Can Plasma Rich in Growth Factors Expedite Healing of Postextraction Tooth Sockets in Patients Undergoing Urgent Liver Transplantation?

PURPOSE: Infections foster morbidity and mortality after liver transplantation (LT). Pre-LT eradication of oral infectious foci is not always possible for patients needing an urgent LT because postextraction sockets must be healed before the patient is operated, and this requires at least 3 weeks. To accelerate healing, we tested the effect of plasma-rich growth factor (PRGF), a highly concentrated form of autogenous platelets on healing. MATERIALS AND METHODS: Prospective case-control split-mouth study for more than 100 candidates for LT needing routine extractions of 2 homologous teeth: a socket was to be treated with PRGF, whereas its match (control [CTRL]) was to undergo natural healing. The outcome of interest was the socket size derived from the measurements on the transversal diameters and deepest level of penetration on the PRGF and CTRL sides after extraction and on day 7, 14, and 21 postextraction. The primary predictor was treatment status (PRGF vs CTRL); secondary predictors, the tooth extracted and patient's features. The statistical analysis used nonparametric tests and best subset regression. RESULTS: All measurements evidenced a significantly (P < .0001) more advanced closure on the PRGF side than the CTRL side. One week after extraction, PRGF sockets were reduced to 12% (molars) and 6% (nonmolars) of the original wound versus 32 and 20% for CTRL, respectively. The percentage of PRGF sockets with size less than or equal to 5% was 7% for molars and 44% for nonmolars versus 0 and 12% for CTRL (P < .0001), respectively. The percentages with size less than or equal to 10% were 37% for molars and 81% for nonmolars on the PRGF side versus 2 and 26% on the CTRL side, respectively. These percentages showed a significant decrease for smoking patients. CONCLUSIONS: The outcome of our trial showed that PRGF significantly accelerates closure of postextraction sockets. Its use, at least in patients who occupy top positions in the LT waiting list, is recommended.

In-vivo usefulness of optical coherence tomography in atrophic-erosive oral lichen planus: Comparison between histopathological and ultrastructural findings.

Oral lichen planus (OLP) is a common premalignant chronic inflammatory disorder. Optical Coherence Tomography (OCT) provides a real-time, non-invasive, and in-situ optical signature using light of varying wavelengths to examine tissue. Aim of the present study was to assess the possible role of OCT as diagnostic tool for atrophic-erosive OLP by examining OCT scans of healthy buccal mucosa, and comparing their ultrastructural features with those of a buccal mucosa affected by atrophic-erosive OLP, using their histopathological counterparts as the gold standard. Through grayscale (enface scan) and an application in which the vascularization of the tissue is visible (dynamic scan), it was possible to distinguish the healthy from the lichenoid pattern from 20 controls (12 M; 8 F; mean age: 41.32 years) and 20 patients with histologically confirmed atrophic-erosive OLP (7 M; 13 F; mean age: 64.27 years). In detail, mean width of stratified squamous epithelium (EP) and lamina propria (LP) were evaluated. Among controls, EP and LP showed a mean width of 300 (±50) and of 600 (±50) µm respectively; among cases, disruption of membrane basement prevented from any measurement. Furthermore, a differential pattern of EP and LP emerged between the two groups: a light-grayish, hypo-reflective, homogeneous area of EP recurring in controls turned into a hyper-reflective, non-homogeneous area among cases. Dynamic scan showed a differential profile of LP vascularization, varying from a hypo-reflective red area with small blood vessels in the control group, to a hypo/hyper-reflective area, completely overrun by a denser, wider blood flow amid OLP cases. Although histopathological examination remains the gold standard for OLP diagnosis, OCT could be a potentially helpful tool for the clinician and the pathologist, since it allows analysis of the vascularization of the sample without adversely affecting histological processing.

Effects of argon plasma treatment on the osteoconductivity of bone grafting materials.

