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Sialolithiasis or “salivary lithiasis” is a pathological condition that involves the formation of calcified concrements within the gland parenchyma and its ductal system of the main salivary glands of the head and neck area. Various theories of lithogenesis have been reported, but the etiology of sialoliths still remains unclear. The aim of this case report was to evaluate the biochemical composition and the surface morphology of a sialolith using energy dispersion X-ray spectroscopy (EDX) and scanning electron microscopy (SEM). SEM images of the sialolith detected a concentric laminar architecture of the sialolith’s core surrounded by radial structures that are arranged from the center to the periphery of the sialolith. EDX analysis detected a high percentage of carbon in the central area of the sialolith, indicating the abundance of organic materials. Structures corresponding to a foreign body or bacteria were not detected in any area. Thus, the sialolith presented a mixed genesis, and the increased presence of organic substances over inorganic ones suggests its phlogistic nature.

The efficacy of SARS-CoV-2 mRNA-based vaccines in preventing COVID-19 disease has been extensively demonstrated; however, it is of uttermost importance to acquire knowledge on the persistence of immune-protection both in terms of levels of neutralizing antibodies and specialized memory cells. This can provide important scientific basis for decisions on the need of additional vaccine doses and on when these should be administered thus resulting in an improvement in vaccination schedules. Here, we briefly report the changes in antibody levels and cellular immunity following BNT162b2 administration. We show an important fall in anti S1-Spike antibodies in BNT162b2 vaccinated subjects overtime, paralleled by a contextual consolidation of specific spike (S) T-cells, mainly of the CD8+ compartment. Contrariwise, CD4+ S-specific response shows a considerable interindividual variability. These data suggest that the well-known antibody drop in vaccinated subjects is replaced by memory cell consolidation that can protect from severe adverse effects of SARS-CoV-2 infection.

Obstructive sleep apnea syndrome (OSAS) is a sleep breathing disorder that often remains undiagnosed and untreated. OSAS prevalence is increasing exponentially. Starting on the dentist’s role as an epidemiological and diagnostic “sentinel”, the purpose of this study was to assess the prevalence of OSAS. The clinical diaries of 4659 patients were reviewed through a single-center retrospective analytic study. Descriptive statistical analysis was performed. Only 0.26% of patients reported to suffer from sleep apnea and were then diagnosed with OSAS. It was found that, out of 4487 patients, 678 suffered from hypertension (14.80%), 188 from gastro-esophageal-reflux-disease (GERD = 4.10%) and 484 from gastritis (10.78%). These results could be related to a difficult diagnosis of OSAS and to the absence of a dedicated section on sleep disorders in medical records. Therefore, the introduction of a question dedicated to sleep disorders, the administration of questionnaires (such as the STOP-BANG questionnaire) for early diagnosis, a multidisciplinary approach and pneumological examination could support the dentist in identifying patients at risk of OSAS.

The purposes of this study were to evaluate the efficacy of water–airborne-particle abrasion (WAPA) as pre-etching procedure for tooth surfaces to increase bond strength, and to compare the survival rate of WAPA vs. non-WAPA glass–ceramic restorations with a 15-year follow-up. The occlusal surfaces of 20 human molars were sectioned and flattened. The prepared surfaces areas were subdivided into two parts: one received WAPA treatment (prophy jet handpiece with 50 µm aluminium oxide particles) followed by acid etching (37% phosphoric acid for 20 s/3-step etch-and-rinse), the other one was only acid-etched. In total, 108 specimens were obtained from the teeth, of which 80 were used to measure the micro-tensile bond strength (μTBS) in the WAPA (n = 40) and control (n = 40) groups, while the remaining specimens (n = 28) were investigated via SEM to evaluate the micromorphology and roughness (Ra) before and after the different treatment steps. The survival rate (SR) was performed on 465 glass–ceramic restorations (131 patients) comparing WAPA treatment (n = 183) versus non-WAPA treatment (n = 282). The bond strength was 63.9 ± 7.7 MPa for the WAPA group and 51.7 ± 10.8 MPa for the control group (p &lt, 0.001). The Ra was 98 ± 24 µm for the enamel control group, 150 ± 35 µm for the enamel WAPA group, 102 ± 27 µm for the dentin control group and 160 ± 25 µm for the dentin WAPA group. The Ra increase from the WAPA procedure for enamel and dentin was statistically significant (p &lt, 0.05). Under SEM, resin tags were present in both groups although in the WAPA they appeared to be extended in a 3D arrangement. The SR of the WAPA group (11.4 years) was 94%, while the SR of the non-WAPA group (12.3 years) was 87.6% (p &lt, 0.05). The WAPA treatment using aluminium oxide particles followed by a 3-step etch-and-rinse adhesive system significantly improved bioadhesion with an increased bond strength of 23.6% and provided superior long-term clinical performance of glass–ceramic restorations.

The novel Coronavirus Disease 2019 (COVID-19) pandemic has renewed attention to aerosol-generating procedures (AGPs). Dental-care workers are at high risk of contamination by SARS-CoV-2. The aim of this study was to evaluate the efficacy of standard saliva ejectors and natural ventilation in reducing particulate matter (PM) concentration during different routine dental procedures in the pandemic period. The DustTrak monitor was used to measure PM1, PM2.5, PM10, and breathable (&lt, 4 microns) total dust during 14 procedures performed with and without the presence of natural ventilation in a dental unit. Moreover, measurements were performed near the practitioners or near the standard saliva ejectors during the different procedures. In the latter condition, reduced levels of PM10 were recorded (82.40 ± 9.65 μg/m3 vs. 50.52 ± 0.23 μg/m3). Moreover, higher levels of PM (53.95 ± 2.29 μg/m3 vs. 27.85 ± 0.14 μg/m3) were produced when the dental unit’s windows were open. At the same time, the total level of PM were higher during scaling than during other procedures (data suggest not to adopt natural ventilation—both window and door opened—during dental procedures). It was also demonstrated that the use of standard saliva ejectors can considerably reduce the total released amount of PM10.

