Evaluation of Pre- and Post-loading Peri-implant Crestal Bone Levels Using Cone-beam Computed Tomography: An In Vivo Study.

AIM: To evaluate the buccal, lingual, mesial, and distal crestal bone around implant using CBCT analysis having buccal crestal bone width of 1 mm after placement of implant and after 3 months of loading. MATERIALS AND METHODS: Twenty-five patients between 18 and 60 years of age with adequate bone width and height were selected for this in-vivo study with single or multiple missing teeth. Surgical stent was fabricated for all of them by using self-cure acrylic resin for selection of implant according to the availability of bone, and gutta-percha was used as radio-opaque marker to locate the implant site. After proper analysis, in the first stage surgery, implants were placed. After 3 months to this, the second stage surgery was performed followed by elastomeric impression for porcelain fused to metal prosthesis fabrication. The buccal, lingual, mesial, and distal bone width and height were evaluated by using cone-beam computed tomography (CBCT). CBCT was standardized in terms of FOV (field of vision), slice thickness, and interval. After 3 months of loading, CBCT was taken to evaluate the alteration in the crestal bone around implants. Pre- and post-loading, crestal bone on four locations was measured by using CBCT software. RESULTS: There is significant bone loss at all the locations, buccal, lingual, mesial, and distal, at the time of placement and after 3 months of loading of implant (p <0.05). The mean difference of 0.840, 0.933, 0.840, and 0.380 at buccal, lingual, mesial, and distal locations, respectively, shows statistically significant difference in pre- and post-values of mean bone loss at buccal, lingual, mesial, and distal positions. Pre-loading bone loss was maximum in the distal surface, while post-loading bone loss was maximum in the buccal surface. CONCLUSION: From this study, it is concluded that although crestal bone loss was higher before implant placement, there was significant alteration in crestal bone even after loading of implant. CLINICAL SIGNIFICANCE: It is widely accepted that the bone loss around the implant crest module is multidisciplinary in nature. Long-term preservation of the crestal bone is a paramount for successfully functioning of dental implants. Preserving crestal bone will help in dissipating the functional load. With proper treatment planning by the practitioner, this technical contribution to the crestal bone loss can be minimized and long-term survival of dental implants can be achieved.

Impact of recycling on the mechanical properties of nickel-titanium alloy wires and the efficacy of their reuse after cold sterilization.

OBJECTIVE: This study aimed to assess the feasibility of reusing nickel-titanium (NiTi) alloy wires after 6 weeks of intraoral use by evaluating the changes in the load-deflection properties and surface characterization of these alloy wires after cold sterilization by immersion in 2% of acidic glutaraldehyde for 10 h. MATERIAL AND METHODS: Twenty wires each in three groups of G1-as-received wires (ARW), G2-unsterilized used wires, and G3-sterilized used wires (SUW) were tested by the three-point bending test and scanning electron microscopy (SEM). The data were subjected to statistics, one-way analysis of variance, and Bonferroni posthoc test for comparison. RESULTS: Recycling of NiTi wires produced statistically insignificant changes in both the loading and unloading properties of the wires. The forces needed to twist the used wires, that is, G2-(UUW) and G3-(SUW) were lower than G1-(ARW), suggesting lowering of the stiffness of the wires. Superelasticity is well-maintained by G2-(UUW) and G3-(SUW) although there is an insignificant lowering of the forces exerted by them during loading and unloading. SEM demonstrated no increase in the pitting of surfaces in both G2-(UUW) and G3-(SUW); multiple areas were seen to be more smoothened over G2-(UUW) and G3-(SUW) NiTi wires surfaces. CONCLUSION: The findings of this study support the reuse of NiTi wires after 6 weeks of use in oral conditions followed by cold sterilization by immersion in 2% acidic glutaraldehyde for 10 h.

Prevalence of Tooth Decay and Associated Factors Among Ethiopian Patients

Abstract Objective: To assess the prevalence of tooth decay and it's associated factors among the age group of 15-20 years old visiting Ayder Comprehensive Specialized Hospital. Material and Methods: An epidemiological cross-sectional descriptive study was conducted among 384 subjects aged 15-20 years. A closed-ended questionnaire, according to the World Health Organization methodology was used to collect the data. The subjects were examined for the presence of tooth decay using the DMFT Index. One examiner was trained and standardized using a Kappa test (K=0.90). To test the differences in the DMF-T index related to socioeconomic variables, the Chi-square and the Mann-Whitney tests were employed. For all tests, the level of significance was set at p≤0.05 with 95% Confidence level. Results: The magnitude of tooth decay among study participants was 57.8%. The mean decayed, missed and filled was 1.26 and prevalence was higher in males (34.1%). Poor oral hygiene practice was strongly associated factor with tooth decay. 56.2% of visitors from the urban area were mainly affected by tooth decay. Conclusion: Tooth decay is highly prevalent among visitors between15-20 years of age. Tooth brushing habit, residency, and consumption of sugary food and drinks were significantly associated with the occurrence of tooth decay. Early diagnosis and prompt treatment can prevent further damage.