BACKGROUND: The osteoconductive properties of bone grafting materials represent one area of research for the management of bony defects found in the fields of periodontology and oral surgery. From a physico-chemical aspect, the wettability of the graft has been demonstrated to be one of the most important factors for new bone formation. It is also well-known that argon plasma treatment (PAT) and ultraviolet irradiation (UV) may increase the surface wettability and, consequently, improve the regenerative potential of the bone grafts. Therefore, the aim of the present in vitro study was to evaluate the effect of PAT and UV treatment on the osteoconductive potential of various bone grafts. MATERIALS AND METHODS: The following four frequently used bone grafts were selected for this study: synthetic hydroxyapatite (Mg-HA), biphasic calcium phosphate (BCP), cancellous and cortical xenogenic bone matrices (CaBM, CoBM). Sixty-six serially numbered disks 10 mm in diameter were used for each graft material and randomly assigned to the following three groups: test 1 (PAT), test 2 (UV), and control (no treatment). Six samples underwent topographic analysis using SEM pre- and post-treatments to evaluate changes in surface topography/characteristics. Additionally, cell adhesion and cell proliferation were evaluated at 2 and 72 h respectively following incubation in a three-dimensional culture system utilizing a bioreactor. Furthermore, the effects of PAT and UV on immune cells were assessed by measuring the viability of human macrophages at 24 h. RESULTS: The topographic analysis showed different initial morphologies of the commercial biomaterials (e.g., Mg-HA and BCP showed flat morphology; BM samples were extremely porous with high roughness). The surface analysis following experimental treatments did not demonstrate topographical difference when compared with controls. Investigation of cells demonstrated that PAT treatment significantly increased cell adhesion of all 4 evaluated bone substitutes, whereas UV failed to show any statistically significant differences. The viability test revealed no differences in terms of macrophage adhesion on any of the tested surfaces. CONCLUSION: Within their limitations, the present results suggest that treatment of various bone grafting materials with PAT appears to enhance the osteoconductivity of bone substitutes in the early stage by improving osteoblast adhesion without concomitantly affecting macrophage viability. CLINICAL RELEVANCE: Treatment of bone grafts with PAT appears to result in faster osseointegration of the bone grafting materials and may thus favorably influence bone regeneration.

Piezoelectric implant surgery and immediate loading in the aesthetic zone.

BACKGROUND: Replacement of missing teeth in the anterior aesthetic zone has challenged clinicians with fixed, removable or implant prosthodontics. Problems have been encountered could void aesthetic and functional results. The aim of this study was to present a clinical case report in which clinician challenged a very strong aesthetic case with an innovative surgical and prosthetic approach. METHODS: A patient who presented to the authors with a maxillary central incisor that had a hopeless prognosis secondary to acute localized severe periodontitis. The patient was treated by extracting the tooth and replacing it immediately with a platform switched implant using piezoelectric surgery. The implant was then restored with an immediate, non-occlusal loading provisional restoration. RESULTS: The implant became osseointegrated and was ultimately restored with a definitive abutment and crown restoration. CONCLUSIONS: Innovative approaches could represent a valid alternative to restore patients functionally and aesthetically.

Is It Safe to Remove Teeth in Liver Transplant Patients Without Antibiotics? A Retrospective Study of 346 Patients.

PURPOSE: Eradication of oral infectious foci is essential for liver transplant candidates. The main issue is whether antibiotic prophylaxis is necessary for all dental extractions despite the possible fostering of resistant bacteria. To overcome the scarcity of evidence-based data, our study analyzed the background and outcomes of a large number of routine extractions performed in our institution without antibiotic prophylaxis in patients with different liver pathologies. MATERIALS AND METHODS: In this retrospective cohort study, the outcome of interest was the occurrence of local infections and minor complications during the 7-day follow-up period after extraction; the predictors were the demographic and clinical variables of the patients (age, gender, liver pathology, Model for End-Stage Liver Disease score, international normalized ratio) and the extraction variables (single vs multiple extractions, isolated vs contiguous teeth, single-rooted vs multirooted teeth). The statistical analysis used univariate nonparametric tests and binary multivariate logistic regressions. RESULTS: The 346 liver transplant candidates (mean age, 53 ± 8 years; 24% women) underwent 662 routine extraction sessions involving 1,329 teeth. The 7-day dental follow-up detected no signs of postoperative wound infection (rate = 0% [95% confidence interval (CI), 0 to 0.9%]). Accordingly, the 2-week post-extraction clinical monitoring excluded symptoms of systemic infection attributable to the dental procedure. Minor complications (mild bleeding, slow healing, inflamed socket) occurred in 50 patients (rate = 14% [95% CI, 11 to 18%]) in the 3 days after extraction. Significant risk factors for minor complications were refractory ascites (P < .0001; OR = 8 [95% CI, 3 to 20]), extraction of multirooted contiguous teeth (P < 0.0001; OR = 5 [95% CI, 2.5 to 9]), and a Model for End-Stage Liver Disease score greater than 18 (P = 0.01; OR = 2.4 [95% CI, 1.2 to 5]). CONCLUSIONS: Our study showed that routine extractions without antibiotic prophylaxis can be performed safely in liver transplant candidates, even in the presence of 1 or more non-controllable risk factors. Using atraumatic techniques, we achieved satisfactory healing of the gingiva and socket in all patients in a week, without any signs of local infection. The few minor complications were readily managed and resolved within 3 days after extraction.

