Dental implant considerations in patients with systemic diseases: An updated comprehensive review.

BACKGROUND: Various medical conditions and the drugs used to treat them have been shown to impede or complicate dental implant surgery. It is crucial to carefully monitor the medical status and potential post-operative complications of patients with systemic diseases, particularly elderly patients, to minimize the risk of health complications that may arise. AIM: The purpose of this study was to review the existing evidence on the viability of dental implants in patients with systemic diseases and to provide practical recommendations to achieve the best possible results in the corresponding patient population. METHODS: The information for our study was compiled using data from PubMed, Scopus, Web of Science and Google Scholar databases and searched separately for each systemic disease included in our work until October 2023. An additional manual search was also performed to increase the search sensitivity. Only English-language publications were included and assessed according to titles, abstracts and full texts. RESULTS: In total, 6784 studies were found. After checking for duplicates and full-text availability, screening for the inclusion criteria and manually searching reference lists, 570 articles remained to be considered in this study. CONCLUSION: In treating patients with systemic conditions, the cost-benefit analysis should consider the patient's quality of life and expected lifespan. The success of dental implants depends heavily on ensuring appropriate maintenance therapy, ideal oral hygiene standards, no smoking and avoiding other risk factors. Indications and contraindications for dental implants in cases of systemic diseases are yet to be more understood; broader and hardcore research needs to be done for a guideline foundation.

Effect of shape and design of the internal connection of tissue-level and bone-level implants on detorque values and removal forces: An in vitro study.

STATEMENT OF PROBLEM: Optimal implant stability and preventing complications such as screw loosening are paramount concerns for implant-supported prostheses. However, studies examining the influence of various internal connection designs on detorque values and removal forces, critical aspects of implant success, are lacking. PURPOSE: The purpose of this in vitro study was to assess the impact of the shape and design of the internal connection in tissue-level and bone-level implants on the detorque value and the force required for abutment removal from the implant. MATERIAL AND METHODS: Forty dental implants were securely mounted in 10×6×20-mm acrylic resin blocks positioned perpendicular to the surface. The implants were divided into 4 groups (n=10): bone-level SM Torx, tissue-level PSI Torx, bone-level UF Hex, and tissue-level UF Hex implants. After exposure to a dynamic loading test at 31.2 N, 2 Hz and 106 cycles, measurements were made of both detorque values and removal forces. Statistical analyses, including 1-way ANOVA with a post hoc Tukey test and Kolmogorov-Smirnov test, were conducted to assess the results (α=.05). RESULTS: The differences in detorque values among the 4 groups were statistically similar (P=.087). In terms of removal force values, tissue-level PSI implants exhibited the highest values, while bone-level UF implants had the lowest values, with significant differences in the removal forces among the 4 groups (P<.001). Pairwise comparisons revealed significant differences among the groups (P<.001), except for the comparison between tissue-level PSI and bone-level SM implants (P=.108). CONCLUSIONS: While detorque values remain consistent across implant types, the shape and design of the internal connection of implants has a significant impact on the removal force required for abutment detachment from the implant.

Effect of ceramic thickness on the polymerization quality and film thickness of dual-polymerizing versus heated light-polymerizing adhesive cement.

