Many studies have found that the threshold of occlusal force tolerated by titanium-based implants is significantly lower than that of natural teeth due to differences in biomechanical mechanisms. Therefore, implants are considered to be susceptible to occlusal trauma. In clinical practice, many implants have shown satisfactory biocompatibility, but the balance between biomechanics and biofunction remains a huge clinical challenge. This paper comprehensively analyzes and summarizes various stress distribution optimization methods to explore strategies for improving the resistance of the implants to adverse stress. Improving stress resistance reduces occlusal trauma and shortens the gap between implants and natural teeth in occlusal function. The study found that: 1) specific implant-abutment connection design can change the force transfer efficiency and force conduction direction of the load at the BII; 2) reasonable implant surface structure and morphological character design can promote osseointegration, maintain alveolar bone height, and reduce the maximum effective stress at the BII; and 3) the elastic modulus of implants matched to surrounding bone tissue can reduce the stress shielding, resulting in a more uniform stress distribution at the BII. This study concluded that the core BII stress distribution optimization lies in increasing the stress distribution area and reducing the local stress peak value at the BII. This improves the biomechanical adaptability of the implants, increasing their long-term survival rate.

Periodontitis is a chronic inflammatory disease which increases in prevalence and severity in the older population. Aging is a leading risk factor for periodontitis, which exacerbates alveolar bone loss and results in tooth loss in the elderly. However, the mechanism by which aging affects periodontitis is not well understood. There is considerable evidence to suggest that targeting cellular senescence could slow down the fundamental aging process, and thus alleviate a series of age-related pathological conditions, likely including alveolar bone loss. Recently, it has been discovered that the senescent cells accumulate in the alveolar bone and promote a senescence-associated secretory phenotype (SASP). Senescent cells interacting with bacteria, together with secreted SASP components altering the local microenvironment and inducing paracrine effects in neighboring cells, exacerbate the chronic inflammation in periodontal tissue and lead to more alveolar bone loss. This review will probe into mechanisms underlying excessive alveolar bone loss in periodontitis with aging and discuss potential therapeutics for the treatment of alveolar bone loss targeting cellular senescence and the SASP. Inspecting the relationship between cellular senescence and periodontitis will lead to new avenues of research in this field and contribute to developing potential translatable clinical interventions to mitigate or even reverse the harmful effects of aging on oral health.

Maintenance of dental health has attracted attention of researchers at present. Various materials have been constructed and applied for curing different dental diseases, although limitation of biocompatibility and safety is still a big challenge. To overcome these limitations, nanomaterials with unique properties are incorporated into various dental treatment materials used in dental applications, including endodontic treatment, periodontal treatment, implant treatment, oral surgery, and restorative treatment, etc. Especially, reactive oxygen species-based nanomaterials equipped with nanoscale properties and reactive oxygen activities can be used as sterilization agents in dentistry, along with being used as good fillers in the dental field. This review concludes the common reactive oxygen species (ROS) nanomaterials and reviews the utilization of ROS in dentistry, highlighting the potential application and safety in clinical treatment. The future prospect will also be proposed to conduct the clinic dental cure.

The objective was to evaluate the efficacy of curcumin in improving mouth opening (MO), burning sensation (BS), and tongue protrusion (TP) symptoms in patients with oral submucous fibrosis (OSF). An electronic search up to November 2022 was conducted in the PubMed, Web of Science, Embase, EBSCO, ProQuest, and Cochrane Library databases to identify studies using curcumin in the treatment of OSF with comparison to control groups (drugs previously proven to be effective for OSF treatment) or placebo. Only randomized controlled trials (RCTs) were considered. RevMan 5.3 software was used for the meta-analysis. Thirteen RCTs met the eligibility criteria and were included in the analysis. The results showed no significant improvement in MO (in millimetres) for curcumin when compared to control at 1 month (P = 0.91), 2 months (P = 0.54), 3 months (P = 0.56), or 6 months (P = 0.17) of treatment. There was no significant difference in BS (assessed using a visual analogue scale) between curcumin and control after 1 month (P = 0.05), 2 months (P = 0.64), 3 months (P = 0.13), or 6 months (P = 0.56) of treatment. Compared with the control groups, treatment with curcumin for 1 month (P = 0.32), 2 months (P = 0.07), and 3 months (P = 0.14) did not significantly improve the TP (in millimetres) of patients. The administration of curcumin, whether topically applied or taken orally, did not confer statistically significant improvements in MO, BS, or TP in comparison to the control treatments, among patients with OSF. The results of this meta-analysis showed that compared to placebo, the application of curcumin for 6 months markedly alleviated BS (P < 0.001). Curcumin treatment in OSF reaches a clinically effective range, but more bioavailability-centred outcomes should be reported. Robust multicentre RCTs are warranted to elucidate the efficacy of curcumin in improving specific outcomes like MO, BS, and TP in patients with this condition. Defining the therapeutic role of this natural compound may provide an effective botanical alternative for managing OSF.

The porous structure can reduce the elastic modulus of a dental implant and better approximate the elastic characteristics of the material to the alveolar bone. Therefore, it has the potential to alleviate bone stress shielding around the implant. However, natural bone is heterogeneous, and, thus, introducing a porous structure may produce pathological bone stress. Herein, we designed a porous implant with axial gradient variation in porosity to alleviate stress shielding in the cancellous bone while controlling the peak stress value in the cortical bone margin region. The biomechanical distribution characteristics of axial gradient porous implants were studied using a finite element method. The analysis showed that a porous implant with an axial gradient variation in porosity ranging from 55% to 75% was the best structure. Under vertical and oblique loads, the proportion of the area with a stress value within the optimal stress interval at the bone–implant interface (BII) was 40.34% and 34.57%, respectively, which was 99% and 65% higher compared with that of the non-porous implant in the control group. Moreover, the maximum equivalent stress value in the implant with this pore parameter was 64.4 MPa, which was less than 1/7 of its theoretical yield strength. Axial gradient porous implants meet the strength requirements for bone implant applications. They can alleviate stress shielding in cancellous bone without increasing the stress concentration in the cortical bone margin, thereby optimizing the stress distribution pattern at the BII.