Background and Objectives: The objective of this study was to evaluate the association between periodontal disease and obstructive sleep apnea syndrome (OSAS). Materials and Methods: Electronic search using PubMed, Scopus, LILACS, and Cochrane library was carried out for randomized controlled trials, cohort, case-control, longitudinal and epidemiological studies on humans published from January 2009 until September 2020. The participants had to be male and female adults who were diagnosed with OSAS either by overnight polysomnography (carried out at a sleep laboratory or at home) or by a home sleep testing monitor (Apnea Risk Evaluation System). Methodological quality assessment was carried out using the Newcastle-Ottawa Quality Assessment Scale (NOS) for case-control studies while an adapted form of NOS was used for cross-sectional studies. Results: Ten studies fulfilled the inclusion criteria of our review, 5 were case-control studies, and 5 cross-sectional. Sample size ranged from 50 to 29,284 subjects, for a total of 43,122 subjects, 56% of them were male, their age ranged from 18 to 85 years old. The heterogeneity among the studies regarding the classification of periodontal disease, and the different methods for OSAS severity assessment, complicated the comparison among the studies. Conclusions: There is low evidence of a possible association between OSAS and periodontitis. The pathophysiological mechanism, cause-effect, or dose-response relationship are still unclear. Further studies are needed and should use a precise classification of OSAS subjects, while the new classification of periodontitis from the World Workshop of Chicago 2017 should be used for the periodontal assessment.

The COVID-19 pandemic literally stopped most human movement and activities as it initially spread, which included dental practices and dental education. This defined the need for significative changes in teaching and learning with the use of “e-learning” methods, also for traineeships. This study was designed to determine the undergraduate student perception of these new methods as part of their education. This involved 353 students attending the Dental School of the G. D’Annunzio University of Chieti–Pescara, from the first to the sixth years. A questionnaire in Italian and was set-up using “Google Forms” and sent by email to the students. The questionnaire was divided into three parts: the first part included questions for general information, including age, sex and year of course, the second part had multiple choice questions related to their evaluation of the e-learning teaching, using a scale of opinion in the replies to each question (e.g., “scarce”, “fair”, “satisfying”, “very good” and “excellent”), and the third part included two open questions to indicate the strengths and limitations of these new teaching and learning approaches. The categorical variables in the first and second parts of the questionnaire were evaluated using Chi squared tests, setting significance at p &lt, 0.05, while the comments were evaluated qualitatively. The student feedback showed significant appreciation (p &lt, 0.05) of the new methods and the efforts that the lecturers put in to provide lectures of as high a quality as possible. However, a lack of practical training was significantly perceived as an important problem in the structure of their new curriculum (p &lt, 0.05). COVID-19 has been an epic tragedy that has hit the human population not only in terms of health and healthcare, but also quality of life. This includes the quality of dental education within universities. However, the pandemic can be seen to also represent motivation to invest in the necessary technological innovation to deliver the best possible education to our future dentists.

The literature highlights differences in the dental conditions of people with disabilities compared with the general population. The aim of this study was to provide an overview of the dental health of people with disabilities in order to understand if their needs are met and to identify their most critical issues as per dentists. A paper and a Google Form platform were used in conducting a survey in Central Italy (the Abruzzo region), by performing an analysis on different points of view as reported by people with disabilities and dentists. The results showed that only 69.2% of dentists treat persons with disabilities. Of these, 73.5% treat less than 10 patients with physical disabilities per year. However, 54% of dentists do not treat people with cognitive impairment and a poor ability to collaborate during treatment. More than 80% of respondent dentists report that people with disabilities do not have good oral hygiene. On the other hand, 49.1% of people with disabilities (or their caregivers in cases where the patient was unable to answer) report that they rarely or never go to the dental office. Moreover, when they do go, it is mainly for emergencies. Despite this, respondents are well aware of their dental problems. However, they have difficulties in communicating their dental problems to their dentist. The 50% of dentists who treat people with cognitive impairment do not include them in follow-up, while only 20% of these patients reported being regularly recalled. This illustrates the importance of the implementation of follow-up. In addition, training courses could help clinicians to reduce this gap and create barrier-free dental offices.

BACKGROUND Growing evidence shows the efficacy of platelet concentrates in periodontal therapy. This study aimed to demonstrate that an inorganic bovine bone graft (IBB) in combination with a leukocyte and platelet rich fibrin (L-PRF) is non-inferior to a combination with a collagen membrane (CM) when managing unfavorable infrabony defects (IBDs). METHODS All patients exhibited at least one unfavorable IBD; they were randomly assigned to two groups, 31 treated with L-PRF+IBB and 31 with CM+IBB. A clinical and radiographic examination was performed at baseline and 12 months later. Clinical attachment level (CAL), gingival recession (GR), probing depth (PD), and radiographic defect bone level (DBL) post-therapy changes were compared between the two treatments. A non-inferiority margin = 1 mm was set to determine the efficacy of the test treatment (-1 mm for GR); a second non-inferiority margin = 0.5 mm (-0.5 mm for GR) was chosen for clinical relevance. RESULTS Twelve months after surgery a significant improvement of clinical and radiographic parameters was observed at both experimental sites. The 90% confidence intervals of the CM+IBB-L-PRF+IBB mean difference for CAL gain (-0.810 mm [-1.300 to -0.319]) and DBL gain (-0.648 mm [-1.244 to -0.052]) were below the 0.5 mm non-inferiority margin; GR increase (1.284 mm [0.764 to 1.804]) remained above the -0.5 mm, while PD reduction (0.499 mm [0.145 to 0.853]) crossed its 0.5-mm margin. CONCLUSIONS The L-PRF+IBB treatment of unfavorable IBDs offers non-inferior efficacy for CAL gain, showing less GR and more DBL gain too, while for PD reduction it is inferior to the CM+IBB treatment.

