Interpenetrating nanofibrillar membrane of self-assembled collagen and antimicrobial peptides for enhanced bone regeneration.

Bone regeneration remains a major clinical challenge, especially when infection necessitates prolonged antibiotic treatment. This study presents a membrane composed of self-assembled and interpenetrating GL13K, an antimicrobial peptide (AMP) derived from a salivary protein, in a collagen membrane for antimicrobial activity and enhanced bone regeneration. Commercially available collagen membranes were immersed in GL13K solution, and self-assembly was initiated by raising the solution pH to synthesize the multifunctional membrane called COL-GL. COL-GL was composed of interpenetrating large collagen fibers and short GL13K nanofibrils, which increased hydrophobicity, reduced biodegradation from collagenase, and stiffened the matrix compared to control collagen membranes. Incorporation of GL13K led to antimicrobial and anti-fouling activity against early oral surface colonizer Streptococcus gordonii while not affecting fibroblast cytocompatibility or pre-osteoblast osteogenic differentiation. GL13K in solution also reduced macrophage inflammatory cytokine expression and increased pro-healing cytokine expression. Bone formation in a rat calvarial model was accelerated at eight weeks with COL-GL compared to the gold-standard collagen membrane based on microcomputed tomography and histology. Interpenetration of GL13K within collagen sidesteps challenges with antimicrobial coatings on bone regeneration scaffolds while increasing bone regeneration. This strength makes COL-GL a promising approach to reduce post-surgical infections and aid bone regeneration in dental and orthopedic applications. STATEMENT OF SIGNIFICANCE: The COL-GL membrane, incorporating the antimicrobial peptide GL13K within a collagen membrane, signifies a noteworthy breakthrough in bone regeneration strategies for dental and orthopedic applications. By integrating self-assembled GL13K nanofibers into the membrane, this study successfully addresses the challenges associated with antimicrobial coatings, exhibiting improved antimicrobial and anti-fouling activity while preserving compatibility with fibroblasts and pre-osteoblasts. The accelerated bone formation observed in a rat calvarial model emphasizes the potential of this innovative approach to minimize post-surgical infections and enhance bone regeneration outcomes. As a promising alternative for future therapeutic interventions, this material tackles the clinical challenges of extended antibiotic treatments and antibiotic resistance in bone regeneration scenarios.

Effects of probiotics on the oral health of patients undergoing orthodontic treatment: a systematic review and meta-analysis.

BACKGROUND AND OBJECTIVE: The effect of probiotics on oral health maintenance in orthodontic patients remains controversial. The aim of the study is to systematically review and assess the effects of probiotics on the oral health and microbiome of patients undergoing orthodontic treatment. SEARCH METHODS AND SELECTION CRITERIA: Databases including PubMed, Web of Science, Cochrane Library, ClinicalTrials.gov, and ProQuest Dissertations & Theses Global databases were searched from their inception until June 2022. Randomised controlled trials that assessed the effects of probiotics on clinical and microbial outcomes in patients undergoing orthodontic treatment were included. DATA COLLECTION AND ANALYSIS: Data screening and collection were performed, and the risk of bias (RoB) was assessed using the Cochrane RoB 2 tool. The meta-analysis evaluated the effects of probiotics on Streptococcus mutans (S. mutans) and Lactobacillus counts. The quality of the evidence from the meta-analyses was assessed with Grading of Recommendations Assessment, Development and Evaluation (GRADE). RESULTS: A total of 405 records were identified, of which 15 studies were included in the qualitative synthesis and 4 in the meta-analysis. The patients in all the included studies were treated with fixed orthodontic appliances. Results regarding clinical outcomes were controversial; four out of five studies reported no significant changes in plaque in the probiotic group (P > .05), and two out of three studies reported no significant changes in the gingival index (P > .05). Regarding microbial outcomes, the meta-analysis results revealed that probiotics significantly increased the likelihood of reducing the abundance of S. mutans to below 105 CFU/ml (risk ratio: 2.05 [1.54, 2.72], P < .001) and reduced the likelihood of increasing the abundance of S. mutans to beyond 106 CFU/ml (risk ratio: 0.48 [0.28, 0.83], P = .009). However, the quality of evidence according to the GRADE was moderate. CONCLUSIONS AND IMPLICATIONS: There is insufficient evidence to determine the clinical benefits of probiotics as a supplement for the oral health of patients undergoing orthodontic treatment. However, probiotics may have benefits in reducing the salivary S. mutans counts in orthodontic patients. REGISTRATION: PROSPERO (CRD42022366650).

