Comparison of physical and mechanical properties of three different restorative materials in primary teeth: an in vitro study.

OBJECTIVE: Physical and mechanical properties of three different (Ketac Molar Easymix, Dyract XP, Cention N (CN)) restoratives with different ingredients were evaluated. MATERIALS AND METHODS: Four groups were obtained; Group 1: CN LightCure, Group 2: CN SelfCure, Group 3: Ketac Molar Easymix and Group 4: Dyract XP. Disk-shaped samples (n = 10) were prepared and evaluated for the surface roughness test using a profilometer. For the flexure strength test, 2 × 2 × 25 mm bar-shaped samples (n = 10) were prepared, and a three-point bending test was applied to the samples. After preparing cavities for microleakage tests, teeth were restored with restoratives, immersed in dye, and microleakage was assessed. For the microtensile bond strength (µTBS) test, ten sticks were obtained for each group and were stressed under tension. RESULTS: According to surface roughness tests, CN SelfCure showed the lowest value (0.13 µm), while Ketac Molar Easymix showed the highest value (0.28 µm), and significant differences were found between the groups. In flexural strength tests, the highest values were seen in CN SelfCure (82.94 MPa), with statistically significant differences between the groups. When CN SelfCure was applied with an adhesive, the teeth showed statistically decreased leakage than other groups on the gingival side. Higher leakage values were seen on the gingival side than the occlusal side in most groups, and the SelfCure groups showed decreased leakage than the LightCure groups. According to µTBS tests, the highest value was obtained in CN SelfCure-Adhesive group, while the lowest was in CN LightCure-Non-adhesive group. When µTBS was evaluated regardless of adhesive use, the SelfCure groups showed higher µTBS values than the LightCure groups. As a result of the µTBS and microleakage test, the difference between the use of CN with and without adhesive, regardless of the polymerization type, was found to be significant (p < 0.05). CONCLUSION: Cention N showed better properties in SelfCure mode, compared to the rest materials tested, but further in vitro and in vivo studies are needed to investigate the effect of different polymerization modes and the oral environmental conditions.

Evaluation and comparison of mineral trioxide aggregate and biodentine in primary tooth pulpotomy: Clinical and radiographic study.

OBJECTIVES: Pulpotomy is the common therapy for cariously exposed pulps in symptom-free primary molar teeth. For many years, researchers have searched for an ideal material that allows regeneration of the residual pulp. The purpose of this study was to evaluate the efficacy of mineral trioxide aggregate (MTA), Biodentine as a pulpotomy medicament in primary teeth, both clinically and radiographically. MATERIALS AND METHODS: A total of 25 children (50 human primary molar teeth) aged between 5 and 9 years were selected in this randomized clinical study. The patients were randomly assigned to receive the pulpotomy medicaments in either [Group 1]: MTA or [Group 2]: Biodentine. All pulpotomized teeth were restored with stainless steel crowns and evaluated clinically and radiologically at 1, 3, 6 and 12 months. Statistical analysis using Mann-Whitney U test and Fisher's exact test, and chi-square test was performed to determine the significant differences between the groups. RESULTS: Clinical and radiological success rates were 96 and 80% in Group 1 and 96 and 60% in Group 2, respectively. There were no significant differences between the groups (P > 0.05). The radiographic success rates decreased in the controls, but there were no significant differences. CONCLUSION: Biodentine showed similar clinical and radiographic results as MTA in the 12-month evaluation and can be safely used as a pulpotomy medicament.

Flexural and Microtensile Bond Strength of Bulk Fill Materials.

AIM: The aim of this study was to evaluate the flexural and µTBS of bulk-fill materials. STUDY DESIGN: Bulk-fill materials SDR, X-trabase (XTR) and TetricEvoCeramBulkFill (EVO) were used in this study. To test flexural strength, 25x2x2mm samples were prepared and tested with three point bending test. To test the microtensile bond strength (µTBS), two blocks (4x4x4mm) were prepared for each material. In Group A+B, acid-etching was applied to the surface of one of these blocks and no acid-etching was applied in Group B. After applying bonding agent, two blocks were placed into the mold and composite resin (COMP; Tetric N-Ceram) was applied with incremental layering. To evaluate the µTBS of primary dentin, the bulk-fill materials were applied to flat dentin up to 4mm. The new blocks and the teeth were sectioned to obtain sticks and the sticks were loaded in tension until failure. Flexural and microtensile bond strength was calculated based on failure load. RESULTS: The ranking of materials with regards to flexural strength values were SDR>XTR>EVO>COMP,respectively. In GroupA+B, the µTBS values were XTR>SDR>EVO and were XTR>EVO>SDR in GroupB (p>0.05). The µTBS values of these materials to dentin were XTR>EVO>SDR (p>0.05). CONCLUSION: Within the limitations of this study, the use of a bonding agent without acid-etching showed positive interactions between base materials and composite resin and there were no significant differences in µTBS of these materials to dentin.

A comparative clinical study of three fissure sealants on primary teeth: 24-month results.

