Introduction: To achieve a proper disinfection of the root canal system, besides many irrigant solutions, laser has become increasingly popular in recent years. Bacteria that penetrate deep in the dentine can be destroyed by laser up to 1150 µm. The aim of the study is to investigate and to compare the efficiency of conventional chemical disinfection using cleaning solutions - sodium hypochlorite (2%), citric acid (20%) - and the physical disinfection using a diode laser (940 nm, 1 W) in vitro using extracted teeth. Material and Methods: 23 intact, single rooted teeth were prepared and inoculated with Enterococcus Faecalis. Afterwards samples were taken from each group and placed on solid mediums. The following were applied to members of each group prior to sampling: 2% sodium hypochlorite, 20% citric acid and diode laser (940 nm, 1W). To evaluate the results, so that the bacterial strains on the medium could be counted, quenches were performed from 1/10 and 1/100 dilutions. Statistical analysis was performed using Kruskall-Wallis and unpaired T-test with a value of p>0.05. Results: Statistical analysis on the 3 groups (NaOCl, citric acid, and diode laser) showed significant differences between the counted remaining colonies after disinfection. Conclusions: The diode laser used for disinfection under the used settings is not effective enough, but as an adjuvant, associated with conventional irrigation effective disinfection can be obtained. Keywords: root canal, E. Faecalis, sodium hypochlorite, citric acid, diode laser

Hydrophilicity of elastomeric impression materials is a key property in producing an accurate impression in prosthodontic treatment. Aim: To study the hydrophilicity (wettability) of two different elastomeric impression materials in vitro by comparing the initial water contact angles on five materials during setting. Materials and methods: Vinyl polysiloxane VPS (Imprint 4 Light and Super Quick Heavy) and Vinyl polyether silicone VPES (EXA’lence Light Regular, Light Fast and Heavy Fast set) were used. The leveled material surface received 1-µl droplet of deionized water 15 seconds after dispensing the impression material. Contact angles were measured at 0, 30, 60, 90, 120, and 150 seconds using a drop shape analysis machine. The data were analyzed using repeated measures ANOVA with time as a within-subjects factor and material as a between-subjects factor (α=0.05). Results: All material had high contact angles at time 0 (T1). Imprint 4 had lower contact angles than EXA’lence at all times. There was a statistically significant difference in contact angles of all EXA’lence materials compared to Imprint 4 when not accounting for time (P .001). When time was factored in, there was no significant difference at T1 only (P = .08). There was no significant difference among the three EXA’lence materials (P > .990) at all-time points. However, there was a significant difference between Imprint 4 materials with Imprint 4 Super Quick Heavy having lower means than Imprint 4 Light (P = .001). This was true for all time points except T1. Conclusions: Despite the high contact angle values at time 0 (T1), both materials reached a significant hydrophilic level with Imprint 4 having drastically lower mean values. Keywords: Contact angle, elastomeric impression material, initial hydrophilicity, VPES, VPS.

Endodontic file fracture has traditionally been viewed as an undesirable event. However, recent evidence suggests that the incidence of fracture may be higher with rotary nickel-titanium (NiTi) files. Therefore, it is crucial for clinicians to be aware of the prevalence of file fracture and the underlying causes of this unfortunate occurrence. The removal of fractured files is technically challenging and time-consuming, making it essential to implement measures to prevent fracture whenever possible. Over the past decade, file manufacturers have introduced various modifications such as mechanical and heat processes to NiTi alloys to reduce the likelihood of file separation, though with varying degrees of success. The aim of this review is to explore the prevalence and causes of file fracture, and to assess the efficacy of the recommended prevention protocols. Furthermore, the review evaluates the effectiveness of alloy modifications in reducing the incidence of file fracture. The analysis reveals that much of the literature on file fracture is based on in vitro studies, which limits its clinical relevance. The reported incidence of NiTi file fracture is similar to that of stainless steel (SS) files; however, inconsistent methodologies make accurate comparison difficult. NiTi files are reported to fail primarily due to torsional overload and/or flexural fatigue, with fractures occurring most often in the apical third of the canal or due to improper use. Finally, factors such as operator skill, manufacturer modifications, and limiting file reuse have been shown to significantly reduce the incidence of fracture, highlighting the importance of a robust prevention strategy. Keywords: Root canal treatment, file fracture, endodontics, nickel-titanium, review.