Background. Inflammatory responses have been associated with delayed oral mucosal wound healing and the pathogenesis of the periodontal disease. The invasion of microbes into the tissues and the establishment of a chronic infection may be due to impaired healing. The protracted inflammatory phase may delay wound healing and probably support tissue fibrosis and reduce tissue regeneration. Vanillin is a well-known natural compound with potential anti-inflammatory capacity. Hence, we hypothesized that Vanillin could accelerate wound healing reducing inflammation and especially cytokine production making the oral tissue repair process easier. Methods. Our hypothesis was tested using primary human gingival fibroblast (HGF) cell pretreated with Vanillin and primed with IL-1β, as inductor of proinflammatory environment. After 24 hours of treatments, the gene expression and production of IL-6, TNF-α, IL-8, COX-2, iNOS, and nitric oxide (NO) generation and the wound healing rate were determined. Results. In IL-1β-primed cells, preincubation with Vanillin reduced IL-6, IL-8, COX-2, and iNOS expression and NO release, compared to IL-1β-primed cells. Moreover, Vanillin determines the increased gene expression of nAChRα7, leading us to hypothesize a role of Vanillin in the activation of the cholinergic anti-inflammatory pathway. Furthermore, in presence of mechanical injury, the Vanillin preincubation, wound closure may be reducing the expression and release of IL-6 and TNF-α and upregulation of COX-2 and IL-8. Conclusion. Together, the results of this study highlight the anti-inflammatory and tissue repair ability of Vanillin in IL-1β-primed HGF. Therefore, Vanillin shows a potential therapeutic interest as an inflammatory modulator molecule with novel application in periodontal regeneration and oral health.

The correlation between SARS-CoV-2 and oral manifestations is still controversial. The aim of this observational study was to determine the oral manifestation of the hospitalized patients for COVID-19. A total of 20 patients met the inclusion criteria and gave their signed informed consent. A questionnaire of 32 questions regarding the oral and systemic health condition was administrated to these patients during the convalescence. A descriptive statistic was performed. Data were analysed through the use of &chi, 2 test, to assess the statistical significance. A statistically significant increase of about 30% of reporting xerostomia during hospitalization was observed (p = 0.02). Meanwhile, a decrease of oral hygiene was observed during the hospitalization, even if a non-statistically significant difference was shown between the two study time points (before and after hospitalization). During the hospitalization period, 25% of patients reported impaired taste, 15% burning sensation, and 20% difficulty in swallowing. An interesting result was that among the systemic conditions, hypertension was observed in 39% of patients and mostly in female patients (62.5%). Further studies are necessary to better understand the symptoms of this new virus in order to faster detect its presence in humans. Probably, a multidisciplinary team following the COVID-19 patients could be of key importance in treating this disease.

Xerostomia is a symptom frequently present in patients with type 1 (T1DM) and type 2 diabetes mellitus (T2DM). In the present trial, the activity of an artificial saliva (aldiamed&reg, spray) in comparison to a placebo spray were used to evaluate the xerostomia and the saliva antioxidant capacity (SAT). Sixty patients of both genders with T1DM or T2DM were randomized into two groups of 30 subjects each. The experiment was a double-blind study approved by the Ethics Committee of the &ldquo, G. d&rsquo, Annunzio University&rdquo, of Chieti and Pescara. Moreover, measurements of the stimulated saliva flow rate and the ultrasonography of the submandibular and parotid glands were performed at both the study time points. The results demonstrated statistically significant differences between the treatments in terms of the xerostomia average score. Specifically, the values were at baseline and after 30 days 2.9 &plusmn, 1.31 and 3.0 &plusmn, 1.44 and 1.4 &plusmn, 1.48 and 2.4 &plusmn, 0.99 for aldiamed&reg, spray and the placebo, respectively. Meanwhile, no statistically significant differences were shown between the two groups for the other variables, such as the salivary flow rate, the antioxidant capacity of the saliva, and the ultrasonography of the major salivary glands.

The COVID-19 pandemic has affected lives and professions worldwide. We aimed to determine the behavior of dentists during the lockdown in Central Italy through an online survey. We demonstrated that the most frequent of urgencies, not otherwise manageable through telemedicine, was dental pulp inflammation. Although a statistically significant increase in the use of some of the personal protective equipment (PPE) from pre to during lockdown was shown, dentists were afraid of being infected during the dental procedures. Moreover, we showed that digital dentistry, telemedicine, use of the rubber dam, distancing of the appointments and further structural changes at the dental office are necessary to reduce the contagion among dentists and patients. No significant differences were shown between gender.

Transmission pathways of SARS-CoV-2 are aerosol, droplet and touching infected material. The diffusion of the virus contagion among people is easier in indoor location, but direct detection of SARS-CoV-2 in air or on surfaces is quite sparse, especially regarding public transport, while it would be important to know how and if it is safe to use them. To answer these questions we analysed the air and the surfaces most usually touched by passengers inside a city bus during normal operation, in order to understand the possible spreading of the virus and the effectiveness of the protective measures. The measurements were carried out across the last week of the lockdown and the first week when, gradually, all the travel restrictions were removed. The air and surface samples were analysed with the RT-PCR for the detection of SARS-CoV-2 virus. After two weeks of measurements and more than 1100 passenger travelling on the bus the virus was never detected both on surfaces and on air, suggesting that the precautions adopted on public transportation are effective in reducing the COVID-19 spreading.

