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PURPOSE: HER2-low breast cancer (BC) is a novel entity with relevant therapeutic implications, especially in hormone receptor (HR) positive BC. This study examines whether HER2 mRNA through the 21-gene assay, Oncotype DX (ODX), can refine the diagnosis of HER2-low and HER2-zero, obtained by immunohistochemistry (IHC). METHODS: Between Jan 2021 and Jan 2023, 229 consecutive HR-positive HER2-negative early BC (T1-3 N0-1) have been characterised by IHC and ODX. HER2 status by IHC was either zero (IHC-0) or low (IHC-1 + and IHC-2 + /ISH-negative) while HER2-zero was further divided into HER2-null (IHC-0) and HER2-ultralow (IHC-1-10%). HER2 gene expression by ODX was negative if lower 10.7. RESULTS: The distribution of HER2 IHC was as follows: 53.3% HER2-0, 29.25% HER2-1 + , and 17.5% HER2-2 + . The clinicopathological characteristics were similar in the three groups, with higher PgR-negative rate in HER2-zero (13.9% vs 3% vs 5%). The distribution of RS was homogeneous in the three groups with the median HER2 gene expression of 9.20 [IQR: 8.70-9.60]. HER2 gene expression gradually increased as the IHC score, with substantial overlap. After adjusting for confounders, HER2-1 + and HER2 2 + had a significant positive correlation between HER2 gene expression and IHC [OR 1.42, 95% CI 1.21 to 1.68, p < 0.001; OR 1.96, 95% CI 1.61 to 2.37, p < 0.001] compared to the HER2-zero group. HER2 gene expression did not differ between HER2-null and HER2-ultralow subgroups. CONCLUSION: Due to the substantial overlap, the HER2 gene expression is unable to properly distinguish HER2-low and HER2-zero IHC whose accurate identification is critical in the context of HER2-negative BC.

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AIM: Osteotomies are performed in oral surgery with five kinds of cutting instruments: 1) burs (Tungsten carbide cylindric burs), 2-3) ultrasound Piezosurgery (type I and II), 4-5) and lasers (Er:YAG; Er,Cr:YSGG). This study compares the quality of cutting of every single instruments, evaluating accuracy (length, thickness, depth and morphology), velocity (number of passages and time) and entity of damage. METHODS: In vitro experiments with ten osteotomies were performed on one-hundred of cow ribs with each instrument. In vivo surgery was performed on New Zealand white rabbit: two osteotomies are made with all instruments on the mandible and on the shinbone, totalizing four osteotomies for each instrument. Samples are processed to be evaluated through histological exam at stereo microscopy. DISCUSSION: Results show a statistically significant variability on "thickness" (p value=0.001), "time" (p value=0.001), "depth" and penetration speed (p-value=0.001; p-value=0.001) and the "number of passages" (p-value=0.001). No differences have been observed in "length" (p-value=0.078). Histological analysis reveals that osteotomy performed with laser and Piezosurgery II generates major damage to osteocytes near cutting surfaces. CONCLUSIONS: Currently, purchase and management elevated costs, minor versatility of use, and long training times for equipments such as Piezosurgery and laser limit their general use, but remain advantageous in case of risky interventions near noble structures. Choice of device depends on experience maturated by operator in time, characteristics of operation and patient's clinical conditions.

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AIM: After implant-insertion, bone tissue, newly-formed on peri-implant crest, undergoes to a mild marginal osseous readjustment due to build-up of inflammatory cell tissue (ICT). The present study verifies the possibility to limit bone resorption by placing implant fixtures 0.5 mm outside cortical bone edge. METHODS: A clinically-controlled randomized study on 100 implants has been performed to compare early resorption process of implant fixtures placed 0.5 mm outside cortical bone edge with implant-fixtures inserted according to juxtacortical bone conventional protocols. RESULTS: After 6 months, bone implant level was higher with emersion approach (-1.01±0.54 mm, mean±SD) than with submerged treatment (-1.56±0.5 mm) (P<0.001). CONCLUSIONS: Factors to achieve an excellent result at mean-long term seem to be very good, even though the latter have to be confirmed by follow-up.

