Antibacterial Effects of MicroRepair®BIOMA-Based Toothpaste and Chewing Gum on Orthodontic Elastics Contaminated In Vitro with Saliva from Healthy Donors: A Pilot Study

Inhibitory Effect of Adsorption of Streptococcus mutans onto Scallop-Derived Hydroxyapatite

Hydroxyapatite adsorbs various substances, but little is known about the effects on oral bacteria of adsorption onto hydroxyapatite derived from scallop shells. In the present study, we analyzed the effects of adsorption of Streptococcus mutans onto scallop-derived hydroxyapatite. When scallop-derived hydroxyapatite was mixed with S. mutans, a high proportion of the bacterial cells adsorbed onto the hydroxyapatite in a time-dependent manner. An RNA sequencing analysis of S. mutans adsorbed onto hydroxyapatite showed that the upregulation of genes resulted in abnormalities in pathways involved in glycogen and histidine metabolism and biosynthesis compared with cells in the absence of hydroxyapatite. S. mutans adsorbed onto hydroxyapatite was not killed, but the growth of the bacteria was inhibited. Electron microscopy showed morphological changes in S. mutans cells adsorbed onto hydroxyapatite. Our results suggest that hydroxyapatite derived from scallop shells showed a high adsorption ability for S. mutans. This hydroxyapatite also caused changes in gene expression related to the metabolic and biosynthetic processes, including the glycogen and histidine of S. mutans, which may result in a morphological change in the surface layer and the inhibition of the growth of the bacteria.

Anti-fungal efficacy of Miswak Extract (Salvadora Persica) and commercial cleaner against Candida albicans on heat cured polymethylmethacrylate denture base

AIM

The aim of the study was to compare the antifungal efficacy between commercial cleaner (Corega) and Miswak extract (Salvadora persica) against Candida albicans on heat cured Polymethyl methacrylate (PMMA) acrylic denture base resin.

MATERIALS AND METHODS

Forty-eight samples of heat cured PMMA acrylic denture base resin were fabircated in the study. The sterile acrylic resin specimens were immersed in standardized cell suspension of Candida albicans and incubated for 60 min at 370°C for cell adhesion and 2 h at 370°C for biofilm formation. After 24 h biofilm was evaluated by cell viability (CFUs) on SDA and cell counting of Candida albicans under light microscope at 400× magnification. The fungicidal effect of commercial cleaner and Miswak extract on Candida albicans biofilm was then evaluated by colony-forming units on SDA and cell counting under light microscope at 400× magnification.

RESULTS

Screening test agar disk-diffusion assay showed mean inhibitory zone of 3 mm for commercial cleaner as compared to Miswak extract, which showed mean inhibitory zone of 2 and 1 mm for different concentrations. Broth microdilution method showed 31 mg/ml MIC and 62.5 mg/ml Minimal Fungicidal Concentration (MFC) values for commercial cleaner as compared to Miswak extract that showed 125 mg/ml MIC and 250 mg/ml MFC values against Candida albicans. A significant difference (p < 0.05) was observed between pre and post treatment of both commercial cleaner and Miswak extract, for CFUs and cell count for Candida albicans.

CONCLUSION

Commercial denture cleaner (Corega) showed better antifungal (C albicans) activity than Miswak extract (Salvadora persica) on heat cured PMMA acrylic denture base resin.

Novel Options to Counteract Oral Biofilm Formation: In Vitro Evidence

Biofilm production on biotic and abiotic surfaces is crucial in the pathogenesis of most infections, particularly those occurring in the oral cavity. Its prevention and/or control may greatly facilitate the management of patients with oral diseases. Here, the antibiofilm activity of a biomimetic hydroxyapatite and a natural compound, MicroRepair (MicroR) and pomegranate (PomeGr), respectively, was assessed. By luminescence/fluorescence-based assays, Pseudomonas aeruginosa (P. aeruginosa), Staphylococcus aureus (S. aureus) and Candida albicans (C. albicans) were tested for biofilm production in the presence of MicroR and/or PomeGr. We found that both MicroR and PomeGr could affected biofilm production; however, the efficacy of the two, given alone or in combination, varied according to the microbial agent considered. These data open to clinical studies aimed at defining the most efficacious protocols to counteract oral biofilm-associated infections.