A 4-Year Retrospective Radiographic Study of Marginal Bone Loss of 156 Titanium Implants Placed with Ultrasonic Site Preparation.

This retrospective study evaluated implant survival rate (SR) and marginal bone loss around dental implants placed with ultrasonic implant site preparation. A total of 156 implants were placed in 28 totally and partially edentulous patients. Bone loss was measured on intraoral paralleling digital radiographs taken at the impression phase and after 4 years of loading. As 3 implants (1.92%) failed at the second surgery stage, the SR was 98.08% after 4 years. The mean marginal bone loss was 0.52 ± 0.33 mm (0.51 ± 0.35 mm mesially and 0.53 ± 0.35 mm distally), with comparable values for implants inserted into the maxilla (0.52 ± 0.32 mm) and the mandible (0.52 ± 0.35 mm).

Direct Oral Anticoagulants and Medical Comorbidities in Patients Needing Dental Extractions: Management of the Risk of Bleeding.

PURPOSE: The purpose of this study was to measure the frequency of bleeding during and after tooth extraction in patients exposed to direct oral anticoagulants (DOACs) and identify risk factors for prolonged or excessive bleeding. MATERIALS AND METHODS: This retrospective cohort study involved 100 patients who underwent tooth extractions according to the European Heart Rhythm Association protocol: continuation of DOAC therapy for extractions of up to 3 teeth in the same session performed at the (presumed) time of DOAC trough concentration. We respected an interval of at least 4 hours between extraction and last DOAC intake. The outcome of interest was incidence of mild, moderate, and severe bleeding during the intervention and in the 7-day follow-up period. Data analysis considered the presence of comorbidities as the primary predictor for bleeding; additional predictors were age, gender, type of comorbidity, indication for DOAC therapy, DOAC agent, and extraction of contiguous teeth. RESULTS: Of the patients, 64 had comorbidities (diabetes in 50%). The distributions of demographic, clinical, and dental variables were similar for patients with and without comorbidities. We observed 4 bleeding episodes (1 moderate episode 1 hour after the extraction and 3 mild episodes the day after the extraction) in the comorbidity group and none in the non-comorbidity group (4 of 64 vs 0 of 36, P = .29; overall bleeding rate, 4 of 100). The factor significantly triggering bleeding in patients with comorbidity was extractions of couples and triplets of multirooted teeth (P = .004). CONCLUSIONS: Tooth extractions in patients with comorbidities taking DOACs may be safely managed as long as they are performed at least 4 hours after the last DOAC intake and do not involve 2 or 3 contiguous premolars and molars.

Early Response of Fibroblasts and Epithelial Cells to Pink-Shaded Anodized Dental Implant Abutments: An In Vitro Study.

PURPOSE: This research aimed to assess whether pink-shaded anodized surfaces could enhance the adhesion of soft tissue cells compared with untreated machined titanium surfaces. MATERIALS AND METHODS: Two types of Ti-Al-V titanium samples were prepared: machined titanium (Ti) and anodized titanium (AnoTi). The microstructure was studied by means of a scanning electron microscope. X-ray photoelectron spectroscopy (XPS) was carried out as well. The wetting properties were investigated by the sessile drop technique with water and diiodomethane. To investigate the biologic response in vitro, the epithelial cell line HaCaT and the fibroblastic cell line NHDF were used. Cell adhesion, morphology, and proliferation were evaluated. RESULTS: The microstructure of the tested surfaces was irregularly smooth for both types of samples with no relevant morphologic differences. The XPS and HR-XPS performed on the AnoTi samples confirmed the presence of Ti, O, and C, along with Ti oxides. Following the optical contact angle measurements, the anodization process induced a slight transition toward the hydrophobic regime. Consequently, the surface free energy values differed significantly between the anodized and the machined samples. Anodized Ti significantly increased the adhesion and proliferation of both epithelial cells and fibroblasts when compared with the pristine Ti controls. CONCLUSION: Compared with the clinical standard, anodized surfaces could enhance the adhesion of the two major cell types within the peri-implant soft tissues, which makes pink anodization a promising option for implant dentistry.