AIM: The purpose of this study was to evaluate the clinical success of three fissure sealants(FSs) with different contents on primary teeth. STUDY DESIGN: Three FSs were used to seal 150 primary molars in 75 children aged 4-7 years. All FSs were placed on occlusal surfaces in a split-mouth and randomized clinical trial. For patients in Group1,amorphous calcium phosphate(ACP) containing resin-based sealant(RBS)(Aegis) was applied to a primary molar tooth on one side ,and non-fluoride RBS(Helioseal) FS was applied to symmetrical molar tooth. For patients in Group2, fluoride-containing RBS(Helioseal F) was applied to a primary molar tooth on one side, and Helioseal FS was applied to symmetrical molar tooth. For patients in Group3,Helioseal FS was applied to a primary molar tooth on one side, and Aegis FS was applied to symmetrical molar tooth. Clinical evaluation of FSs was carried out to assess retention, marginal discoloration, marginal adaptation,and the presence of caries in months 1,3,6,12,18 and 24 after FS application. RESULTS: There were no significant differences for all criteria in groups 2 and 3(p≯0.05). In group 1,cumulative success rates according to 24 months' follow-up were statistically insignificant during the comparisons performed in terms of retention, marginal adaptation, and presence of caries(p≯0.05). Marginal discoloration was found to be statistically significant(p<0.05). CONCLUSION: RBS containing ACP or fluoride may be more effective than conventional RBS for caries prevention.

Effects of different cavity-disinfectants and potassium titanyl phosphate laser on microtensile bond strength to primary dentin.

AIM: The aim of this in vitro study was to compare the effects of different cavity-disinfectants and potassium titanyl phosphate (KTP) laser on microtensile bond strength to primary dentin. Chlorhexidine (CHX), propolis (PRO), ozonated water (OW), gaseous ozone (OG) and KTP laser were used for this purpose. METHODOLOGY: Twelve primary molar teeth were used in this study. One-third of the teeth (from coronal portion) were removed to obtain flat surfaces. After applying the cavity-disinfectants, an adhesive (prime and bond NT) was applied to dentin surfaces, and composite crowns were built up. One group received no pretreatment and was set as a control (CONT). Ten sticks were obtained from these samples and were stressed in tension until failure using a universal testing machine and the data were recorded. RESULTS: The mean strength values (in MPa) of the sticks were OW (11.12) > KTP (9.58) > CHX (7.58) > PRO (7.42) > CONT (6.38) > OG (5.84) and OW showed significantly higher results than the other groups, except KTP group (P < 0.05). CONCLUSIONS: OW and KTP might be used safely without compromising the bond strength of restorative materials.

Accuracy of three different apex locators and visual exam in primary teeth with and without root resorption in vitro.

AIM: The aim of this study was to evaluate the accuracy and reliability of three apex locators (EndoMaster, Raypex, DentaPort ZX) and visual assessment in primary molar teeth in vitro. MATERIALS AND METHODS: Twenty-four extracted human primary molar teeth with and without root resorption were used in this study. After endodontic access preparation, root canal length was visually measured by means of a K file; then the teeth were embedded into alginate and the roots were measured again by mans of the three apex locators. The results were collected in SPSS 15.0 and statistical evaluations were completed by one-way ANOVA and Kruksal-Wallis test. RESULTS: The measurements closest to the visually determined length were obtained with EndoMaster. No statistically significant differences were found between visual and apex locators lengths (p>0.05). CONCLUSION: Within the limitations of this study, the use of apex locators would be useful in the endodontic treatment of primary teeth.

Traumatic dental injuries in children. Experience of a hospital in the central Anatolia region of Turkey.

AIM: The purpose of this retrospective study was to identify traumatic dental injuries by using the documentations of children (range 0-14 years, average age: 10.79±2.06) with dental trauma who referred to Cumhuriyet University, Faculty of Dentistry, Department of Pedodontics, in Sivas, Turkey, between January 2007 and June 2012. MATERIALS AND METHODS: A total of 591 children (356 boys and 235 girls) with 1,287 injured teeth (394 primary and 893 permanent teeth) were included in the study. The children were evaluated in terms of gender, age, number of injured teeth, type of trauma, the interval between the traumatic event and time of seeking, and treatment procedures. RESULTS: The highest frequency of trauma occurred in the 12-14 year age group (14%). The most common type of injury was enamel-dentin fractures (58%) in primary teeth and complicated crown fractures (39%) in permanent teeth. Falls (30%) were the major cause of dental injury. Direct restoration (27%) without any endodontic treatment was the most common treatment procedure for permanent teeth. The most frequent treatment for primary teeth was examination and follow-up (42%). The upper central incisors (71%) were the mostly affected teeth in both primary and permanent teeth. Most dental trauma occurred in June and July (12%-8%). Only 63 children (11%) were referred to the clinic less than 30 minutes after trauma. CONCLUSION: Traumatic dental injury is considered a serious public health problems especially in children; parents and teachers should be informed on prevention and emergency management of traumatic dental injuries. In addition, the findings showed that initial treatment after dental trauma should be as quick as possible.