Comparison of successful outcome of pit and fissure sealants bonded with etch-and-rinse adhesive and self-etch adhesive system.

BACKGROUND: Dental caries is one of the most common diseases around the world. The newly erupted permanent posterior teeth are at great risk due to the complex occlusal morphology of pits and fissures, infraocclusion and incomplete maturation of enamel. Pit and fissure sealants are the treatment of choice in such conditions. OBJECTIVES: To compare the successful outcome of pit and fissure sealants bonded with etch-and-rinse adhesive system and self-etch adhesive systems in newly erupted permanent first molars. METHODS: This randomized clinical trial was conducted at the Fatimah Jinnah Dental Hospital from June 2017 to May 2019. Children aged between 6 to 9 years who fulfilled the inclusion criteria were recruited for this study after parents' consent. Patients were randomly divided into two groups by the lottery method. Thirty patients with 60 first molar teeth in Group A were treated with etch-and-rinse adhesive system, while the other thirty patients with 60 first molar teeth in Group B were treated with self-etch adhesive system. After adhesive placement, all children received the same fissure sealants in newly erupted maxillary and mandibular permanent first molar. Each group was clinically evaluated at 6 and 12 months follow-up visit. Modified United States Public Health Service (USPHS) criteria were used for direct clinical evaluation of successful outcomes such as sealant retention and marginal discoloration. RESULTS: Successful outcome was statistically significant in Group B compared to Group A (60% vs. 30% p= 0.020) at 12 months follow-up. Stratification analysis was performed with respect to age in which a successful outcome was not significant (p= 0.43) between groups for 6 to 7 years of age, while it was significant (p= 0.012) between groups in 8 to 9 years of age children. CONCLUSION: Self-etch adhesive system is better than etch-and-rinse adhesive system in terms of long-term sealant retention. In addition, the bonding procedure is simple with relatively short clinical application time therefore it would offer great benefit to clinicians in treating pediatric patients.

Influence of the Silver Content on Mechanical Properties of Ti-Cu-Ag Thin Films.

In this work, the ternary titanium, copper, and silver (Ti-Cu-Ag) system is investigated as a potential candidate for the production of mechanically robust biomedical thin films. The coatings are produced by physical vapor deposition-magnetron sputtering (MS-PVD). The composite thin films are deposited on a silicon (100) substrate. The ratio between Ti and Cu was approximately kept one, with the variation of the Ag content between 10 and 35 at.%, while the power on the targets is changed during each deposition to get the desired Ag content. Thin film characterization is performed by X-ray diffraction (XRD), nanoindentation (modulus and hardness), to quantitatively evaluate the scratch adhesion, and atomic force microscopy to determine the surface topography. The residual stresses are measured by focused ion beam and digital image correlation method (FIB-DIC). The produced Ti-Cu-Ag thin films appear to be smooth, uniformly thick, and exhibit amorphous structure for the Ag contents lower than 25 at.%, with a transition to partially crystalline structure for higher Ag concentrations. The Ti-Cu control film shows higher values of 124.5 GPa and 7.85 GPa for modulus and hardness, respectively. There is a clear trend of continuous decrease in the modulus and hardness with the increase of Ag content, as lowest value of 105.5 GPa and 6 GPa for 35 at.% Ag containing thin films. In particular, a transition from the compressive (-36.5 MPa) to tensile residual stresses between 229 MPa and 288 MPa are observed with an increasing Ag content. The obtained results suggest that the Ag concentration should not exceed 25 at.%, in order to avoid an excessive reduction of the modulus and hardness with maintaining (at the same time) the potential for an increase of the antibacterial properties. In summary, Ti-Cu-Ag thin films shows characteristic mechanical properties that can be used to improve the properties of biomedical implants such as Ti-alloys and stainless steel.

Replacement of resin-based composite restorations in permanent teeth.

OBJECTIVE: To determine the reasons for replacement of composite resin restorations and evaluate the association between the reasons for replacement of restorations with gender, duration of failure and different class of cavities. STUDY DESIGN: Cross-sectional study. PLACE AND DURATION OF STUDY: Operative Department of Fatima Jinnah Dental Hospital, Karachi, from January to May 2009. METHODOLOGY: Patients were selected randomly who had presented with post restoration complaint after composite filling. Specially designed proformas were used to get the information such as the name of the patient, age, gender, teeth in need for replacement of restorations, age of the replaced restorations, and the reasons for replacement. The criteria for replacement of composite restorations were secondary caries, discoloration, improper proximal contact, fractured restoration and gingival irritation due to overhang. The significance of results was obtained by applying chi-square test. RESULTS: A total of 413 patients ranging in age from 17 to 63 years were examined; 263 were males while 150 were females. Secondary caries (52.3%) was the most frequent reason for replacement of restorations in permanent teeth followed by discoloration (16.9%) and fracture of fillings (12.6%). Chi-square test shows significant relationship between gender and reasons for replacement (p < 0.001). Highly significant difference was found between different class of cavities and reasons for replacement of composite fillings (p < 0.001). The median longevity of the replaced composite restorations was about 3 years. CONCLUSION: Secondary caries was the most common reason for replacement of composite fillings. The median longevity in this sample was calculated to be 3.0 years.

Prospective evaluation of the systemic inflammatory marker C-reactive protein in patients with end-stage periodontitis getting teeth replaced with dental implants: a pilot investigation.

OBJECTIVES: Serum C-reactive protein (CRP) has been shown to be a risk predictor for cardiovascular disease. Periodontal treatment reduces elevated CRP levels. The aim of this pilot investigation was to evaluate if dental implants placed after extractions in patients with end-stage periodontitis affect the serum CRP levels. MATERIAL AND METHODS: Serum CRP levels in 10 subjects with end-stage periodontitis were measured prior to tooth extraction and placement of dental implants, and at 3-month intervals for a year post-operatively. Univariate repeated measures analysis of variance was used to estimate and test the changes in CRP levels over time. RESULTS: Mean CRP levels decreased significantly following tooth extraction and replacement with dental implants from 3.45 to 1.55 mg/dl after 12 months (P < 0.01). Six-, 9-, and 12-month post-implant placement mean CRP values were statistically significantly different from the mean pre-operative CRP value (P < 0.01). CONCLUSIONS: The pilot data suggest that extraction of advanced periodontally involved teeth and their replacement with dental implants lead to a decrease in CRP levels, and dental implant placement does not change the lowered CRP levels over a 12-month period.

Success rate of resin bonded restorative dentistry bridges.

OBJECTIVE: To assess the success rate of resin bonded bridges. DESIGN: A descriptive cross-sectional study. PLACE AND DURATION OF STUDY: Fatima Jinnah Dental College Hospital, Karachi between August 1998 and August 2002. SUBJECTS AND METHODS: Seventy resin bonded bridges fitted in 60 patients were clinically assessed for debonding. The inclusion criteria included minimal reduction of teeth with minimal occlusal contacts. Patients were excluded if teeth had a large discrepancy of space and heavy occlusion. The retainers were designed self retentive and covered the maximum tooth surface lingually and proximally. Impressions were taken and resin bonded bridges were fabricated and bonded. Information regarding the patient's data, bonding and debonding was collected on a proforma and was analysed using SPSS version 10.0. RESULTS: Seventy resin-bonded bridges had been in place for an average of 33 months. The results showed a 94.3% success rate. Statistically significant results were found between anterior bridges and posterior bridges for bonding status (p< 0.05). Results were not significant where maxillary versus mandibular bridges were compared for bonding status. (p>0.05). CONCLUSION: Resin bonded bridges achieved a high level of clinical success in the study.