is to determine whether endocrowns are a reliable alternative for endodontically treated teeth with extensive loss of tooth structure, the indications and contraindications of this restorative choice, the principles that should be followed for tooth preparation and which material is most appropriate for endocrown fabrication. Background Rehabilitation of endodontically treated teeth with severe coronal destruction has always been a challenge for the dental clinician. Until recently, the fabrication of a metal-ceramic or all-ceramic full-coverage crown along with a metal or glass fiber post has been the "gold standard" proving its efficacy via numerous clinical studies. With the development of CAD/CAM technology and the evolution of dental materials, new minimally invasive techniques have been introduced with less need for adjustments and less incorporation of structural defects. One of them, the "monoblock technique," proposed by Pissis in 1995, was the forerunner of endocrown restoration, a term used by Bindl and Mormann to describe an all-ceramic crown anchored to the internal portion of the pulp chamber and on the cavity margins, thus obtaining macromechanical retention provided by the axial opposing pulpal walls and microretention attained with the use of adhesive cementation. Review results Endocrowns require a decay-oriented preparation taking advantage of both the adhesion and the retention from the pulp-chamber walls, they are strongly indicated in endodontically treated molars in cases where minimal interocclusal space and curved or narrow root canals are present and they should be manufactured from materials that can be bonded to the tooth structure. Conclusion Endocrowns are a reliable alternative to traditional restorative choices, given that the clinicians respect the requirements and indications describing this technique. Clinical significance Traditional restorative techniques demanding tooth substance removal and minimizing the opportunity for reinterventions should be reconsidered.

The purpose of this study was to investigate the surface characteristics and color stability of gingiva-colored composite restorative materials (Anaxgum&mdash, ANG, Ceramage&mdash, CMG and Gradia Gum&mdash, GRG). The microstructure, composition, degree of conversion (DC %) and 3D roughness (Sa, Sz, Sdr, Sc) were examined by LV-SEM/EDS, ATR-FTIR and optical profilometry, respectively. For the color stability (CIE L*, a*, b* system) and hardness (HV), measurements were performed at baseline and after 30 days storage in distilled water, coffee and red wine. The ANG and GRG contain prepolymerized particles in aromatic and aliphatic resin matrices, respectively, whereas CMG contains inorganic zirconia silicate/silica particles, in an aromatic resin matrix, with a smaller particle size and a higher surface area fraction. Urethane monomers were mainly identified in CMG and GRG. The DC% showed statistically insignificant differences between the materials. The same applied for the roughness parameters, except for the greatest Sdr in CMG. ANG showed a color difference (&Delta, E) of &gt, 3.3 after immersion in all media, CMG in coffee and wine and GRG only in coffee. Sc was the only roughness parameter demonstrating correlations with the &Delta, L*, &Delta, b* and &Delta, E*. The HV values showed insignificant differences between the storage conditions per material. There are important differences in the color stability of the materials tested, which were mostly affected by the roughness parameters due to variations in their microstructure.

Aim: The precise framework fit is important for the success of implant restorations. The purpose of the present study was to examine the effect of two different impression materials both of their medium viscosity on the master cast accuracy when parallel and inclined implants were used. Materials and Methods: An epoxy master cast with three implants was fabricated. The first two implants were parallel to each other and perpendicular to the horizontal plane and the third implant had a 250 inclination in reference to the other two. A passively fitting metal framework that was fabricated over this master cast was used to measure accuracy of fit. Five closed tray impressions for each medium viscosity material (polyether and polyvinyl-siloxane) tested were taken and the respective ten stone casts with three implant analogs were fabricated. The metal framework in the master cast, was fixed in the new specimens and the micro-gap between this prosthesis and the implant analogs was evaluated. The specimens were observed to an optical microscope and digital photography. Results and Conclusion: The data were statistically analysed using a computer software and t-test. Polyether exhibited higher micro-gap mean values (93,4 to 61,8 μm) compared to polyvynil siloxane (30,47 to 14,83μm). The differences were statistically significant only for implant B. The categorical regression analysis (p < 0.01) for all implants showed that the marginal micro-gap was affected by the impression material (94.1%) and significantly by the type of it. The micro-gap values were higher for polyether compared to polyvinyl-siloxane. The torqued implant did not exhibit any statistically significant effect.