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AIM: Ankyloglossia, commonly known as tongue-tie, is a congenital oral anomaly characterized by a short lingual frenulum that may contribute to feeding, speech and mechanical problems. The purpose of this study is to compare the advantages of laser vis-à-vis conventional frenectomy in both intra- and post-surgical phases. METHODS: This study took into consideration two patients, who were respectively 9 and 10-year-old. The first one underwent a common surgical procedure. A Nd:Yap laser device with a micropulsed wavelength of 1340 nm and power of 8 watts was used for the second. The postsurgical discomfort and healing characteristics were evaluated. RESULTS: The results indicated that the Nd:Yap laser has the following advantages when compared to the conventional frenectomy: 1) soft tissue cutting was efficient, with no bleeding, giving a clear operative field; 2) there was no need to use sutures; 3) the surgery was less time-consuming; 4) there was no postsurgical infection and no need for analgesics or antibiotics; 5) wound contraction and scarring were decreased or eliminated; 6) despite the initial slowness of the healing process, the complete and final recovery was faster. CONCLUSIONS: Considering the above elements, it is possible to assert that the laser frenectomy has a series of unquestionable advantages if compared to the conventional surgical technique.

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AIM: The aim of this study was to evaluate the perception of pain after Computer-aided-implantology Implant Surgery (NobelGuideTM, Nobel Biocare, Göteborg, Sweden) compared to the conventional implant surgery. METHODS: Eighteen patients from dental and maxillo-facial clinic of Policlinico G. B. Rossi (Verona, Italy) have been recruited: 9 were treated with the NobelGuide™ Technique, and 9 with the conventional one (approved by Local Ethical Committee) After the operation, painkillers (Ibuprofene tablets of 400 mg) were prescribed to the patients. Patients were asked to answer a questionnaire during the postoperative days and to report on the Visual Analogue Scale form (VAS), the intensity of pain and the number of painkillers used. RESULTS: The VAS mean one day after the operation (peak of maximum pain) was 47.22 for the conventional technique, and 12.77 for the NobelGuide™ technique, and also the number of painkillers assumed is smaller for the NobelGuide™ technique. The 5th day after the operation all the patients treated with the NobelGuide™ Technique stopped painkillers and nobody felt pain, while the patients treated with the conventional technique felt more pain and for a longer period. They also took painkillers until the 7th day. CONCLUSIONS: Pain is minor and disappears more quickly with the Nobelguide™ Implant Surgery compared with the conventional surgical technique. Nobelguide™ Implant Surgery can reduce hospitalization improving the compliance of odontophobic patients towards implant therapy.

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The surface characteristics of dental implants play an important role in the osseointegration process. Over the years implant surfaces have been subjected to different treatments, including turning, plasma spraying, coating, sand blasting, acid etching, and anodization. FBR coating is a fully resorbable calcium phosphate (CaP) coating made of brushite, obtained by electrochemical deposition on titanium plasma-sprayed (TPS) implants; this bioactive layer may be totally resorbable in 6-12 weeks and once the FBR coating has been resorbed, the newly formed bone is in contact with the roughness of the TPS surface. Human biopsy of immediately-loaded implants is certainly the most definitive means of determining the occurrence of osseointegration. In this case series the histologic and histomorphometric features of the bone-implant interface are analyzed and discussed in 3 immediately restored implants, retrieved from human subjects at 8, 10 and 12 weeks, respectively. All 3 implants were osseointegrated, with a bone to implant contact (BIC) ranging from 54.4% to 70.1%. The FBR coating was resorbed and replaced by new bone. Osteoconduction was especially noticeable between the implant threads, where the pristine bone was removed during implant bed preparation. The results suggest that the resorption window of 6-12 weeks for the CaP coating seems to be confirmed at least in the human mandible, and that immediately loaded FBR-coated implants placed in the posterior mandible can achieve osseointegration within 6-12 weeks of loading.

