Effect of laboratory and chairside polishing methods on the surface topography of occlusal splint materials manufactured using conventional, subtractive and additive digital technologies / Efeito de métodos de polimento em laboratório e em consultório na topografia de superfície de materiais de splint oclusal fabricados usando tecnologias digitais convencionais, subtrativas e aditivas

Objetivo: Este estudo avaliou as propriedades de polimento dos materiais de splint oclusal obtidos usando métodos de fabricação subtrativos e aditivos com os procedimentos de polimento laboratorial (LP) e polimento em consultório (CP). Material e Métodos: As amostras (N=180, n=60 para cada grupo) foram fabricadas usando um dos seguintes métodos: método de fabricação subtrativo (SMM) (M-PM Disc, Merz Dental GmbH), método de fabricação aditivo (AMM) (Freeprint Splint 2.0, DETAX GmbH & Co. KG) e o método de fabricação convencional (CMM) (Promolux HC, Merz Dental GmbH). Seguindo os procedimentos de LP e CP, a rugosidade da superfície dos espécimes foi medida usando um perfilômetro de superfície digital. Um espécime representativo foi selecionado de cada grupo, e uma imagem de microscópio eletrônico de varredura (SEM) foi obtida. Resultados: Tanto o método de fabricação quanto os procedimentos de polimento afetaram significativamente os resultados (P<0,01). Os termos de interação também foram significativos (P<0,001). Conclusão: Com ambos os métodos de polimento, a rugosidade superficial do grupo AMM foi a maior e a do grupo CMM a menor. Embora o procedimento CP tenha sido mais eficaz do que LP com ambos os métodos, a rugosidade da superfície ficou abaixo do limite de 0,2 µm após ambos os procedimentos de polimento testados (AU)

Objective: This study evaluated the polishing properties of the occlusal splint materials obtained using subtractive and additive manufacturing methods with the laboratory-type polishing (LP) and chairside-type polishing (CP) procedures. Material and Methods: Specimens (N=180, n=60 each group) were manufactured using one of the following methods: subtractive manufacturing method (SMM) (M-PM Disc, Merz Dental GmbH), additive manufacturing method (AMM) (Freeprint Splint 2.0, DETAX GmbH & Co. KG), and the conventional manufacturing method (CMM) (Promolux HC, Merz Dental GmbH). Following LP and CP procedures, surface roughness of the specimens was measured using a digital surface profilometer. One representative specimen was selected from each group, and a scanning electron microscope (SEM) image was made. Results: Both the manufacturing method and the polishing procedures significantly affected the results (P<0.01). Interaction terms were also significant (P<0.001). Conclusion: With both polishing methods, surface roughness of the AMM group was the highest and the CMM group the least. Although the CP procedure was more effective than LP with both methods, surface roughness was below the 0.2 µm threshold after both polishing procedures tested. (AU)

CAD/CAM single-retainer monolithic zirconia ceramic resin-bonded fixed partial dentures bonded with two different resin cements: Up to 40 months clinical results of a randomized-controlled pilot study.