STATEMENT OF PROBLEM: The clinical success of ceramic veneers cemented with preheated composite resin has been reported to be acceptable. Although the cementing technique requires sufficient light energy to activate its polymerization, the ability of light to penetrate through ceramic restorations of different thicknesses is unclear. PURPOSE: The purpose of this in vitro study was to evaluate the polymerization quality and bond joint thickness of a dual-component adhesive and a heated composite resin when bonding ceramic onlays of varying thicknesses. MATERIAL AND METHODS: Sixty noncarious maxillary premolars, extracted for orthodontic or periodontal reasons, were divided into 6 groups (n=10) and sectioned apically to the marginal ridge. Computer-aided design and computer-aided manufacturing (CAD-CAM) was used to create onlays of varying thicknesses. Following the manufacturers ' instructions, the onlays were cemented using a dual-polymerizing resin for group DP1, DP2, and DP3 groups and preheated light-polymerizing resin for groups LP1, LP2, and LP3. The numbers indicate onlay thickness in each group. Vickers testing was performed 24 hours after polymerization, with a 0.49-N static load applied for 10 seconds. Film thickness was analyzed under an optical microscope, and temperature changes were measured using a thermal imaging camera. Statistical analysis was done with the 2-factor mixed ANOVA tests (α=.05). RESULTS: The Vickers hardness of a dual-polymerizing cement was lower compared with heated light-polymerizing cement (P<.05). Moreover, the thickness of the resin-ceramic restoration did not significantly affect the polymerization of a dual-polymerizing cement. However, the polymerization of the preheated light-polymerizing composite resin in group LP3 was significantly lower compared with other thicknesses (P<.05). In group LP3, the Vickers hardness of the tooth adjacent to the surface of the cement (DX2) was lower compared with indentations closer to the restoration surface (DX3, DX6), demonstrating a reduction in polymerization in the internal part. In addition, the mean film thickness of the dual-polymerizing groups (96 ±18 µm) was significantly lower than of the heated light-polymerizing groups (294 ±64 µm) (P<.05). A temperature reduction of 15 °C in the heated composite resin was also observed after 8 seconds CONCLUSIONS: The thickness of the ceramic restoration did not significantly affect the polymerization of a dual-polymerizing cement. However, the polymerization of the preheated light-polymerizing composite resin under the same ceramic restoration with a thickness of 3 mm was significantly lower. In addition, the mean film thickness for the dual-polymerizing composite resin groups was significantly lower than for the heated light-polymerizing composite resin groups.

Comparison of full-arch mandibular reconstruction with dental implants using completely splinted or segmentally splinted prostheses with two different occlusal schemes: A finite-element analysis.

PURPOSE: This study aimed to comparatively analyze full-arch mandibular reconstruction using dental implants. It focused on two distinct prosthesis configurations: completely splinted and segmentally splinted. These configurations were evaluated under two different occlusal schemes-group function and canine guidance-utilizing finite element analysis (FEA). MATERIALS AND METHODS: The methodology involved developing three-dimensional finite element models from computed tomography data acquired from an edentulous patient. Six dental implants were utilized to complete the mandibular reconstruction. Prosthetic reconstruction was conducted with completely and segmentally splinted prostheses, each employing group function and canine guidance occlusal schemes. Consequently, four distinct models were analyzed. Following meshing, a 200 N load was applied at a 30-degree angle. Subsequent evaluation encompassed stress, strain distribution, and the overall deformation of the implants, crowns, and underlying bone structure assessment. RESULTS: The group function occlusal scheme generally exhibited lower stress values than the canine guidance occlusal scheme, with three-piece prostheses demonstrating even lower stress levels than one-piece prostheses. Conversely, the canine guidance occlusal scheme exhibited higher stress values overall. CONCLUSION: The findings of this study may assist clinicians in selecting the most effective occlusal scheme and prosthetic configuration for implant-supported mandibular restorations, potentially enhancing treatment outcomes and reducing the risk of mechanical complications. In summary, results indicated that group function loading, irrespective of prosthesis type, offers more uniform load distribution and lower stress values, making it a preferable choice over canine guidance. Within the group function occlusal scheme, three-piece prostheses demonstrated lower stress values than one-piece prostheses, but the clinical significance of this difference appears to be minimal.

Enhancing oral function: A case report on mandibular overdenture utilization with custom-made subperiosteal implant.

Subperiosteal implants, previously set aside because of complications, are now emerging again as effective treatments for severe mandibular atrophy, aided by recent improvements in digital dentistry. Traditional dentures in such cases often face challenges with support and retention, necessitating complex regenerative procedures. This paper presents a case report of a 54-year-old male patient with significant mandibular atrophy who received a custom-made subperiosteal implant, showcasing promising results. The implant was precisely designed utilizing computed tomography (CT) scans, a 3D-printed model, the selective laser melting (SLM) technique, and constructed with biocompatible Ti6Al4V material. This innovative approach offered a practical solution, resulting in high patient satisfaction and no complications over a year of use.