Marginal bone loss (MBL) is a key factor in long-term implant success rate. Among the different factors that influence MBL, it is the different implant shoulder designs, such as scalloped or non-scalloped, which have been widely studied on screw retained but not on cemented retained implants. Thus, the aim of the present study was to evaluate the MBL around scalloped and non-scalloped cemented retained dental implants after 4 years of loading, in humans. A total of 15 patients were enrolled in the present study. A radiographic and clinical examination was performed after implant placement (T0) and after 4 years from it (T1). The results demonstrated a differential MBL (T1-T0) of 2.436 &plusmn, 1.103 mm and 1.923 &plusmn, 1.021 mm, respectively for test (scalloped) and control (non-scalloped) groups with a statistically significant difference between them. On the other hand, no statistically significant differences were found between the groups in terms of prosthetic complication and abutment decementation, whilst ceramic crowns chipping was shown in both groups. In conclusion, the use of a scalloped platform did not provide better results on the maintenance of MBL after 4 years follow-up. In this study, this probably was determined by multiple factors, among which was the subcrestal insertion of scalloped implants.

Periodontal disease (PD) is an inflammatory condition of the tissues supporting the teeth, which is widespread among the adult population. Evidence shows a relationship between PD and vitamin D levels, which is involved in the regulation of bone metabolism, mineral homeostasis, and inflammatory response. This study aimed to perform a simultaneous evaluation of inflammatory mediators and vitamin D levels in saliva in periodontopathic patients to better understand their role in periodontal disease. In this observational study, clinical periodontal parameter examination was performed for each patient. Moreover, the saliva levels of 25(OH)D3, TGF&beta, IL-35, IL-17A, and MMP9 were evaluated using an ELISA assay. An increase in TGF&beta, IL-35, MMP9, and IL-17A salivary levels and a reduction in 25(OH)D3 levels were observed in periodontopathic patients with respect to the healthy controls. The present study revealed significant positive correlation between cytokines and highly negative correlation between 25(OH)D3 and salivary cytokine levels. Further studies are needed to better understand if salivary cytokines and vitamin D evaluation may represent a new approach for detection and prevention of progressive diseases, such as PD.

Adhesive restorations have been shown to guarantee excellent performance and longevity, although this comes with some disadvantages. Among these, the vulnerability of dentine to different agents has been widely evaluated. The aim of this study was to evaluate the possible penetration of impression materials into freshly cut dentine. Dentine from 27 teeth was impressed with polyether (Impregum Penta L) (nine teeth) and with polyvinyl siloxane (Aquasil Ultra LV) (nine teeth). The surface of nine teeth after the impressions were used as the control. Specifically, the extroflections caused by the imprinting of the dentinal tubules on the impression material, the so-called impression tags, were measured. Furthermore, the presence of the material inside the tubules was examined. Scanning electron microscopy analysis showed material tags for all of the experimental groups. The mean lengths (&plusmn, SD) were 22.6 (&plusmn, 11.0) &micro, m for polyether, 21.8 (&plusmn, 12.8) &micro, m for polyvinyl siloxane and 11.3 (&plusmn, 7.0) &micro, m for the tooth control, with mean diameters (&plusmn, SD) of 2.8 (&plusmn, 0.5), 2.4 (&plusmn, 0.7) and 3.1 (&plusmn, 0.7) &micro, m, respectively. Fractal analysis showed fractal dimensions of 1.78 (&plusmn, 0.03), 1.77 (&plusmn, 0.03) and 1.71 (&plusmn, 0.03), respectively. These data demonstrated that the impression materials can remain inside the dentinal tubules, which can adversely affect the adhesive procedures.

Microbial contamination could compromise the stability of dental implants increasing the risk of inflammatory reactions in the surrounding soft tissues. In this human, randomized, double-blind, clinical study, the presence of Porphyromonas gingivalis on the healing abutment and the inflammatory infiltrate surrounding peri-implant soft tissues were investigated. Experiments were done in order to clarify the effect of 0.20% chlorhexidine (CHX) versus placebo, applied during each rehabilitation stage. Thirty patients (15 per group) were included. The load of adhering P. gingivalis on the healing screw were quantified by quantitative Polymerase Chain Reaction (qPCR) Taq-Man. Immunohistochemical analysis was carried out on the gingival biopsy. Moreover, clinical data were recorded. Analysis of variance and the Holm&ndash, Sidak test was used to evaluate differences between groups. The results showed a significant low presence of P. gingivalis load in healing abutments belonging to the 0.20% CHX group. Overall, the differences in terms of P. gingivalis DNA copy number between two groups were statistically significant (p &lt, 0.01). All implants showed very low plaque and bleeding scores, but the placebo group appeared to have the highest expression of inflammation markers for T Lymphocytes, B Lymphocytes and macrophages Cluster definitions (CD3, CD20 and CD68). The use of 0.20% CHX could be recommended in all clinical procedures as it reduces significantly P. gingivalis load and host inflammatory response around implants.