Apical periodontitis: preliminary assessment of microbiota by 16S rRNA high throughput amplicon target sequencing.

BACKGROUND: Apical periodontitis includes periapical granulomas and radicular cysts, which are histologically distinguished by the absence and the presence of an epithelial lining, respectively. The main cause of apical periodontitis is the bacterial colonization of the root canal space. This research aimed at assessing whether and how periapical granulomas and radicular cysts differ in terms of microbiota using high throughput amplicon target sequencing (HTS) techniques. METHODS: This study included 5 cases of Periapical Granulomas (PGs) and 5 cases of Radicular Cysts (RCs) selected on the base of histology out of 37 patients from January 2015 to February 2016. Complete medical history, panoramic radiograms (OPTs) and histologic records of each patient were assessed. Only lesions greater than 1 cm in diameter and developed in proximity to teeth with bad prognosis were included. The microbiota present in periapical granulomas and radicular cysts thus retrieved was finely characterized by pyrosequencing of the 16S rRNA genes. RESULTS: The core of OTUs shared between periapical granulomas and radicular cysts was dominated by the presence of facultative anaerobes taxa such as: Lactococcus lactis, Propionibacterium acnes, Staphylococcus warneri, Acinetobacter johnsonii and Gemellales. L. lactis, the main OTUs of the entire datasets, was associated with periapical granuloma samples. Consistently with literature, the anaerobic taxa detected were most abundant in radicular cyst samples. Indeed, a higher abundance of presumptive predicted metabolic pathways related to Lipopolysaccharide biosynthesis was found in radicular cyst samples. CONCLUSIONS: The present pilot study confirmed the different microbial characterization of the two main apical periodontitis types and shade light on the possible role of L. lactis in periapical granulomas.

Salivary extracellular vesicle-associated miRNAs as potential biomarkers in oral squamous cell carcinoma.

BACKGROUND: Several studies in the past have investigated the expression of micro RNAs (miRNAs) in saliva as potential biomarkers. Since miRNAs associated with extracellular vesicles (EVs) are known to be protected from enzymatic degradation, we evaluated whether salivary EVs from patients with oral squamous cell carcinoma (OSCC) were enriched with specific subsets of miRNAs. METHODS: OSCC patients and controls were matched with regards to age, gender and risk factors. Total RNA was extracted from salivary EVs and the differential expression of miRNAs was evaluated by qRT-PCR array and qRT-PCR. The discrimination power of up-regulated miRNAs as biomarkers in OSCC patients versus controls was evaluated by the Receiver Operating Characteristic (ROC) curves. RESULTS: A preliminary qRT-PCR array was performed on samples from 5 OSCC patients and 5 healthy controls whereby a subset of miRNAs were identified that were differentially expressed. On the basis of these results, a cohort of additional 16 patients and 6 controls were analyzed to further confirm the miRNAs that were up-regulated or selectively expressed in the previous pilot study. The following miRNAs: miR-302b-3p and miR-517b-3p were expressed only in EVs from OSCC patients and miR-512-3p and miR-412-3p were up-regulated in salivary EVs from OSCC patients compared to controls with the ROC curve showing a good discrimination power for OSCC diagnosis. The Kyoto Encyclopedia of Gene and Genomes (KEGG) pathway analysis suggested the possible involvement of the miRNAs identified in pathways activated in OSCC. CONCLUSIONS: In this work, we suggest that salivary EVs isolated by a simple charge-based precipitation technique can be exploited as a non-invasive source of miRNAs for OSCC diagnosis. Moreover, we have identified a subset of miRNAs selectively enriched in EVs of OSCC patients that could be potential biomarkers.

Heme accumulation in endothelial cells impairs angiogenesis by triggering paraptosis.

