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AIM: The aim of this study was to evaluate and compare the tensile bond strength of zirconia copings subjected to three different surface treatment methods and cemented with three different luting agents. MATERIALS AND METHODS: Seventy-two extracted maxillary premolar teeth were prepared to receive zirconia copings milled using computer-aided design/computer-aided manufacturing technology, which were divided into 9 groups of 8 specimens each. Three surface treatment protocols such as hydrofluoric acid etch treatment, air abrasion with 110-µm aluminum oxide (Al2O3), and tribochemical silica coating (Rocatec) treatment were carried out, and copings were cemented with three luting agents such as resin-modified glass ionomer cement (RelyX luting 2), 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP) resin cement (Panavia F 2.0) and 4-methacryloxyethyl trimellitic acid (4-META) resin cement (G-Cem). Tensile bond strength of the copings was tested in a universal testing machine. Zirconia copings fabricated on the prepared extracted tooth. After the three surface treatments and cementing the zirconia crowns with three luting agents tensile bond strength is tested. The mean and standard deviations (SD) were calculated for the nine groups using one-way ANOVA, followed by Tukey-Kramer post hoc using the SPSS software. RESULTS: The ANOVA test showed that the measured mean bond strength values were 4.22 MPa (tribochemicalsilica coating and MDP resin), 2.71 MPa (air abrasion and MDP resin), 2.61 MPa (tribochemical treatment with META), and 0.66 MPa (RelyX with air abrasion). According to the pairwise comparison of Tukey's honestly significant difference test, significant differences were exhibited among all the groups (P < 0.05). CONCLUSION: Tribochemical silica coating in combination with 10-MDP and 4-META adhesive resins provided the maximum bonding for zirconia copings.
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Success of the prosthesis after mandibular resection is related directly to the amount of the remaining bone and soft tissue present. The prognosis for mandibulectomy patients becomes less favorable as the size of the resection increases. Prosthetic rehabilitation for such patients is a challenge for clinicians. Without preprosthetic reconstructive surgery, denture fabrication for mandibulectomy patients becomes extremely difficult. Telescopic dentures is a modality of treatment consisting of an inner or primary telescopic coping which is permanently cemented to an abutment and an outer or secondary telescopic coping which is attached to the prosthesis. These copings protect the abutment from dental caries and thermal irritations and also provide retention and stabilization of the secondary coping. The secondary coping engages the primary copings to form a telescopic unit and it provides retention and stability to the prosthesis. This clinical report aims at utilizing the remaining natural teeth for a mandibular overdenture with telescopic coping.
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The success of the dental restorations largely depends on its esthetics, although various literature reviews recommend that anterior teeth midline be placed coinciding the facial midline, the amount of acceptable deviation between facial and dental midline has not been fully investigated. To observe the acceptable deviation between the dental and facial midline. Facial photographs of 200 students aged about 18-30 years of both sexes, without any missing teeth, with complete alignment of anterior teeth, were selected and scanned on to computer screen. Using specialized programme, the crown width of the central incisor in the mouth and on photograph was ensured constant. The distance between the facial midline, (obtained by bisecting intercanthal line) and the mesial surfaces of the central incisors were read on the computer. 44.4 % Boys and 55 % of Girls showed deviation between dental and facial midline in the range of 0-1 mm. while, 54 % of boys and 33 % of girls showed deviation of the dental and facial midline in the range 1-2 mm. 37 % of boys and 8 % of girls showed deviation of dental midline with facial midline with the range of 2-3 mm. 80 % of the study population showed maxillary and mandibular dental midlines never coincide. Majority of the study population showed deviation between facial midline and anterior teeth midline within the range of 0-1 mm.
