Effect of Photodynamic Therapy, Er,Cr:YSGG, and Nd:YAG Laser on the Push-Out Bond Strength of Fiber Post to Root Dentin

Objective: To evaluate the push-out bond strength and modes of failure of fiber post to root dentin by using photodynamic therapy (PDT), Er,Cr:YSGG, Nd:YAG laser, and conventional cleaning and shaping (CCS). Materials and methods: Eighty anterior teeth were sectioned in a horizontal manner being 2 mm incisal to the cementoenamel junction, and root canal was prepared for post space. After post space was made, fiber posts were placed inside the root canal system. The fiber posts were subjected to PDT, Er,Cr:YSGG laser, Nd:YAG laser, and conventional cleaning and shaping (CSS) with 20 specimens in each group. Cervical and apical sections were obtained from the specimens. For performing the push-out test, the universal testing machine was used. The formula used for calculating the push-out bond strength was σ = N/mm². Results: PDT group (8.16 ± 2.19 MPa) achieved the highest mean push-out bond strength, whereas Er,Cr:YSGG (7.24 ± 1.27 MPa) reported the lowest value in the specimens. Among the experimental groups, the ANOVA test expressed statistical difference (p = 0.481). In the cervical segments, the mean push-out bond strength was found to be higher in all of the experimental groups. For the cervical segments, the independent t-test results showed higher mean push-out bond strength values than the apical segments in PDT, Er,Cr:YSGG, Nd:YAG, and CSS groups, respectively (p < 0.05). Twenty failures were observed at the interface level between the adhesive and surface of dentin. Seven failures were found at the interface between mixed and the adhesive and post, respectively. Conclusions: Push-out bond strength to root canal dentin was not affected by PDT, Er,Cr:YSGG, and Nd:YAG laser compared with CCS. However, PDT produced the smallest number of failure modes and slightly higher push-out bond strength to root dentin. Laser treatment using PDT and Er,Cr:YSGG appeared to be clinically efficient showing acceptable push-out bond strength of fiber post with less number of failures at different regions of the root dentin.

Efficacy of photodynamic therapy versus local nystatin in the treatment of denture stomatitis: A randomized clinical study

AIM

The aim of the present randomized clinical study was to compare the efficacies of photodynamic inactivation (PDI) to nystatin (NST) in terms of prevalence of Candida species in cases with denture stomatitis (DS).

METHODS

Thirty-six patients were randomly divided into two groups; 18 in PDI and 18 in NST. Irradiation was carried out by using the GaA1As diode laser with wavelength, mode of transmission, laser output and energy density were standardized at 660 nm, continuous mode, 100 mW power and 28 J/cm2 respectively. The PDI was applied twice a week, with an interval of at least 48 h among the sessions during four weeks. Topical nystatin oral suspension 100,000 IU was used four times daily for 15 days. The existence of Candida spp. was confirmed by employing the microbiological culture technique. Candida colony counts from the palates and dentures surfaces, quantified as colony forming unit (CFU)/mL, measured at baseline, at the end of treatments (day 15), and at follow-up (days 30 and 60) and the prevalence of Candida spp. were identified in the two groups of treatments.

RESULTS

The overall CFU/mL values were higher in the dentures of the patients of both the groups than those from the palates. During all time periods of the study, the CFU/mL values obtained from both NST and PDI groups showed no significant differences. For dentures and palates, a significant reduction in mean CFU/mL values was observed on day 15 compared with baseline (day 0) in both NST and PDI groups. It can be seen that the effect size of treatments was large for the palates of patients in the NST group (1.79) and moderate for the palates of patients in the PDI group (0.63). On the other hand, the effect size was very large for the dentures for both groups (NST group = 3.01; PDI group = 1.58). C. albicans was the most common species on both dentures and palates of patients throughout the study period followed by C. tropicalis and C. glabrata.

CONCLUSION

Out of all the Candida spp., C. albicans showed the highest prevalence among all species. In addition, PDI was equally effective as nystatin for the treatment of DS.

Presence of Candida species in the subgingival oral biofilm of patients with peri-implantitis

BACKGROUND

There are no studies that have investigated the presence of Candida species in the subgingival oral biofilm (OB) of patients with peri-implantitis.

PURPOSE

The aim was to assess the presence of Candida species in the subgingival OB of patients with peri-implantitis.