PURPOSE: This pilot study was part of a larger study planned for the future which aimed to compare the clinical success of two different resin cements used in the cementation of CAD/CAM single-retainer monolithic zirconia ceramic resin-bonded fixed dentures (RBFPDs). METHODS: Twenty-four RBFPDs were fabricated with monolithic zirconia (Katana™ Zirconia HT, Kuraray Noritake Dental Inc, Tokyo, Japan). Panavia F2.0 (PF2.0; n = 12) and Panavia V5 (PV5; n = 12) were used for cementation. The survival period was defined as the time when the restoration was placed in the mouth and lasted until an irreparable damage occurred. The repairable failures were identified as relative and irreparable failures were identified as absolute failure. The survival rate of the RBFPDs was determined by the Kaplan-Meier estimator. Statistical significance was set at p < 0.05. RESULTS: The mean observation times of the PF2.0 group and the PV5 group were 40.45 ± 6.15 months and 40.18 ± 6.41 months, respectively. Four failures occurred in the PF2.0 group. No failure was observed in the PV5 group. The curves of survival rate (PF2.0 = 80%, PV5 = 100%) showed no statistically significant difference (p = 0.031), although success rate (PF2.0 = 66.7%, PV5 = 100%) showed statistically significant difference (p = 0.317). CONCLUSION: Up to 40 months mean follow-up period, performance of RBFPDs bonded with PV5 was better than with PF2.0. CLINICAL SIGNIFICANCE: For clinicians, it is a matter of hesitation to apply single-retainer RBFPDs. This study contains results of 40 months (minimum 32, maximum 50.47 months) clinical follow-ups of single-retainer RBFPDs. These results will enlighten clinicians about the clinical success of the resin cement type for single-retainer monolithic zirconia ceramic RBFPDs.

Influence of Stabilization Splint Thickness on Temporomandibular Disorders.

PURPOSE: To assess the effect of stabilization splint (SS) thickness on temporomandibular disorders (TMDs). MATERIALS AND METHODS: Participants were selected from patients who applied to the clinic with a complaint of temporomandibular disorders (TMDs). Symptoms were evaluated with the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). Regarding the treatment plan, patients were divided into two groups: the 2-mm-thick splint group (2-mm TSG) and the 4-mm-thick splint group (4-mm TSG). They used SSs at night (8 hours) and were recalled 1, 2, 3, and 6 months after splint insertion. At the end of the study, 72 patients (2-mm TSG = 39, 4-mm TSG = 33) had completed the 6-month follow-up. The SPSS program was used for statistical analysis. The results of the analysis were evaluated at a significance level of .05. RESULTS: Pain in the muscles decreased significantly in the muscle disorders and combined groups (both 2- and 4-mm TSG) after 6 months of treatment (P < .05). In the combined group, TMJ sounds significantly decreased after 6 months of treatment, and there was a statistically significant difference between the 2-mm TSG and the 4-mm TSG (P = .045). Also, in the combined group, maximum unassisted opening (MUO) values of patients treated with 2-mm-thick splints decreased after 6 months of treatment (P = .022). CONCLUSION: Both 2-mm-thick and 4-mm-thick splints were effective in the treatment of muscle disorders and disc displacements, especially in muscle-related pain and TMJ sound symptoms.

The soap carving versus the digital sculpting: Evaluation of students' preferences and performance in dental anatomy course: Pilot study.

PURPOSE/OBJECTIVES: The aim of this study was to evaluate the change in students' preferences between soap carving (SC) and digital sculpting (DS) methods after obtaining tooth with both methods, their opinions about the methods and their performance in the dental anatomy course. MATERIALS AND METHODS: The SC and DS methods were demonstrated. Students were asked to obtain a maxillary central incisor by both methods and to record time. Students' preferences were asked both before and after applying both methods. The level of significance for statistical analysis was set at p ≤ .05. RESULTS: Forty first year preclinical students (24 female, 16 male) participated in this study. Their mean age was 19.38 years ±1.00 year. There was a statistically significant difference between the mean time of the DS method according to gender (p = .004) and the mean time of DS and SC methods for females (p = .015). There was also a statistically significant difference between preferences of students for "In the future while treating the patient in the clinic, I learned with ………… method in the preclinic will be more useful for me." statement, before and after applying both methods (p = .034). CONCLUSIONS: The obtaining the tooth of the students with DS method were longer than with SC method (especially in the females). After applying both methods, the students changed their minds that learning the information about the SC and DS methods would have a similar effect when treating patients in the clinic.

Comparison of Digital and Conventional Impression Methods by Preclinical Students: Efficiency and Future Expectations.