Heme is required for cell respiration and survival. Nevertheless, its intracellular levels need to be finely regulated to avoid heme excess, which may catalyze the production of reactive oxygen species (ROS) and promote cell death. Here, we show that alteration of heme homeostasis in endothelial cells due to the loss of the heme exporter FLVCR1a, results in impaired angiogenesis. In vitro, FLVCR1a silencing in endothelial cells causes defective tubulogenesis and poor viability due to intracellular heme accumulation. Consistently, endothelial-specific Flvcr1a knockout mice show aberrant angiogenesis responsible for hemorrhages and embryonic lethality. Importantly, we demonstrate that impaired heme export leads to endothelial cell death by paraptosis and provide evidence that endoplasmic reticulum (ER) stress precedes heme-induced paraptosis. These findings highlight a crucial role for the cytosolic heme pool in the control of endothelial cell survival and in the regulation of the angiogenic process. Interfering with endothelial heme export represents a valuable model for a deeper understanding of the molecular mechanisms underlying heme-triggered paraptosis and, in the future, might provide a novel tool for the modulation of angiogenesis in pathophysiologic conditions.

Oral Surgical Treatment of Patients With Chronic Liver Disease: Assessments of Bleeding and Its Relationship With Thrombocytopenia and Blood Coagulation Parameters.

PURPOSE: Cirrhotic patients awaiting liver transplantation require eradication of infectious oral foci to prevent septic episodes after transplantation; however, cirrhosis can hinder hemostasis and can result in severe bleeding. The present study assessed the bleeding risk factors connected with the clinical history of these patients and the characteristics of the extractions. MATERIALS AND METHODS: We retrospectively analyzed 1183 extractions in 318 patients, including 47 with severe end-stage liver disease who were outside of our intention-to-treat bracket (ie, platelet count [PLT] >40 × 103/µL and international normalized ratio [INR] <2.5). Follow-up examinations included inspection of the oral cavity on the first, third, and seventh days, with reparatory surgery in the case of severe bleeding. Continuous variables were compared using the Mann-Whitney U and Kruskal-Wallis tests, and categorical variables were compared using Fisher's exact test. Binary logistic regression analysis was also performed. RESULTS: Within the intention-to-treat bracket, 1 of the 271 patients (0.4%) required surgical repair. The bleeding rate for an INR of 2.5 or more was significantly greater than that for a PLT of 40 × 103/µL or less (4 of 10 [40%] versus 2 of 34 [6%]; P = .02]. All 3 patients with both an INR of 2.5 or more and a PLT of 40 × 103/µL or less exhibited severe bleeding. No significant association between the occurrence of bleeding with either liver disease etiology or the number of molars extracted was found. No patient required hospitalization. CONCLUSIONS: Patients with a PLT greater than 40 × 103/µL and an INR of less than 2.5 can be considered relatively low-risk patients. However, an INR of 2.5 or more and, to a minor degree, a PLT of 40 × 103/µL or less represent significant risk factors.

Transglutaminase 2 May Be Associated with Peri-implant Gingival Overgrowth: Preliminary Assessments.

UNLABELLED: Tissue transglutaminase 2 (TG2) is ubiquitously expressed in normal tissues and plays an important role in the pathophysiology of wound healing. An increase in periodontal tissues has been previously reported in cyclosporine-induced gingival overgrowth. PURPOSE: The aim of this study was to explore associations between TG2 expression and the vascularization and maturation processes of peri-implant soft tissues over time. MATERIALS AND METHODS: Edentulous patients proposed for mandibular implant-retained overdentures were included in the study. Biopsies of the peri-implant mucosa were performed at the first surgical stage and at 4, 8, and 12 months after prosthetic load. A follow-up program was directed to record plaque indexes, bleeding on probing data, and pocket probing depth around implants. An evaluation of the vessels' density was carried out by digital virtual microscopy and using an immunohistochemistry approach (antibodies anti-CD31, anti-TG2). A robust multivariable regression model was implemented. RESULTS: According to model results, blood vessel count and probing (as a marker of gingival overgrowth in absence of plaque) significantly decrease over time and are associated with TG2, particularly for values above the median. CONCLUSION: The association of an increased TG2 expression in the extracellular matrix might have a significant impact in the development of gingival overgrowth around a loaded implant.

Simplified edentulous treatment technique for edentulous hemimaxillectomy patients: case history report.

