Efficacy and safety of erythritol air-polishing in implant dentistry: A systematic review.

OBJECTIVES: Professional oral hygiene is essential to prevent peri-implant disease. Appropriate instruments should be employed for implant-supported restorations: they should effectively remove deposits without damaging dental implant surface. The aim of the present systematic review is to investigate the efficacy and safety of erythritol air-polishing in implant-supported rehabilitations, compared to alternative hygienic techniques. MATERIALS AND METHODS: The guidelines reported in the indications of the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) were employed for this systematic review. The focused question was: 'what is the effect of erythritol air-polishing on dental implant surfaces regarding its cleansing efficacy and/or safety?' The final online search was conducted on 13 August 2023; MEDLINE-PubMed, Scopus and Cochrane Library were employed. Comparative in vitro or in vivo original studies were included. RESULTS: The initial database search yielded 128 entries; the final selection comprised 15 articles. The risk of bias was evaluated using the Newcastle Ottawa scale (NOS), the Cochrane Handbook for Systematic Reviews of Interventions, GRADE method. Ultrasonic scaling with PEEK tips, glycine air-polishing and cold atmospheric plasma were the devices most frequently compared to erythritol powder in the included studies. Erythritol air-polishing appeared to be significantly more effective in reducing biofilm compared to other treatments, without causing any significant damage to the implant surface and peri-implant tissues, promoting a good biological response. CONCLUSION: Erythritol air-polishing showed promising results for professional oral hygiene in implant-supported restorations. According to this systematic review, it is effective and safe for removing biofilm from titanium dental implants.

Torque changes of anchorage units in preadolescent patients treated with a digitally designed tooth-borne expander anchored to deciduous vs. permanent molars.

AIM: To compare the effects on permanent or deciduous anchorage dental units in patients treated with a digitally designed palatal expander. METHODS: Inclusion criteria were the following: presence of maxillary transverse deficiency, no previous orthodontic treatment, no extractions, absence of agenesis, congenital pathologies and cranio-maxillofacial malformations. Twenty patients (11 males, 9 females, 11 ± 1.8 years) received a digitally designed and metal printed palatal expander anchored on first permanent molars and 1 activation per day for 30 days (Group 1). Twenty-one patients (12 males, 9 females, 8.6 ± 1.4 years) received a digitally designed and metal printed palatal expander anchored on second deciduous molars and 2 activations per day for 14 days (Group 2). Digital intraoral scans were taken before expansion and after device removal, and torque and the palatal transverse diameter were digitally measured. The FDI notation was used to indicate each tooth CONCLUSION: Less dental torque augmentation was produced in Group 2. RESULTS: Significant intragroup differences over time were found in Group 1 considering the torque of teeth 1.6, 1.4, 1.3, 2.1, 2.4, 2.5, 2.6. Significant differences between groups were found regarding the longitudinal change in torque of teeth 1.5, 2.4 and 2.5. Significant intragroup differences over time were found in both groups considering all transverse diameter parameters. No significant differences were found between groups in the transverse diameter modifications over time. CONCLUSION: Less dental torque augmentation was produced in Group 2.

Carbon fibre versus metal framework in full-arch immediate loading rehabilitations of the maxilla - a cohort clinical study.

Frameworks made of carbon fibre-reinforced composites (CFRC) seem to be a viable alternative to traditional metal frameworks in implant prosthodontics. CFRC provide stiffness, rigidity and optimal biocompatibility. The aim of the present prospective study was to compare carbon fibre frameworks versus metal frameworks used to rigidly splint implants in full-arch immediate loading rehabilitations. Forty-two patients (test group) were rehabilitated with full-arch immediate loading rehabilitations of the upper jaw (total: 170 implants) following the Columbus Bridge Protocol with four to six implants with distal tilted implants. All patients were treated with resin screw-retained full-arch prostheses endowed with carbon fibre frameworks. The mean follow-up was 22 months (range: 18-24). Differences in the absolute change of bone resorption over time between the two implant sides (mesial and distal) were assessed performing a Mann-Whitney U-test. The outcomes were statistically compared with those of patients rehabilitated following the same protocol but using metal frameworks (control group: 34 patients with 163 implants - data reported in Tealdo, Menini, Bevilacqua, Pera, Pesce, Signori, Pera, Int J Prosthodont, 27, 2014, 207). Ten implants failed in the control group (6·1%); none failed in the test group (P = 0·002). A statistically significant difference in the absolute change of bone resorption around the implants was found between the two groups (P = 0·004), with greater mean peri-implant bone resorption in the control group (1 mm) compared to the test group (0·8 mm). Carbon fibre frameworks may be considered as a viable alternative to the metal ones and showed less marginal bone loss around implants and a greater implant survival rate during the observation period.

