Özlem Malkondu

A Review on Biodentine, a Contemporary Dentine Replacement and Repair Material

Biodentine is a calcium-silicate based material that has drawn attention in recent years and has been advocated to be used in various clinical applications, such as root perforations, apexification, resorptions, retrograde fillings, pulp capping procedures, and dentine replacement. There has been considerable research performed on this material since its launching; however, there is scarce number of review articles that collates information and data obtained from these studies. Therefore, this review article was prepared to provide the reader with a general picture regarding the findings about various characteristics of the material. The results of a PubMed search were classified and presented along with some critical comments where necessary. The review initially focuses on various physical properties of the material with subheadings and continues with biocompatibility. Another section includes the review of studies on Biodentine as a vital pulp treatment material and the article is finalized with the summary of some case reports where the material has been used.

Effects of different silanes and acid concentrations on bond strength of brackets to porcelain surfaces

The aim of this study was to determine the optimum silane-coupling agent and the optimum concentration of acid agent when bonding to porcelain surfaces. Eighty deglazed feldspathic porcelain discs with a diameter of 10 mm and a thickness of 2 mm mounted in acrylic resin blocks were randomly divided into four groups. In groups 1 and 2, the porcelain surfaces were etched with 9.6 per cent hydrofluoric (HF) acid and in groups 3 and 4 with 5 per cent HF acid. In groups 1 and 3, the Dynalock maxillary central incisor brackets were bonded with Pulpdent silane and Unite bonding adhesive and in groups 2 and 4 with Reliance silane and Unite. Shear forces were applied to the samples using an Instron universal test machine. The non-parametric Kruskal-Wallis test was used to determine significant differences in bond strengths between the four groups and Dunns multiple comparison test to compare subgroups. The mean bond strengths and standard deviations of groups 1 to 4 were 5.51 +/- 1.19, 6.54 +/- 0.002, 4.55 +/- 1.93, and 6.39 +/- 0.45 MPa, respectively. Specimens bonded with Reliance showed a statistically significantly higher in vitro bond strength than those bonded with Pulpdent. The concentration of etching gels did not result in any statistically significant difference on the in vitro bond strength when evaluated separately.

Comparison of the fracture resistance of simulated immature permanent teeth using various canal filling materials and fiber posts

BACKGROUND   The purpose of this study was to compare the fracture resistances of immature teeth treated with MTA along with root canal obturation methods using AH Plus, MetaSEAL, MTA Fillapex sealers + lateral compaction technique, and Unicore quartz fiber posts. MATERIALS AND METHODS   Fifty single-rooted maxillary anterior teeth were divided into five groups. The crowns were dissected and root canals were enlarged. #6 Peeso reamers were allowed to protrude 1 mm. beyond the apex to simulate immature teeth. The apical 4-5 mm of each tooth was filled using Angelus white MTA. The remaining portions of canals were obturated as follows: Group 1: No backfilling (control), Group 2: AH Plus + gutta-percha, lateral compaction, Group 3: MetaSEAL + gutta-percha, lateral compaction, Group 4: MTA Fillapex + gutta-percha, lateral compaction, Group 5: UniCore Fiber posts luted using PermaFlo DC. The specimens were embedded into self-curing acrylic poured into identical cylinders which were mounted on a jig providing a 45° angle. A compressive load increasing at 1 mm min(-1) was applied and the maximum load at which fracture occurred was recorded. Statistical analysis was performed using Kruskal-Wallis and Dunns multiple tests. RESULTS   The highest fracture resistance was obtained with Group 5 (Fiber posts) whereas Group 4 (MTA Fillapex) yielded the lowest values. The mean fracture resistance value of Group 2 (AH Plus) was significantly higher than Group 4 (MTA Fillapex) (P = 0.001). The mean fracture value of Group 5 (Fiber posts) was significantly higher than Group 2 (AH Plus), Group 3 (MetaSEAL), and Group 4 (MTA Fillapex) (P = 0.02, 0.004, and 0.0001, respectively). CONCLUSION   Within the limitations of this study, UniCore quartz fiber posts provided the highest resistance. This methodology may specifically be advantageous for teeth with arrest of development at early stages, as these teeth are more susceptible to fracture owing to their excessively weak dentinal walls.