MATERIALS AND METHODS

Individuals with (group A) and without (group B) peri-implantitis were included. Life style related and demographic data were collected using a questionnaire. In both groups, peri-implant plaque-index (PI), bleeding-on-probing (BOP), and probing-depth (PD) were evaluated and crestal bone loss (CBL) were measured on digital bitewing radiographs. In both groups, subgingival OB samples were collected using sterile paper points. Identification of Candida species was performed using ChromAgar medium and colony forming units per milliliter (CFU/mL) were determined. Statistical analysis was performed, and level of significance was set at P < 0.05.

RESULTS

The mean age of individuals in groups A (n = 43) and B (n = 41) were 52.2 ± 4.4 and 55.1 ± 2.3 years, respectively. All participants were male. In groups A and B, implants were in function for 7.4 ± 1.3 and 6.8 ± 0.6 years, respectively. Scores of peri-implant PI (P < 0.001), BOP (P < 0.001), PD (P < 0.001), and CBL (P < 0.001) were significantly higher in group A than group B. Subgingival Candida was isolated from the OB of 33 (76.7%) patients in group A and 5 (12.2%) individuals in group B. The most common yeast species was Candida albicans, which was isolated from 67.4% to 60% individuals in groups A and B, respectively. The number of subgingival oral yeasts CFU/mL were significantly higher in group A (3147.54 ± 1052.6 CFU/mL) compared with group B (496.68 ± 100.2 CFU/mL; P < 0.01).

CONCLUSION

Candida species (predominantly C. albicans) are present in the subgingival OB of patients with peri-implantitis. Community-based efforts toward routine oral hygiene maintenance are needed to improve oral health and minimize the risks of peri-implant diseases in populations.

Effect of scaling and root planing on the expression of anti-inflammatory cytokines (IL-4, IL-9, IL-10, and IL-13) in the gingival crevicular fluid of electronic cigarette users and non-smokers with moderate chronic periodontitis

Purpose

The aim of this cross-sectional study was to investigate the effect of scaling and root planing (SRP) on the expression of anti-inflammatory cytokines (interleukin [IL]-4, IL-9, IL-10, and IL-13) in the gingival crevicular fluid (GCF) of electronic cigarette users and non-smokers with moderate chronic periodontitis (CP).

Methods

Electronic cigarette users and non-smokers with CP were included in the study. Full-mouth plaque and gingival indices, probing depth (PD), clinical attachment loss (CAL), and marginal bone loss (MBL) were assessed. The GCF was collected, and its volume and levels of IL-4, IL-9, IL-10, and IL-13 were assessed. These parameters were evaluated at baseline and 3 months after SRP. The sample size was estimated, and comparisons between groups were performed. P<0.05 was considered to indicate statistical significance.

Results

Thirty-six electronic cigarette users (47.7±5.8 years old) and 35 non-smokers (46.5±3.4 years old) with CP were included. At baseline, there were no differences in plaque index (PI), PD, CAL, MBL, and GCF IL-4, IL-9, IL-10, and IL-13 between electronic cigarette users and non-smokers. At the 3-month follow-up, there were no significant differences in PI, gingival index (GI), PD, CAL, and MBL in electronic cigarette users compared to baseline, while there were significant reductions in PI, GI, and PD among non-smokers. At the 3-month follow-up, GCF IL-4, IL-9, IL-10, and IL-13 levels were significantly elevated in both groups (P<0.05) compared to baseline. The increases in GCF IL-4, IL-9, IL-10, and IL-13 levels were significantly higher in non-smokers (P<0.05) than in electronic cigarette users at the 3-month follow-up.

Conclusions

Levels of GCF IL-4, IL-9, IL-10, and IL-13 increased after SRP in electronic cigarette users and non-smokers with CP; however, the anti-inflammatory effect of SRP was more profound in non-smokers than in electronic cigarette users.

Clinical and radiographic assessment of narrow-diameter and regular-diameter implants in the anterior and posterior jaw: 2 to 6 years of follow-up

Purpose

The present retrospective clinical study aimed to evaluate and compare the clinical and radiographic parameters, complications, and satisfaction in patients who received fixed prostheses supported by narrow-diameter implants (NDIs) in the anterior and posterior jaw.

