A Systematic Review of the Effect of Oral Rinsing with H2O2 on Clinical and Microbiological Parameters Related to Plaque, Gingivitis, and Microbes

Antimicrobial Mouthwashes: An Overview of Mechanisms-What Do We Still Need to Know?

This narrative literature review is the first in a 6-section supplement on the role of mouthwashes in oral care. This introduction briefly summarises current knowledge on antimicrobial mechanisms, relating to some of the most common over-the-counter mouthwash products available worldwide: chlorhexidine, hydrogen peroxide, cetylpyridinium chloride, povidone iodine, and essential oils. The aim of this first article is to describe how mouthwashes "kill" pathogenic microbes when used adjunctively and thus provide a basis for their widespread use to manage key oral diseases, namely caries, gingivitis, and periodontal disease. This article therefore sets the scene for subsequent, more detailed exploration of mouthwashes regarding their clinical effectiveness, impact on the oral microbiome, and possible effects on systemic health as well as natural alternatives and future directions. Other than the clinical effectiveness (for certain agents) of mouthwashes, on many topics there remains insufficient evidence for systematic review or formulation of robust national guidelines. The supplement, therefore, compiled by an international task team, is aimed at general dental practitioners across the globe, as an easy-to-read guide for helping to advise patients on mouthwash use based on the current best available evidence.

The In Vitro Effect of Laser Irradiation (Er:YAG and CO2) and Chemical Reagents (Hydrogen Peroxide, Sodium Hypochlorite, Chlorhexidine, or Sodium Fluoride) Alone or in Combination on Reducing Root Caries Bacteria

(1) Lasers have been used for the treatment of dentinal hypersensitivity and bacterial reductions in periodontology. The purpose of this in vitro study was to evaluate the effect of Carbon Dioxide (CO₂) and Erbium-doped Yttrium Aluminum Garnet (Er:YAG) lasers with chlorhexidine (CHX), hydrogen peroxide (H₂O₂), sodium hypochlorite (NaOCl), or sodium fluoride (NaF) on the viability of oral bacteria associated with root caries. (2) Streptococcus mutans, Streptococcus sanguinis, and Enterococcus faecalis were grown in Brain Heart Infusion (BHI) broth, diluted to an OD660 of 0.5, and treated with antiseptics with or without simultaneous irradiation with the Er:YAG and CO₂ lasers for 30 s repeated three times. The treatment groups consisted of 1: no treatment, 2: 0.5% H₂O₂ alone, 3: 0.5% NaOCl alone, 4: 0.12% CHX alone, 5: 2% NaF alone, 6: laser alone, 7: laser with 0.5% H₂O₂, 8: laser with 0.5% NaOCl, 9: laser with 0.12% CHX, and 10: laser with 2% NaF for both lasers. The microbial viability was determined through plating and viable colonies were counted, converted into CFU/mL, and transformed into log form. The statistical analysis was performed using a two-tailed paired t-test. (3) The use of CO₂ and Er:YAG lasers alone failed to show statistically significant antibacterial activity against any of the bacteria. The only effective monotreatment was CHX for S. mutans. The combined treatment of 0.5% NaOCl with Er:YAG produced the greatest reduction in overall viability. (4) The combination of the Er:YAG laser with 0.5% NaOCl resulted in the largest reduction in bacterial survival when compared to monotherapies with antimicrobial solutions or lasers.

A Narrative Review on Means to Promote Oxygenation and Angiogenesis in Oral Wound Healing

Oral mucosa serves as the primary barrier against pathogen invasions, mechanical stresses, and physical trauma. Although it is generally composed of keratinocytes and held in place by desmosomes, it shows variation in tissue elasticity and surface keratinization at different sites of the oral cavity. Wound healing undergoes four stages of tissue change sequences, namely haemostasis, inflammation, proliferation, and remodelling. The wound healing of oral hard tissue and soft tissue is largely dependent on the inflammatory response and vascular response, which are the targets of many research. Because of a less-robust inflammatory response, favourable saliva properties, a unique oral environment, and the presence of mesenchymal stem cells, oral wounds are reported to demonstrate rapid healing, less scar formation, and fewer inflammatory reactions. However, delayed oral wound healing is a major concern in certain populations with autoimmune disorders or underlying medical issues, or those subjected to surgically inflicted injuries. Various means of approach have been adopted to improve wound tissue proliferation without causing excessive scarring. This narrative review reappraises the current literature on the use of light, sound, mechanical, biological, and chemical means to enhance oxygen delivery to wounds. The current literature includes the use of hyperbaric oxygen and topical oxygen therapy, ultrasounds, lasers, platelet-rich plasma (PRP)/platelet-rich fibrin (PRF), and various chemical agents such as hyaluronic acid, astaxanthin, and Centella asiatica to promote angiogenesis in oral wound healing during the proliferation process. The arrival of a proprietary oral gel that is reported to improve oxygenation is highlighted.