Prevalence and antimicrobial resistance of bacterial agents isolated from the cases of dental caries.

Dental caries are mainly occur owing to the presence and activity of bacterial agents. The present study was done to assess the prevalence and antibiotic resistance of bacterial strains isolated from the cases of dental caries. Fifty patients with approved dental carries were included in the study. Sampling from the site of dental caries was done using the sterile swab. Swabs were transferred to laboratory and subjected to microbial culture. Species identification of bacteria was done using biochemical test. Bacterial isolates were subjected to disk diffusion to assess their antimicrobial resistance. S. aureus (40%) harboured the highest rate of contamination, while S. oralis (16%) and E. aerogenes (10%) harbored the lowest. S. aureus and S. mutans (6%) harbored the highest distribution amongst the cases of mix infections, while S. aureus and S. oralis (2%) harbnored the lowest. S. aureus strains harbored the highest rate of resistance toward tetracycline (90%), penicillin (75%), ampicillin (75%), amoxicillin (60%), and erythromycin (60%). E. coli strains harbored the highest rate of resistance toward tetracycline (90%), gentamicin (80%), ampicillin (70%), and erythromycin (70%). S. mutans strains harbored the highest rate of resistance toward tetracycline (93.33%), ampicillin (86.66%), penicillin (80%), amoxicillin (80%), and erythromycin (80%). S. oralis strains harbored the highest rate of resistance toward tetracycline (100%), ampicillin (75%), penicillin (62.50%), and amoxicillin (62.50%). E. aerogenes strains harbored the highest rate of resistance toward tetracycline (80%), gentamicin (80%), and ampicillin (80%). S. aureus bacteria isolated from dental caries harbored the highest rate of MDR. Distribution of resistance against more than 3 antimicrobial agents amongst the S. aureus, E. coli, S. mutans, S. oralis, and E. aerogenes bacteria isolated from the cases of dental caries was 90%, 60%, 80%, 62.50%, and 80%, respectively. Application of disk diffuin can help practitioners to reduce the rate of resistance in bacteria responsible for dental caries.

Prosthetic reconstruction of a patient with an irradiated rhinectomy and upper lip resection with a maxillofacial prosthesis and removable complete dentures: A clinical report.

When surgery is performed to remove aggressive cancer, the extent of the lesion commands the amount of tissue removed. The removal of extensive tissue such as crucial landmarks complicates prosthesis design. This clinical report describes the prosthetic reconstruction of a patient who underwent tumor resection of the upper lip, anterior portion of the nasal cavity, and cartilaginous portion of the nasal septum, as well as subsequent radiation therapy. The prosthetic rehabilitation consisted of magnetic attachments, eyeglasses, and silicone adhesives. The applied technique effectively covered the site of squamous cell carcinoma removal providing natural color and form.

Does the crown-implant ratio affect the survival and complications of implant-supported prostheses? A systematic review.

STATEMENT OF PROBLEM: The use of dental implants shorter than 10 mm in length increases the crown-implant ratio. Whether an increased crown-implant ratio affects the survival rate and complications is unclear. PURPOSE: The purpose of this systematic review was to investigate the effect of the crown-implant ratio on the survival rate and complications of implant-supported prostheses. MATERIALS AND METHODS: Five databases (PubMed, MEDLINE, Scopus, Google Scholar, and Cochrane) were electronically and manually searched for longitudinal studies with a follow-up period of 3 years or longer. The study question was "Does the crown-implant ratio affect survival rate and complications of implant-supported prostheses?" The outcomes investigated were implant survival rate, peri-implant bone resorption rate, implant fracture rate, and other technical complications in the implant components. RESULTS: A total of 670 studies were identified from the research in the databases. By applying the inclusion and exclusion criteria to the full texts, 17 articles were included for descriptive analysis. Qualitative data analysis showed that the survival rate of implant-supported prostheses with a crown-implant ratio greater than 2 was 97.2%, and for a ratio lower than 1, it was about 97.6%. Moreover, 9 papers reported that increasing the crown-implant ratio reduced bone resorption, while 8 other studies reported no significant association between the increase in the crown-implant ratio and bone resorption. CONCLUSIONS: No significant relationship was found between the crown-implant ratio and implant survival rate. However, increasing the crown-implant ratio is likely to decrease bone loss around the implant. Information was insufficient to analyze the relationship between the crown-implant ratio and technical complications in implant-supported prostheses.

