Performance of Immediately Loaded Short Implants Using Low-Speed Drilling Protocol and Plasma Rich in Growth Factors: A Controlled Retrospective Observational Study.

Short dental implants are an alternative to surgical bone augmentation procedures and the placement of longer implants. The high predictability of short implants has encouraged clinicians to load them immediately. However, there are few studies assessing the influence of immediate vs delayed loading of short (< 8 mm) implants. The purpose of this retrospective study was to report the mid-term (5-year) outcomes (survival and marginal bone loss [MBL]) of immediate vs delayed loading of short implants. A total of 44 patients with 149 short implants fulfilled the inclusion criteria (95 and 54 implants with delayed and immediate loading, respectively). During the follow-up period, descriptive clinical variables, implant survival, MBL, and prosthetic complications were recorded and statistically analyzed. The mean follow-up time was 60 ± 40 months. The overall cumulative implant survival was 95.6%, and MBL was -0.1 ± 0.7 mm. No statistically significant differences were detected between the immediate and delayed loading groups in terms of implant survival (92.6% vs 97.5%) or MBL (-0.2 ± 0.8 mm vs -0.1 ± 0.7 mm), respectively. According to the results of this study, the immediate loading of short implants demonstrated predictability at the mid-term followup time. These results must be confirmed in future prospective studies. Int J Periodontics Restorative Dent 2023;43:233-239. doi: 10.11607/prd.5203.

Comparison of Plasma Lipoprotein Composition and Function in Cerebral Amyloid Angiopathy and Alzheimer's Disease.

Cerebral amyloid angiopathy (CAA) refers to beta-amyloid (Aß) deposition in brain vessels and is clinically the main cause of lobar intracerebral hemorrhage (ICH). Aß can also accumulate in brain parenchyma forming neuritic plaques in Alzheimer's disease (AD). Our study aimed to determine whether the peripheral lipid profile and lipoprotein composition are associated with cerebral beta-amyloidosis pathology and may reflect biological differences in AD and CAA. For this purpose, lipid and apolipoproteins levels were analyzed in plasma from 51 ICH-CAA patients (collected during the chronic phase of the disease), 60 AD patients, and 60 control subjects. Lipoproteins (VLDL, LDL, and HDL) were isolated and their composition and pro/antioxidant ability were determined. We observed that alterations in the lipid profile and lipoprotein composition were remarkable in the ICH-CAA group compared to control subjects, whereas the AD group presented no specific alterations compared with controls. ICH-CAA patients presented an atheroprotective profile, which consisted of lower total and LDL cholesterol levels. Plasma from chronic ICH-CAA patients also showed a redistribution of ApoC-III from HDL to VLDL and a higher ApoE/ApoC-III ratio in HDL. Whether these alterations reflect a protective response or have a causative effect on the pathology requires further investigation.

Platelet rich plasma in oral and maxillofacial surgery from the perspective of composition.

The application of platelet-rich plasma (PRP) in oral and maxillofacial surgery has been thoroughly studied in the last two decades. Currently, different types of PRP are applied in the clinical practice, being the presence or absence of leukocytes one of the classification criteria. However, there is poor evidence assessing the influence of the PRP composition in their efficacy. In this context, the aim of this narrative review is to compile the existing evidence covering the efficacy of PRP in oral and maxillofacial surgery, starting from a systematic literature search and to qualitatively describe the efficacy outcomes from the composition perspective. According to the results of this review, the application of PRP in oral and maxillofacial surgery is a potential strategy to improve soft- and hard-tissue regeneration, observing differences in the efficacy of PRP depending on its composition and the studied application. P-PRP (the absence of leukocytes) has been more consistent in achieving beneficial effects in alveolar ridge preservation, management of post-extraction complications, bone augmentation and temporomandibular joint disorders. For that, the composition and methodology used to prepare the PRP should be a critical point when evaluating the efficacy of PRP.

Long-Term Retrospective Study of 3.0-mm-Diameter Implants Supporting Fixed Multiple Prostheses: Immediate Versus Delayed Implant Loading.