Introduction. Peri-implant marginal bone loss (MBL) seems to be more pronounced in the first year of loading despite all the studies and changes implemented to reduce it. Among the different causes, the presence of a microgap makes the interface between fixture and abutment colonizable by bacteria, causing an inflammatory response and consequent bone resorption. To reduce this several local antiseptics like chlorhexidine digluconate (CHX) were used after surgical procedures. Aim. The objective was to radiologically compare the MBL when a 0.20% CHX gel or a placebo gel was applied to the implant-abutment interface during all surgical and prosthetic phases and for a follow-up period up to 12 months. Method. 32 patients (16 for each Group A and B) were enrolled and rehabilitated with a single implant (Cortex classic, Cortex, Shalomi, Israel). During each of the clinical stages a gel containing 0.20% CHX (Plak ®Gel; Polifarma Wellness Srl, Rome, Italy) or a placebo gel (Placebo, Polifarma Wellness Srl, Rome, Italy) was used as indicated by the randomization chart. In order to compare radiographic modification intraoral radiographs was taken. Also, clinical data regarding implant or prosthetic failure and gingival index were recorded. Data were presented as means and standard deviations (SD) and used for the statistical analysis. Results. All implants showed no bleeding on probing and a very small plaque score at the 1 year of follow-up. MBL was statistically significantly different between the groups in every stage. Conclusion. Results obtained showed that the use of CHX gel inside the connection significantly reduces MBL during the first year. A rigid disinfection protocol with 0.20% CHX from the time of implant insertion to crown delivery is recommended to reduce host inflammatory response and consequently MBL. This trial is registered with ClinicalTrials.gov Identifier: (Registration Number: NCT03431766).

Purpose The aim of this retrospective study was to evaluate the incidence of inferior alveolar nerve (IAN) lesion and duration of sensitivity disturbances after the insertion of dental implants. Methods One thousand sixty-five patients (mean age: 58.9 years) enrolled between February 2004 and July 2015 with partial or full mandibular edentulism were selected to receive dental implants for oral rehabilitation. A total of 3025 implants were placed. After surgical procedures, controls were scheduled at suture removal, that is, 10 days after surgery, and repeated at intervals of 1, 3, and 6 months, and comprised patient interview, clinical examination, and sensitivity tests. Results Only 23 (2.2%) of the 1065 patients presented sensitivity disturbances 1 month after implant insertion, and only 2 (0.19%) after 6 months, though a complete recovery was observed in these patients within 13 months. Conclusions Considering the debilitating effects resulting from IAN lesion and the complexity of the therapeutic diagnostic protocols, all patients undergoing oral rehabilitation through dental implants should be evaluated with CBCT imaging.

OBJECTIVE The present prospective study aimed to more precisely identify the time points of bone changes around hybrid titanium implants up to 30 months of follow-up. MATERIALS AND METHODS Twelve hybrid T3 implants (Biomet 3i) were placed in 9 healthy patients with the 2-stage surgical approach. Standardized digital Rx were taken at implant insertion (T0); healing-abutment connection after 3.1 ± 0.2 weeks (TX); loading stage after 7.5 ± 0.6 weeks (T1); after 12 months (T2); and after 30 months (T3) of functional loading. The marginal bone loss was digitally measured. RESULTS The mean marginal bone loss was 0.76 ± 0.37 mm after 30 months. More than 60% (0.42 ± 0.29 mm) of the bone loss took place at healing-abutment connection (TX-T1). No statistically significant bone loss was found between T1-T2 and T2-T3, after 12 and 30 months, respectively. Approximately 40% of bone loss (0.34 mm) was noted between T1 and T3 (P < 0.05), which corresponds to the loading period. CONCLUSIONS The implant-oral environment connection represents a critical step point in crestal bone loss. The amount of marginal bone loss, measured after 30 months of loading (T1-T3), was much less than that reported in the literature, showing that correct loading has a minor impact on the periimplant bone remodeling as compared to surgical implant reopening.

The loosening of an abutment screw is one of the most frequent complications in implant-prosthetic rehabilitation, especially for single-crown cemented prostheses. This complication is due to several mechanical factors including type of connection, abutment-screw geometry, settling effects, and cyclical load. The purpose of the present in vitro study was to compare and associate different times of retightening with reductions in preload losses. We evaluated 40 internal hexagon dental implants and 40 external hexagon dental implants, with their related abutment screws. The implants were embedded in acrylic resin in cylindrical polyvinyl chloride tubes (26 mm diameter, 20 mm height). The abutments were fixed to the implants with screws to an initial torque of 35 Ncm using a digital torque meter with decimal precision. Two different types of connection were randomly divided in 4 subgroups of 10 samples each. One subgroup was used as control. The test groups underwent retightening to the same initial torque at increasing times from initial torque application for tightening of the abutment screws, to their retightening at 2 minutes, 5 minutes, and 10 minutes. The retightening time of 2 minutes shows significantly reduced preload loss. Randomized clinical trials are strongly required to provide clinicians with a beneficial standardized protocol of retightening that can be applied in routine clinical practice.

Immediate dentin sealing (IDS) is an advantageous approach for realizing adhesive restorations, but it interferes with the polymerization of impression material due to the oxygen-inhibition layer (OIL), which leaves residues of impression material on the teeth. The aim of this study is to identify a clinical surface cleaning protocol after IDS in order to achieve defect-free impressions. Sixty extracted human teeth were cut to expose fresh dentin and the IDS protocol was performed. Samples were divided into six groups where different surface cleaning protocols were made before taking impressions: G1S and G1P groups, IDS and silicone (S) or polyether (P) impressions, G2S and G2P, treatment with prophy paste and impressions, G3S and G3P, final cleaning phase with surfactant agent and impressions. Teeth were evaluated with a scanning electron microscope to identify the areas (expressed in mm2) where residual impression material was present. The results demonstrate a reduction of residues in the G2 groups and the total disappearance in G3 groups with statistically significant differences between them. Superficial cleaning protocols with the prophy paste and surfactant agent lead to the elimination of the interaction with impression materials and OIL. These results suggest a safe clinical protocol for obtaining defect-free impressions after IDS.