Maxillary anterior segmental distraction osteogenesis to correct maxillary hypoplasia and dental crowding in cleft palate patients: a preliminary study.

BACKGROUND: The aim of this study was to present comprehensive skeletal, dental and facial aesthetic outcomes and long-term stability of maxillary anterior segmental distraction osteogenesis (MASDO) for the treatment of maxillary hypoplasia in CLP. MATERIALS AND METHODS: Six patients with maxillary hypoplasia treated with MASDO by a miniscrew assisted intraoral tooth-borne distractor were included. Cephalometric radiographs were obtained before distraction (T1), after the consolidation period (T2) and after orthodontic treatment or before orthognathic surgery (T3). Thirty-one cephalometric variables (12 skeletal, 9 dental, and 10 soft tissue variables) were used to evaluate changes in the dentofacial structures and the soft tissue profile. Friedman and Wilcoxon tests were applied to identify significant differences in hard and soft tissue changes during the T1-T2, T2-T3, and T1-T3 periods. RESULTS: All patients successfully underwent MASDO without serious complications. From T1 to T2, forward movements of ANS and A (FH ⊥ N-A, VRL-ANS and VRL-A) were significant (p < 0.05). Significant increases in SNA and ANB were noted. Significant upward movement of points ANS (CFH-ANS) and A (CFH-A) was observed (p < 0.05). After distraction, a significant decrease in overjet and an increase in overbite were obtained (p < 0.05). Anterior tipping of the upper incisors (U1/ANS-PNS and U1/SN) was observed (p < 0.05). The soft tissue points of Pn, Sn, Ss, and ls showed significant anterior movement (p < 0.05). In addition, a significant increase in the nasolabial angle was measured (p < 0.05). All of the above data showed no statistically significant changes between T2 and T3 (p > 0.05). CONCLUSION: MASDO using a miniscrew assisted tooth-borne distractor presented significant maxillary advancement and favorable long-term stability in treating CLP patients with maxillary hypoplasia.

Effects of Two-Phase Treatment with Functional Appliances Followed by Extraction versus One-Phase Treatment with Extraction in Class II Growing Patients: A Case-Control Study.

Objectives: Fixed appliance treatment with premolar extraction is often required after functional appliance treatment to relieve crowding and improve facial aesthetics in the Asian population. This study compared the treatment efficacy of two approaches for treating Class II division 1 malocclusion: functional appliance followed by fixed appliance treatment with extraction (two-phase) and fixed appliance treatment with extraction (one-phase). Methods: Growing skeletal Class II patients with an overjet of ≥6 mm treated with two- or one-phase orthodontics were included. The two groups consisted of 29 patients (mean age = 12.55) and 30 patients (mean age = 12.72), respectively. Pre- and post-treatment cephalograms were analysed and skeletal, dental, and soft tissue characteristics were compared using independent t-tests. Treatment changes were compared within and between groups using paired and independent t-tests, respectively. Stepwise discriminant analysis was performed to identify the variables that best predicted pre-treatment group allocations. Results: At baseline, there were no significant between-group differences in age, gender, cervical vertebral maturation, or overjet. The two-phase group had greater Class II skeletal discrepancies (ANB angle and Wits appraisal). During treatment, the two-phase group showed greater improvements in intermaxillary relationship and facial convexity compared with the one-phase group (p < 0.01). Following treatment, the two-phase group had a greater L1/APog distance (p < 0.05). Facial convexity and Wits appraisal were identified as parameters significantly influencing the clinicians' decision to use a one- or two-phase approach. Conclusions: In patients requiring premolar extraction, two-phase (vs. one-phase) treatment produced greater improvements in the intermaxillary relationship and facial convexity.

