Clinical effects of Lactobacillus reuteri probiotic in chronic periodontitis - a systematic review

OBJECTIVE

This systematic review examines the effectiveness of Lactobacillus reuteri as an adjunct to scaling and root planing in the treatment of chronic periodontitis.

MATERIALS AND METHODS

Scopus, PubMed, and Web of Science databases were searched according to specific inclusion and exclusion criteria in October 2022. Randomized control trials that evaluated the effects of Lactobacillus reuteri in patients with periodontitis were included. The primary outcome was pocket depth and clinical attachment levels, while the secondary outcome considered was bleeding on probing, microbial levels, and gingival index score. Study quality was assessed based on the Cochrane Handbook for Systematic Reviews of Interventions and the ROB2 tool.

RESULTS

A total of eleven studies that examined 369 subjects were included in the review. Adults in the age group of 18-70 years of age suffering from chronic periodontitis were evaluated. Eight out of the eleven studies reported statistically significant improvement in the intergroup pocket depths, whereas seven studies showed a statistically significant reduction in the clinical attachment levels in the probiotic group. Three studies showed no significant improvement in the pocket depth levels in the probiotic group as compared to the controls. Four studies showed no significant reduction in clinical attachment levels between the two groups. The overall risk of bias was high in four studies, while seven studies reported some concerns about the risk of bias.

CONCLUSIONS

Based on the limited evidence available, the adjunctive use of Lactobacillus reuteri to scaling and root planing may provide some additional benefit in improving periodontal parameters.

Diode laser targeting red-complex bacteria in periodontitis: a systematic review

OBJECTIVE

This systematic review examines the effectiveness of diode laser irradiation in reducing the levels of red complex bacteria as well as periodontal parameters of pocket depth and clinical attachment level.

MATERIALS AND METHODS

We conducted electronic searches across databases such as Scopus, Embase, Medline, and Web of Science databases in July 2022. Randomized controlled trials that evaluated the reduction of red-complex bacteria in patients with periodontitis using diode lasers were included. The primary focus was the reduction in the microbial count of red complex bacteria, whereas probing depth and attachment level were considered secondary outcomes. Articles in languages other than English were excluded. Study quality was assessed based on the Cochrane Handbook for Systematic Reviews of Interventions and the ROB2 tool.

RESULTS

After searching the databases, eight independent studies were included, with a sample size of 210 subjects. The average age group of the study population was 30-60 years, and there was a lack of consensus on the antimicrobial effect of diode lasers. Out of the eight studies, four studies reported no significant difference in the levels of red complex bacteria before and after laser application. Three studies reported significantly lower levels of red complex bacteria in the intergroup comparison. One study reported that laser had no significant effect on intergroup bacterial levels. The combination of diode laser irradiation with scaling reduced the count of red complex bacteria and improved the clinical parameters, although not significantly.

CONCLUSIONS

Based on the limited evidence available, the adjunctive use of diode laser for scaling and root planning may provide some additional benefit in terms of reduction of red complex bacterial count and clinical parameters. Further well-designed trials and the use of objective measures are necessary before outlining universal guidelines for best practice. The adjunctive use of diode laser in non-surgical periodontal therapy may provide a reduction in the red complex microbial count and improvement in clinical parameters, decreasing the need for periodontal surgery.

Success rate of immediately loaded implants in the posterior zone

Dental implants are considered an ideal treatment for a missing single tooth. Immediate loading of implants can hasten the procedure, providing comfort to the patients. Recently, immediate loading of implants has gained much importance as it helps hasten the procedure and provides more comfort to patients. A previous systematic review published 5 years ago compared the success rates between immediate and conventional loading. There are several factors that influence the success rate of implants that were not discussed in detail in the previous review. Hence, the present systematic review is done to report differences in the outcomes from single implant restorations of missing teeth in the posterior region in patients who were subjected to immediate loading and conventional loading. A follow up for 1 year was done. Electronic databases of Medline, Scopus, and Web of Science were searched for publications in the English Language during May 2021. The search results yielded 306 articles, out of which 225 were excluded based on title and abstract screening. Screening of the remaining 81 full text articles yielded 14 original research articles that satisfied the predefined inclusion criteria. Meta analysis was not possible due to the heterogeneity of the data. The overall success rate of the immediate loading of a single implant is 94.31%. Implants in the maxillary region had a higher survival rate than those in the mandibular region. The age range between 18 and 80 years showed good prognosis and outcomes in older individuals. Good oral hygiene was emphasized for all patients to prevent any secondary conditions or delays in healing.

A split-mouth randomized controlled trial to compare the rate of canine retraction after a soft tissue procedure compared against a corticotomy procedure for accelerated tooth movement

Background and Aim

Various methods to accelerate the orthodontic tooth movement have been used, among which corticotomy is considered to be the most common one. The suggested reasoning for such acceleration was the regional acceleratory phenomenon (RAP). Since the RAP is a property of both the hard and soft tissues, we designed a soft tissue flap procedure to compare the effects with the conventional corticotomy procedure. A split-mouth study was conducted where the two procedures were assessed in a single participant.

Patients and Methods

The total sample size was calculated to be 40 with 20 participants in each group. The rate of tooth movement was the primary outcome measure, and the secondary outcomes were dentoalveolar changes, which were studied in both the conventional corticotomy and the flap-only procedure based on a cone-beam computed tomography (CBCT) wherein the alveolar bone density (BD) around canines, tipping, and rotational changes in canines, premolars, and molars were assessed.