Methods

Patients aged ≥30 years who had NDI-supported fixed prostheses in the anterior or posterior region of either jaw for at least 2 years were included. Complications such as chipping of the crown; loosening or fracture of the screw, crown abutment, or implant; and loss of retention were recorded. Clinical peri-implant outcomes and crestal bone loss (CBL) were measured. A questionnaire was used to record responses regarding the aesthetics and function of the fixed restorations. Analysis of variance was used to assess the significance of between-group mean comparisons. The log-rank test was performed to analyze the influence of location and prosthesis type on technical complications.

Results

Seventy-one patients (mean age: 39.6 years) provided informed consent with a mean follow-up duration of 53 months. Only bleeding on probing showed a statistically significant difference between NDIs in the anterior and posterior regions. The complication rate for NDIs in the posterior region was significantly higher than that for NDIs in the anterior region (P=0.041). For NDIs, CBL was significantly higher around splinted crowns than single crowns (P=0.022). Overall mean patient satisfaction was 10.34±3.65 on a visual analogue scale.

Conclusions

NDIs in the anterior and posterior jaws functioned equally well in terms of peri-implant soft and hard tissue health and offered acceptable patient satisfaction and reasonable complication rates.

Clinical and radiographic indices around narrow diameter implants placed in different glycemic-level patients

BACKGROUND

Studies assessing peri-implant clinical and marginal bone resorption (MBR) around narrow diameter implants (NDIs) placed in different glycemic levels are uninvestigated.

OBJECTIVE

The present 3-year retrospective follow-up investigation was designed to explore clinical and radiographic status of NDIs placed in individuals with different glycemic control levels.

MATERIALS AND METHODS

Patients with serum hemoglobin A1c (HbA1c) levels ≥6.5% (Group-1), 5.7%-6.4% (Group-2), and 4.0%-5.0% (Group-3) were included. Clinical indices evaluating bleeding on probing (BOP), plaque scores (PI), peri-implant probing depth (PD), and MBR were recorded around NDIs at 1-, 2-, and 3-year follow-up. Serum HbA1c test was carried out for all patients to assess the profile of glycosylated hemoglobin at 1 and 3 years of follow-up.

RESULTS

A significant reduction in mean HbA1c levels from year 1 to year 3 follow-up period was seen in Group-1 only. PI varied from 0.40 in Group 1 at 2 year and 0.42 at 3-year follow-up to 0.18 at 2-year (P = 0.032) and 0.17 at 3-year (P = 0.018) follow-up, respectively. Greater BOP was noted in Group 1 (0.53) as compared with Group 2 (0.42) and Group 3 (0.21) (P = 0.048) at 3-year follow-up. PD after 3 year ranged from 2.04 mm in Group 3 to 2.32 mm in Group 1 that showed statistically significant difference (P = 0.037). No statistical significant differences were observed in MBR at any time point between the groups.

CONCLUSION

The results of this short-term follow-up study indicate that NDIs show clinical and radiographic stability, provided oral cleanliness and glycemic levels are relatively maintained. Further long-term clinical studies are needed to evaluate implant stability over the period along with controlled glycemic status.

Clinical, radiographic, and restorative peri-implant measurements of narrow and standard diameter implants in obese and nonobese patients: A 3-year retrospective follow-up study

BACKGROUND

There is dearth of studies assessing clinical, restorative, and radiographic peri-implant outcomes around narrow diameter implants (NDIs) and standard diameter implants (SDIs) in obese and nonobese subjects.

OBJECTIVE

To assess clinical, restorative, and radiographic parameters of NDIs and SDIs placed in obese and nonobese individuals.

MATERIALS AND METHODS

Obese and nonobese patients requiring NDIs and SDIs in the anterior maxilla/mandible were included. Based on the implant diameter, participants were further divided into two subgroups: (a) NDIs (3.3 mm) and (b) SDIs (4.1 mm). Peri-implant clinical measurements including plaque index (PI), bleeding on probing (BOP), probing depth (PD), and radiographic crestal bone loss (CBL) were evaluated around NDIs and SDIs at 1 and 3-year follow-up.

RESULTS

A total of 70 patients (35 obese and 35 nonobese) were included. Only BOP showed statistically significant differences between both the groups at patient level at 1 and 3-year follow-up (P < .05). There was no statistically significant difference in PI and PD around NDIs and SDIs between obese and nonobase patients. Statistical significant differences were observed in the total CBL around NDIs and RDIs among obese and nonbase subjects at 3 year follow-up (P < .05).