The use of monophasic implants as an alternative of implant-prosthetic rehabilitation in the posterior maxilla with no sinus lift

BACKGROUND

Over the years, numerous studies and advanced technologies about dental implants have been evolved from the traditional two-stage procedure to immediate loading. Implants located in the posterior maxillary region allow to achieve an appropriate prosthetic support. The aim of this work was to solve the atrophied posterior maxilla, through monophasic implants with flapless technique and intraoral electro-welding.

METHODS

In this study were enrolled 120 patients between 20 and 68 years old (mean age of 34.2 years), where females predominate with 53.1% compared to 46.9% males. The patients were presented at the Oral Surgery Clinic of the Aldent University (Tirana, Albania), for a period 2009-2019. Briefly, 310 monophasic implants were placed, TRAMONTE type (Milan, Italy), to the posterior maxilla thus avoiding the sinus, with dense and wide threads, of different lengths and widths. The surgical technique was minimally invasive, flapless one. Data were expressed as mean + standard error (SEM) of all the radiographic outcomes obtained; and as statistical analysis was used the Student's t-test. P<0.5 and P<0.05, were considered significant.

RESULTS

A part of the patients were hypertensive and type 2 diabetic, then a negligible part were smokers, also a lack of oral hygiene was observed in 40% of cases. After 5 years of observation, it appeared that 95.9% of the implants were successful. Furthermore, the mesial and distal bone loss during the first three years was 0.1 mm, while after 5 years no continuation of bone loss was observed.

CONCLUSIONS

The application of monophasic implants must be performed according to approved protocols, considering the conditions of the posterior maxillary region, obtaining in this way a safe dental implantation.

Effectiveness of Two Different Fluoride-Based Agents in the Treatment of Dentin Hypersensitivity: A Prospective Clinical Trial

Hyperesthesia is related to increased sensitivity of dental tissues to mechanical, chemical and thermal stimuli. The aim of this prospective clinical trial was to compare the effectiveness of a calcium-fluoride-forming agent (Tiefenfluorid®, Humanchemie GmbH, Alfeld, Germany) with that of a fluoride varnish (EnamelastTM, Ultradent Inc., Cologne, Germany) in the treatment of dental hyperesthesia in adult patients. In total, 176 individuals (106 females and 70 males, aged 18-59 years old) diagnosed with dental hyperesthesia (DH) were enrolled. The main clinical symptoms were hyperesthesia from coldness and sweetness during chewing; the types of clinical lesions were also determined and recorded. The patients were selected randomly and divided into two groups: (i) the first group of 96 patients was treated with Tiefenfluorid® applied in three appointments at 7-day intervals; (ii) the second group of 80 patients was treated with EnamelastTM, applied seven times at 7-day intervals. All the patients were recalled 7 days, 14 days, 1 month, 3 months, and 6 months from the last application. At the baseline and during every follow-up visit, the DH was measured with a pulp tester. A random intercept/random slope model was used to evaluate the effect of the treatment, at various times with respect to the initial diagnosis. Within the limits of the present study, Tiefenfluorid® was more effective than EnamelastTM against DH in that it provided long-lasting results, with a significant improvement still detected at the latest 6-month follow-up.

White Spots Prevalence and Tooth Brush Habits during Orthodontic Treatment

White spots (WS) are one of the most undesirable side effects in patients undergoing orthodontic therapy and are usually located around bracket bases and even detected under the molar bands. The aim of the present cross-sectional study was to evaluate the WS lesion during orthodontic therapy and the correlation between WS and oral hygiene habits. Patients requiring orthodontic treatment with a fixed appliance were screened for the inclusion/exclusion criteria, and 74 subjects were finally enrolled. Each patient received three examinations: at T0, the day of the application of the fixed appliance; at T1, three months later; and at T2, six months after treatment start. After calculating descriptive statistics, differences between groups were evaluated with an independent sample t-test. The first type error was set as p ≤ 0.01. The observed prevalence of WS lesions was 59.5% on T1 and 60.8% on T2. The most affected teeth result to be upper molars, lower left first molar, upper right central incisor and upper left lateral incisor, upper right canine, upper left first premolar, and lower right first molar. A higher frequency of daily tooth brushing was accompanied by a lower prevalence of WS. No significant effect of sex was observed.