Evaluation of Cortical Bone Thickness of Posterior Implant Sites Using CBCT in Iraqi Population

Background. Cortical bone thickness (CBT) is a critical factor for implant success and for determining the long-term dental implant treatment outcome. Objectives. The objective of this investigation was to examine posterior cortical bone thickness buccally and lingually in dentate and edentulous implant sites according to gender. Materials and Methods. CBT of 160 patients requiring a single posterior tooth implant was investigated by CBCT. The study included 80 males and 80 females. CBT was measured for implant edentulous sites at 3 levels including crestal bone (level 1), five mm from the crest (level 2), and ten mm from the crest (level 3). CBT was also measured for dentate sites at 3 levels including crestal bone (level 1), midroot bone (level 2), and apical portion (level 3). The differences of bone thickness between the levels of dentate sites were statistically analyzed using a Kruskal–Wallis one-way analysis of variance. Mann–Whitney test was used to determine the specific differences between group members. For the edentulous site, a one-way ANOVA was used. Results. CBT increased gradually from the crestal level to the apical level in all groups (buccal and lingual side, male and female). However, CBT at lingual side was statistically higher than that at buccal side in all groups. The mean value of CBT was significantly higher in males than females for both edentulous and dentate site. The dentate site shows a higher CBT in the apical level than the edentulous group in both male and female/buccal and lingual groups. Conclusion. CBT at the coronal levels is low and susceptible for resorption compared to the apical portion, especially for the female group. Moreover, CBT is thicker in males than females. It is essential to measure the CBT before making a treatment plan with dental implant prosthesis.

Evaluation of the effectiveness of a novel mouth rinse containing hyaluronic acid and hydrogen peroxide on gingivitis: A randomized pilot controlled trial

Objective

To evaluate and compare the effectiveness of a mouth rinse with hydrogen peroxide (H₂O₂) and hyaluronic acid (HA) versus a placebo mouth rinse on gingivitis.

Material and methods

This was a 21‐day, double blind, randomized, two‐arm parallel allocation placebo‐controlled trial of 50 study participants with a diagnosis of plaque‐induced gingivitis. Patients were randomly allocated to the test group or the placebo group and were assessed at three time points over the course of the study by the same operator, at baseline (T0), 7 days (T1), and 21 days follow‐up (T2). Primary outcomes of the trial were improvement in gingivitis and plaque accumulation.

Results

In both groups there was a decrease in gingival and plaque indices but the combination of the two actives (H₂O₂/HA) proved to be more effective against gingivitis (p = 0.001). Regarding plaque index, the differences between the test product and placebo were not statistically significant (p = 0.084). Besides, the new mouthwash was considered palatable, no adverse events were registered over the 21‐day period.

Conclusions

The H₂O₂ + HA product was more effective in reducing gingivitis when compared to a placebo while no differences were observed for plaque accumulation.

Pros and Cons of CAD/CAM Technology for Infection Prevention in Dental Settings during COVID-19 Outbreak

The purpose of this commentary is to update the evidence reported in our previous review on the advantages and limitations of computer-aided design/computer-aided manufacturing technology in the promotion of dental business, as well as to guarantee patient and occupational safety. The COVID-19 pandemic led to an unprecedented focus on infection prevention; however, waves of COVID-19 follow one another, asymptomatic cases are nearly impossible to identify by triage in a dental setting, and the effectiveness of long-lasting immune protection through vaccination remains largely unknown. Different national laws and international guidelines (mainly USA-CDC, ECDC) have often brought about dissimilar awareness and operational choices, and in general, there has been very limited attention to this technology. Here, we discuss its advantages and limitations in light of: (a) presence of SARS-CoV-2 in the oral cavity, saliva, and dental biofilm and activation of dormant microbial infections; (b) the prevention of SARS-CoV-2 transmission by aerosol and fomite contamination; (c) the detection of various oral manifestations of COVID-19; (d) specific information for the reprocessing of the scanner tip and the ward from the manufacturers.