CONCLUSION

Both NDIs and SDIs show consistent clinical stability among obese and nonobase patients. Higher amount of bone loss was observed in obese patients compared to nonobase patients despite regular hygiene maintenance.

Survival of Titanium-Zirconium and Titanium Dental Implants in Cigarette-smokers and Never-smokers: A 5-Year Follow-up

OBJECTIVE

To compare the peri-implant clinical and radiographic status around bone-level narrow-diameter titanium-zirconium (TiZr) implants and titanium (Ti) implants placed in cigarette-smokers (CS) and never-smokers (NS).

METHODS

Partially edentulous CS and NS rehabilitated with TiZr and Ti implants were included. Demographic data and information regarding smoking habits were collected. Participants were divided into four groups: group-1, CS with TiZr implants; group-2, NS with TiZr implants; group-3, CS with Ti implants; and group-4, NS with Ti implants. 36, 30, 31 and 33 implants were placed in 24, 23, 24 and 25 male individuals in groups 1, 2, 3 and 4, respectively. Peri-implant plaque index (PI), bleeding on probing (BOP), probing depth (PD) and mesial and distal crestal bone loss (CBL) were measured. All patients were enrolled in biannual routine oral prophylaxis care at least until the fifth year of follow-up and oral hygiene instructions were reinforced at each recall appointment. P < 0.05 was considered statistically significant.

RESULTS

At the 3- and 5-year follow-ups, there was no statistically significant difference in the peri-implant PI, BOP, PD and CBL between individuals in all groups. In all groups, the implant success and survival rates were 100% and 100%, respectively, at the 5-year follow-up.

CONCLUSION

The TiZr and Ti dental implants can remain clinically and radiographically stable in CS in a manner similar to NS. Routine oral hygiene maintenance plays an essential role in this regard.

Effect of contemporary retraction agents and cleaning with hydrogen peroxide on the polymerization of elastomeric impression materials

The aim of the study is to investigate the polymerization inhibition of elastomeric impression materials vinylpoly siloxane (VPS) and polyether (PE) when used in combination with retraction materials with and without subsequent cleaning with hydrogen peroxide (H₂O₂). Methods: Seven stainless steel specimens were fabricated. Four hundred and twenty impressions were made with three different elastomeric materials (140 each) as follows: group 1: VPS-Panasil; group 2: VPS-Express; group 3: PE-Monophase. Each material group was further subdivided into seven subgroups, based on use of no retraction material (control), three different retraction materials [Retraction capsule (RC3M), Dryz, Expasyl], and two cleaning techniques (water and H₂O₂). All subgroups included 20 impressions, which were made by a single operator using an automix gun. Evaluations were made using a visual scale by three calibrated examiners blindly and independently. Subjective categorization of the impressions were made as inhibited and uninhibited. Data were analyzed using Fisher's exact test and significance was set at p < 0.05. Results: Inhibited impressions were lower than uninhibited impressions among VPS materials (Panasil and Express); Panasil and Express showed comparable (p > 0.05) impression retardation. PE showed significantly higher inhibition compared to VPS materials (p < 0.05). Expasyl showed significantly higher polymerization inhibition than other retraction materials (p < 0.05). The use of H₂O₂ for cleaning showed significant reduction in polymerization inhibition than cleaning with water for Expasyl (p < 0.05). Conclusion: Overall contemporary retraction materials showed low potential for polymerization inhibition of elastomeric impression materials. Expasyl should be cleaned with H₂O₂ prior to impression making. However, Dryz and RC3M can show accurate impressions with water cleaning alone.

Clinical Evaluation of Short Tuberosity Implants among Type 2 Diabetic and Non-Diabetic Patients: A 5 Year Follow-Up