EDITORIAL

Orthodontic treatment is elective but not without risks. Prospective patients need to be fully informed of their treatment options and understand the associated risks and benefits. Aim of the study: To assess the perception of Nigerian orthodontic patients regarding the consent and assent-giving process before orthodontic treatment. Material and Methods: A total of 349 patients from the University of Port Harcourt Teaching Hospital and Lagos University Teaching Hospital, who received orthodontic treatment between December 2023 and May 2024, participated in this study. A 21-item questionnaire was administered via Google Forms. The questionnaire contained demographic questions and items assessing knowledge, perception, and practice of consent in orthodontics. Data were analyzed using IBM SPSS Version 26, employing descriptive statistics (frequencies and percentages). Results: Of the 349 participants, 99 (28.4%) were male, and 250 (71.6%) were female, with a mean age of 23.43 ± 10.49 years. 88% of female and 91.9% of male participants had heard of consent before treatment. A total of 93.1% of participants gave consent, with 78.5% of these being verbal. Pain (45.6%) was the most commonly explained complication, while infection (6.9%) was the least. 92% of participants were satisfied with the consent process. Conclusion: Most Nigerian orthodontic patients are aware of the consent process and are generally satisfied with it. Orthodontists in Nigeria should prioritize obtaining written informed consent to ensure patient protection and avoid potential legal issues. Keywords: Elective, Consent, Orthodontic patients, Complications, Informed consent

We are currently seeing an increase in the number of patients seeking orthodontic treatment, many of whom are young adults. Besides the obvious advantages of orthodontic therapy, there are also some side effects that can be seen at the level of periodontal soft tissues, which can influence the final result. Aim of the study: The purpose of this study is to identify the main changes observed in the soft tissues during orthodontic treatment with fixed appliances (colour, size, position, texture of gingiva and shape of anterior interdental papillae), and to analyse them depending on individual clinical characteristics, gender and gingival phenotype. Material and Methods: 22 patients were included in this study – 12 women and 10 men, aged between 14 and 30 years, that presented to the Integrated Centre of Dental Medicine in Târgu Mureș, in the period 2019-2024, in search of orthodontic treatment. Results: The study found significant differences in gingival changes based on gender and gingival phenotype, with females showing more pronounced colour changes and gingival hypertrophy in the mandibular regions, and males exhibiting substantial gingival hypertrophy and colour changes, both in the frontal and lateral maxillary regions. Conclusions: This study shows gingival changes during orthodontic treatment that differ by gender and gingival phenotype. Thus, females with a thick gingival phenotype show distinct colour and size changes in the frontal mandibular region, whereas male patients tend to have more changes in the frontal and lateral maxillary regions, regardless of the gingival phenotype. Keywords: gingival changes, orthodontic treatment, gingival phenotype.

Abstract Introduction: One of the main elements of facial esthetics is represented by the smile. A harmonious proportion between the elements of facial esthetics is an important subject of interest in dentistry. Aim of the study: This research aims to evaluate the impact of the gummy smile on future dental practitioners. Materials and Methods: A survey containing 16 questions was designed to find out the students’ perceptions about the ideal smile and if the gingival smile is considered youthful or unpleasing. The impact on their self-esteem, their willingness to change the gummy smile or not, the nonsurgical and surgical methods of treatment were also evaluated. Results: 212 answers were recorded and analyzed. Nearly three quarters (70.3%) of the respondents believe that having a gummy smile is unesthetic, while only 29.3% considered it to be a sign of youth. Self-esteem can be affected by having a gingival smile, but, according to the results, most of the students (45.8%) said that their daily lives have not been affected by it, 40.6% said that in a small amount, 10.4% said that their self-assurance has been very affected and only 3.3% admitted that the gummy smile distressed their confidence. When asked if they were willing to correct their gingival smile, 51.4% were open to improving it while 48.6% would not change it. Conclusions: Among dentistry students, excessive showing of the gums is believed to be unesthetic rather than a sign of youthfulness. The respondents are generally not affected in their daily life by having a gummy smile. Education regarding the methods of correcting it still needs to be addressed amongst future dental practitioners.