AIMS AND OBJECTIVES: The purpose of this study is to compare digital and conventional impression methods by preclinical students in terms of time and ease and to evaluate their preferences and future expectations. MATERIALS AND METHODS: Twenty volunteered, 2nd year preclinical students (11 females and 9 males) participated in this study. Students took digital and conventional impressions of the left lower first molar which was made full ceramic crown preparation and opposite full arch from a typodont model (Frasaco, Frasaco GmbH, Tettnang, Germany). They used intraoral scanner (CEREC Omnicam, Sirona Dental GmbH, Bensheim, Germany) for digital impression and also used additional type (Express XT Penta H, 3M ESPE, Seefeld, Germany) and condensation type (Zetaplus, Zhermack SpA, Badia Polesine, Italy) silicones for conventional impression. Their taking impression time was measured. Before taking impression and after taking impression, two kinds of questionnaires were conducted to students about their preference, ease of impression methods, and their future expectations. Statistical analysis was performed by IBM SPSS 23 and Excel 2010 version. Differences between conventional and digital impression in terms of time were analyzed by student's-t paired test and effect of gender was analyzed by students's-t independent test. RESULTS: There were statistically significant differences between digital and conventional impression methods in terms of taking impression and total impression time (P < 0.001). But there wasn't any statistically significant difference between two methods in terms of preparation time. About 85% of students preferred the digital impression method and also 85% of students found that the digital impression method was easy. 95% of students expected to find intraoral scanner in the clinic where working first time. CONCLUSIONS: As a result of this study, it has been seen that the students preferred the digital impression method to the conventional impression method and found that the digital impression method was easier.

Repair Protocol of Porcelain Laminate Veneers Through Reattachment of the Fractured Ceramic Piece: A Technical Report / Protocolo de reparo de laminados de porcelana através de recolocação da peça de cerâmica fraturada: um relato técnico

This technical report has been developed to repair the ceramic laminate veneer without removing after fracture. The bonding between the tooth and the laminate veneer is very strict, thus removing the restoration is difficult. The disadvantages such as the loss of tissue from the tooth, the cost and time loss are eliminated with this technique. In this technical report, the cementation of porcelain to porcelain in the presence of the fractured piece is explained step by step (AU)

Este relato técnico foi desenvolvido para reparar o laminado cerâmico sem remoção após fratura. A união entre o dente e o laminado é muito rígida, remover a restauração é difícil. As desvantagens como a perda de tecido do dente, o custo e a perda de tempo são eliminadas com esta técnica. Neste relato técnico, a cimentação de porcelana em porcelana na presença da peça fraturada é explicada passo a passo (AU)

Comparison of digital and conventional impression techniques: evaluation of patients' perception, treatment comfort, effectiveness and clinical outcomes.

BACKGROUND: The purpose of this study was to compare two impression techniques from the perspective of patient preferences and treatment comfort. METHODS: Twenty-four (12 male, 12 female) subjects who had no previous experience with either conventional or digital impression participated in this study. Conventional impressions of maxillary and mandibular dental arches were taken with a polyether impression material (Impregum, 3 M ESPE), and bite registrations were made with polysiloxane bite registration material (Futar D, Kettenbach). Two weeks later, digital impressions and bite scans were performed using an intra-oral scanner (CEREC Omnicam, Sirona). Immediately after the impressions were made, the subjects' attitudes, preferences and perceptions towards impression techniques were evaluated using a standardized questionnaire. The perceived source of stress was evaluated using the State-Trait Anxiety Scale. Processing steps of the impression techniques (tray selection, working time etc.) were recorded in seconds. Statistical analyses were performed with the Wilcoxon Rank test, and p < 0.05 was considered significant. RESULTS: There were significant differences among the groups (p < 0.05) in terms of total working time and processing steps. Patients stated that digital impressions were more comfortable than conventional techniques. CONCLUSIONS: Digital impressions resulted in a more time-efficient technique than conventional impressions. Patients preferred the digital impression technique rather than conventional techniques.