Aim: To assess clinical and radiographic parameters including bleeding on probing (BoP); probing depth (PD), plaque index (PI) and crestal bone loss (CBL) around short tuberosity implants (STI) supporting fixed partial dentures in patients with Type 2 diabetes mellitus (T2DM) and non-diabetics. Material and Methods: Participants with T2DM and without T2DM with at least one STI (6 mm) posteriorly restored with a fixed partial denture splinting premolar implant were included. A questionnaire collected demographic details including gender, age, duration of diabetes, habits of brushing, the total number of dental implants and location, implant loading after placement, restoration type, and family history of DM. Clinical and radiographic assessment of peri-implant parameters, i.e., bleeding on probing (BoP), probing depth (PD), plaque index (PI), and crestal bone loss (CBL) was performed. The restorative success of STI was determined by no sensation of the foreign body, lack of pain and dysesthesia, lack of infection, no radiolucency around the implant, and no mobility. The Kruskal-Wallis test was used for statistical analysis. A p-value of less than 0.05 was considered statistically significant. Results: Twenty-five T2DM (19 males and 6 females) and 25 non-diabetic (18 males and 7 females) participants were included. The number of STIs in T2DM was 41, whereas in non-diabetic it was 38. At 1 year follow-up, mean PI% in T2DM participants was 18.9% (19.2-21.4%) and in non-diabetics it was 17.6% (16.3-18.5%). The mean PD was recorded in diabetics (1.3 ± 5.0 mm) and non-diabetics (1.1 ± 3.2 mm). The BoP value in diabetics was 44.9% (39.8-46.4%) and 28.2% in non-diabetics (17.2-24.6%). At 5 years of follow-up, the mean PI% range in T2DM participants was 26.18% (25.4-29.1%) and 24.42% in non-diabetic (20.1-25.5%). The mean PD in millimeters around STI in T2DM was observed to be 2.3 ± 4.8 mm and 1.4 ± 3.4 mm in non-diabetics. In addition, BoP in diabetic participants was 39.54% (27.7-42.1%) and 24.42% in non-diabetics (20.1-25.5%). A total of six STIs failed, i.e., two in the non-diabetic and four in the T2DM group. Conclusions: Patients with T2DM have poor periodontal (BoP, PD, CBL) and restorative peri-implant parameters around STIs when compared to healthy (non-diabetic) participants at five years of follow-up. For long-term stability, glycemic control is pivotal along with following good plaque control.

Influence of contemporary ceramo-metallic crown decontamination on the surface roughness, color stability, and disinfection. An in vitro analysis

AIM

To assess the antimicrobial effects, surface roughness (Ra), and color change (ΔE) of Morinda Citrofolia, Sapindus Mukorossi, Indocyanine green photosensitizer, and 2% NaOCl on metal ceramic crown colonized with C. Albicans, S aureus, S. mutans, and E. coli.

MATERIAL AND METHODS

An aggregate of 40 (n = 10 each) Ni/Cr metal-ceramic crowns were fabricated and inoculated with the American Type Culture Collection (ATCC) of varied microbial colonies colonized by C. Albicans, S aureus, S. mutans, and E. coli. After inoculation, specimens were exposed to four different types of disinfection methods i.e. group 1: MC, group 2: SM, group 3:ICGP, and group 4 2% NaOCl respectively to evaluate antimicrobial efficacy, Ra, and color change. Later, the microbial assay was performed and expressed as CFU/ml (log 10). Ra was assessed using a surface analyzer and color change ΔE was evaluated using a spectrophotometer Statistical analysis was performed by using two-way ANOVA and Post HocTukey's test maintaining a significance level of p less than 0.05.

RESULTS

The highest antimicrobial efficacy for metallic-ceramic crown decontamination against all inspected microbial colonies was unveiled by group 1: MC, whereas the lowest disinfection efficacy was revealed by group 4 sterilized with 2% NaOCl (control). Metallic ceramic crown decontamination with MC and SM substantiated equivalent antimicrobial efficacy in plummeting CFU/mL (log10) of C.Albicans, S aureus, S.mutans, and E. coli (p>0.05). However, ICGP as a crown disinfectant validated antimicrobial efficacy significantly less compared to MC and SM (p<0.05). Ra was assessed post-disinfection with no changes observed (p>0.05) among all groups. Similarly, ΔE was significantly higher in crowns disinfected with ICGP (p<0.05) CONCLUSION: Metallic ceramic crown decontamination using herbal disinfectants Morinda Citrofolia and Sapindus Mukorossi exhibited favorable antimicrobial efficacies against microbial colonies of C. albicans, S aureus, S.mutans, and E. coli with no changes in surface roughness and color.