Microarray expression in peri-implant tissue next to different titanium implant surfaces predicts clinical outcomes: a split-mouth study.

OBJECTIVES: This split-mouth study evaluated miRNA expression of tissues around implants with different surface treatments. MATERIAL AND METHODS: Each patient of the sample (five men and five women) received two implants (one control and one test) into an edentulous quadrant to support fixed partial dentures. The control implants (Osseotite) had a dual acid-etched (DAE) surface in the apical portion and a machined coronal part, test implants (Full Osseotite, FOSS) were completely DAE. Machined healing abutments were placed on control implants and DAE abutments on test ones. All implants were assigned codes for blinding. Standardized periapical radiographs were taken at baseline, 2 and 6 months, and 1 year after surgery. Plaque index (PI), bleeding on probing (BOP), and probing depth (PD) were recorded at 3 and 6 weeks, and 2, 3, 6, and 12 months post-implant placement. After 3 months, a mini-invasive sample of soft tissue was collected from seven patients (four women and three men) for miRNA microarray analysis. RESULTS: Control implants showed greater bone resorption (BR) and lower PI: this was not statistically significant. No statistically significant differences in BOP and PD appeared. miRNA modulated by implant surfaces as well as by other clinical conditions has been identified. miRNA microarray analysis revealed that: (i) implant sites with low PI and absence of BOP had a miRNA expression profile similar to those with plaque and absence of BOP; sites with high PI and high BOP had a different profile. (ii) Implant sites with BOP presented similar profiles independently from implant surface. (iii) Implant sites with high PI and normal BR differed from others for miRNA expression profile. (iv) Implant sites with normal BR despite high BOP differed from others. This profile resembled that of FOSS implants. (v) Implant surface affected BR; groups having similar BR clusterized differently according to the implant type. CONCLUSIONS: DAE surfaces induced lower BR and more plaque accumulation: This did not affect the health of soft tissues. miRNA analysis indicated that soft tissue inflammation is more related to gene expression profile than to plaque or to implant surface. Specific miRNA profile can protect implant sites from bleeding and BR irrespective of plaque accumulation.

Effects of pulsed electromagnetic fields on swelling and pain after implant surgery: a double-blind, randomized study.

The aim of this split-mouth, double-blind, randomized study was to determine whether pulsed electromagnetic field therapy (PEMF) can improve swelling and the management of pain after full-arch immediate loading implant surgery. Eleven patients were selected for the study. Each patient received four distal tilted implants in the upper or lower jaw and underwent full-arch immediate loading rehabilitation. After surgery, two PEMF devices were applied to each patient, one on each cheek. In a random manner, one of these PEMF devices was switched on (test side); the other served as a placebo (control side). Forty-eight hours after surgery clinicians estimated postoperative swelling through photographic documentation, comparing the condition before and after surgery, while pain was assessed using a verbal rating scale. The patient's degree of comfort in relation to the PEMF devices was analyzed by questionnaire using a numerical rating scale. No statistically significant difference was observed between the test and control sides for swelling or pain (P>0.05). Most of the patients did not present swelling or pain at 48h after surgery, regardless of whether the PEMF device was activated or not. Various outcomes were found in the comfort evaluation. Within the limitations of this study, PEMF does not reduce postoperative swelling or pain after implant surgery.

Gastric and masticatory performances in full-arch immediate loading rehabilitated patients.

Full-arch immediate loading implant rehabilitations provide patients with compromised dentition an effective treatment to improve their aesthetic and function. Aim of this prospective cohort study was to investigate the correlation between masticatory ability and gastric emptying rates among these patients. Ten subjects (five men and five women) with compromised dentition were tested in two occasions: before treatment and 30 days after the immediate loading rehabilitation. Masticatory ability was evaluated using the sieves test, and the gastric half emptying time (T(1/2)) was assessed by means of the 13C-octanoic acid breath test. A statistically significant increment (P < 0.005) in masticatory ability was found only in reference to the particles smaller than or equal to 4.75 mm, whereas the gastric emptying rate showed a statistically significant reduction between pre- and post-treatment (P = 0.003). A moderate negative correlation (rho = 0.64, P = 0.048) between the percentage change in masticatory ability and the percentage change in gastric emptying rate was evidenced. Patients with compromised dentition rehabilitated with full-arch immediate implant prostheses present a significant improvement of the gastric process.

Biphosphonates-associated osteonecrosis of the jaw: the role of gene-environment interaction.