Effect of multiple firings on the shear bond strength of presintered cobalt-chromium alloy and veneering ceramic.

STATEMENT OF PROBLEM: How multiple firing cycles may affect the oxide layer and, consequently, the shear bond strength of metal-ceramic restorations is unclear. PURPOSE: The purpose of this in vitro study was to determine the effect of multiple firings on the shear bond strength of porcelain to cobalt-chromium (Co-Cr) alloy. MATERIAL AND METHODS: Forty cylinders (Ø6.8×9 mm) of a representative presintered Co-Cr alloy (Ceramill Sintron) were prepared with computer-aided design and computer-aided manufacturing (CAD-CAM) technology. After airborne-particle abrasion and polishing, the specimens were ultrasonically cleaned of surface contaminants. A circular surface (Ø4×2 mm) was veneered on each specimen with porcelain (VM13) after 3 firings (wash opaque, opaque, and dentin). The specimens were then randomly divided into 4 groups (n=10). The normal group underwent 3 firings. The other groups underwent an additional porcelain firing: the one-plus firing group underwent 4 firings, the two-plus firing group underwent 5 firings, and the three-plus firing group underwent 6 firings. Next, the specimens were mounted in autopolymerized acrylic resin and tested in a universal testing machine and loaded at a crosshead speed of 0.5 mm/min at the metal-ceramic interface until fracture occurred. The average shear bond strength (MPa) was calculated by dividing the maximum fracture force (N) by the bonded surface of the specimens (mm2). The fracture patterns were observed microscopically and classified as adhesive, cohesive, or mixed. One-way ANOVA was used to determine differences between groups (α=.05). RESULTS: No significant differences were found among the shear bond strengths of specimens after 3, 4, 5, and 6 porcelain firings (P>.05). The mean bond strength of all groups ranged from 30 to 34 MPa. The fracture pattern of all specimens was mixed, indicating that multiple firings had no significant effect on the failure pattern. CONCLUSIONS: Multiple porcelain firings under controlled conditions had no significant effect on the fracture pattern or shear bond strength of porcelain to a presintered Co-Cr alloy.

Effects of number of firings and veneer thickness on the color and translucency of 2 different zirconia-based ceramic systems.

STATEMENT OF PROBLEM: Color matching between a zirconia-based ceramic restoration and a natural tooth is a common clinical challenge. PURPOSE: The purpose of this in vitro study was to investigate the effects of the number of firings, veneer thickness, and zirconia core translucency on the final color and translucency of zirconia-based ceramic restorations. MATERIAL AND METHODS: Sixty disk-shaped zirconia specimens (10×1 mm) were prepared in high and low translucencies (n=30 per translucency group). Each zirconia group was subdivided into 3 subgroups (n=10) veneered with ceramic layers of 0.5-, 1-, and 1.5-mm thicknesses. The specimens were then subjected to 1, 3, 5, and 7 firing times. Color and translucency parameters were measured by using a spectrophotometer. Data were analyzed by using multifactorial repeated measures ANOVA and subgroup analysis (α=.05). RESULTS: The number of firings affected the L*, a*, and b* values and translucency parameter in both zirconia-based systems with different veneer thicknesses (P<.05). Increasing the veneer thickness decreased the translucency parameter and increased the L*, a*, and b* values in both zirconia-based systems (P<.05). The color difference values (ΔE) were the highest between 1 and 3, 1 and 5, and 1 and 7 firings, and the lowest between 5 and 7 firings in both zirconia systems. CONCLUSIONS: Repeated firings and porcelain veneer thickness affected the final color and translucency of both zirconia systems and, consequently, adversely influenced the esthetic outcomes. Thus, these factors should be considered in the tooth preparation and laboratory phase.

