The Influence of Nickel-Titanium (Ni-Ti) Rotary Instrument Systems on Debris and Smear Layer Formation in Endodontic Procedures: An In Vitro Scanning Electron Microscopy Study.

Background Successful endodontic treatment relies on the effective removal of debris and the prevention of smear layer formation within the root canals. The choice of nickel-titanium (Ni-Ti) rotary instrument systems can significantly impact these outcomes. Aim This study aims to evaluate and compare the debris and smear layer formation in root canals of extracted mandibular second premolar teeth following instrumentation with the ProTaper Universal (Dentsply Sirona, Charlotte, NC) (Group II), Twisted File (Kerr Endodontics, Gilbert, AZ) (Group III), and XP Endo (FKG Dentaire, La Chaux-de-Fonds, Switzerland) (Group IV) Ni-Ti rotary instrument systems. Methods In this in vitro study, 60 extracted mandibular second premolar teeth were randomly divided into four groups, each containing 15 teeth. Group I served as the control with no instrumentation. Groups II, III, and IV were instrumented with the ProTaper Universal rotary file, the Twisted File, and the XP Endo file systems, respectively. Debris and smear layer formation were evaluated through scanning electron microscopy (SEM), and photomicrographs were scored using a standardized index. Results Group II (ProTaper) exhibited the highest mean debris and smear layer scores, with values of 3.50 and 2.70, respectively. Group IV (XP Endo) demonstrated the least debris and smear layer formation, with mean scores of 2.65 and 2.08, respectively. Statistical analysis confirmed significant differences among the groups for both debris and smear layer formation. Conclusion The results highlight the practical importance of selecting appropriate Ni-Ti rotary instrument systems to minimize debris and smear layer formation during endodontic procedures. The XP Endo file system showed promise as a favorable choice in this regard, but further clinical research is needed to validate these findings.

A Look Into the Cytotoxicity of Composite Fillings: Friend or Foe?

Dental resin composites are widely used restorative materials in dentistry for the treatment of carious and non-carious lesions as well as pit and fissure sealants, cavity liners, and endodontic sealers. They consist of two parts: an organic resin matrix and an inorganic/organic filler. The organic resin matrix phase is made up of multifunctional monomers and light-sensitive initiators, while the inorganic/organic filler phase is made up of micro/nano-sized fillers that primarily serve as reinforcement. Despite being a very promising dental material, its monomeric component has some drawbacks. It is well known for leaching out during incomplete polymerization, which can result in cytotoxicity. Bis-GMA (bisphenol A-glycidyl methacrylate) is the most cytotoxic of all monomeric components that exhibit synthetic estrogenic effects. The purpose of this article is to assess the cytotoxic effects of dental composite, understand the possible mechanism behind them, and explore ways to screen for and reduce this harmful effect, as well as shed light on its future prospects.

Exploring the Biological Width in Dentistry: A Comprehensive Narrative Review.

Biological width (BW) is the distance established from the junctional epithelium and connective tissue attachment to the root surface of a tooth. It acts as a natural seal protecting the tooth from infections and diseases. The normal dimension of it is 2.04 mm on average. A periodontal probe is used to determine BW in routine clinical practice. Various methods are available for the determination of BW. A diagnosis of BW violation is asserted when the distance is found to be less than 2 mm at single or multiple locations. Gingival health is of utmost importance when considering the long-term health of the tooth as well as any restoration. A plethora of BW violations can lead to a myriad of complications, which are discussed briefly in this article. The article also aims to highlight BW in relation to restorative margins and implants and its clinical assessment as well as shed light on the procedure that can be employed to correct BW violations in dental practice.

A Comparative Study to Evaluate the Anesthetic Efficacy of Buffered Versus Non-buffered 2% Lidocaine During Inferior Alveolar Nerve Block.

