Unlocking the potential of probiotic administration in caries management: a systematic review

BACKGROUND

The use of prebiotics and/or probiotic bacteria with the potential to modulate the oral ecosystem may play an important role in the prevention and management of dental caries. To assess the evidence of the potential of pre/probiotics both in the prevention and treatment of dental caries, we focused on the PICO question "In individuals with caries, after probiotic administration, is there an improvement in outcomes directly related to caries risk and development?".

METHODS

An extensive systematic search was conducted in electronic databases PubMed, Web of Science, Scopus and Cochrane, to identify articles with relevant data. This systematic review included trials performed in Humans; published in English; including the observation of patients with caries, with clear indication of the probiotic used and measuring the outcomes directly involved with the cariogenic process, including the quantification of bacteria with cariogenic potential. To evaluate the methodological quality of the studies, the critical assessment tool from the Joanna Briggs Institute was used.

RESULTS

Eight hundred and fifty articles, potentially relevant, were identified. Following PRISMA guidelines 14 articles were included in this systematic review. Outcomes such as reduction of cariogenic microorganism counts, salivary pH, buffer capacity, and caries activity were assessed. The probiotic most often referred with beneficial results in dental caries outcomes is Lacticaseibacillus rhamnosus. Regarding the most used administration vehicle, in studies with positive effects on the caries management, probiotic supplemented milk could be considered the best administration vehicle.

CONCLUSIONS

Evidence suggests a beneficial effect of probiotic supplemented milk (Lacticaseibacillus rhamnosus) as an adjuvant for caries prevention and management. However, comparable evidence is scarce and better designed and comparable studies are needed.

White spot lesions: diagnosis and treatment - a systematic review

BACKGROUND

White spot lesions represent the first stage of caries and their prevalence has been increasing in recent years, particularly in patients undergoing orthodontic treatment. DIferential diagnosis and lesion activity are essential to decide on the clinical approaches to treatment. The aim of this study is to understand if the new diagnostic tools such as fluorescence, microradiography and computed microtomography have the potential to change the conventional treatment of white spots".

METHODS

A systematic search of available studies in the literature was carried out, using PRISMA guidelines, in Pubmed and Scopus electronic databases and manually to identify relevant articles to answer the PICO question: "Do the new diagnostic tools have the potential to change the conventional treatment of white spots?". This systematic review included randomized controlled trials (RCT), cross-sectional and longitudinal studies complying with the following inclusion criteria: (i) studies in humans, (ii) studies about white spot lesions, (iii) studies published between 2012 and 2023, (iv) studies having both diagnosis and treatment and (v) studies with full text available. In this review we excluded other systematic reviews of clinical trials and in vitro studies. The RoB tool was used to assess the risk of bias.

RESULTS

The systematic literature search identified 143 potentially relevant references, which after applying the exclusion criteria, resulted in 20 articles. Regarding diagnostic methods, most articles found were based on conventional methods of visual examination (n:10) or fluorescence (n:7). The least referenced diagnostic techniques were based on the use of clinical photographs (n:2), cross-sectional microradiography (n:1) and computed microtomography (n:1). The use of DIAGNOdent was reported by 3 in vitro studies. With regard to therapies, most studies reported the use of infiltrating resin (n:7) and fluoride-based products (n:5). Other studies have reported the use of self-assembling peptide P11-4 (n:1), home care (n:1), casein phosphopeptide-amorphous calcium phosphate (n:2) and hydrochloric acid (n:1). Combination therapies were also considered.

CONCLUSION

Diagnostic tool does not have the potential to change the form of treatment, whether it is a conventional method or a more differentiated one.

The Interference of Age and Gender on Smile Characterization Analyzed on Six Parameters: A Clinical-Photographic Pilot Study

Background and Objective: This study aimed to evaluate six smile-esthetic parameters (deviation of the upper dental midline from the facial midline, upper lip curvature, smile line, smile arch, smile width, and shape of the maxillary central incisors), correlating them with age and gender. Materials and methods: Caucasian individuals (N = 114) were grouped by gender (male and female) and age (group I—18 to 30 years old; group II—31 to 50 years old; and group III—over 50 years old). Using a digital camera, extra and intraoral pictures were taken to analyze the variables above-mentioned. The data were statistically evaluated, considering a significance level of p < 0.05. Results: Most participants found deviations of the upper dental midline, straight upper lip curvature, and the medium smile line coincided with the facial midline. The parallel smile arch exposing 9 to 11 upper teeth, the absence of exposure of lower teeth when smiling, and oval upper incisors were prevalent parameters. Regarding gender, significant results were found for the curvature of the upper lip (p = 0.049), the smile arch (p = 0.001), and the shape of the upper central incisors (p = 0.004). For age, the association with the curvature of the upper lip (p = 0.032), the smile line (p = 0.001), the smile arch (p = 0.007), the width of the smile exposing lower teeth (p = 0.002), and the shape of the upper central incisors (0.012) were significant. Conclusions: Within this study’s limitations, gender and age affect the anterior teeth shape and upper lip curves; gender and age did not influence the coincidence between dental and facial midlines.

Lipopolysaccharide injection induces rapid decrease of hypothalamic GnRH mRNA and peptide, but does not affect GnIH in zebra finches

Lipopolysaccharide (LPS) is frequently used experimentally to mimic acute infection. Through activation of the host's immune response, an LPS injection has profound effects on the adrenocortical response to stress and on behaviors including reduction in activity, water and food intake, and libido. These behavioral changes occurring during infection are collectively called "sickness behavior." It is thought that adoption of sickness behavior reallocates energy from other fitness-enhancing activities, such as reproduction, for use in the immune response. Although the behavioral effects of LPS treatment are well-known, less information is available regarding the effects of LPS on the brain in terms of controlling reproductive behavior, specifically concerning a newly discovered neuropeptide, gonadotropin-inhibitory hormone (GnIH). This study investigated the effects of an LPS injection on the behavior and the hypothalamic neuropeptides controlling reproduction [GnIH and gonadotropin-releasing hormone (GnRH)] of zebra finches (Taeniopygia guttata). Overall, there was a decrease in activity in birds injected with LPS. The number of GnRH-immunoreactive neurons was significantly reduced in birds injected with LPS when compared to controls, while the number of GnIH-releasing neurons remained unchanged. At the level of gene expression, a similar pattern was found: there was reduced expression of GnRH mRNA in LPS-injected animals, whereas GnIH expression remained unchanged. Plasma testosterone did not change significantly in LPS-injected animals, nor did plasma corticosterone. Taken together, these results indicate a rapid (within 3h) inhibition of the reproductive axis during an immune challenge mimicking an infection, specifically acting on the GnRH system. The present study expands our knowledge on the interaction between the immune system and the reproductive system.