Although, the high success rate of implant rehabilitation treatment, the biological complications such as bone loss and peri-implantitis are still present. The creation of a coronal biological seal between the implant and the oral tissues seems to be a crucial point on preserving dental implants. The objective of this study was to immunohistochemically analyze the behavior of peri-implant soft tissues around a new implant healing-abutment surface on humans. A total of 30 soft tissue biopsies were collected after a healing period of 30 (&plusmn, 7) days, to analyze the expression of inflammatory (cluster of differentiation 63 (CD63), human neutrophil peptides 1&ndash, 3 (HPN1&ndash, 3)) and junctional (E-cadherin, occludin, and &beta, catenin) markers, on soft tissues around laser treated and machined alternated healing abutments. The evaluation demonstrated the whole area of the soft tissues adherent to the laser treated surface with a regular morphology. While several stress hallmarks in correspondence of machined surfaces were shown such as: a) An irregular, disrupted, and discontinued basal membrane with an increased inflammation evident both the epithelial and connective tissues, b) the absence or defective proper keratinization process of the external layer, and c) damages in the cell to cell interaction. In conclusion, the laser treated surface is preferable to maintain the integrity and functionality of the gingiva epithelium.

OBJECTIVES The study aimed to evaluate the effects of different titanium surface treatments on blood clot extension (bce). METHODS A total of 54 titanium disks with machined surface (M), laser-conditioned surface (L), and grit-blasted surface (S) were used in the present study. The surface characteristics such as contact angles and the microroughness were determined on each group (n = 4). To evaluate the bce, 0.1 mL of human blood was dropped onto the surface of each specimen and left for 7 minutes at room temperature. After fixation, dehydration, and gold sputtering treatments, the specimens were observed under scanning electron microscope. The bce values were expressed as percentage of specimen surface covered by blood clot. RESULTS The surface roughness (Ra ± standard deviation [SD]) was 0.75 ± 0.02 μm for M, 0.25 ± 0.02 μm for L, and 1.30 ± 0.03 μm for S. The contact angles measured in static conditions (WCA ± SD) were 71 ± 5.4° for M, 107 ± 6.6° for L, and 91 ± 7.2° for S. Regarding the bce (bce ± SD) of M samples (65.5 ± 4.3%) was statistically lower compared with both L (83.4 ± 5.1%) and S samples (72.4 ± 4.7%) (P

Administration of local anesthetics is daily routine for most dental practitioners. Normally, the effect is achieved, and no adverse effects are seen. In this article, the authors describe the complications of immediate, intense and shooting pain, numbness, and marked pallor of the cheek, which occurred during infiltration of a local anesthetic in buccal vestibule infiltration. The patients moved suddenly because of pain and marked pallor of the cheek near the root of the nose and lower eyelid pallor was observed. The pain was very short and the injection was performed again after a few minutes. Two patients also reported an alteration of vision or paralysis of the extra-ocular muscles and drooping eyelid due to paralysis of the levator palpebrae superioris muscle and signs of numbness in the infraorbital area on the same side as the anesthesia. While 3 patients were also apprehensive and started to scare with heart palpitations, as they did not understand what was happening. Probably the anesthetic solutions were injected into an intravascular artery and passed from the extraosseous branch of posterior superior alveolar artery through to the infraorbital artery, which could produce the clinical signs observed in the present study. At the same time, the inoculation of anesthetic in the artery could be grounds for legal disputes for the dentist. In fact, in the absence of vascular disease, anomalies documented by the dentist, they would, however, respond to professional liability and be liable for damages caused to the patient. In conclusion, despite the fact that this condition requires no treatment, it could lead to the recognition of clinical signs in patient with injection of local anesthesia into the artery. At the same time, the inoculation of anesthetic in the artery could be grounds for legal disputes for the dentist.

Statement of the problem Polyvinyl siloxane materials of various consistencies have been tested to reduce defects commonly associated with different definitive impression techniques. Purpose The purpose of this in vitro study was to compare the number of visible defects within the surface of a new 3-phase, 2-step impression injection technique with the number found in the monophase and in the conventional 2-phase, 1-step and 2-phase, 2-step impression techniques. Material and methods Two complete crown abutment preparations were impressed 10 times for each of these 4 techniques, which gave 20 abutment impressions for each group. The 3-phase, 2-step impression--injection technique included extra-light--body impression material added for the impression and injected after reinsertion. After the removal of all of these impressions, an examiner counted the number of open voids and bubble-like enclosed voids visible to the naked eye at a working distance of approximately 150 mm. Only the defects in the area of the prepared abutments were included in the assessment. Results The frequency of defects ranged from 100% of the impressions in the monophase group to 5% with the new 3-phase, 2-step impression injection technique. No statistical differences were seen between the two 2-phase (1-step and 2-step) impression techniques, although there were numerically fewer impressions with defects with 2 steps (45%) than with 1 step (55%). The 3-phase, 2-step impression injection technique had the greatest accuracy, with fewer specimens with defects (5%) than with either of the 2-phase techniques, although these differences did not reach statistical significance. Conclusions The 3-phase, 2-step impression injection technique provides improved defect-free reproduction of detail, showing fewer defects than other impression techniques.

Background: Many bone substitutes have been applied for sinus regeneration procedures, such as autogenous bone, inorganic bovine bone, porous and resorbable hydroxyapatite, tricalcium phosphate, bioactive glass, and blood clots. The aim of the present study was a tomographic, histological and histomorphometrical evaluation in humans, of specimens retrieved from sinuses augmented with MgHA/collagen-based scaffolds, after a healing period of 6 months. Materials and Methods: Eleven healthy patients and a total of 15 sinuses were included in this study. The maxillary sinuses were filled with commercial MgHA/collagen-based scaffolds (RegenOss) with a porous three-dimensional (3D) structure (Fin-Ceramica Faenza S.p.A., Faenza, Italy). These grafts have a composite design, that replicate the organization of bone structure, obtained by a technique in which a specific hybrid organic–inorganic composite is spontaneously built by a biological mechanism. The CBCT scans were done before the procedure, after the surgical protocol (T1), and 6 months after sinus surgery (T2) for implantology. Bone specimens were stored in 10% formalin solution, embedded in a glycolmethacrylate resin and sectioned by a high-precision diamond disc. Histologic and histomorphometric analysis were carried out to evaluate the graft reabsorption and bone healing. Results: The mean volume after graft elevation, calculated for each of the 15 sinuses, was 2,906 mm3 in the immediate postoperative period (5–7 days), ranging from 2,148.8 to 3,146.4 mm3. In the late postoperative period (6 months) it was 2,806.7 mm3, ranging from 2,010.9 to 3,008.9 mm3. The sinuses were completely healed and no residual MgHA/collagen-based scaffolds were visible. Osteoblasts appeared actively secreting bone matrix and marrow spaces contained moderate numbers of stromal cells and vascular network. Osteoblasts were observed actively secreting osteoid matrix. The tissues present in the samples were composed of 1.9 ± 1.9% of lamellar bone, 36 ± 1% of woven bone and 58 ± 3.8% of marrow spaces. Conclusion: Mg-MgHA/collagen-based scaffolds can successfully be used for sinus augmentation procedures.