An overview of monolithic zirconia in dentistry

Abstract Zirconia restorations have been used successfully for years in dentistry owing to their biocompatibility and good mechanical properties. Because of their lack of translucency, zirconia cores are generally veneered with porcelain, which makes restorations weaker due to failure of the adhesion between the two materials. In recent years, all-ceramic zirconia restorations have been introduced in the dental sector with the intent to solve this problem. Besides the elimination of chipping, the reduced occlusal space requirement seems to be a clear advantage of monolithic zirconia restorations. However, scientific evidence is needed to recommend this relatively new application for clinical use. This mini-review discusses the current scientific literature on monolithic zirconia restorations. The results of in vitro studies suggested that monolithic zirconia may be the best choice for posterior fixed partial dentures in the presence of high occlusal loads and minimal occlusal restoration space. The results should be supported with much more in vitro and particularly in vivo studies to obtain a final conclusion.

The Effect of Prophylactic Polishing Pastes on Surface Roughness of Indirect Restorative Materials

The purpose of this study was to evaluate the influence of prophylactic polishing pastes (PPP; Detartrine (DT), Topex (TP)) on surface roughness (R a) of indirect composites (IRC; Tescera (TES), Gradia (GRD), and Estenia C&B (EST)), a glass ceramic (Empress 2 layering (E2)), and a leucite reinforced glass ceramic (Empress Esthetic (EE)) with two different (glazed (G); polished (P)) surface preparations. A total of 90 IRC and 120 ceramic discs, 8 mm in diameter and 2 mm thick, were prepared. E2 and EE specimens were randomly divided into two groups (n = 30). One group was glazed (GE2; GEE), while the other group was polished (PE2; PEE) the same as the IRCs. The specimens in each group were subsequently divided into three subgroups: control (C), DT, and TP. R a (μm) was evaluated with a profilometer. Data were analyzed by Kruskal Wallis, followed by the Dunns multiple comparison tests (P < 0.05). DT and TP resulted in significant surface roughening for TES, GRD, and EST, while no significant differences were detected between DT and TP (P > 0.05). PE2 and PEE were not affected by DT or TP (P > 0.05), while GE2 and GEE exhibited significant roughening after TP (P < 0.05). Surface roughness of IRCs and glazed ceramics can be affected by PPP applications.

Radiological study on mandibular ramus asymmetry in young population

BACKGROUND The aim of this study was to estimate the prevalence of ramus asymmetries related to age and gender in a young population and the influence of growth spurt on ramus asymmetry. MATERIALS AND METHODS The study consisted of 776 panoramic radiographs of individuals aged 9 to 21 years (335 males and 441 females). Individuals were divided into two groups with respect of linear growth spurt as age 12 in females and age 14 in males. The first group consisted of females aged between 9 and 11 and males between 9 and 13. The second group consisted of females aged between 12 and 21 and males between 14 and 21. Bilateral ramus heights on each radiograph were measured. A panoramic software programme was used to measure the ramus heights. Quantitative data was tested by Students t test. Qualitative data was tested by χ2 test. The intraclass correlation coefficient was calculated for the magnitude error of the measurement. RESULTS The mean of ramus asymmetry was found to be 2.90% ± 2.58%. Significant differences between the right and left ramus height ratios were observed (p < 0.01). There was a high prevalence (10.8%) of ramus asymmetry, which did not correlate with the age and gender of the patients. CONCLUSIONS This study revealed a high prevalence of ramus asymmetry in 9-21- -year-old population. Within the limitations of this study, it can be concluded that ramus asymmetry should be carefully evaluated in all ages for the potential relation with temporomandibular dysfunctions and also for orthodontic anomalies.

Prosthodontic Management of a Patient with Oligodontia: A Case Report

Abstract Oligodontia or severe hypodontia is a rare developmental dental anomaly which is described as congenital absence of 6 or more teeth excluding the third molars. In this case report, the treatment of a 31-yearold woman with congenital absence of 9 permanent teeth is described. The treatment with occlusal appliance and fixed a partial dentures ended up in functional and aesthetic results.