Svrha: Svrha ovoga rada bila je procijeniti utjecaj termocikliranja na čvrstoću savijanja poliamidnog materijala za bazu proteze. Materijali i metode: Testiran je poliamidni protezni materijal (Valplast), a kao kontrola korišten je PMMA (Vertex). Trideset primjeraka svakog materijala izrađeno je za ispitivanje čvrstoće savijanja prema standardu ISO 1567. Svi su uzorci pripremljeni i čuvani 48 sati u vodi na temperaturi od 37 °C, a zatim su podijeljeni u tri jednake skupine (n = 10). Ispitivanje čvrstoće savijanja obavljeno je odmah nakon uranjanja u vodu te nakon termocikliranja (5 °C/55 °C, 2c/min.) poslije 3000 i 5000 ciklusa. Ispitivanje fleksibilnosti provedeno je na trima točkama u univerzalnom stroju za testiranje na brzini križanja od 5 mm/min. Konačna čvrstoća savijanja izračunata je formulom: FS = 3PL/2bd2. Dvosmjerna ANOVA s Tukeyjevim post hoc testom primijenjena je na razini .05 statističke značajnosti. Rezultati: tatistički značajno smanjenje čvrstoće savijanja zabilježeno je nakon termocikliranja poslije 3000 ciklusa za PMMA-e i 5000 ciklusa za oba materijala. Čvrstoća savijanja PMMA-e bila je značajno veća u odnosu na poliamid za sve ispitane uvjete (p < 0,05). Zaključak: Termocikliranje je vrlo nepovoljno djelovalo na čvrstoću savijanja materijala poliamida i materijala PMMA za bazu proteze., Objective: The aim of the present study was to evaluate the influence of thermocycling on the flexural strength of a polyamide base denture material. Materials and methods: A polyamide denture base material (Valplast) was tested, whereas a PMMA material (Vertex) was used as a control. Thirty specimens of each material were fabricated for flexural strength testing according to ISO 1567. They were prepared and stored in water at 37°C for 48 hours. The specimens of each material were divided into three equal groups (n=10). Flexural strength testing was performed immediately after water storage and after thermocycling (5°C / 55°C, 2 c/min) for 3000 and 5000 cycles. A three point flexural test was performed on a universal testing machine at a crosshead speed of 5 mm/min. The final flexural strength was calculated using the formula: FS = 3 PL/2 bd2. A two-way ANOVA with post-hoc analysis using Tukey’s procedure was applied at .05 level of statistical significance. Results: A statistically significant reduction in flexural strength was recorded after thermocycling at 3000 cycles for PMMA and at 5000 cycles for both materials. The flexural strength of PMMA was significantly higher compared to polyamide for all the conditions tested (p

AIM. This paper is an attempt to compare and analyze the various mathematical models for defining the dental arch curvature of children in normal occlusion based upon a review of available literature. Background. While various studies have touched upon ways to cure or prevent dental diseases and upon surgical ways for teeth reconstitution to correct teeth anomalies during childhood, a substantial literature also exists, attempting to mathematically define the dental arch of children in normal occlusion. This paper reviews these dental studies and compares them analytically. Method. The paper compares the different mathematical approaches, highlights the basic assumptions behind each model, underscores the relevancy and applicability of the same, and also lists applicable mathematical formulae. Results. Each model has been found applicable to specific research conditions, as a universal mathematical model for describing the human dental arch still eludes satisfactory definition. The models necessarily need to include the features of the dental arch, such as shape, spacing between teeth and symmetry or asymmetry, but they also need substantial improvement. Conclusions. While the paper shows that the existing models are inadequate in properly defining the human dental arch, it also acknowledges that future research based on modern imaging techniques and computeraided simulation could well succeed in deriving an allinclusive definition for the human dental curve till now eluding the experts.

Objectives To investigate the colour stability of four indirect composite restorative materials after accelerated aging. Methods Four indirect composites (Gradia, Signum+, HFO and Adoro) were used. For each material, six specimens were prepared and subjected to accelerated aging (Suntest CPS+, Atlas, Chicago, IL, USA) according to ISO 7491. A Dr. Lange Microcolor Data Station colorimeter (Braive Instruments, Liege, Belgium) was used to measure specimen colour before and after aging. Measurements were performed according to the CIE L*a*b* system, and the mean L*, a* and b* values for each material were calculated. The equation DeltaE = [(DeltaL*)2 + (Deltaa*)2 + (Deltab*)2](1/2) was used to measure the total colour change (DeltaE), where DeltaL*, Deltaa* and Deltab* are the differences in the respective values before and after aging. One-way ANOVA were used to determine statistically significant differences in DeltaL*, Deltaa*, Deltab* and DeltaE. Results No statistically significant differences were found in DeltaL*, Deltaa*, Deltab* and DeltaE among the materials tested (PDeltaL*=.063; PDeltaa*=.521; PDeltab*=.984 and PDeltaE=.408). After aging, Gradia specimens showed an increase in lightness (DeltaL*=0.36) and a green-yellow shift (Deltaa*=-1.18, Deltab*=0.6), while Signum+ specimens exhibited an increase in lightness (DeltaL*=0.5) and a green-blue shift (Deltaa*=-0.9, Deltab*=-0.45). HFO specimens exhibited an increase in lightness (DeltaL*=0.75) and a green-yellow shift (Deltaa*=-1.3, Deltab*=0.06), and Adoro specimens exhibited an increase in lightness (DeltaL*=2.07) and a green-yellow shift (Deltaa*=-1.3, Deltab*=0.68). Conclusions Colour changes were found to be within accepted values of perceptibility and clinical acceptance after accelerated aging, and no statistically significant differences were found in DeltaL*, Deltaa*, Deltab* and DeltaE among the materials tested.