Background By mixing hydroxyapatite (HA) and tricalcium phosphate (TCP), biphasic calcium phosphate ceramics can be obtained, and by varying their ratio it is possible to tailor the characteristics of the biomaterial. Purpose The aim of the present human study was to evaluate the histological and radiographical aspects of bone formation in maxillary sinus augmentation using a 30/70 HA-beta-TCP with a reticular structure. Materials and Methods A total of 12 patients, undergoing two-stage sinus augmentation procedure using HA-beta-TCP at a ratio of 30/70, were included in the present study. After a 6-month healing period, during implant insertion, radiographical analysis was performed, and then the bone core biopsies were harvested and processed for histology. Results At radiographic evaluation, the bone gain was on average 6.85 ± 0.60 mm. HA-beta-TCP 30/70 appeared to be lined by newly formed bone, with no gaps at the interface. The histomorphometric analysis revealed 26 ± 2% of residual grafted biomaterial, 29 ± 3% of newly formed bone, and 45 ± 2% of marrow spaces. Conclusions The present results indicate histologically the high biocompatibility and osteoconductivity of HA-beta-TCP 30/70, and clinically its successful use for sinus augmentation procedures.

Today, mini implants represent an additional choice for patients and surgeons. They are largely used as anchorage when a severely resorbed mandible is to be rehabilitated with an overdenture, their major advantages being flapless, painless surgery and easy placement in thin alveolar crests without any split-crest or bone-grafting procedure. Unfortunately, the literature provides little information on histomorphometric analysis of immediately loaded mini implants placed in the posterior region of the human mandible. The aim of the present in vivo research is to carry out a histologic evaluation of the bone surrounding 2 mini implants placed in human mandible and immediately loaded with an overdenture after 12 weeks. A patient who underwent extraction of 14 periodontally compromised teeth was selected for the present study. After the extractions, 2 mini implants with ball attachment were placed in sites 19 and 30. Mini implants were immediately loaded with a temporary immediate overdenture. Three months after the extractions, the mini implants were harvested and processed for light and scanning electron microscopy. The bone-to-implant contact and the percentage of bone between the threads of the screw were, respectively, 86.3% and 72.6% for the right implant and 69.8% and 71.9 % for the left implant. Newly formed bone between the implant surface and the preexisting bone was present, with poorly represented medullary spaces. Under a scanning electron microscope it was possible to appreciate the presence of well-organized, newly formed lamellar bone with osteons in the areas near the implant body. From the present in vivo report it is possible to state that immediate load applied on mini implants, placed into the posterior regions of the mandible, leads to a clinically and histologically effective osseointegration.

The aim was to analyze the data about the effects on marginal bone resorption and implant failure rates between implants inserted with high or low insertion torque values.A systematic literature search until July 2015 was conducted. Data were summarized qualitatively in descriptive tables and quantitatively by performing random effects meta-analyses of effect sizes (ESs) for bone resorption and bone-to-implant contact (BIC) and relative risks (RRs) for implant failures. Risk of bias assessments were performed using the Cochrane tool for human studies and the SYRCLE's tool for animal studies.Four studies in humans and 6 quasirandomized animal studies were included. A total of 591 implants were evaluated qualitatively: 348 installed with high insertion torque (25 Ncm, up to 176 Ncm) and 243 implants inserted with low torque values (30-35 Ncm). No significant differences were detected for bone resorption (ES, 0.13; 95% confidence interval [CI], -0.12 to 0.38 in human studies; ES predictive interval from 35.03 to 34.50 in animal studies), implant failure (RR, 0.39; 95% CI, 0.01-20.77 in human studies; RR, 2.05; 95% CI, 0.19-21.71 in animal studies), or BIC (ES predictive interval from -3.84 to 5.13 in animal studies).The current review indicated that there is no significant difference in marginal bone resorption and implant failure rate between implants inserted with high or low insertion torque values.

Aim The aim of this work is to analyze by scanning electron microscopy implant components that have mechanically failed in vivo. Materials and methods Three clinical cases are presented relative to single lateral posterior restorations supported by implants and a case of a mandibular overdenture supported by two implants. In all the reported cases the presence of an incongruous occlusal load caused the fracture of the components of the implant supported restorations. Conclusion From the analysis of the cases examined in this study, it is deduced that the functional overload influences the biomechanical behavior of the prosthetic rehabilitation supported by an implant and may, in less fortunate cases, determine the failure following the fracture of the connecting screws and/or the fixture. How to cite this article Di Iorio D, Sinjari B, Feragalli B, Murmura G. Biomechanical Aspects In Late Implant Failures: Scanning Electron Microscopy Analysis of Four Clinical Cases. J Contemp Dent Pract 2011;12(5):356-360.