Aloe vera mouthwashes can be a natural alternative to chemically formulated ones – A randomized-controlled trial

Objectives

To evaluate the antiplaque and antibacterial efficacy of commercially available mouthwashes containing aloe vera (AV), hydrogen peroxide (HP), and cetylpyridinium chloride (CPC) in a 4-day plaque regrowth study.

Methods

Plaque score and salivary samples were assessed (Day-0 and Day-4) in 96 participants in a randomised, double-blind prospective parallel-arm 4-day plaque regrowth study. Participants were divided into five groups who refrained from engaging in regular oral hygiene measures during the study period and used commercially available mouthwashes containing AV, HP, and CPC as test products with distilled water (DW) and chlorhexidine (CHX) mouthwash as negative and positive controls, respectively. Salivary bacterial count was expressed as colony-forming units (CFU) (culture method).

Results

There was a significant difference both in plaque score (p < 0.001) and in CFU (p < 0.001) among the study mouthwashes at Day-4. The plaque score and CFU of AV were significantly higher and lower than those of CHX and DW, respectively. The plaque score of HP was significantly higher than that of AV (p = 0.016) and CPC (p < 0.001). No significant difference was observed between AV and CPC (p = 0.70). Moreover, the CFU of HP was significantly higher than that of CPC (p = 0.04). There was no statistically significant difference between the CFU of mouthwashes containing AV and HP (p = 0.912) or AV and CPC (p = 0.280). No significant difference was seen in the inhibition of plaque and salivary bacterial count between AV, HP, and CPC.

Conclusion

The antiplaque and antibacterial efficacy of commercially available AV mouthwash was similar to that of CPC and significantly better than that of HP mouthwash and can be a natural alternative to chemically formulated mouthwashes.

Virucidal efficacy of chlorhexidine: a systematic review

This study aimed to systematically review the literature about the virucidal efficacy of CHX in comparison to other substances used in the oral cavity. Electronic searches were performed in four databases (PubMed, Scopus, Embase, and Web of Science). Only studies that presented the following characteristics were included: (1) verified virucidal efficacy of CHX against Herpes Simplex Type-1 (HSV-1), any Influenza, or any human coronavirus (HcoV); and (2) compared the virucidal efficacy of CHX with essential oils (Listerine^®), quaternary ammonium compounds, povidone-iodine, hydrogen peroxide, negative control substance, and absence of therapy. Two researchers independently selected the studies, extracted data and evaluated the risk of bias. A narrative data synthesis was used. Twenty-five studies were included, of which 21 were in vitro and four were randomized clinical trials (RCT). Studies assessed the virucidal efficacy of CHX against Herpes Simplex Type-1 (HSV-1) (10 studies), Influenza A (InfluA) (4 studies), human coronavirus (HCoV) (4 studies) and Severe Acute Respiratory Syndrome-Related Coronavirus (SARS-CoV-2) (11 studies). Most studies demonstrated that CHX has a positive virucidal efficacy against HSV-1 and InfluA strains. However, lower efficacy was shown to InfluA strain in comparison to povidone-iodine. Lower to none virucidal efficacy of CHX is expected for HCoV and SARS-CoV-2 strains for in vitro studies. Three RCT demonstrated that CHX was able to significantly reduce the viral load of SARS-CoV-2 for a short period. CHX may present an interesting virucidal efficacy against HSV-1 and InfluA viruses. CHX also presents transient efficacy against SARS-CoV-2 when used as a mouthwash.

Management of a Rare Case of Geminated and Fused Central Incisors in the Same Maxillary Dental Arch

A 27-year-old man presented with developmental disorders in the maxillary incisors and asymmetric smile. Differential diagnosis between geminated and fused maxillary central incisors was conducted using cone-beam computed tomography (CBCT). The complexities of root canal system was handled using suitable shaping instruments and ultrasonic activation tips. Root apexes were sealed with mineral trioxide aggregate plugs. The anterior maxillary gingiva was surgically recontoured, and CAD/CAM Zirconia crowns were placed after the gingival healing phase. The combination of the 3D radiological examination, the clinical screening, and the use of a diagnostic wax-up presented a successful approach to manage this rare clinical case.