Linear and volumetric shrinkage displacements of resin composite restorations with and without debonding.

The study aimed to compare shrinkage displacements of fully and partially bonded resin composite restorations (RCRs). Two groups (n=5) Class-I RCR evaluated: Group 1 (G1) fully bonded and Group 2 (G2) debonded at the floor. Experimental results were compared with predictions from simple theory and finite element analysis (FEA). The experimental linear surface displacement (LSD) was G1 62.5±5.2 µm and G2 32.8±4.0 µm. Theoretically-predicted LSD for G1 60.1±7.4 µm and G2 31.3±7.5 µm. FEA-predicted LSD were G1 65.2 µm and G2 34.6 µm. The experimental volumetric surface displacement (VSD) was G1 1.22±0.2 mm3 and G2 0.63±0.2 mm3. Theoretically-predicted VSD for G1 1.36±0.2 mm3 and G2 0.67±0.2 mm3. No significant difference (p>0.05) was found in LSD and VSD among the experimental, theoretical and FEA in the same group. Significant differences (p<0.05) were noted between the two groups, with LSD and VSD of G2 values being almost half of G1. This pattern gave an insight of a debond restoration characteristics.

Peri-implant conditions and levels of advanced glycation end products among patients with different glycemic control.

BACKGROUND: A close relationship between poor glycemic control and peri-implant break down has been demonstrated. It is hypothesized that levels of advanced glycation end products (AGEs) in peri-implant sulcular fluid (PISF) are higher with increased glycemic levels in type 2 diabetes mellitus patients. PURPOSE: In the present study, we examined the clinical and radiographic peri-implant parameters and levels of AGEs among different glycemic levels in diabetic patients and assessed whether the levels of AGEs correlate with clinical peri-implant parameters. MATERIALS AND METHODS: Ninety-three patients who participated in this study were divided into four groups; Group-1: HbA1c 6.1%-8%; Group-2: HbA1c 8.1%-10%; Group-3: HbA1c > 10%; Group-4: non-diabetic individuals with HbA1c < 6%. Peri-implant plaque index (PI), bleeding on probing (BOP), probing depth (PD) and crestal bone loss (CBL) were recorded. Levels of AGEs in PISF were quantified using enzyme-linked immunosorbent assay. Between-group comparison of means was verified with Kruskal-Wallis test and Pearson correlation coefficient for correlations of AGE levels with peri-implant parameters. RESULTS: Peri-implant PI, BOP, PD, and CBL were significantly higher in group-1, -2, and -3 as compared to non-diabetic patients (P < .05). These parameters were significantly higher in group-2 and group-3 versus group-1 (P < .01). Mean PI, BOP, PD, and CBL were comparable between group-2 and group-3 patients (P > .05). Mean levels of AGEs in PISF were significantly higher in relation to higher levels of HbA1c levels. Significant positive correlations were found between AGEs and PD (P = .0221) and CBL (P = .0425); and significant negative correlation was found for PI (P = .0376) in patients with HbA1c levels >10%, respectively. CONCLUSIONS: Clinical and radiographic peri-implant parameters were poor and levels of AGEs were significantly high in patients with high glycemic levels. These findings suggest that AGEs may be considered as potential marker of inflammation in diabetic individuals with peri-implantitis.

Efficacy of surgical laser therapy in the management of oral pigmented lesions: A systematic review.

BACKGROUND: Oral pigmentation, especially in the gingiva poses esthetic problems. Laser therapy has been widely used for cosmetic therapy in dentistry. The aim of the present study was to systematically review the efficacy of surgical laser therapy (SLT) in the management of oral pigmented lesions (OPL). MATERIALS AND METHODS: The addressed focused question was "Is SLT effective in the management of OPL?" Databases (MEDLINE via PubMed; EMBASE; Cochrane Central Register of Controlled Trials and Cochrane Oral Health Group Trials Register databases) were searched from 1970 up to and including February 2017. RESULTS: Ten studies were included. The reported number of OPL ranged between 8 and 140. Oral pigmented sites included, gingiva, buccal and labial mucosa, alveolar mucosa and lips. Lasers used in the studies included Q-switched alexandrite, Neodymium-doped yttrium aluminium garnet, diode, Erbium: yttrium aluminium garnet and carbon dioxide laser. Laser wavelength, power output and number of irradiations were 635-10,600nm, 1-10W and 1 to 9 times, respectively. The follow up period ranged from 6 to 24months. All studies reported SLT to be effective in the treatment of OPL. In five studies, recurrence of OPL occurred which ranged from 21.4% to 45%. CONCLUSIONS: Lasers are effective in the management of OPL including physiologic gingival pigmentation, smokers' melanosis and pigmentation in Laugier-Hunziker syndrome. Different laser types (CO2, Er:YAG and Diode) showed comparable outcomes in the treatment of OPL.

TRENDS IN COMPLETE DENTURE IMPRESSIONS IN PAKISTAN.

BACKGROUND: Multiple materials and techniques have been reported for complete denture impressions in literature. The aim of the study was to assess the trends in complete denture impression materials and techniques among general dental practitioners (GDP) and specialists (SP) in Pakistan. METHODS: In this cross-sectional study, self-designed-structured questionnaires were distributed among 500 dentists in Pakistan. The three-part questionnaire enquired about the demographic features, preferred impression materials, impression techniques and related procedures commonly used in their clinical practice. A comparison between the responses of SP and GDP was also drawn. Frequency distribution and Chi-square test were performed to compare the responses. RESULTS: A total of 294 questionnaires were completed at a response rate of 58.8%. 75% of GDP used alginate for primary impressions and 66% of SP preferred impression compound for the same. A majority of both SP and GDP favoured the used of custom trays (SP 81%, GDP 85%) and selective pressure technique (SP 84%, GDP 53%) for final impression. However, 85% of GDP used zinc-oxide eugenol and 62% of SP favoured elastomeric materials for the same. Most of the SP and GDP used chemical cured resin custom trays (SP 54%, GDP 75%), however, 86% of SP used spaced trays and almost 60% of GDP preferred close-fitting trays. CONCLUSIONS: The practice of GDP and SP with regards to CD impression materials and techniques differed significantly. Continued education and training for GDP and SP with respect to procedures and techniques related to CD is recommended.