Dental Hypotheses
Volume:14 Issue: 3, Jul-Sep 2023

We aimed to use polymerase chain reaction (PCR) on genomic deoxyribonucleic acid (DNA) to detect the Db allele and the rs2923234 and rs1049112 single nucleotide polymorphisms (SNPs) of the salivary acidic proline-rich proteins (PRPs) to determine their relationship with dental caries in young children.

DNA was extracted from saliva samples of preschool children aged 3 to 5 years. PCR primers designed around exon 3 of the PRH1 locus yielded a 416-base product representing Db for gel electrophoresis and a 519-base product representing the rs2923234 and rs1049112 SNPs for Sanger sequencing. The data were analyzed using a logistic regression model and a multilayer perceptron artificial neural network.

Forty children with severe caries and 40 caries-free children completed the study. The frequency of the Db gene was 16.3% in the entire study group. The rs2923234 SNP was a marginally significant (P=0.053) predictor for the dependent variable (caries-free or severe caries). However, the rs1049112 (P=0.407) and the Db allele (P=0.442) were not significant predictors.

The rs29232334 SNP could be considered a potential genetic predictor for caries susceptibility.

We aimed to compare the salivary level of malondialdehyde (MDA) in localized periodontitis versus generalized periodontitis.

Nineteen healthy participants, 35 cases of generalized periodontitis, and 36 cases of localized periodontitis included in the study. The enzyme-linked immunosorbent (ELISA) assay was used to blindly quantify the amounts of MDA in saliva. Data analyzed using one-way ANOVA and Tukey’s post hoc test via R software.

Ninety subjects completed the study. There was a statistically significant difference among study groups (P < 0.001). The Tukey’s post hoc test showed a statistically significant difference for all pairwise compressions (P < 0.001)

The salivary levels of MDA increase in periodontitis patients. Within limitations of this crosssectional study, it could be concluded that salivary MDA levels may possibly be a potential biomarker to examine oxidative stress in periodontal disease.

In this study, we aimed to evaluate the impact of ultraconservative and traditional endodontic access cavities on the total percentage increase in the surface area of root canals.

Endodontic instrumentation was performed on 30 simulated maxillary first premolars with two roots using traditional and ultraconservative access cavities via ProTaper Next rotary files. The pre- and postinstrumentation photographs of the root canals were analyzed blindly using Fiji software to determine the percentage increase in surface area.

A significant increase in the surface area of the root canal was observed with an ultraconservative endodontic access cavity compared to a traditional access cavity. The difference between the palatal and buccal roots was not significant, but there was a significant difference among the coronal, middle, and apical thirds of the root canal.

Ultraconservative access cavities have a significant impact on the increase in surface area of the root canal after instrumentation.

The objective of the study was to assess coronal leakage following root canal treatment utilizing four Micro Mega rotary nickel–titanium files, specifically One shape, Two shape (s1), Two shape (s2), and Revo-S, by means of dye penetration analysis using a stereomicroscope set at 20× magnification.

Fifty human lower premolar teeth that were extracted for orthodontic reasons were included in the study, excluding teeth with cracks, caries, severe curvature (<25°), or root resorption. The teeth were randomly assigned to five groups using www.random.org, and standard endodontic treatments were performed as per the manufacturer’s instructions using Micro Mega One shape, Two shape (s1), Two shape (s2), and Revo-S rotary nickel–titanium systems. To measure dye penetration, the teeth were immersed in a 2% methylene blue dye solution for approximately 24 hours and then axially split using a diamond sectioning disc, with measurements taken using a stereomicroscope.

The study groups showed statistically significant differences (P < 0.001), and all pairwise comparisons were found to be significantly different according to the post hoc test (P < 0.001).

Our results showed that various rotary file designs significantly affect coronal leakage.

The objective of this study was to evaluate the impact of chitosan nanoparticles’ pretreatment of dentin surface on the macro shear bond strength of resin composite, both immediately and over an extended period.

Thirty caries-free, unrestored human premolars were randomly assigned to six study groups. The dentin surface of the intervention groups underwent pretreatment with 0.2% chitosan and 0.05% NaF solutions for 1 minute. A standard etch-and-rinse adhesive procedure was performed for all the study groups. After 24 hours, half of the specimens underwent a macro shear bond strength test at a crosshead speed of 1 mm/min, whereas the other specimens underwent the same procedure after 300 thermal cycles between 5 and 55°C with a 30-second dwell time in the thermocycling device.

The study found that the type of dentin surface treatment agents did not significantly affect the shear bond strength (P=0.52). However, there were statistically significant differences between immediate and prolonged shear bond strength in the chitosan (P < 0.01) and the control groups (P =0.005). On the other hand, there were no significant differences between the immediate and prolonged shear bond strength in the NaF group (P =0.997).

Dentin pretreatment with 0.2% chitosan solution did not significantly affect the shear bond strength of the etch-and-rinse adhesive system. Pretreatment with NaF maintained the shear bond strength of the adhesive to dentin after 300 thermal cycles.

Introduction How to save more bone for the teeth of patients with chronic periapical periodontitis with intact or small defects of the labiobuccal cortical plate in the periapical surgeries is a problem that many dentists are concerned about. The Hypothesis: We came up with a new strategy for periapical surgery by designing a modified osteotomy and fenestration method, which we named the “guiding groove” method. There are two ways to achieve this, one is to perform guided groove positioning under CBCT dynamic navigation, and the other is to design a guide plate that marks the position and direction of the guided groove based on CBCT data before surgery. Evaluation of the Hypothesis: The existence of the “guiding groove” locks in the angle and direction of the ultrasonic root end preparation and retrofilling apparatus, which not only minimizes the deviation of the root canal but also preserves more cortical plate on the labial and buccal sides of the teeth and thus improves the efficiency of treatment. This hypothesis has certain limitations. Firstly, the technical sensitivity of the operation is high, and proficiency in CBCT dynamic navigation technology is required. The accuracy requirements for navigation equipment are also relatively high. It will also increase the patient’s exposure to X-rays. For the guide plate designed before surgery that has already marked the position of the guide groove, it can only accurately avoid the deviation of the operating instrument in the proximal and distal directions, and it is difficult to avoid the deviation of the instrument in the buccal and lingual directions.

Dental implants have revolutionized modern dentistry, providing an effective solution for the replacement of missing teeth. However, the long-term success of dental implants can be compromised by the development of biofilms on their surfaces. Biofilms are complex microbial communities embedded in a self-produced extracellular matrix, and they play a crucial role in the pathogenesis of various oral diseases, including peri-implantitis. This article aims to explore the relationship between dental implant roughness and biofilm formation, shedding light on the mechanisms by which surface characteristics influence microbial colonization and subsequent biofilm development. Understanding these interactions will aid in the development of improved implant surfaces and preventive strategies to enhance longterm implant success.