OBJECTIVE: To assess the osteogenesis height in maxillary sinus segment one year after zygomatic implantation by imaging methods, and evaluate the influence of patient factors, maxillary sinus anatomical factors and surgical factors on postoperative osteogenesis height. METHODS: This study is a retrospective study, including patients who underwent zygomatic implantation and whose zygomatic implants passed through the maxillary sinus at the Department of Implantology, Peking University School and Hospital of Stomatology from July 2017 to January 2022. Preoperative and postoperative cone beam CT (CBCT)was taken to measure and calculate the average osteogenesis height (AOH) in maxillary sinus segment of the zygomatic implants, then the residual bone height, the width and morphology of the maxillary sinus floor in the buccal and palatal directions were measured. Besides, the integrity of Schneiderian membrane during implant surgery, and the general information of the patients and zygomatic implants were recorded. By comparing anatomical situations and surgical characteristics, the differences of AOH under different conditions were analyzed. Then AOH was divided into two groups (obvious osteogenesis group and non-obvious osteogenesis group) using the median as the threshold, and the influencing factors of osteogenesis were evaluated using mixed effect generalized linear model univariable and multivariable analysis. RESULTS: A total of 47 zygomatic implants were implanted in 24 patients. During the average follow-up period of 12.1 months, there was no implant failure, and the implant survival rate was 100%. Postoperative CBCT showed that 43 zygomatic implants had osteogenic images in the maxillary sinus segment, most of which originated from the floor of the maxillary sinus, and the median AOH was 3.1 mm [interquartile range (IQR): 4.0 mm]. In terms of maxillary sinus width, there were 31 cases (66.0%) of wide type and 16 cases (34.0%) of narrow type. In the aspect of buccal and palatal morphology, 17 cases were taper (36.2%), 20 cases were round (42.6%), and 10 cases were flat (21.3%). The median of residual bone height was 2.8 mm (IQR: 2.2 mm) before operation. Univa-riate analysis of mixed effect generalized linear model showed that postoperative obvious osteogenic rate was related to the residual bone height (OR=2.09, P=0.006). Multivariate analysis showed that the resi-dual bone height (OR=2.55, P=0.022) and the shape of a taper maxillary sinus (OR=11.44, P=0.040) had a significant impact on the postoperative obvious osteogenic rate. CONCLUSION The maxillary sinus floor showed osteogenic images 1 year after the zygomatic implantation surgery. Larger residual bone height and the shape of a taper maxillary sinus may be favorable factors for osteogenesis.
Humans ; Maxillary Sinus/surgery* ; Cone-Beam Computed Tomography ; Retrospective Studies ; Zygoma/diagnostic imaging* ; Male ; Female ; Osteogenesis/physiology* ; Middle Aged ; Adult ; Dental Implants ; Aged ; Dental Implantation, Endosseous/methods*

Nano-engineering-based tissue regeneration and local therapeutic delivery strategies show significant potential to reduce the health and economic burden associated with craniofacial defects, including traumas and tumours. Critical to the success of such nano-engineered non-resorbable craniofacial implants include load-bearing functioning and survival in complex local trauma conditions. Further, race to invade between multiple cells and pathogens is an important criterion that dictates the fate of the implant. In this pioneering review, we compare the therapeutic efficacy of nano-engineered titanium-based craniofacial implants towards maximised local therapy addressing bone formation/resorption, soft-tissue integration, bacterial infection and cancers/tumours. We present the various strategies to engineer titanium-based craniofacial implants in the macro-, micro- and nano-scales, using topographical, chemical, electrochemical, biological and therapeutic modifications. A particular focus is electrochemically anodised titanium implants with controlled nanotopographies that enable tailored and enhanced bioactivity and local therapeutic release. Next, we review the clinical translation challenges associated with such implants. This review will inform the readers of the latest developments and challenges related to therapeutic nano-engineered craniofacial implants.
Humans ; Titanium ; Dental Implants ; Wound Healing ; Surface Properties

OBJECTIVEThis research aimed to study the inhibitory effect of xylitol on the growth and acid production of Actinomyces viscosus (A. viscosus).

METHODSWe cultivated A. viscosus in anaerobic conditions with different concentrations (128, 64, 32, 16, 8, and 4 g x L(-1)) of xylitol brain heart infusion liquid medium and determined the minimum inhibitory concentration (MIC). Subsequently, we measured the pH value of the control group, as well as those of 1/2, 1/4, 1/8 MIC, and MIC concentration groups at 1.5, 3, 6, 12, 24, and 48 h. The Delta pH and OD550 at 2, 4, 6, 8, 10, and 12 h were calculated. We discovered that the minimum xylitol concentrations suppressed 50% and 90% A. viscosus biofilm formation (i.e., MBIC50 and MBIC90). SPSS 19.0 was used to analyze the collected data, and conclusions were drawn afterward.

RESULTSXylitol inhibited the growth ofA. viscosus at MIC of 64 g x L(-1). After 12 h, the differences of pH value among groups were all statistically significant (P < 0.05), and Delta pH increased when the MIC concentration decreased. Except for the 1/2 MIC and MIC groups, the differences of OD550 among groups had no statistical significance (P>0.05), and OD550 also increased when the MIC concentration decreased. These results imply that the ability ofA. viscosus to grow and produce acid in 1/2 MIC and MIC conditions will be reduced with the increase in xylitol concentration. The value of MIBC50 was 64 g x L(-1), whereas the value of MIBC90 was 128 g x L(-1). This finding indicates that the xylitol medium can restrict A. viscosus biofilm formation.

CONCLUSIONXylitolcan effectively inhibit the growth, adhesion, and acid production ofA. viscosus, protecting teeth from cariogenic bacteria and preventing caries to a certain extent.

Actinomyces viscosus ; Bacteria ; Dental Caries ; Humans ; In Vitro Techniques ; Xylitol

Objective This research aimed to study the inhibitory effect of xylitol on the growth and acid production of Actinomyces viscosus (A. viscosus). Methods We cultivated A. viscosus in anaerobic conditions with different concentrations (128, 64, 32, 16, 8, and 4 g·L-1) of xylitol brain heart infusion liquid medium and determined the minimum inhibitory concentration (MIC). Subsequently, we measured the pH value of the control group, as well as those of 1/2, 1/4, 1/8 MIC, and MIC concentration groups at 1.5, 3, 6, 12, 24, and 48 h. The ΔpH and OD550 at 2, 4, 6, 8, 10, and 12 h were calculated. We discovered that the minimum xylitol concentrations suppressed 50% and 90% A. viscosus biofilm formation (i.e., MBIC50 and MBIC90). SPSS 19.0 was used to analyze the collected data, and conclusions were drawn afterward. Results Xylitol inhibited the growth of A. viscosus at MIC of 64 g·L-1. After 12 h, the differences of pH value among groups were all statistically significant (P<0.05), and ΔpH increased when the MIC concentration decreased. Except for the1/2 MIC and MIC groups, the differences of OD550 among groups had no statistical significance (P>0.05), and OD550 also increased when the MIC concentration decreased. These results imply that the ability of A. viscosus to grow and produce acid in 1/2 MIC and MIC conditions will be reduced with the increase in xylitol concentration. The value of MIBC50 was 64 g·L-1, whereas the value of MIBC90 was 128 g·L-1. This finding indicates that the xylitol medium can restrict A. viscosus biofilm formation. Conclusion Xylitolcan effectively inhibit the growth, adhesion, and acid production of A. viscosus, protecting teeth from cariogenic bacteria and preventing caries to a certain extent.