Comparison of coronal sealing of flowable composite, resin-modified glass ionomer, and mineral trioxide aggregate in endodontically treated teeth: An in-vitro study.

Background: Coronal seal is one of the essential factors that affects the success of endodontic treatment and reinforces the apical seal. The intra-orifice barrier is an efficient alternative approach to decrease coronal leakage in endodontically treated teeth and various materials have been used for this purpose. This study aimed to compare the coronal sealing of flowable composite, resin-modified glass ionomer (RMGI), and mineral trioxide aggregate (MTA) in endodontically treated teeth. Materials and Methods: In this in vitro study, 35 single-canal canine teeth were divided into five groups, including flowable composite, RMGI, MTA, positive control, and negative control groups. The teeth were filled with restorative materials according to the factory's instructions. Afterward, the samples were immersed in 2% methylene blue dye solution for 1 week at 37°C and 100% humidity condition. Finally, the teeth were sectioned longitudinally and dye penetration was measured using a stereomicroscope with ×10. Data were analyzed with Kolmogorov-Smirnov and Kruskal-Wallis tests (α = 0.05). Results: The positive control group showed the highest amount of dye penetration compared to other groups (12.34 ± 0.46). Dye penetration in the MTA group was significantly lower (4.25 ± 0.31) compared to the RMGI group (5.94 ± 0.24) (P = 0.02). Moreover, while the dye penetration in the MTA group was lower than in the flowable composite group (5.65 ± 0.26), the difference was not statistically significant (P = 0.12). Conclusion: MTA reduces the coronal leakage and provides an acceptable coronal seal in endodontically treated teeth, especially compared to RMGI, and therefore, using MTA as an intra-orifice barrier increases the endodontic treatment success rate.

Evaluating the Color Matching Ability of a Smart Chromatic Technology-Based Composite Resin for Premolar Teeth Restoration.

Objectives: This study aims to evaluate the color-matching ability of OMNICHROMA composite, a single-shade composite, using the CIE L ∗ a ∗ b ∗ system and determining ΔE values. Materials and Methods: In this in vitro study, 30 intact premolar teeth were collected, cleaned, and disinfected with 0.5% thymol solution. The teeth were stored in distilled water at 37°C. A putty index calibrated the color assessment sites on buccal and lingual surfaces. Two cavities were prepared, one with 1.25 mm depth (enamel) and another with 2.25 mm depth (dentin), and restored using OMNICHROMA composite resin. The putty index measured the color of the cured composite, and ΔE between the composite and original tooth color was calculated. Statistical analysis: Data analysis included t-tests, correlation coefficients, and Fisher's exact test (α = 0.05). Results: The mean ΔE was 2.39 in enamel cavities and 2.32 in dentin cavities, both within the clinically acceptable range (<3.3). In enamel cavities, the composite color was darker than the tooth, shifting toward green and blue shades. In dentin cavities, the composite color was lighter than the tooth, with shifts toward green and yellow shades. Color matching was slightly better in dentin cavities, but the difference was not statistically significant (p=0.719). Conclusion: OMNICHROMA composite resin's color matching falls within the clinically acceptable range, unaffected by cavity depth.

Evaluation of the Bonding Shear Strength between Enamel and Dentin Feldspathic Porcelain and Two Different Monolithic Zirconia with Low and High Translucency.