BACKGROUND: The study aimed to compare the clinical efficacy, safety, and acceptability of buffered lidocaine (8.4% sodium bicarbonate and 2% lidocaine with 1:80,000 adrenaline) versus non-buffered lidocaine (2% lidocaine with 1:80,000 adrenaline) during inferior alveolar nerve block. MATERIALS AND METHODS: Fifty patients who required bilateral extractions in a single arch were included in this study. One hundred extractions were carried out, and all of the patients had nerve blocks during the procedure. We also took note of the patient's pain level as measured on a visual analog scale, as well as the start of the action, duration of postoperative analgesia, and occurrence of any problems. The duration of anesthesia was assessed by the feeling of numbness and the first sign of pain. RESULT: All the patients in both study groups reported subjective numbness of the lips and tongue. The depth of anesthesia was evaluated by pain and comfort during the procedure with a visual analog scale and showed no significant difference between the two groups. The onset of action for the pterygomandibular nerve block was 1.240.31 minutes (buffered) and 1.710.51 minutes (non-buffered). When compared, the duration of anesthesia was 327.18102.98 minutes (buffered) and 129.0826.85 minutes (non-buffered). CONCLUSION: This study concludes that the buffered solution has a faster onset of action than the non-buffered solution. Both solutions exhibit similar intraoperative efficacy. The duration of postoperative anesthesia was prolonged with buffering. Buffering also reduced pain scores during the early postoperative period.

Efficacy of Rotary and Hand Instrument in removing Gutta-percha and Sealer from Root Canals of Endodontically Treated Teeth.

AIM: One of the common dental procedures employed these days in patients with irreversible pulpitis is root canal therapy. In retreatment cases, it is necessary for complete removal of obturate gutta-percha (GP) from obturate root canal system. Various methods and techniques are available these days for this purpose. This study was aimed to assess the efficacy of D-RaCe files, ProTaper retreatment files, Mtwo retreatment files, and manual Hedstrom files (H-files) in removing filling materials from the root canals of the endodontically treated teeth. MATERIALS AND METHODS: The present study included comparative evaluation of efficacy of nickel-titanium (NiTi) retreatment instruments and H-files in removing GP and sealer from root canals. All the samples were randomly and broadly divided into four study groups based on the instrumentation technique for removing the root canal fillings. Evaluation of the results was done based on operating time and remaining root canal filling material. Stereomicroscopic evaluation of the samples was done at 8* magnification. RESULTS: All the results were assessed and analyzed by Statistical Package for the Social Sciences (SPSS) software. Least quantity of filling material was left by ProTaper retreatment files. When put together in decreasing order, the efficacy of different study groups, in terms of mean time taken for retreatment, was found to be as follows: D-RaCe > ProTaper Retreatment > Mtwo Retreatment > H-file. CONCLUSION: No single technique can completely remove obturating fillings from the root canals of endodontically treated teeth. However, rotary instruments are better in comparison with hand instruments for removing the GP from obturate root canals. CLINICAL SIGNIFICANCE: ProTaper retreatment files and D-RaCe files are recommended over other instrument systems in terms of quality for managing retreatment root canal cases.

Palatal Rugae Patterns as a Bioindicator for Forensic Identification in Kodava and Tibetan Populations of India.

BACKGROUND: Palatal rugae are distinct to each individual and are highly specific to each individual as their fingerprints. Rugae pattern are specific to different racial groups making it convenient for population identification. Palatal rugae retain their shape throughout life and hence can be useful as an identification tool. The present study aimed at analyzing the differences in rugae pattern among Kodavas and Tibetan populations of Coorg, India and to examine if there was a difference in the rugae pattern between males and females within each group. MATERIALS AND METHODS: The study comprised of 30 participants between 18 and 30 years of age, equally distributed between genders from each group. Examination of maxillary cast after tracing the rugae patterns was carried out. Rugae pattern was classified as "straight," "wavy," "curved," "circular" and "unification." Statistical analysis was done using SPSS 16 software. Non-parametric Mann-Whitney test was used for pairwise comparison of two populations. Mann-Whitney two-tailed test was used to test the difference between males and females. RESULTS: Results showed that wavy pattern was highest for both the groups. Circular rugae were totally absent in both the groups. There was a significant difference between Kodavas (mean = 1.000) and Tibetans (mean = 0.13) for unification pattern (P = 0.001). CONCLUSION: Palatal rugae patterns can be used as a bioindicator for human identification.