ABSTRACT
Remaining root dentin thickness plays a key role in the longevity of endodontically treated teeth. Purpose: The aim of this study was to compare the root canal wall thickness in the danger zones of mandibular incisors before and after their instrumentation with two different NiTi rotary systems by means of CBCT. Methodology: Thirty lower incisors of patients aged 45 – 55 years underwent primary endodontic treatment with two NiTi files systems: ProTaper Universal and WaveOne Gold. The changes of the root canal thickness in the danger zones of the incisors were investigated by two CBCT scans – one at the beginning of the experiment and the other after the shaping of the root canals. Results: Shaping of the root canals of lower incisors with the two NiTi systems significantly decreased the mesio-distal root dentin thickness in all root canal levels when compared with the baseline values (p≤0.001). NiTi files from both experimental groups removed substantially more root dentin in the coronal portion of the root than in the apical (p<0.05). The intergroup comparison between the two tested NiTi systems revealed no statistically significant difference in their performance at the three observation levels (p>0.05). Conclusions: Both NiTi systems performed equally and removed dentin more aggressively in the coronal portion of the root. Further clinical experiments are necessary to find the minimally invasive endodontic systems for an optimal preservation of root dentin in the danger zones of mandibular incisors.

ABSTRACT
Dens invaginatus is a tooth anomaly described by a development of an infolding structure into the root canal. Its treatment is challenging because of the difficulties observed in different types of this malformation. An early diagnosis face to crown morphologic abnormalities is the most effective mean of treatment. This paper focuses on importance of the clinical and radiological examination of Dens invagination and describes different therapeutic approach through several cases.

ABSTRACT
Background: The orbital aperture morphometry can be considered as a valuable tool in gender determination since orbit possesses resistance to damage and disintegration processes. Aim and Objective: The aim and objective of this study was to evaluate the orbital aperture dimensions in nalgonda population and verify their relationship with gender. Materials and Methods: The present retrospective study was conducted to evaluate the morphometric dimensions of orbital aperture seen on digital orthopantomogram taken using PLANMECA digital machine and ROMEXIS software. The height and width of the orbits were measured using measuring tools in the accompanying software. Data were analyzed using IBM SPSS Statistics for Windows, Version 23.0. Armonk, NY: IBM Corp. Results: Linear measurements such as orbital height and orbital width, were significantly greater in males than females in the Nalgonda population with P < 0.001. The present study found 85.6% accuracy after subjecting the obtained value to discriminant function analysis. Conclusion: The discriminant scores greater than 1.5 value indicate the sample as male and scores lesser than 1.5 value indicate the sample as female. Therefore, orbital aperture measurements can be used for gender determination in human identification.

ABSTRACT
Considering the issue of recurrent apthous ulcers affecting individuals worldwide, knowledge of the significant associating triggering factor is an essential tool, which can be used to figure out the most challenging factor behind that can be further controlled or avoided in an effort to reduce the chance of re occurrence by taking proper precautions. This paper evaluates the association of recurrent apthous ulcers with stress and other possible triggering factors such as Allergy and diet, among individuals in the northern part of Nigeria, represented by 4 states which include, Kano, Zamfara, Maiduguri and Katsina states respectively. Age, occupation, gender, history of re occurrence, site of occurrence in the oral cavity, number, duration of ulcers and nature of healing were highly considered in the study. 75 structured questionnaires were distributed among individuals of both genders, out of which 71 were retrieved and 4 left unanswered. The research methodology uses both correlation and descriptive statistical analysis. Following data analysis, using correlation table, there is weak correlation between Apthous ulcer and stress with .012 covariance. The results were analyzed using SPSS 25.0 VERSION and displayed in the form of Graph and tables. In conclusion, necessary preventive measures were outlined and further research recommendation is suggested in light of creating more awareness about the effects and importance of prevention to be considered by the society.

ABSTRACT
The complex anatomy of oval-shaped root canals presents a major challenge for secondary endodontic retreatment. The positive outcome of the retreatment depends on the proper cleaning and reshaping of the root canal space. Despite the use of various retreatment techniques and the improvement of additional protocols, none of them has yet succeeded in cleaning the entire root canal from filling residue. The untouched irregularities of the oval-shaped canals represent a reservoir for debris and microorganisms that are the main cause of endodontic treatment failure or delayed healing process. Further research should be done to improve the retreatment protocols of oval shaped canals. The aim of this review was to observe the articles investigating the efficacy for retreatment of oval-shaped root canals in the last 10 years.