Multi-Omics Reveals the Inhibition of Lactiplantibacillus plantarum CCFM8724 in Streptococcus mutans-Candida albicans Mixed-Species Biofilms

Lactiplantibacillus plantarum CCFM8724 is a probiotic with the potential to prevent dental caries in vitro and in vivo. To explore the effects of this probiotic at inhibiting Streptococcus mutans-Candida albicans mixed-species biofilm and preventing dental caries, multi-omics, including metabolomics and transcriptomics, was used to investigate the regulation of small-molecule metabolism during biofilm formation and the gene expression in the mixed-species biofilm. Metabolomic analysis revealed that some carbohydrates related to biofilm formation, such as sucrose, was detected at lower levels due to the treatment with the L. plantarum supernatant. Some sugar alcohols, such as xylitol and sorbitol, were detected at higher levels, which may have inhibited the growth of S. mutans. In transcriptomic analysis, the expression of the virulence genes of C. albicans, such as those that code agglutinin-like sequence (Als) proteins, was affected. In addition, metabolomics coupled with a Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis and RNA-seq revealed that the L. plantarum supernatant had an active role in sugar metabolism during the formation of the S. mutans-C. albicans mixed-species biofilm, and the L. plantarum supernatant was also related to carbohydrate utilization, glucan biosynthesis, and mycelium formation. Hence, L. plantarum CCFM8724 decreased the mixed-species biofilm mass from the perspective of gene expression and metabolic reprogramming. Our results provide a rationale for evaluating L. plantarum CCFM8724 as a potential oral probiotic for inhibiting cariogenic pathogen biofilm formation and improving dental caries.

Factors Affecting Dietary Improvements in Elderly Residents of Long-Term Care Institutions Receiving Domiciliary Dental Care

Background: Oral disabilities occur due to tooth loss. This study aimed to investigate oral and systemic factors related to diet in elderly residents receiving domiciliary dental care. Methods: The subjects were 74 consenting residents. Survey items included whether subjects could eat independently and diet type. Subjects were examined by the dentist for the number of teeth, occlusal support index, and wearing dentures. Contingency table analysis was performed to determine what levels of decline in general and oral functions led to difficulties eating a normal diet. Results: There was a significant difference in the mean number of activities of daily living (ADL) requiring assistance evident between subjects eating a normal diet and those eating fluid boiled rice (p < 0.01). A comparison of occlusal support and diet type showed that most subjects who ate a soft diet or gruel had no occlusal support. Almost all subjects who ate a normal diet wore dentures. However, only 38% of subjects eating a soft diet and 40% of those eating gruel did wear dentures; both group differences were significant (p < 0.01). Conclusions: Future studies need to further investigate oral factors related to the type of diet and their relationships to domiciliary dental care in older adults.

Novel Approach to Dental Biofilm Management through Guided Biofilm Therapy (GBT): A Review

Dental biofilm plays a very crucial role in the etiopathogenesis of periodontal andperi-implant diseases. Over the past decade, tremendous research has been carried outto know the structure of biofilm and the mechanism by which it causes the destruction of supporting tissues of tooth or implant. Periodontal or peri-implant therapy usually begins with primarily removing thebiofilm and is considered as non-surgical mechanical debridement. Although scaling and root planing (SRP) is regarded as a gold standard for mechanical plaque debridement, various other means of biofilm removal have constantly been evolving. These may vary from different scaling systems such as vector systems to decontamination of pockets with LASER therapy. Nowadays, a new concept has emerged known as “guided biofilm therapy” (GBT). It is beneficial in removing the biofilm around the tooth and implant structures, resulting in better or comparable clinical outcomes than SRP. These results were substantiated with the reduction in the microbial load as well as the reduction in the inflammatory cytokines. This review will highlight the various aspects of GBT used in periodontal and peri-implant disease.