Horizontal ridge augmentation in the maxillary aesthetic region using the autogenous circular cortical-lamina anchoring technique: A case series study.

AIM: This case series aimed to evaluate the effectiveness of the autologous circular cortical lamina-anchoring (CCA) technique for horizontal bone augmentation in the maxillary aesthetic region. MATERIALS AND METHODS: A total of 25 patients with 28 implants underwent horizontal bone augmentation using CCA followed by implant placement and crown delivery. The primary outcome measures were alveolar ridge width (ARW) and buccal bone thickness (BBT), whereas the secondary outcome measures included marginal bone loss (MBL), mid-facial mucosal margin loss (MML), clinical assessment of peri-implant and aesthetic parameters, patient-reported outcome measures (PROMs), and implant survival rates. RESULTS: All 25 patients with 28 implants completed the treatment, no dropouts occurred. After CCA, the mean ARW at 1, 2, and 4 mm below the alveolar crest significantly increased from 2.38 ± 0.48, 2.85 ± 0.51, and 3.21 ± 0.53 mm to 6.80 ± 0.48, 6.99 ± 0.50, and 8.08 ± 0.52 mm, respectively. At the 3-year follow-up, the mean BBT0 , BBT2 , and BBT4 slightly decreased from 2.51 ± 0.26, 2.63 ± 0.31, and 2.75 ± 0.29 mm to 2.43 ± 0.27, 2.51 ± 0.30, and 2.64 ± 0.28 mm, respectively. Although the overall MBL was <0.15 mm, the results were statistically significant. The mean MML at the 3-year follow-up was 0.02 mm. All implant sites showed acceptable peri-implant and aesthetic outcomes. Incisions healed without complications, and no significant differences in PROMs observed at any time point. The 3-year follow-up showed a 100% implant survival rate. CONCLUSION: The autologous CCA technique is a useful method for increasing ARW and maintaining BBT in the maxillary aesthetic region.

Periodontal Regeneration of Teeth with Radicular Developmental Groove after Intentional Replantation: Two Case Reports.

Our case reports probe whether intentional replantation is a feasible and successful treatment for teeth with radicular developmental groove. Radicular developmental groove is an anatomical malformation that often leads to combined periodontal-endodontic lesion. Treatment of complex radicular groove presents a great challenge to the operator. Two cases of periodontal compromised teeth with this developmental anomaly were treated with intentional replantation and followed up for 2 years. The teeth were asymptomatic and functional. The periodontal probing depths decreased from original 10 mm to 2-3 mm. The receded gingival papillae associated with the teeth was regenerated two years after intentional replantation. With careful case selection and treatment planning, intentional replantation may be a predictable alternative treatment modality for the combined endodontic-periodontal lesion accompanied with radicular developmental groove.

Split-crest technique with inlay bone block grafts for narrow posterior mandibles: a retrospective clinical study with a 3-year follow-up.

The use of the split-crest technique (SCT) and bone block grafts provides benefits to horizontal bone augmentation. However, no information is currently available to evaluate the clinical effects of SCT combined with inlay bone block grafts on soft and hard tissues of the narrow posterior mandibles. In this study, 56 healthy patients underwent SCT to augment the alveolar ridge width. Implant placement was performed 3 months after SCT, and the implants were restored 3 months after placement. A planned follow-up was performed to analyze various clinical features, including X-ray radiographs, alveolar ridge width, and keratinized mucosal width, after SCT to evaluate the success of the procedure. The incisions healed well in all patients. The average initial alveolar ridge width was 2.78 ± 0.56 mm, which increased to 6.67 ± 0.60 mm after SCT. Three months later, this width declined slightly to 6.19 ± 0.48 mm. The average initial keratinized mucosal width was 2.83 ± 0.66 mm, which increased to 6.00 ± 0.71 mm 3 months later. Both at 3 months and 1 year after the procedure, vertical bone loss at the buccal sites was 1.32 ± 0.56 mm and 1.94 ± 0.54 mm, respectively. Survival rates of the implants were 100% after 3 years. SCT with inlay bone block grafts was successfully applied to narrow posterior mandibles with efficient augmentation of soft and hard tissue widths. The findings of this study aim to identify future beneficial applications of SCT.

Research progress on the crown-implant ratio and clinical complications / 口腔疾病防治

@#The crown-root ratio (C/R) theory of natural teeth has been widely recognized in the field of stomatology,and has important clinical significance in predicting and assessing the prognosis of natural teeth as well as for abutment selection during denture restoration. In the past few decades, scholars have advocated for the implantation of implants as long in length as possible to improve the success rate according to the theory of crown-root ratio of natural teeth. However, with the application of short implants, our philosophy of implantation has changed, and the relationship between the crown-implant (C/I) ratio and complications has become one of the current research hotspots. In this paper, the concept of the crown-implant ratio, the research progress of the C/I ratio, the implant survival rate and clinical complications of implant restoration were reviewed and summarized, and the following suggestions were put forward: although most studies have shown no significant correlation between the C/I ratio and implant survival or marginal bone loss, this relationship may increase the risk of mechanical complications. A C/I < 3 and a crown length < 15 mm are recommended in implant restoration; when ultra-short implants are applied, the implant system can increase the bone-to-implant contact area, and splint prostheses such as crown or bridge are recommended.