Technical difficulties in the construction of hard palate obturators following oncologic surgery are due to the recording limitations of the entire defect area, plus prosthesis base instability during recording of maxillomandibular relationships. This article describes a time-saving technique that ensures stable and precise recording bases. A light-polymerizing acrylic resin layer is used for making the first impression of the defect, while simultaneously obtaining an acrylic resin impression tray and base for recording maxillomandibular relationships. Adhesive paper copies are used for the arrangement of the anterior teeth.

A split-mouth randomized clinical trial to evaluate the performance of piezosurgery compared with traditional technique in lower wisdom tooth removal.

PURPOSE: The surgical removal of mandibular third molars is frequently accompanied by significant postsurgical sequelae, and different protocols have been described to decrease such adverse events. The aim of this study was to investigate the performance of piezosurgery compared with traditional rotating instruments during mandibular third molar removal. PATIENTS AND METHODS: A single-center, randomized, split-mouth study was performed using a consecutive series of unrelated healthy patients attending the Oral Surgery Unit of the University of Turin for surgical removal of bilateral mandibular third molar teeth. Each patient was treated, at the same appointment, using bur removal on 1 side of the mandible and a piezoelectric device on the contralateral side. The primary outcomes reported were postoperative pain, objective orofacial swelling, and surgical duration; secondary outcomes were gender, age, and possible adverse events. Analysis of variance or paired t test was used as appropriate to test any significant differences at baseline according to each treatment subgroup, and categorical variables were analyzed by χ(2) test. RESULTS: The study sample consisted of 100 otherwise healthy patients. The mean pain evaluation reported by patients who underwent surgery with piezosurgery was significantly lower than that reported after bur (conventional) removal, reaching statistical difference after 4 days (P = .043). The clinical value of orofacial swelling at day 7, normalized to baseline, was lower in the piezosurgery group (P < .005). The average surgical duration was significantly shorter in the bur group than in the piezosurgery group (P < .05). Three patients having bur removal developed short-term complications (2 dry sockets and 1 temporary paraesthesia), which totally resolved by 4 weeks. CONCLUSIONS: To date, this prospective investigation is the largest reported split-mouth study on piezosurgery for lower third molar tooth removal. This study also compared surgeons with different degrees of experience. It is evident that using a piezoelectric device can enhance the patient experience and decrease postoperative pain and swelling.

Presence of osteoinductive factors in bovine colostrum.

New approaches in the treatment of skeletal defects may benefit from the use of soluble biological factors. We previously standardized a derivative of bovine colostrum (SBCD), deprived of casein and fat and rich in cytokines. In the present study, we tested its possible use as an adjuvant in bone healing. SBCD contained factors involved in stromal cell stimulation and differentiation and induced cytokine production from stimulated mesenchymal stem cells (MSCs). In vitro, SBCD promoted proliferation, migration and, in association with osteogenic factors, osteogenic differentiation of osteoblastic and MSCs. In in vivo experiments of subcutaneous Matrigel injection in mice, SBCD plus hydroxyapatite, but not hydroxyapatite nor SBCD alone, induced recruitment of macrophages and stromal cells. After 60 days, plugs containing SBCD and hydroxyapatite were densely calcified and diffusely positive for osteocalcin, supporting the occurrence of an early osteogenic process. These results indicate that SBCD is a rich source of factors with osteoinductive properties.

Ultrasonic implant site preparation using piezosurgery: a multicenter case series study analyzing 3,579 implants with a 1- to 3-year follow-up.

This multicenter case series introduces an innovative ultrasonic implant site preparation (UISP) technique as an alternative to the use of traditional rotary instruments. A total of 3,579 implants were inserted in 1,885 subjects, and the sites were prepared using a specific ultrasonic device with a 1- to 3-year follow-up. No surgical complications related to the UISP protocol were reported for any of the implant sites. Seventy-eight implants (59 maxillary, 19 mandibular) failed within 5 months of insertion, for an overall osseointegration percentage of 97.82% (97.14% maxilla, 98.75% mandible). Three maxillary implants failed after 3 years of loading, with an overall implant survival rate of 97.74% (96.99% maxilla, 98.75% mandible).

Immediate postextractive dental implant placement with immediate loading on four implants for mandibular-full-arch rehabilitation: a retrospective analysis.