Efficacy of canal disinfectants Temoporfin, carbon nanoparticles, and Er: YAG laser on martens hardness, smear layer removal, and bond strength of glass fiber posts to canal dentin

AIM

To investigate the effectiveness of unconventional post space disinfection techniques, specifically Er:YAG laser, Temoporfin, and Carbon Nanoparticles (CNPs), in improving Martens hardness (MH), eliminating the smear layer (SL), and enhancing the push-out bond strength (PBS) of glass fiber posts in canal dentin.

METHODS

An in vitro study was conducted utilizing 80 single-rooted extracted human teeth, which were decoronated and subjected to standardized root canal preparation. The teeth were equally distributed into four experimental groups: Group 1 (NaOCl + EDTA), Group 2 (Er: YAG laser + EDTA), Group 3 (Temoporfin + EDTA), and Group 4 (CNPs + EDTA). Each group underwent disinfection protocols followed by assessment of Martens hardness (MH) using nanoindentation testing, SL evaluation via scanning electron microscopy, and bond strength testing using a universal testing machine (UTM). Statistical analysis was performed using one-way ANOVA followed by Tukey's post hoc test to determine the level of significance among the groups. A significant level of p<0.05 was established.

RESULTS

Group 4 (CNPs+17 % EDTA) showed a high MH value of (0.25 ± 0.02 GPa), significantly outperforming Groups 1 (0.13 ± 0.02 GPa) and 3 (0.10 ± 0.03 GPa). Group 2 (Er: YAG laser + 17 % EDTA) demonstrated superior smear layer removal across all sections, particularly in the apical third (1.94 ± 0.38). Push-out bond strength was highest in Group 2 (9.98 ± 0.14 MPa at the cervical level) and Group 4 (10.08 ± 0.21 MPa), while Group 1 showed a decrease in apical bond strength of (5.11 ± 0.19 MPa) CONCLUSION: CNPs and Er:YAG laser treatments, in comparison to Temoporfin and NaOCl, significantly increase dentin hardness and bond strength while reducing SL. This finding suggests that the incorporation of these innovative disinfection methods into endodontic procedures may enhance the durability and success of glass fiber post restorations.

Evaluation of gingival displacement, bleeding and ease of application for polytetrafluoroethylene (PTFE) and conventional retraction cord - a clinical trial

OBJECTIVE

Conventional use of retraction cord in soft tissue management is effective only when the non-resilient nature of material does not jeopardize gingival health. Therefore this study aims to clinically evaluate the gingival displacement, ease of application and bleeding from polytetrafluoroethylene (PTFE) retraction cord.

PATIENTS AND METHODS

This study is a single-center, parallel-group, randomized controlled clinical trial (1:1). Sixty patients indicated for full coverage metal-ceramic restoration for first molars were enrolled and randomly allocated to experimental (PTFE Cord) and control (conventional plain retraction cord) groups. After crown preparation and isolation, a pre-displacement impression was made. Assigned gingival displacement material was applied for 5 minutes, followed by post-displacement impression. Casts were prepared and used for assessment of mean horizontal gingival displacement by measuring displacement using a stereomicroscope (20 x). Post-displacement gingival bleeding and ease of application were also assessed clinically. t-test and Chi-square tests were used for statistical assessment of gingival displacement, gingival bleeding and ease of application.

RESULTS

Gingival displacement, bleeding and ease of application were similar among study groups (p > 0.05). Mean gingival displacement in the experimental group was 197.1 µm, and 167.7 µm in the control group. Bleeding was observed in 30% and 20% of cases of experimental and control group, respectively. Ease of application was 'difficult' in 53.3% and 43.3% of cases of experimental and control group, respectively. Non-impregnated gingival retraction cord and PTFE cord displayed similar outcomes of gingival displacement, ease of placement and bleeding after cord removal.

CONCLUSIONS

Post-displacement bleeding and discomfort for PTFE cord placement suggest that this technique needs improvement. Therefore further studies are warranted to improve and investigate the physical and biological response to PTFE retraction cord.

Effect of Framework's Manufacturing Technique on Screw's Preload of Implant Supported Prosthesis

Background

Implant supported prosthesis is a common treatment modality. Nowadays, new manufacturing techniques are available to fabricate them.

Aims

To evaluate the effect of different manufacturing techniques of implant supported frameworks (ISF) on the preload of abutment's screws.