Introduction: The utilization of ceramics in the field of dentistry has seen a significant rise owing to their esthetic appeal and excellent functional properties. The use of ceramics in the field of dentistry has witnessed a notable surge, driven by their appealing esthetics and exceptional functional attributes. Zirconia, distinguished by its exceptional mechanical strength, plays a pivotal role in the fabrication of posterior crowns and bridges. Among zirconia variants, monolithic zirconia stands out, where the entire restoration is crafted from zirconia material. In parallel, feldspathic porcelain, chosen for its remarkable resemblance to natural tooth enamel, represents another significant ceramic type. This study aims to evaluate the shear bond strength (SBS) between two types of monolithic zirconia with two types of feldspathic porcelain. Methods and Materials: Forty-four monolithic zirconia veneered discs with feldspathic porcelain were subjected to SBS testing. The dimensions of the discs were 7 mm in diameter and 5 mm in height (3 mm of zirconia and 2 mm of porcelain). Subsequently, the specimens were subjected to a universal testing machine at a speed of 0.5 mm/min until failure occurred. The type of failure was examined using scanning electron microscopy. One-way analysis of variance (ANOVA), two-way ANOVA, Fisher's test, and multiple Tukey comparisons were used as statistical analyses. Results: The highest SBS was achieved by the high-translucency monolithic zirconia with enamel porcelain group (18.81 ± 3.18 MPa) and the high-translucency monolithic zirconia with dentin porcelain group (17.89 ± 2.75 MPa), followed by the low-translucency monolithic zirconia with dentin porcelain group (15.04 ± 2.24 MPa) and the low-translucency monolithic zirconia with enamel porcelain group (14.33 ± 2.00 MPa), respectively. Additionally, the most common type of failure pattern observed was mixed, followed by adhesive failure. Conclusion: The translucency of the porcelain did not significantly affect SBS, while the type of monolithic zirconia used had a significant impact. Furthermore, there was no discernible relationship between the four groups in terms of the distribution of failure patterns.

Comparison of Stress and Strain Distribution Patterns in Canine Implant and Maxillary Bone in Three Occlusal Schemes Using Finite Element Analysis.

OBJECTIVES: This study aimed to compare the pattern of stress and strain distribution in canine implant and maxillary bone in the anterior group function (AGF), posterior group function (PGF), and canine guidance (CG) occlusal schemes by finite element analysis (FEA). MATERIAL AND METHODS: In this in vitro experimental study, a dental implant (10 × 4.1 mm) was inserted at the site of the maxillary canine in a model of the maxilla in Mimics software. The implant was scanned three-dimensionally and the data were transferred to SolidWorks software. The von Mises stress, shear stress, deformation, and strain were calculated in the AGF, PGF, and CG occlusal schemes by FEA. STATISTICAL ANALYSIS: Data were analyzed by ABAQUS software to calculate the stress transferred to the canine implant and maxillary bone in the three occlusal schemes. RESULTS: The maximum and minimum von Mises stress, elastic strain, shear stress, and deformation were noted in the AGF and PGF occlusal schemes, respectively, in all teeth. CONCLUSION: The PGF showed minimum von Mises stress, elastic strain, shear stress, and deformation in the canine implant and maxillary bone. Thus, it appears than the PGF is the best occlusal scheme for maxillary canine implant followed by the CG scheme.

Long-Term Clinical Outcomes of Single Crowns or Short Fixed Partial Dentures Supported by Short (≤6 mm) Dental Implants: A Systematic Review.

Long-term clinical outcomes of short dental implants (≤6 mm) supporting single crowns or short fixed partial dentures have been reported differently in different studies and need more clarification. This systematic study evaluated the rate of bone loss (BL), the durability of implants equal to or shorter than 6 mm supporting single crowns or short fixed partial dentures, and prosthetic-related side effects during 5 years of follow-up. Five databases (PubMed, MEDLINE, Scopus, Google Scholar, and Cochrane) were electronically and manually searched for longitudinal studies with a follow-up period of 5 years or more until January 2023. The study question was, "Does the implant equal to or shorter than 6 mm affect BL and survival rate of the implant-supported prosthesis after 5 years of follow-up?". From 752 identified articles, nine studies were selected for further evaluation. After 5 years of follow-up, most studies had more than 90% survival rate and the maximum BL was 0.54 mm. Still, in internal and external connections, these changes were not substantial. For example, screw loosening was the most common problem with implanted prostheses. Implants of 6 mm or shorter are a suitable treatment option in atrophic ridges with good durability and fewer side effects during a follow-up period of more than 5 years.

