The quality of life after keratinized mucosa augmentation around dental implants using xenogenic collagen matrix with or without stent.

BACKGROUND: The substitution of missing teeth with implants is a dependable and anticipated therapeutic approach. Despite numerous studies affirming long-term success rates, there exists a spectrum of potential biological and aesthetic complications. OBJECTIVE: The primary objective of this study was to assess patient responses subsequent to surgical interventions, with a specific emphasis on the utilization of xenogenic collagen matrix (XCM), both with and without the application of a stent secured over healing abutments, in the context of keratinized gingival mucosa augmentation. The principal aim was to evaluate and draw comparisons between the clinical outcomes resulting from these two procedural approaches, with a particular focus on critical parameters encompassing post-operative complications, patient comfort, and the overall efficacy in achieving successful keratinized tissue augmentation. METHODS: Sixty patients were selected for this study. The patients were divided into three groups: A, B, and a control group, with each group comprising 20 participants. We used XCM in experimental group A, XCM covered with surgical stent in experimental group B, and free gingival graft (FGG) in the control group. After the surgical procedure, patients were required to complete a visual analogue scale (VAS) questionnaire for post-operative complications, and a quality of life (QOL) questionnaire on days 1, 3, and 7. RESULTS: Patients in the experimental groups A and B demonstrated markedly improved outcomes when compared with the control group. Assessments conducted on days 1, 3, and 7 demonstrated diminished levels of pain, bleeding, and swelling in both experimental groups, with experimental group B showing the least discomfort. The incorporation of XCM, either with or without stents, was associated with a reduction in analgesic consumption, underscoring its favorable influence on post-operative comfort, notwithstanding the exception of halitosis in experimental group B. CONCLUSION: Using XCM with or without a stent for keratinized tissue augmentation has better post-operative outcomes associated with reduced swelling, bleeding, and pain based on the QOL survey. This study provides data to support the clinical application of XCM and stents.

Mega-oss and Mega-TCP versus Bio-Oss granules fixed by alginate gel for bone regeneration.

OBJECTIVES/AIMS: Bone graft materials are widely used at present because inadequate bone volume is usually found in implant patients. To determine the biocompatibility of a new grafting material, in vitro research is routinely performed before animal experiments and clinical testing. However, during in vitro experiments, bone material particles might move during testing, which could affect the accuracy of the results. MATERIALS AND METHODS: To evaluate the biocompatibility of new bone substitutes, Mega-oss and Mega-TCP were compared with Bio-Oss using osteoblast cells and osteoclast cells fixed with alginate gel. Cell morphology, viability, bone resorption, alkaline phosphatase (ALP) activity, and staining were tested to compare the biocompatibility differences in the performance of Mega-oss, Mega-TCP, and Bio-Oss. RESULTS: Cells spread better on Mega-oss and Mega-TCP than the round shape on Bio-Oss. The 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) results showed that Mega-oss, Mega-TCP, and sodium alginate had good viability. Meanwhile, Mega-oss and Mega-TCP had the same osteoblast differentiation ability as Bio-Oss. The resorption rates of Mega-TCP and Mega-oss were higher than those of Bio-Oss (24.4%, 15.3%, and 3.3%, respectively). CONCLUSION: Mega-oss and Mega-TCP might be useful alternative bone graft materials compared with Bio-Oss. In addition, fixing the materials with sodium alginate gel could be a new method for in vitro bone material experiments.

[Short-term outcome of the acellular dermal matrix in dental implant surgical sites].

OBJECTIVE: To evaluate the clinical short-term results of the acellular dermal matrix for guided bone regeneration. METHODS: Sixty-four patients with bone defect in anterior maxillary area (average bone width: 3 mm) were included. Ridge-splitting technique with simultaneous placement of implants and artificial bone material implantation was performed in 21 patients (non-membrane group). Forty-three patients received the same procedure but with acellular dermal matrix covering the surgical sites (membrane group). The patients were followed up for three months and the new bone formation was checked in clinic and by X-ray. RESULTS: Three months after operation, the membrane group showed good osseointegration and high bone density over the implant cover screws. In the second operation, the membranes became thinner and the new bone fully covered the implant in the membrane group. The labial bone exhibited slight absorption and labial surface of 7 implants in 7 patients was exposed in non-membrane group. The width and the height of the ridge in the second operation were greater in membrane group than in non-membrane group (P < 0.05). CONCLUSIONS: The acellular dermal matrix can effectively resist the growth of soft tissue to allow bone regeneration around the implant.