Materials and Methods

A mandibular edentulous acrylic model with four dental implants temporarily stabilized in the interforaminal area was used. One ISF was fabricated using the conventional technique; implants were removed from the model and reassembled into the framework; this framework served as the passively fitting framework (PF). Three additional frameworks were constructed: conventional cast framework (CF), milled framework (MF) and 3D-printed framework (3D-PF). The gap between the frameworks and the neck of the implants were recorded in microns using a digital microscope. A tightening torque (TT) of 35 N·cm was applied to all the four abutments' screws and the screw's preload was recorded using two methods, by strain gauges (SGs) that were attached to the neck of each implant and fed into a stain book in microstrain (μɛ) and by removal torque (RT) using a digital torque meter.

Results

The frameworks' gap means from the lowest to the highest were PF, CF, 3D-PF, and MF. The RT was significantly lower than the TT in all frameworks (P ≤ 0.05). One-way analysis of variance (ANOVA) revealed that the PF had the lowest RT, while the CF and the 3DPF both had the highest RT, and those differences were found to be statistically significantly (P ≤ 0.05). When preload of the frameworks was recorded by SGs, one-way ANOVA revealed that PF had the highest preload value, while both 3D-PF and MF had the lowest preload values, those differences were also found to be statistically significant (P ≤ 0.05).

Conclusion

The fabrication of implant-supported frameworks using milling or selective laser melting computer aided design/computer-aided manufacturing technologies did not necessarily enhance the screw's preload. This lack of enhancement could be attributed to the great amount of marginal gap in the frameworks fabricated by both techniques.

Clinical, Radiographic Peri-Implant Parameters and Patient Satisfaction with Splinted and Non-splinted Short Dental Implants in the Maxillary Premolar-Molar Region: A Long-Term Retrospective Clinical Study

PURPOSE

The goal of this study was to assess the peri-implant condition, peri-implant bone loss (PBL), and complication rates of short dental implant-supported splinted crowns (SDI-SCs) and non-splinted crowns (SDI-NSCs) in the maxillary premolar-molar region.

MATERIALS AND METHODS

Patients who had short implants placed near their maxillary sinuses were evaluated. Both patient satisfaction and presence of any technical complication, e.g. porcelain wear and chipping, loss of retention and loosening of the abutment, fixture or screw, were noted. The peri-implant plaque index (PIPI), probing depth (PIPD), bleeding on probing (PIBP), and peri-implant bone loss (PBL) were evaluated. To assess the impact of prosthesis type and SDI placement on technical problems, a log-rank test was computed. p < 0.05 was considered statistically significant.

RESULTS

A total of 72 patients agreed to be followed-up, showing a mean follow-up time of 3.1 years. Ninty-five implants in total (55 SDI-SCs, and 40 SDI-NSCs) with moderately rough surfaces were evaluated. The average PBL score for implant and patients was 1.27 (0.02-3.97) and 1.25 (0.03-4.41), respectively. More technical complications were observed with single crowns than with splinted crowns. There were no statistically significant differences in the peri-implant parameters between SDI-SCs and SDI-NSCs (p > 0.05). PBL at molar sites was substantially higher than at premolar sites (p = 0.048). Sixty patients (83.3%) were satisfied with the appearance of the crowns, while 57 patients (79.1%) were satisfied with the crowns' performance.

CONCLUSION

The peri-implant conditions, bone levels, technical complication rates and patient satisfaction were comparable between the SDI-SCs and SDI-NSCs. However, implants placed in the molar sites had statistically significantly greater bone loss in comparison to those at the premolar sites.

Clinical, Radiographic, and Inflammatory Peri-Implant Parameters around Narrow Diameter Implant Crowns among Prediabetic and Non-Diabetic Subjects