Tooth Graft: An Umbrella Overview.

This umbrella review aims to evaluate systematic/meta-analysis studies containing clinical evidence on tooth grafts as bone substitutes in the oral and maxillofacial regions. Using language restrictions and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, an electronic database search of PubMed, MEDLINE, Embase, Cochrane library, and Google Scholar was conducted, featuring published studies up until August 2022. All systematic/meta-analysis review articles relating to tooth graft materials were matched against the inclusion criteria. Two qualified researchers independently assessed the studies' inclusion or exclusion criteria and risk of bias, and a third investigator assisted in resolving ambiguities. A total of 81 systematic/meta-analysis studies, comprising 21 animal-controlled trials, 23 randomized controlled human trials, 23 prospective studies, and 14 retrospective studies, were selected for this study. A small risk of bias was observed in systematic studies/meta-analyses. In addition, the clinical evidence from the analysis of these studies revealed a low incidence of side effects. According to the current review, two systematic reviews indicated that autogenous bone grafting of prepared teeth might be as effective as other bone grafting materials. Four studies also mentioned autologous grafts as potential alternatives to autologous grafts, autogenous demineralized dentin (ADDM), engineered grafts, root blocks, and dental matrix. On the other hand, three systematic studies stated that more long-term research is needed to confirm their findings. Finally, given the importance of standardization and homogeneity of studies for clinical cases, it is advised to be used cautiously due to the risks of transplant rejection.

Herbal and nano-based herbal medicine: New insights into their therapeutic aspects against periodontitis.

Objective: Periodontitis is a type of prevalent chronic inflammatory disorder resulting in a failure in the function of tissues supporting the tooth, like gingiva, alveolar bone, and periodontal ligament. Although antibiotic therapy is a common therapy for periodontitis cases, this approach can cause some adverse effects in these patients. Thus, finding an effective curative option with low side effects is still a puzzle. Materials and Methods: This narrative review was conducted on the effects of herbal and nano-based herbal medicine against periodontitis by searching different databases such as Google Scholar, PubMed, Scopus, Web of Science, Science Direct, and Scientific Information Databases. Results: According to published studies, some popular herbal formulations, such as Aloe vera, curcumin, Melaleuca alternifolia, and Scutellaria baicalensis Georgi, can be effective in periodontitis treatment. However, these herbal products may be accompanied by some pharmacological limitations, such as poor bioavailability, instability, and weak water solubility. On the other hand, harnessing nano-based herbal formulations can elevate the bioavailability, diminish toxicity, and omit repeated administration of drugs. Conclusion: Herbal and nano-based herbal products can create a good chance to treat periodontitis efficiently.

Comparative assessment of flexural strength of monolithic zirconia with different thicknesses and two sintering techniques.

OBJECTIVES: This study aimed to compare the flexural strength of monolithic zirconia with different thicknesses and two sintering techniques. MATERIALS AND METHODS: This in vitro, experimental study was conducted on 28 monolithic zirconia discs with 10 mm diameter and 0.5 (n = 14) and 1.2 mm (n = 14) thickness. Each group was divided into two subgroups (n = 7) for fast (60 min) and conventional (120 min) sintering at 1450°C. After sintering, the specimens were thermocycled and their flexural strength was measured by piston-on-3-balls technique in a universal testing machine (0.5 mm/min, 1.2 mm pin diameter). Data were analyzed by the Weibull test, one-way analysis of variance, and Tukey's test (α = .05). RESULTS: The flexural strength of specimens with 1.2 mm thickness was significantly higher than that of specimens with 0.5 mm thickness (p < .05). The flexural strength of 1.2 mm/120-min group was slightly, but not significantly, higher than that of 1.2 mm/60-min group (p > .05). The flexural strength of 0.5 mm/120-min group was slightly, but not significantly, higher than that of 0.5 mm/60-min group (p > .05). CONCLUSION: The increase in thickness of monolithic zirconia increases its flexural strength; however, increasing the sintering time appears to have no significant effect on the flexural strength of monolithic zirconia.