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AIM: The aim of this study was to find out the nature of occlusion and tooth contact during various eccentric mandibular movements in young adults with class I occlusion. MATERIALS AND METHODS: The sample consisted of 100 young adults with class I occlusion with full complement of teeth. Anterior disclusion in centric occlusion was demonstrated using a shim stock interposed between the upper and lower anteriors. Disclusion of posteriors was ascertained during 1.5 mm straight protusion and in edge-to-edge protrusion, visually as well as using a silk floss method. Posterior disclusion was also verified during lateroprotrusion and crossover. Besides these occlusal wear of teeth also were observed. RESULTS: The results of this study showed that the anterior disclusion is seen only in one-fourth of the subjects compared to almost three-fourth showing posterior disclusion. Mutually protected occlusion was also seen only in one-fourth of the subjects. Canine protective mechanism is seen in a relatively large number of subjects, but it was not overwhelmingly predominant. No correlation could be established between cuspid wear and the type of occlusion. A relatively high percentage of subjects showed wear on posterior teeth when there was no posterior disclusion. CONCLUSION: From the above study it is seen that posterior disclusion is acknowledged as a common factor except when a bilateral balance is present. Since bilateral balance is harmful, the ideal occlusal relationship in eccentric movements is in favor of posterior disclusion. Posterior disclusion is easily obtainable when restorations are planned. CLINICAL SIGNIFICANCE: From the findings and results it has been possible to make some contributions on the nature of tooth contacts and disclusion during various eccentric movements and compare it with the requirements of ideal occlusion.
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Oclusão Dentária , Mandíbula/fisiologia , Coroa do Dente/fisiologia , Adolescente , Adulto , Dente Pré-Molar/fisiologia , Dente Canino/fisiologia , Oclusão Dentária Balanceada , Oclusão Dentária Central , Feminino , Humanos , Incisivo/fisiologia , Masculino , Dente Molar/fisiologia , Movimento , Atrito Dentário/patologia , Coroa do Dente/patologia , Adulto JovemRESUMO
BACKGROUND: The aim of the study is to compare the relationship of the occlusal plane to 3 different ala-tragal lines, namely the superior, middle and inferior lines, in individuals having different head forms and its relation to the Frankfort horizontal plane. METHODOLOGY: A total of 75 lateral cephalometric radiographs of subjects with natural dentition, having full complement of teeth, between the age group of 18-25 were screened and selected. Lateral cephalogram were made for each subjects in an open mouth position. Prior to making the lateral cephalogram, radiopaque markers were placed on the superior, middle and inferior tragus points and on the inferior border of the ala of the nose. Cephalometric tracing was done over each cephalogram. RESULTS: In mesiocephalic head form the middle ala-tragal line was most parallel to the occlusal plane having a mean angle of (1.96°). In dolichocephalic headform, the superior ala-tragal line was most parallel to the occlusal plane having a mean angle of (0.48°). In brachycephalic head form, the middle ala-tragal line was most parallel to the occlusal plane having a mean angle of (2.08°). The mean angulations of occlusal plane to FH plane is 11.04°, 10.16° and 10.60° in mesiocephalic, dolichocephalic and brachycephalic head forms, respectively. RESULTS AND CONCLUSION: The study concludes that the middle ala-tragal line can be used as a reference for the mesiocephalic head form and the superior ala-tragal line for the dolichocephalic and brachycephalic head form as a reference to establish the occlusal plane.