Platelet-rich fibrin (PRF) promotes tissue regeneration by releasing various growth factors. The palatal donor site of the epithelialized connective tissue (CT) graft significantly influences the patient's morbidity. The aim of this study is to compare the effects of PRF and gelatin sponge on the healing of palatal donor sites and the patient's morbidity.Forty patients with at least one site of Miller Class I or II gingival recession were treated by a coronally advanced flap with CT graft resulting from the de-epithelialization of a free gingival graft. In the test group (20 patients), a PRF membrane was placed over the palatal wounds; conversely, the 20 control group patients were treated with an absorbable gelatin sponge. Patients were monitored at 1, 2, 3, and 4 weeks after surgery for the complete re-epithelialization of the palatal wound (CWE), the alteration of sensitivity around the wound area, postoperative discomfort, and changes in feeding habits (CFH). Furthermore, the consumption of analgesics during the postoperative week 1 was assessed.The test group showed a significantly faster CWE (P0.001); 35% of the test patients showed CWE at the end of week 2 (controls, 10%), whereas at the end of week 3, all palatal wounds in the test patients epithelialized completely (controls, 25%). Similarly, test patients reported significantly less discomfort and CFH (P ≤ 0.02) and took a significantly lower dose of analgesics (P = 0.02).The PRF-enriched palatal bandage significantly accelerates palatal wound healing and reduces the patient's morbidity.

Objectives The aim of this study was to perform a 2 months clinical and histological comparison of autologous bone, porcine bone, and a 50 : 50 mixture in maxillary sinus augmentation procedures. Materials and methods A total of 10 consecutive patients, undergoing two-stage sinus augmentation procedures using 100% autologous bone (Group A), 100% porcine bone (Group B), and a 50 : 50 mixture of autologous and porcine bone (Group C) were included in this study. After a 2-month healing period, at the time of implant insertion, clinical evaluation was performed and bone core biopsies were harvested and processed for histological analysis. Results The postoperative healing was uneventful regardless of the materials used for the sinus augmentation procedures. The histomorphometrical analysis revealed comparable percentages of newly formed bone, marrow spaces, and residual grafted material in the three groups. Conclusion The clinical and histological results of this study indicated that porcine bone alone or in combination with autologous bone are biocompatible and osteoconductive materials and can be successfully used in sinus augmentation procedures.

The aim of this study was to evaluate the use of calcium sulfate (CaS) as a hemostatic agent after tooth extraction in patients with anticoagulant drug therapy. A total of 30 patients undergoing anticoagulant therapy (22 women and 8 men) with a mean age of 54.6 years (SD = 9.2 years), needing dental extractions, were selected for this study. They were divided into 2 groups, control (group 1) and test (group 2), in a randomized way. In group 1 patients, the postextraction socket was managed with obliterative suture only. Group 2 patients were treated with CaS placed into the postextraction sockets. All the patients did not interrupt the anticoagulant therapy during the dental treatment. The healing pattern was found to be approximately similar in all treatment groups, showing significant improvement at each consecutive visit. However, a statistically significant difference in the adequate hemostasis was evident between groups 1 and 2 (P = 0.0056). The use of CaS helped to control the bleeding from inside the socket, producing instantly a very good hemostasis. Further studies are necessary to confirm the simplicity, possibilities, and limits of the proposed procedure.

Chemical and physical properties of an implant surface have a major influence on the structure of peri-implant bone and thus may influence the clinical performance of the implant. This study aims to evaluate the bone microstructure around implants with and without added nanometer-sized calcium phosphate particles.An implant with dual acid-etched surface (control) and an implant with dual acid-etched surface and CaP nanoparticles (test) were placed in the posterior maxilla of 15 patients. Bone microstructure was evaluated for osteocyte density (OD), bone vessel volume density (BVVD), and bone mineral density (BMD).BVVD was 1.806 ± 0.05 for test implants and 1.533 ± 0.10 for control implants (P0.001). BMDlow was 17.4 × 10(4) µm(2) for test implants and 15.0 × 10(4) µm(2) for control implants (P = 0.025). Results from the BMDhigh comparison, test versus control, were not statistically significant (P0.05). OD was 575.6 ± 63.7 mm(2) for test implants and 471.2 ± 61.9 mm(2) for control implants (P0.001).After 8 weeks of healing, the bone microstructure around test implants appeared to be significantly more organized. Clinical implications of these results include shortened healing time and indication for earlier loading protocols.

Prosthetic rehabilitation improves the patient's quality of life and oral health. The purpose of the present study was to assess the production of volatile sulfur compounds (VSCs) using Oral Chroma™ in patients wearing provisional and permanent fixed prosthesis, who were treated or not, with supportive non-surgical periodontal therapy. A total of 10 healthy patients not affected by periodontal disease and who needed the restoration of at least two edentulous single sites were included in the present study. Registrations of VSCs were carried out with a Gas Chromatograph OralChroma™ (Oral Chroma™, Abimedical, Abilit Corp., Osaka, Japan) one month after placement of the provisional restoration (group 1) and one month after placement of the final restoration (group 3). After each measurement, professional oral hygiene was carried out both on patients with provisional (group 2) and permanent prostheses (group 4) and VSC values were registered. The results showed that there were no statistical significant differences in the VSC quantity between groups with temporary or permanent prostheses. Meanwhile, statistically significant differences were found in VCS values between groups before and after the professional health care session (p less than 0.05). Also it was observed that dimethyl sulphide (CH3)2S was present in all the study groups. The present preliminary study suggests that OralChroma™ produce a comprehensive assessment of VSC in the clinical diagnosis of halitosis and that professional oral hygiene seems to influence VSC production. However, further clinical long-term studies with a larger sample size are necessary for a better understanding of halitosis manifestation in patients wearing provisional and permanent fixed prosthesis.