Amelogenin Gene - The Pioneer in Gender Determination from Forensic Dental Samples.

INTRODUCTION: In the event of any mass fatality incident, DNA analysis plays a vital role in disaster victim identification. Teeth are one of the most resistant structures in the human body that resist decomposition hence making them prime choice for extracting DNA for identification of individuals. Polymerase Chain Reaction (PCR) analysis that target regions of Amelogenin gene have become the method of choice for sex determination of biological samples. AIM: Determining the sex of a given DNA sample from either dental pulp or dentin of tooth and help in identification of missing persons and disaster victims. MATERIALS AND METHODS: In our study 50 teeth samples were studied and they were subjected to various environmental conditions along with freshly extracted teeth taken as control for duration of one month and three months. Pulpal tissue was retrieved from the teeth specimens by access opening of root canals and for incinerated samples, the specimens were crushed. From the DNA that was extracted from the dental pulp sample Amelogenin gene locus was used for sex determination by amplifying a segment of X-Y homologous gene locus through PCR analysis. RESULTS: ANOVA test and t-test proved to be statistically significant and 100% retrieval rate was observed in samples. CONCLUSION: Pulpal tissue along with degenerating odontoblastic processes yield sufficient amount of DNA for gender determination when subjected to various forensic conditions with maximum accuracy.

Role of Chemically Modified Tetracyclines in the Management of Periodontal Diseases: A Review.

Researchers have found that Chemically Modified Tetracyclines (CMTs) act through multiple mechanisms, affecting several parameters of osteoclast function and consequently inhibit bone resorption by altering intracellular calcium concentration and interacting with the putative calcium receptor; decreasing ruffled border area; diminishing acid production; diminishing the secretion of lysosomal cysteine proteinases (cathepsins); inducing cell retraction by affecting podosomes; inhibiting osteoclast gelatinase activity; selectively inhibiting osteoclast ontogeny or development; and inducing apoptosis or programmed cell death of osteoclasts. Thus TCs/CMTs, as anti-resorptive drugs, may act similarly to bisphosphonates and primarily affect osteoclast function. Researchers have evaluated the influence of various chemically modified tetracyclines from CMT-1 to CMT-10 on collagenases and gelatinases through in vitro or animal studies and concluded that all the CMTs except CMT-5 inhibited periodontal breakdown through MMP inhibition in the following order of efficacy: CMT-8>CMT-1>CMT-3>CMT-4>CMT-7. Thus the non-antimicrobial actions of the chemically modified analogues of tetracyclines have shown remarkably better mechanisms to those of agents with established anti-inflammatory/antioxidant potential. These findings clarify the multi-faceted actions of tetracyclines which are unique amongst antimicrobials, with therapeutic applications in periodontal and metabolic diseases. Hence, the present review describes the role of chemically modified tetracyclines in the management of periodontal diseases.

Evaluation of effectiveness of hyaluronic acid in combination with bioresorbable membrane (poly lactic acid-poly glycolic acid) for the treatment of infrabony defects in humans: A clinical and radiographic study.

BACKGROUND: The combination of biomaterials, bone graft substitutes along with guided tissue regeneration (GTR) has been shown to be an effective modality of periodontal regenerative therapy for infrabony defects. Therefore, the present randomized controlled clinical study was undertaken to evaluate the effectiveness of hyaluronic acid (HA) in combination with bioresorbable membrane for the treatment of human infrabony defects. MATERIALS AND METHODS: Twenty four infrabony defects in 20 systemically healthy patients were randomly assigned to test (HA in combination with bioresorbable membrane) and control (bioresorbable membrane alone) treatment groups. Probing pocket depth (PPD), relative attachment level, and relative gingival margin level were measured with a computerized Florida disc probe at baseline and at 6 months follow-up. Radiographic measurements were also evaluated at baseline and at 6 months of postsurgery. RESULTS: At 6 months, the mean reduction in PPD in test group and control group was 4.52 mm and 2.97 mm, respectively. Significantly higher clinical attachment level with a gain of 2.20 mm was found in the test group as compared to control group. In addition, statistically significant greater reduction of radiographic defect depth was observed in the test group. CONCLUSION: Regenerative approach using hyaloss in combination with GTR for the treatment of human infrabony defects resulted in a significant added benefit in terms of CAL gains, PPD reductions and radiographic defect fill, as well as LBG, compared to the GTR alone.