PURPOSE: Narrow dental implants are commonly used to restore narrow alveolar ridges. Although the good performance of narrow dental implants supporting multiple prostheses has been repeatedly demonstrated, there are few studies analyzing their performance in a long-term follow-up together with the influence of the loading protocol. Thus, the objective was to assess the influence of implant loading protocol (immediate vs delayed) on the long-term outcomes of 3.0-mm-diameter dental implants supporting fixed multiple prostheses. MATERIALS AND METHODS: This retrospective cohort study included 202 3.0-mm-diameter dental implants supporting multiple prostheses placed between January 2006 and April 2009. Immediate loading was performed when the implants were inserted in bone types I, II, and III and achieved an insertion torque ≥ 25 Ncm; otherwise, delayed loading was performed. The survival of the dental implants was recorded together with clinical and demographic information of the participants. The prosthetic complications (ceramic chipping, screw loosening, screw fracture, decementation, prosthesis failure) were also recorded. The marginal bone loss since insertion and the marginal bone loss since loading were calculated. RESULTS: Delayed implant loading was performed in 131 implants and immediate loading in 71 implants. The follow-up time was 106 ± 40 months and 117 ± 38 months in the delayed and immediately loaded implants, respectively. The implant loading protocol (delayed vs immediate) showed no influence on the implant survival rate (96.2% vs 97.2%) and the marginal bone loss since insertion (1.2 ± 1.0 mm vs 1.2 ± 1.0 mm). CONCLUSION: The implant loading protocol (immediate vs delayed) did not influence the long-term outcomes (survival and marginal bone loss) of 3.0-mm-diameter dental implants supporting fixed multiple prostheses. These results are in favor of considering immediately loaded narrow dental implants as a viable treatment alternative for horizontally resorbed ridges. Nevertheless, future randomized clinical trials are needed to confirm these observations.

Survival and Marginal Bone Loss of Dental Implants Supporting Cad-Cam Angled Channel Restorations: A Split-Mouth Retrospective Study.

OBJECTIVE: The aim of this study was to determine whether the screw emergence angulation correction by computer-aided design (CAD)-computer-aided manufacturing (CAM) can influence implant survival and marginal bone stability. MATERIALS AND METHODS: This was a controlled split-mouth retrospective study of angled channel restorations. The dental implants supporting the prosthesis were divided into the following two groups: the first group (Group 1) included the implants that required screw channel angulation, while the second group (Group 2) included the implants that did not require this correction to screw the prosthesis to the implant. The main outcome variables were implant survival and marginal bone loss (MBL). RESULTS: A total of 68 dental implants placed in 22 patients were included in the final cohort. The mean follow-up time was 39.65 ± 15.20 months. None of the studied implants failed during the follow-up period and the mean MBL was - 0.29 ± 0.51 mm at the end of the follow-up. No statistical differences in the MBL were observed between the two groups of the study (-0.18 ± 0.51 and - 0.23 ± 0.58 mm, respectively). CONCLUSION: The angulation of the screw channel with CAD-CAM technology resulted in good clinical outcomes and did not affect MBL. Thus, the angulated screw channel might be considered an alternative to face undesired screw emergencies. Future prospective clinical studies should confirm these results.

Performance of the counter-torque technique in the explantation of nonmobile dental implants.

BACKGROUND: The application of the counter-torque technique has been proposed as a conservative and atraumatic alternative for the explantation of nonmobile dental implants. The objective of this report is to assess the performance of this technique in a large number of patients. RESULTS: Three hundred and fifty-five patients were treated for the explantation of 749 nonmobile dental implants. The explantations were performed by the application of counter-torque to break the bone-implant interface. Successful implant explantation was achieved in 98.4% of the implants. The frequency of complications was 1.3%, most commonly related to the appearance of fissure lines at the implant neck. CONCLUSIONS: The counter-torque technique has a high success rate but is not exempt from complications, although at a very low rate.

Characterization of ApoJ-reconstituted high-density lipoprotein (rHDL) nanodisc for the potential treatment of cerebral ß-amyloidosis.

Cerebral ß-amyloidosis is a major feature of Alzheimer's disease (AD), characterized by the accumulation of ß-amyloid protein (Aß) in the brain. Several studies have implicated lipid/lipoprotein metabolism in the regulation of ß-amyloidosis. In this regard, HDL (High Density Lipoprotein)-based therapies could ameliorate pathological features associated with AD. As apolipoprotein J (ApoJ) is a natural chaperone that interacts with Aß, avoiding its aggregation and toxicity, in this study we propose to prepare reconstituted rHDL-rApoJ nanoparticles by assembling phospholipids with recombinant human ApoJ (rApoJ). Hence, rHDL particles were prepared using the cholate dialysis method and characterized by N-PAGE, dynamic light scattering, circular dichroism and electron transmission microscopy. The preparation of rHDL particles showed two-sized populations with discoidal shape. Functionally, rHDL-rApoJ maintained the ability to prevent the Aß fibrillization and mediated a higher cholesterol efflux from cultured macrophages. Fluorescently-labelled rHDL-rApoJ nanoparticles were intravenously administrated in mice and their distribution over time was determined using an IVIS Xenogen® imager. It was confirmed that rHDL-rApoJ accumulated in the cranial region, especially in old transgenic mice presenting a high cerebral Aß load. In conclusion, we have standardized a reproducible protocol to produce rHDL-rApoJ nanoparticles, which may be potentially considered as a therapeutic option for ß-amyloid-related pathologies.