[Clinical application of maxillary sinus lift with Summers osteotome].

OBJECTIVE: To introduce and evaluate the procedure and the effect of maxillary sinus lift with closed technique by Summers osteotome, bone grafting and simultaneous implant placement. METHODS: 66 cases with severely resorbed alveolar bone in maxillary posterior region received sinus lift with Summers osteotome, simultaneously bone grafting and implants placement. The final restoration was finished at 6 months postoperatively. RESULTS: The operation procedure were eventless in the 66 cases, the sinus floor were elevated by 2-5 mm, three-dimensional reconstruction of the CT scan pictures showed the smooth dome profile of the lifting sites and no signs of laceration on the membrane, and there were no maxillary antritis after operation. After 6 months, no significantly bone graft resorption and good osseointegration were noticed in X-ray imaging. The final restoration was finished at this time. 12-24 months after the restoration, all implants inserted were remain, the hard and soft tissue were healthy, prosthesis were stable and functioned. X-ray showed good osseointegration in the lifting sites, the vertical resorption around the implants were less than 1 mm. CONCLUSION: With properly use of Summers osteotome, scraps of the bone in the implant sockets can be pushed into the sinus, these autogenous bone scraps were in favor of the osseogenesis and the sinus floor can be easily elevated by the method with very infrequent complications. It enlarged indication of dental implants and avoided operation of harvesting autogenous bone in other site. The method is simple and valuable to clinical application.

[Development of sandwich ELISA for equine interferon-gamma detection].

AIM: To develop a quantitative ELISA by measuring interferon (IFN-gamma) of equine lymphocytes. METHODS: Sandwich ELISA for equine IFN-gamma was developed using mAb A5 as a capture antibody and biotinylated mAb SB10 as a detection antibody. RESULTS: The detection limit of the sandwich ELISA for equine IFN-gamma was 1 microg/L and did not show cross-reactivity with recombinant equine IL-18. Equine IFN-gamma was detected by ELISA in culture medium of the peripheral blood mononuclear cells (PBMCs) stimulated with ConA or PMA/Ionomycin. CONCLUSION: This method can be used to help understand the role of this cytokine in various equine diseases and develop specific cell-mediated immunity assay.

[Clinical study of immediate implant-support and mandibular overdentures retained by conical crowns].

PURPOSE: To evaluate the clinical effectiveness and feasibility of immediate implant-supported mandibular overdentures retained by conical crowns. METHODS: In this study, 10 patients with edentulous mandible were included. They were restored by traditional complete denture before operation. All patients received 4 dental implants in the inteforaminal region and had the implants loaded with all overdenture prostheses retained by conical crowns at that day. All patients were followed up for 2, 4, 8, 12, 24, 48 weeks. The stability of implants, the state of peri-implant soft-tissue, marginal bone resorption, the state of osseointegration of implants, and patient satisfaction were evaluated. RESULTS: A total of 40 implants were loaded immediately. All implants had osseointegration. No infections of peri-implant soft-tissue occurred, no implants exhibited peri-implant radio lucencies, marginal bone had no resorption. The patients were satisfied with the outcomes. CONCLUSION: The results of this clinical trial suggest that immediate loading of the implants by conical crowns to support overdenture prostheses for edentulous mandible is predictable, if primary implant stable is.

[Clinical study of autotransplanting of impacted anterior tooth and premolar].

OBJECTIVE: To evaluate the effect of autotransplantation of impacted anterior tooth and premolar. METHODS: Nineteen teeth of 19 patients were made autotransplantation. Fifteen impacted anterior teeth were transplanted to their normal positions. Four premolars were transplanted into missing anterior spaces. Four weeks after surgical procedure, root canal therapy was underwent. Clinical and radiographic examintation of 19 transplanted teeth were carried out after 18-months to 5-years. RESULTS: Nineteen teeth were stable with no sign of inflammatory resorption or periapical lesion. CONCLUSION: Autotransplantation may be a better treatment method to impacted tooth and missing anterior when they can't be treated by orthodontic method.