Evaluation of the position and morphology of tongue and hyoid bone in skeletal Class II malocclusion based on cone beam computed tomography.

BACKGROUND: The aim of the study was to analyze the morphology and position of the tongue and hyoid bone in skeletal Class II patients with different vertical growth patterns by cone beam computed tomography in comparison to skeletal Class I patients. METHODS: Ninety subjects with malocclusion were divided into skeletal Class II and Class I groups by ANB angles. Based on different vertical growth patterns, subjects in each group were divided into 3 subgroups: high-angle group (MP-FH ≥ 32.0°), average-angle group (22.0° ≤ MP-FH < 32°) and low-angle group (MP-FH < 22°). The position and morphology of the tongue and hyoid bone were evaluated in the cone beam computed tomography images. The independent Student's t-test was used to compare the position and morphology of the tongue and hyoid bone between skeletal Class I and Class II groups. One-way analysis of variance (ANOVA) was used to compare the measurement indexes of different vertical facial patterns in each group. RESULTS: Patients in skeletal Class II group had lower tongue posture, and the tongue body was smaller than that of those in the Class I group (P < 0.05). The position of the hyoid bone was lower in the skeletal Class II group than in Class I group (P < 0.05). The tongue length and H-Me in the skeletal Class I group with a low angle were significantly larger than those with an average angle and high angle (P < 0.05). There was no significant difference in the position or morphology of the tongue and hyoid bone in the skeletal Class II group with different vertical facial patterns (P > 0.05). CONCLUSION: Patients with skeletal Class II malocclusion have lower tongue posture, a smaller tongue body, and greater occurrence of posterior inferior hyoid bone position than skeletal Class I patients. The length of the mandibular body in skeletal Class I patients with a horizontal growth type is longer. The position and morphology of the tongue and hyoid bone were not greatly affected by vertical facial development in skeletal Class II patients.

Comparative study of three composite materials in bonding attachments for clear aligners.

OBJECTIVE: The aim of this study was to assess the operation time, shear bond strength, placement accuracy and wear resistance of 3 composite materials (Filtek Z350XT, Filtek Z350XT Flowable and SonicFill) that were used to make attachments for clear aligners. SETTINGS AND SAMPLE POPULATION: Laboratory of Stomatology of Shanghai Ninth People's Hospital affiliated to Shanghai Jiao Tong University School of Medicine. A total of 129 human mandibular premolars were collected, 69 of which were assigned to 3 groups (A1, B1 and C1). The remaining 60 teeth were divided into 3 groups (A2, B2 and C2). METHODS: Z350XT composite resin was used in groups A1 and A2 to bond the attachments. Z350XT Flowable composite resin was used in groups B1 and B2. SonicFill composite resin was used in groups C1 and C2. The operation time, shear bond strength, the placement accuracy and wear volume loss of 3 composite materials were evaluated. RESULTS: The operation time of Z350XT Flowable and SonicFill was shorter than Z350XT (P < .05). The shear bond strength of SonicFill was higher than Z350XT and Z350XT Flowable (P < .05). The SEM showed that the bonding interface of Z350XT and SonicFill was compact. The 3D deviation and volumetric change in the 3D designed attachments and the attachments after actual bonding of Z350XT Flowable were greater than that of Z350XT and SonicFill (P < .05). The wear volume loss of SonicFill and Z350XT was less than that of Z350XT Flowable (P < .05). CONCLUSION: SonicFill seems to represent a suitable material for producing attachments, which optimized the property combination.