Biphosphonate (BPN) are widely used in clinics to treat metastatic cancer and osteoporosis thus representing a problem not only for patients but also for workers involved in their preparation and administration. A similar exposure occurred years ago in match-making workers undergoing bone alterations similar to those consequent to BPN exposure. Osteonecrosis of the jaw (ONJ) is a main adverse effect related to BPN administration, which is performed in millions of patients worldwide for osteoporosis and cancer therapy, thus representing an emerging problem in public health. In susceptible patients, BPN induce severe, progressive, and irreversible degeneration of facial bones, resulting in avascular ONJ often triggered by dental surgery. BPN induced ONJ occurs in subjects depending on lifestyle factors of both environmental and endogenous origins. Exogenous risk factors include cigarette smoke, alcohol consumption, bacterial infections, and cyclosporine therapy. Endogenous risk factors include systemic diseases such as diabetes or hypertension and adverse polymorphisms of genes involved in metabolism (CYPs, MTHFR), thrombosis (Factor V, Prothrombin), and detoxification (MDR). Available molecular findings provide evidence that ONJ is related to risk-factors associated with environmental mutagenesis and gene-environment interactions. This issues may be useful to identify susceptible subjects by molecular analyses in order to prevent ONJ occurrence.

Tilted implants in the immediate loading rehabilitation of the maxilla: a systematic review.

Tilted implants have been proposed as an alternative to traditional protocols in the rehabilitation of edentulous maxillae. The aim of this meta-analysis was to evaluate the outcomes of upright and tilted implants supporting full-arch fixed dentures for the immediate rehabilitation of edentulous maxillae, after at least 1 year of function. An electronic search of databases and a hand search of relevant journals in oral implantology were performed according to PRISMA guidelines through August, 2011. The literature search yielded 1,069 articles. Eleven articles were available for analysis. A total of 1,623 implants (778 tilted, 845 upright) were inserted into the maxillae of 324 patients. Seventeen tilted (2.19%) and 16 upright implants (1.89%) failed during the first year. No significant difference in failure rate was found between tilted and upright implants (p value = 0.52). Marginal bone level results were obtained from 6 studies. A non-significant mean difference between tilted and upright implants was found with regard to bone loss. Tilted implants demonstrated a favorable short-term prognosis in full-arch immediate loading rehabilitations of the maxillae. Randomized long-term trials are needed to better elucidate long-term success of tilted vs. upright-positioned implants.

A comparison between two fourth generation apex locators.

AIM: The aim of this study was to evaluate ex vivo the accuracy of two fourth generation apex locators and compare the measurements obtained. METHODS: Forty single and multiroots of permanent teeth (i.e., sixty-two canals) without caries or restorations were selected. After determining the real canal length using a stereomicroscope and a digital calliper, we evaluated the accuracy of two fourth generation electronic apex locators (the Bingo 1020 and the Propex) by means of an experimental study model and an endodontic simulator. The experimental model uses a digital comparator to determine the root canal length to a precision of 0.001 mm, while the endodontic simulator replicates the normal clinical condition. The difference between the real length of each canal and that obtained with the two study models was calculated. RESULTS: In both experiments, the Bingo 1020 expressed a 94.35% and the Propex expressed a mean accuracy of 90.31% in positioning the file at ± 0.5 mm. CONCLUSION: The Bingo 1020 and the Propex apex locators are equally accurate and provide reliable measurements in calculating root canal length.

Sinus floor elevation using osteotomes or piezoelectric surgery.

The aim of this paper is to describe a technique for sinus floor augmentation with a 1-step crestal approach where the residual bone is ≤ 7.5mm. 36 implants were installed in 25 patients in the atrophic posterior maxilla immediately after sinus floor elevation. Sinus floor elevation was performed with a crestal approach using either osteotomes and burs or piezosurgery. Standardized intraoral radiographs were taken prior to surgery and 1 year after surgery. The mean residual bone height was 5.61 mm (range 3-7.5mm). The mean gain of sinus elevation was 6.78 mm (range 3.5-10mm) at 1 year after surgery. Two patients dropped out of the study. Of the 23 patients completing the study, one implant failed, whilst the remaining 33 implants were stable 12 months after surgery (cumulative survival rate 97%). A statistically significantly higher bone height was achieved with tapered implants compared with cylindrical implants (P<0.05). No statistically significant differences were found in bone level using osteotomes or piezosurgery. Piezosurgery was considered to provide less discomfort for the patient and greater convenience for the surgeon.

[Connections of the laterodorsal nucleus of the thalamus in the monkey. Study of efferents]. / Connexions du noyau latéro-dorsal du thalamus chez le singe. Etude des efférences.

Efferent pathways of the LD nucleus of the thalamus were studied in 6 Papio-papio baboons with the retrograde transport technique utilizing HRP. Injections were made in cingular and parietal cortex and hippocampal formation. Large projection from the LD to the cingular and subicular cortex were visualized as reciprocal connections. No pathway to parietal area 7 was found. The course of the fibers is via the fornix, the cingular bundle and the retro-lenticular portion of the internal capsule. The result of this study make it necessary to reconsider neuropathological hypotheses on memory.