Results

Corticotomy resulted in greater canine angulation, lesser canine rotation and premolar rotation, and greater molar rotation compared with flap elevation, but these differences were statistically insignificant.

Conclusion

Though the corticotomy resulted in higher BD, the differences were statistically insignificant. There was no significant difference in the rate of space closure assessed by the two techniques compared.

Effect of prosthetic framework material, cantilever length and opposing arch on peri-implant strain in an all-on-four implant prostheses

Aim

To evaluate the effect of prosthetic framework material and cantilever length on peri-implant strain in mandibular all-on-four implant-supported prostheses with different types of arch antagonist forces.

Materials and Methods

Models simulating a completely edentulous mandibular arch fabricated in heat-cured acrylic resin were used. On the acrylic models, four implants were placed at regions 34, 32, 42, and 44 simulating all-on-four implant placements. Implant-supported screw-retained fixed prosthesis frameworks were fabricated using three different materials (cobalt-chromium, zirconia, and polyetheretherketone) and with three different cantilever lengths (zero mm, 15 mm, and 25 mm). Strain gauges were attached on the model at the buccal and lingual positions of each implant. Forces simulating opposing natural dentition, conventional complete denture, and the parafunctional habit were applied to the models. The peri-implant strain in each strain gauge was recorded.

Results

Least peri-implant strains (67 microstrains) were observed when forces simulating conventional complete dentures were applied on the models and the highest peri-implant strains (9091 microstrains) were observed when forces simulating parafunctional habit were applied. One-way ANOVA test followed by Tukey's post hoc analysis was performed to compare the mean deformation scores between different materials at 50 N load. The level of significance [P-value] was set at P < 0.05. Tests showed significant differences between zero mm and the other types in all the different materials, and also between 1.5 x AP and 2.5 x AP for Zirconia and Peek material at P = 0.02 & P = .008, respectively. The results showed that the type of framework material, cantilever length, and occlusal forces from the opposing arch influence the peri-implant strain in the bone in all-on-four implant-supported prostheses.

Conclusion

Rehabilitation of a single, completely edentulous arch with implant-supported prostheses should consider the situation of the opposing arch. The choice of framework material, as well as the cantilever length, should be altered based on the forces from the opposing arch.

Comparison of biochemical markers of bone metabolism between conventional labial and lingual fixed orthodontic appliances

Objectives

The applied orthodontic force causes remodeling of the periodontium through the selective release of cytokines causing resorption of bone, enabling controlled movement of the tooth. This study compared the cytokine profile between patients treated with conventional labial and lingual fixed orthodontic appliances.

Patients and Methods

The study included 80 patients in need of orthodontic treatment, out of which 40 patients were treated by the labial fixed appliance and 40 by the lingual fixed appliance. Gingival crevicular fluid (GCF) specimens were gathered from both the groups using a microcapillary pipette. The samples were collected at the beginning of the treatment and after 21 days. Enzyme-linked immunosorbent assay was performed to evaluate the cytokine levels.

Results

Interleukin (IL)-1α, 1β, 2, 8, and tumor necrosis factor-alpha (TNF-α) levels were significantly high (P < 0.001) in GCF of participants treated with conventional labial fixed appliance. IL-1α, 1β, 2, 6, 8, and TNF-α levels were significantly high (P < 0.001) in GCF of participants treated by the lingual fixed appliance. The concentrations of TNF-α and IL-1β were increased higher than other cytokines in both the treatment groups.

Conclusion

Overall, the lingual fixed appliance had higher cytokine levels than a labial fixed appliance. Analyzing the GCF cytokine levels during orthodontic treatment could provide an ideal platform for monitoring the progress of the treatment.

Comparative evaluation of fracture toughness and marginal adaptation of two restorative materials in nonendodontically and endodontically treated teeth: An in vitro study

Objective

To evaluate and compare the fracture resistance and marginal adaptation of Zirconomer and bulk fill posterior restorative material (Surefil SDR) in nonendodontically and endodontically treated teeth.

Materials and Methods

The sample consisted of 52 caries-free extracted human premolars which were individually mounted in polyvinyl chloride (PVC) ring filled with acrylic resin up to 1.0 mm below the cementoenamel junction. The teeth were then divided into four groups according to the restorative material used as group I: Zirconomer + Operative only, Group II: Zirconomer + Endodontic treatment, Group III: SDR + Operative, and Group IV: SDR + Endodontic treatment. Fracture strength was tested using a universal testing machine and was expressed in Newtons. The marginal gap was measured at its maximum using a scanning electron microscope and expressed in micrometers. One-way analysis of variance followed by Tukey's post hoc test was used to compare the mean fracture resistance (N) and marginal adaptation (μm) between the four groups. Statistical significance was determined at α = 0.05.

Results

Group 3 exhibited significantly highest mean fracture resistance than Group 1 (P < 0.001), Group 2 (P < 0.001), and Group 4 (P < 0.001). Group 4 had significantly higher mean fracture resistance than Group 1 (P = 0.008) and Group 2 (P < 0.001). Group 1 exhibited significantly highest mean marginal gap than Group 3 (P < 0.001) and Group 4 (P < 0.001). Group 2 had a significantly higher mean marginal gap than Group 3 (P < 0.001) and Group 4 (P < 0.001).

Conclusion

The fracture resistance and marginal adaptation of Zirconomer are significantly lower than Surefil SDR in both nonendodontically and endodontically treated teeth.