Stress Distribution in 5-Unit Fixed Partial Dentures with a Pier Abutment and Rigid and Nonrigid Connectors with Two Different Occlusal Schemes: A Three-Dimensional Finite Element Analysis.

Objectives: This study aimed to assess stress distribution in 5-unit fixed partial dentures (FPDs) with a pier abutment and rigid (RC) and nonrigid connectors (NRCs) with the canine rise and group function occlusal schemes by finite element analysis (FEA). Materials and Methods: In this FEA study, a geometrical model of the maxilla with natural teeth and periodontal ligament (PDL) was three-dimensionally designed and meshed by ANSYS and Pro/Engineer software programs. A 5-unit FPD was then designed to replace the lost first premolar and first molar teeth; the second premolar served as a pier abutment, and the canine and second molar served as terminal abutments. Two FPDs were designed with RC and NRC. Each FPD was analyzed with the canine rise and group function occlusal schemes (a total of 4 models). The first and second molars (180 N), premolars (120 N), and canine (80 N) teeth were subjected to progressive vertical and oblique (12-degree) loads, and maximum von Mises stress and strain in teeth and connectors were calculated for each model. Results: The models had 73704 elements and 137732 nodes. The connector design and occlusal scheme had significant effects on stress distribution in FPDs. The highest von Mises stress (73.035 MPa) was recorded in FPD with RC and group function occlusal scheme. The lowest von Mises stress (0.004 MPa) was recorded in FPD with NRC and canine rise occlusal scheme. Conclusion: Oblique forces created greater stress, and FPD with NRC and canine rise occlusal scheme decreased stress in FPD and increased stress in the tooth crown.

Effectiveness of Different Antimicrobial Agents on Malodor Prevention in Two-Stage Dental Implants: A Double-Blinded Randomized Clinical Trial.

OBJECTIVE: Opening of a healing abutment in two-stage implant systems is usually followed by a bad smell. Previous studies have found that presence of bacteria in microleakages of the implant-abutment interface results in further malodor. However, studies focusing on preventive treatments for this issue are scarce. Therefore, the aim of this study is to evaluate the effectiveness of two antimicrobial agents on prevention of malodor followed by opening the healing abutments. MATERIALS AND METHODS: Current double-blinded randomized clinical trial was performed on 51 eligible patients who were referred for their exposure surgery. They were divided equally into three parallel groups. In two groups, either chlorhexidine or tetracycline was added to the internal surface of the fixtures before screwing the healing abutments. One group did not receive any intervention. Three to 4 weeks later malodor was scored by sniffing the healing abutments immediately after uncovering them (odorless = 0/odor = 1). The three groups were then compared regarding malodor scores. RESULTS: Our findings showed that malodor was more frequent in the control group (58.82%) in comparison with groups of intervention (17.65 and 23.53%). There was a statistically significant difference between malodor in patients in whom antimicrobial agents (chlorhexidine and tetracycline) were used in their implants and the control group (p-value = 0.023). However, malodor in the chlorhexidine group and tetracycline group did not show any significant difference (p-value = 1). CONCLUSION: Based upon the data from this study, it appears that local antimicrobial agents including chlorhexidine and tetracycline result in less malodor production within the implant-abutment interface. CLINICAL SIGNIFICANCE: A specific type of malodor is commonly seen after opening the healing abutment of a two-stage dental implant. Not only this issue is noticed by the dentist, but also annoyed the patient. Using local antimicrobial agents in the fixtures is likely to be a simple, easily applicable solution that satisfies both patients and dentists, and eliminates the possibility of further inflammation.