BACKGROUND: To date, only few studies have reported on the clinical outcomes of immediate postextraction implant placement and immediate loading. PURPOSE: The purpose of this retrospective study was to report the results of immediately loading four implants placed in fresh extraction sockets in the mandible after a follow-up of 24 months. MATERIALS AND METHODS: Between January 2001 and January 2009, 50 patients (28 women and 22 men, average age 54 years), had 347 teeth extracted and a total of 200 dental implants placed in the mandible. The patients received a provisional fixed bridge the same day and a permanent one 3 months later. Clinical checkups were performed after 1, 2, 3, 6, 12, and 24 months. Marginal bone measurements were made in intraoral radiographs taken 1 day after surgery and after 1 year. A questionnaire was used to evaluate self-perceived factors related to comfort, aesthetics, and function. RESULTS: All bridges were stable and no implant failures were recorded during the follow-up, giving a survival rate of 100%, at 2 years. The marginal bone loss amounted to 1.33 ± 0.36 mm after 1 year and 1.48 ± 0.39 mm after 2 years. Ten patients showed prosthetic complications with the provisional bridge, but all the definitive prostheses remained stable throughout the study period without any complications. The patients reported satisfaction with the treatment. CONCLUSIONS: The present retrospective study showed that immediate loading of four implants immediately placed in extraction sockets is a valid treatment modality for the totally edentulous mandible.

Oral mucosa produces cytokines and factors influencing osteoclast activity and endothelial cell proliferation, in patients with osteonecrosis of jaw after treatment with zoledronic acid.

OBJECTIVES: The intravenous injection of bisphosphonates, currently used as treatment for osteoporosis, bone Paget's disease, multiple myeloma, or bone metastases, can cause jaw bone necrosis especially in consequence of trauma. The present research aimed to clarify the mechanisms underlying bone necrosis, exploring involvement of the oral mucosa "in vivo." PATIENTS AND METHODS: Specimens of oral mucosa were removed from bisphosphonate-treated patients with or without jaw bone necrosis. In mucosa specimens, expression was evaluated of: cytokines involved in the inflammatory process, factors involved in osteoclast activity, i.e., receptor activator of nuclear factor kappa-B ligand (RANKL) and osteoprotegerin, a factor involved in cell proliferation, namely hydroxymethylglutaryl coenzyme A reductase, and a factor involved in angiogenesis, namely vascular endothelial growth factor (VEGF). RESULTS: Interleukin (IL)-6 and the RANK/osteoprotegerin ratio were significantly elevated in mucosa from patients with versus without jaw necrosis, whereas hydroxymethylglutaryl coenzyme A reductase and VEGF were significantly decreased. CONCLUSIONS: Our results suggest that mucosa, stimulated by bisphosphonate released from the bone, can contribute to the development of jaw necrosis, reducing VEGF, and producing IL-6 in consequence of hydroxymethylglutaryl coenzyme A reductase reduction. In turn, IL-6 stimulates osteoclast activity, as shown by the increased RANKL/osteoprotegerin ratio. CLINICAL RELEVANCE: The results of this study suggest the importance of evaluating during bisphosphonate treatment the production of IL-6, RANKL, osteoprotegerin, and VEGF, in order to monitor the jaw osteonecrosis onset. To avoid repeated mucosa excisions, the determination of these factors could be carried out in crevicular fluid.

Immediate postextraction implant placement with immediate loading for maxillary full-arch rehabilitation: A two-year retrospective analysis.

BACKGROUND: There are few studies in the literature regarding immediate postextraction implant placement with immediate loading in the maxilla. These studies have only small cohorts. Therefore, the authors conducted a retrospective study to help fill this knowledge gap. METHODS: Between January 2001 and January 2009, 65 participants (32 women, 33 men) with an average age of 60.5 years (age range, 43-83 years) received 334 dental implants, which were placed in postextraction sockets and loaded immediately. The follow-up period for this retrospective study was two years. RESULTS: All prostheses were stable, and only seven implants failed during the follow-up, for a 100 percent prosthetic survival rate and a 97.9 percent implant survival rate at two years. The mean (standard deviation) implant bone level measured 0.50 (0.27) millimeter at insertion, 1.90 (0.51) mm at one year and 2.06 (0.49) mm at two years. CONCLUSIONS: The results of this retrospective study showed that the survival rate of immediately loaded postextraction implants is comparable with that reported for traditional delayed implants in the maxilla. CLINICAL IMPLICATIONS: Immediate loading of four to six implants placed in extraction sockets may be a valid way to treat the edentulous maxilla.