Background and Objectives: To compare the clinical, radiographic, and inflammatory peri-implant parameters around narrow diameter implants (NDI) supported single and splinted crowns in non-diabetics and prediabetes. Materials and Methods: The clinical and radiographic parameters and the levels of IL-6 and TNF-α in the peri-implant crevicular fluid (PICF) of narrow diameter single (NDISCs) and splinted (NDISPs) crown implants were assessed both in non-diabetics and participants with prediabetes. The glycemic state of the patient was assessed using glycated hemoglobin (HbA1c) levels. The peri-implant soft tissue indices (Plaque index (PI), bleeding on probing (BoP), probing depth (PD)) and marginal bone loss were recorded and compared between the groups. Success of the prosthesis was assessed by the frequency of technical complications and patient satisfaction. Inter-group comparison was performed using ANOVA (one-way analysis of variance) while the normal distribution of dependent variables was calculated using Shapiro-Wilk. A p-value of less than 0.05 was considered to be statistically significant. Results: Sixty participants (30 non-diabetics and 30 with prediabetes) with a total of 178 (118 NDISCs and 60 NDISPs) platform-switched NDIs were a part of the study. Of the 118 NDISCs, 56 were placed in the non-diabetic individuals and 62 were placed in the prediabetes group whereas 30 NDISPs each were placed in both the study groups. The clinical parameters of PI, BoP and PD in the single crown and splinted crown groups showed comparable results. However, a statistically significant difference (p-value of less than 0.05) in PI, BoP and PD and in the values of IL-6 and TNF-α was found when a comparison was made between the non-diabetes and prediabetes group. A total of 91% of the patients were satisfied with the esthetics of the implants while 79% of the patients showed satisfaction with function. Conclusions: All the clinical and radiographic parameters were statistically similar in both single and splinted types of narrow diameter implants. However, the bone loss, probing depth, plaque index, and levels of inflammatory markers were statistically higher in prediabetes as compared to non-diabetes implying that a slight hyperglycemic state impacts peri-implant health.

Influence of Expasyl and Viscostat on Bond Strength of Resin Composite to Dentin with Different Adhesives

The aim of the present study was to evaluate the influence of gingival retraction agents and different bonding regimes on the shear bond strength (SBS) of dentin to resin composite. Sixty human teeth were divided into six groups (n = 10) based different combinations of hemostatic agents (Viscostat and Expasyl) and dentin bonding regimes [Total-etch (TE) and self-etch (SE)]. Group A1, Expasyl and TE; group A2: Expasyl and SE; group B1: Viscostat and TE; group B2: Viscostat and SE, group C1 (control): No hemostatic agent and TE; group C2 (control): No hemostatic agent and SE. Composite build-ups (Tetric N Ceram) were performed after dentin treatments and SBS was assessed using universal testing machine. Failure analysis was performed with a stereomicroscope and classified as adhesive, cohesive and admixed. Data was analysed using ANOVA and multiple comparisons test. The maximum and minimum SBS was displayed by specimens in group C1 (36 59 ± 5 94 MPa) and group B2 (17 95 ± 2 52 MPa) respectively. Control groups (C1 and C2) showed statistically comparable SBS, which was significantly higher in comparison to experimental groups (A1, A2, B1, and B2) (p < 0.05). Hemostatic agents inhibited the adhesive bond strength of composite to tooth dentin. Reversal effect of total-etch and self-etch bonding regimes on hemostatic agent treated dentin SBS was minimal.

Implant abutment disinfection using plasma of argon and 0.2% and chlorhexidine gel applications immediately before prosthesis delivery: clinical and radiographic status at 5-years of follow-up

OBJECTIVE

The purpose of this five-year follow-up study was to investigate the clinical and radiologic status of implants that had undergone abutment disinfection immediately prior to prosthetic loading (PL) using plasma of argon (PA) or 0.2% chlorhexidine (CHX) gel.

PATIENTS AND METHODS

Sixty patients who had had an implant-supported prosthesis fitted at least five years previously were recruited for this study. In groups 1, 2, and 3, implant abutment disinfection was performed using PA, 0.2% CHX, and a vapor protocol, respectively. Modified plaque index (mPI), modified bleeding index (mBI), probing depth (PD), and mesial and distal crestal bone loss (CBL) were measured. A questionnaire on routine oral hygiene, smoking habits, and systemic health status was also administered. Sample size estimation was performed, and group comparisons were made. Probability values less than 0.05 were considered statistically significant.

RESULTS

Group 1, 2, and 3 included 20 (20 implants) patients each. At five-year's follow-up, there was no difference in mBI, mPI, and PD in all groups. There was no significant difference in peri-implant CBL in all patients. None of the patients were immunosuppressed or had periodontal disease, and or had used nicotinic products within the past five years. Toothbrushing twice daily was reported by at least 90% of individuals in all groups. Flossing of interproximal spaces once daily was reported by at minimum 60% of individuals in all groups.

CONCLUSIONS

Disinfection of implant abutments directly before PL can be performed using AP, or 0.2% CHX gel.