Intravenous treatment with human recombinant ApoA-I Milano reduces beta amyloid cerebral deposition in the APP23-transgenic mouse model of Alzheimer's disease.

Beyond the crucial role of apolipoprotein A-I (ApoA-I) on peripheral cholesterol metabolism, this apolipoprotein has also been implicated in beta amyloid (Aß)-related neuropathologies. ApoA-I-Milano (M) is a mutated variant, which showed increased vasoprotective properties compared to ApoA-I-wild type in models of atherosclerosis and cardiovascular damage. We speculated that ApoA-I-M may also protect Aß-affected vasculature and reverse some of the pathological features associated with Alzheimer's disease (AD). For this purpose, we produced and characterized human recombinant ApoA-I-wild type and ApoA-I-M proteins. Both of them were able to avoid the aggregation of Aß in vitro, even though recombinant ApoA-I-M was significantly more effective in protecting endothelial cells from Aß(1-42)-toxicity. Next, we determined the effect of chronic intravenous administration of rApoA-I-M in the APP23-transgenic mouse model of AD. We found reduced cerebral Aß levels in mice that received rApoA-I-M, which were accompanied by a lower expression of astrocyte and microglia neuroinflammatory markers. Our results suggest an applicability of this molecule as a therapeutic candidate for protecting the brain in AD.

Modulation of Amyloid-ß1-40 Transport by ApoA1 and ApoJ Across an in vitro Model of the Blood-Brain Barrier.

Amyloid-ß (Aß) accumulation in Alzheimer's disease (AD) and cerebral amyloid angiopathy (CAA) is likely caused by the impairment of its brain clearance that partly occurs through the blood-brain barrier (BBB). In this context, an in vitro BBB model is a valuable tool for studying the molecular mechanisms that regulate this process. This study assessed brain Aß elimination across the BBB and its modulation by the natural chaperones Apolipoprotein A1 (ApoA1) and Apolipoprotein J/Clusterin (ApoJ). The model was based on primary cerebral endothelial cells that were cultured on Matrigel-coated Transwells and treated with fluorescently labeled-Aß1-40 to track its efflux across the BBB, which corresponds to trafficking from the basolateral (brain) to apical (blood) compartments. We observed that the transport of basolateral Aß1-40 was enhanced when it was complexed to rApoJ, whereas the complex formed with rApoA1 did not influence Aß1-40 efflux. However, the presence of rApoA1 in the apical compartment was able to mobilize Aß1-40 from the basolateral side. We also observed that both rApoA1 and rApoJ moderately crossed the monolayer (from blood to brain) through a mechanism involving the LDL receptor-related protein family. In contrast to the increased rApoJ efflux when complexed to Aß1-40, rApoA1 trafficking was restricted when it was bound to the Aß peptide. In summary, the present study highlights the role of ApoJ and ApoA1 in the in vitro modulation of Aß elimination across the BBB.

Identification of Plasma Biomarkers of Human Intracerebral Hemorrhage Subtypes through Microarray Technology.

BACKGROUND: Intracerebral hemorrhage (ICH) is a devastating form of stroke and depending on the underlying cause, primary ICH is mainly caused by hypertension (HTN-ICH) or cerebral amyloid angiopathy (CAA-ICH). Currently, neuroimaging markers are required to identify the pattern for each etiology. The discovery of new biomarkers to improve the management of this pathology is therefore needed. METHODS: A microarray analysis was carried out to analyze gene expression differences in blood samples from patients (>1.5 months since the last ICH event) who suffered a CAA-ICH and HTN-ICH, and controls. The results were replicated by quantitative polymerase chain reaction and the plasma protein level of the best candidate was measured with enzyme-linked immunosorbent assay. RESULTS: The microarray analysis and the validation study revealed an increase in Golgin A8 Family, Member A (GOLGA8A) mRNA and protein levels in ICH cases compared to controls (P < .01), although no differences were found between specific ICH etiologies. GOLGA8A plasma levels were also associated with the presence of multiple hemorrhages (P < .05). CONCLUSIONS: The GOLGA8A level was increased in the blood of patients who suffered a primary ICH. We did not, however, find any candidate biomarker that distinguished CAA-ICH from HTN-ICH. The role of GOLGA8A in this fatal disorder has yet to be determined.