Effect of laser-etched pure titanium surface on early proliferation of MG63 cells / 口腔疾病防治

Objective @# To investigate the effect of a laser-etched pure titanium surface on proliferation of the human osteosarcoma cell line MG63 and to provide a basis for study of implant surface modification. @*Methods@#The pure titanium plate was cut into titanium pieces by a numerical control machine tool and divided into smooth surface and laser etching groups. The titanium surface of the laser etching group was etched with an Nd:YAG continuous wave laser using predetermined parameters, and the surfaces were observed by scanning electron microscopy (SEM). The surface micromorphology of each titanium sheet was evaluated. The relative element content of the titanium surface was measured by energy dispersive X-ray spectroscopy (EDS). The Ra value of each surface was determined using the Veeco roughness tester. MG63 cells were inoculated on 2 sets of titanium tablets. At 1, 3, and 6 h postinoculation, cell adhesion to the two groups of titanium sheets was observed under the microscope. At 24 h after inoculation, cellular F-actin was directly stained using immunofluorescence, and the morphology of the cytoskeleton was observed by laser confocal microscopy. Cell proliferation was examined at 1, 3, and 5 d using a MTS kit, and the data were analyzed with SAS 9.4.@* Results @#The surface of the smooth surface group was smooth and flat, the element composition was pure titanium, and the roughness Ra was 179.23 nm. The surface of the laser-etched group formed a regular and uniform pore structure. The composition was mainly Ti, O, C, etc, and the surface roughness Ra was 14.11 μm. A large number of cells were uniformly distributed on the two titanium sheets in the observations at 1, 3, and 6 h. At 24 h postinoculation, MG63 cells were completely stretched on the two sets of titanium sheets and had extended a large number of pseudopods and microfilaments to cross-link with peripheral cells; moreover, the cell division phase was observed. The cell proliferation of the two groups at 1, 3, and 5 d showed a significant increase with time, indicating that no cytotoxicity occurred on the surfaces of the two groups. However, the cell proliferation in the laser-etched group was superior to that in the mechanical smooth surface group.@*Conclusion@#The surface morphology of titanium can be controlled by laser etching, which is conductive to increase the microstructure of implants without cytotoxicity and promoting osteoblast proliferation in the early stage.

Clinical observation of alveolar ridge approach for odontogenic maxillary sinusitis and implant restoration / 口腔疾病防治

Objective @# To explore the clinical effect of the alveolar crest approach in the treatment of odontogenic maxillary sinusitis and the repair of edentulous implants in this area.@*Methods@#This was a retrospective case series of 20 patients with odontogenic sinusitis. The pathogenesis in each case was investigated. After elimination of the dental origin, each patient was treated with flushing, drainage and anti-inflammatories through the alveolar crest approach. Postoperative CBCT reexamination was performed to evaluate the therapeutic effect. Maxillary sinus elevation surgery with simultaneous or delayed implantation was performed after maxillary sinusitis healing was confirmed. The patients were followed postoperatively.@*Results @#Twenty patients with odontogenic sinusitis were treated by the alveolar crest approach, and 17 were cured, for a cure rate of 85%. Among them, 17 of the maxillary sinusitis patients were followed for 1 year, with good results.@*Conclusion @#The alveolar crest approach is feasible for the treatment of odontogenic maxillary sinusitis and can serve as a minimally invasive method for the repair of edentulism in this area and implantation.

Effect of Nd:YAG laser-nitriding-treated titanium nitride surface over Ti6Al4V substrate on the activity of MC3T3-E1 cells.

Ti6Al4V discs with a thickness of 2.5 mm and dimensions of 15 × 15 mm2 were fabricated. The titanium nitride (TiN) surface was formed via Nd:YAG laser-nitriding. A sandblast acid-etched (SA) surface was used as a control. Scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), and surface roughness tests were conducted to study the surface and cross-section morphologies as well as the properties of TiN and SA surfaces. MC3T3-E1 osteoblast-like cells were cultured on the TiN and SA surfaces to evaluate the effect of TiN surface on cellular behaviors, including attachment, proliferation and differentiation. Morphological testing results revealed that the cross-section of TiN exhibited dendritic crystallization without cracking. The proliferation and differentiation of MC3T3-E1 cells on the laser-nitriding TiN surface were significantly increased compared to those cultured on SA surface. These findings suggested that the TiN surface generated from Nd:YAG laser-nitriding were favorable for the proliferation and differentiation of MC3T3-E1 cells, which is significant for implant surface modification.

C-reactive protein, vitamin B12 and C677T polymorphism of N-5,10-methylenetetrahydrofolate reductase gene are related to insulin resistance and risk factors for metabolic syndrome in Chinese population.

PURPOSE: Metabolic syndrome (MS) and type 2 diabetes mellitus (T2DM) are complex diseases affected by both dietary intake and genetic background. Whether N-5, 10-methylenetetrahydrofolate reductase (MTHFR) C677T gene polymorphism, high-sensitivity C-reactive protein (hs-CRP) and dietary components folate and vitamin B12 are associated with MS in Asian has not been determined. METHODS: We hypothesized that MTHFR gene C677T, folate, vitamin B12 and hs-CRP are associated with MS and factors related to MS in northern Han Chinese. To test this hypothesis, MTHFR C677T gene polymorphism was determined by PCR-RFLP, serum insulin, folate and vitamin B12 levels by radioimmunoassay, and hs-CRP by immunoturbidimetry in newly diagnosed T2DM patients with MS (118) and without MS (40), and in 55 healthy subjects. RESULTS: Results indicated that MS-associated T2DM accounts for 75% of newly diagnosed T2DM in Han Chinese. Serum hs-CRP was higher and serum vitamin B12 was lower in subjects with TT genotype in comparison with those with CC or CT genotypes. Total T frequency was significantly higher in MS-associated T2DM patients (45.3%) compared to 26.3% in non-MS-associated T2DM patients. MTHFR C677T gene polymorphism and vitamin B12 levels were associated with MS-associated T2DM. CONCLUSION: MTHFR C677T gene polymorphism may contribute to insulin resistance in Han Chinese with MS by increasing hs-CRP and decreasing vitamin B12, and consequently play an important role in development of MS-associated T2DM.