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Pontos de Referência Anatômicos/diagnóstico por imagem , Cefalometria/métodos , Oclusão Dentária , Cabeça/diagnóstico por imagem , Adolescente , Adulto , Cefalometria/normas , Estudos de Coortes , Prótese Total , Pavilhão Auricular/diagnóstico por imagem , Feminino , Humanos , Masculino , Nariz/anatomia & histologia , Adulto JovemRESUMO
BACKGROUND: Dentinal hypersensitivity is a very common complaint of patients undergoing crown and bridge restorations on vital teeth. Of the many desensitizing agents used to counter this issue, desensitizing laser treatment is emerging as one of the most successful treatment modality. However, the dentinal changes brought about by the desensitizing laser application could affect the bond strength of luting cements. MATERIALS AND METHODS: Freshly extracted 48 maxillary first premolars, which were intact and morphologically similar were selected for the study. The specimens were divided into two groups, an untreated the control group and a desensitizing laser-treated group, which were exposed to Erbium, Chromium: Yttrium, Selenium, Galium, Garnet laser at 0.5 W potency for 15 s. Each of the above two groups were again randomly divided into two subgroups, on to which full veneer metal crowns, which were custom fabricated were luted using glass-ionomer and resin luting cements, respectively. Tensile bond strength of the luting cements was evaluated with the help of a Universal Testing Machine. Statistical analysis of the values were done using descriptive, independent samples' test, and two-way ANOVA test. RESULTS: The tensile bond strength of crowns luted on desensitizing laser treated specimens using self-adhesive resin cement showed a marginal increase in bond strength though it was not statistically significant. CONCLUSION: The self-adhesive resin cements could be recommended as the luting agent of choice for desensitizing laser treated abutment teeth, as it showed better bond strength.
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OBJECTIVES: To evaluate and compare the flexural strength and the elastic moduli of three provisional crown materials (methyl methacrylate based autopolymerized resin, bis acryl composite based autopolymerized resin and urethane dimethacrylate based light polymerized resin) after storing in artificial saliva and testing at intervals of 24 hours and 7 days. STUDY DESIGN: A metal master mould with four slots of dimensions 25x2x2 mm was fabricated to obtain samples of standard dimensions. A total of 135 specimens were thus obtained with 45 each of three provisional materials. Further 15 samples of each group were tested after storing for one hour at room temperature and again at intervals of 24 hours and 7 days after storing in artificial saliva. Three point flexural tests were carried out in the universal testing machine to calculate the flexural strength and the elastic modulus. The changes were calculated and data was analyzed with Fisher's test and ANOVA. RESULTS: The flexural strength of the methyl methacrylate resin reduced significantly while bis-acrylic composite resin showed a significant increase in its flexural strength after storing in artificial saliva for 24 hours and the values of both remained constant thereafter. Contrary to these findings, light polymerized resin showed a significant decrease in flexural strength after storing in artificial saliva for 24 hours and then significantly increased in flexural strength after 7 days. However the changes in the values for elastic modulus of respective materials were statistically insignificant. CONCLUSION: Methacrylate based autopolymerizing resin showed the highest flexural strength and elastic moduli after fabrication and after storing in artificial saliva and for 24 hours and 7 days. Bis-acrylic composite resin showed the least flexural strength and elastic moduli. Key words:Provisional restorations, interim restorations, Methyl Methacrylate, composite restoration, flexural strength, elastic moduli.
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The role of a prosthodontist in the management of cleft lip & palate patients is pertinent involving restoration of mastication, facial harmony, dental harmony and phonation. This article presents the prosthodontic rehabilitation of a congenitally bilateral cleft lip and palate patient with a unique method which fulfilled the patient's needs, esthetics and psychological well being.
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Forensic dentistry is finding increased application in identifying deceased individuals. Incorporating patient identification system in dentures is one of the measures taken in this regard. There are several denture identification measures, each having their own merits and demerits. This article describes a new denture identification system using Quick Response Code incorporated in dentures. This identification system can be very cost-effective, store lot of patient-related information and be easily accessible to the dentist...
A identificação de indivíduos falecidos é uma demanda crescente em Odontologia. A incorporação de sistemas de identificação na prótese total de pacientes é um procedimento de possível. Existem vários sistemas de identificação em próteses totais, cada um com seus próprios méritos e deméritos. Este artigo descreve um novo sistema de identificação de dentadura utilizando o código QR incorporado em próteses totais. Este sistema de identificação é de baixo custo, armazena grande quantidade de informações relacionadas ao paciente e é de fácil acesso ao dentista...