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AIM: Prolonged contact (several hours) of nickel-titanium (NiTi) endodontic instruments with sodium hypochlorite has a considerable corrosive effect which reduces the instruments' resistance to fractures. The aim of this study was to verify whether short-term contact (several minutes, as is the case in clinical practice) produces the same effects. METHODS: Using a digital scanning microscope, the blade surfaces of three groups of ProTaper instruments were examined, particularly of the #1 Shaping File. The blade's file (but not their handles) were soaked in sodium hypochlorite heated to 50 degrees C for three different times compatible with times in clinical practice, rather for 2, 5 and 10 minutes; the files were then compared with a control group. RESULTS: The micro-photographs did not reveal any appreciable signs of corrosion on the file blades. CONCLUSIONS: It is evident, therefore, that using sodium hypochlorite as an irrigating solution in root canals, where it comes into contact with NiTi rotary endodontic instruments, does not alter the surface structure of the files through corrosion. Thus it is possible to conclude that, considering the length of time used in clinical practice, sodium hypochlorite does not cause any increase of risk of fracture to Ni-Ti rotary instruments.

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Replacement therapy with immediate postextraction single dental implants has gained wider acceptance in clinical practice. However, because bone tissue volume may be insufficient for primary stability and subsequent osteointegration, many dentists prefer delaying implantation 2 or 3 months later, which may lead to greater loss of vestibular bone tissue and worsen postextraction atrophy. To avert these problems, a new surgical technique has been developed that allows immediate loading on postextraction single implants and atrophic socket remodeling. Socket remodeling is known to occur when the extraction site is completely ossified, but, depending on the length of time since tooth extraction, surgical complications may still arise, resulting in suboptimal wound healing of the socket, with unacceptable esthetic and functional outcome.

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Ameloblastic fibroma (AF) is defined in WHO classification as a ''neoplasm composed of proliferating odontogenic epithelium embedded in a cellular ectomesenchymal tissue that resembles dental papilla, and with varying degrees of inductive change and dental hard tissue formation''. AF is a rather uncommon tumor, accounting for only 2.5% of all odontogenic tumors. AF is a true mixed tumor, in which the epithelial and ectomesenchymal elements are neoplastic. AF raises at any age, ranging from 6 months to 42 years (mean 14.6 to 15.5 years); it does not show sex predilection. The lesion occurs in nearly 70% of cases in posterior areas of the mandible. Patients exhibit swelling of the jaw; pain is not usually described. Authors present a clinical and surgical management of an early onset of a large mandibular ameloblastic fibroma in a 6-year-old girsl.

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AIM: The aim of the present study was to evaluate the bending properties of twisted file instruments, and compare them with other commercially available nickel-titanium (NiTi) instruments (Mtwo and Hero) manufactured with traditional methods. METHODS: Despite NiTi superelastic properties, flexibility of NiTi instruments is limited by size and taper. A new manufacturing process involving twisting of a ground blank combined with heat treatment has been developed by SybronEndo, aiming to produce a NiTI rotary file with superior flexibility: the Twisted File (TF). Experimental procedures strictly followed the testing methodology described in ISO 3630-1. Bending moment was measured when the instrument attained a 45 degrees bend. Data were collected and statistically analyzed. RESULTS: Results showed that TF were the most flexible instruments, with a significant improvement in flexibility (P< 0.05). ranging from 100% to 250% over the other tested instruments. Even if flexibility is also influenced by instruments design, such a great improvement is mainly related to the new TF manufacturing process. CONCLUSION: The flexibility is influenced by instruments design, such a great improvement is mainly related to the new manufacturing process developed by SybronEndo, which seems to play a major role in increasing the flexibility of TF instruments.

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Several previous studies have investigated the advantage of temperature on tissue-dissolving and antimicrobial properties of sodium hypochlorite. However, it is known that the chemical stability of sodium hypochlorite is adversely affected by exposure to high temperature. The purpose of this study was to investigate the effect of heating sodium hypochlorite to 50 degrees C on the stability of the solution. An iodometric titration test was used to evaluate the decomposition rates of heated and nonheated solutions over 30 days. Results showed that all specimens exhibited a minimal, gradual degradation versus time. However, no statistically significant difference (p < 0.05) was noted between the two groups. After 30 days, both heated and non-heated solutions maintained high available chlorine content and pH values consistent with excellent tissue-dissolving and antibacterial properties.

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The aim of this study was to assess the cytotoxicity of pure eugenol in an in vitro method by diluting it to various concentrations in alcohol and determining the maximum noncytotoxic concentration. We used solutions of eugenol and ethyl alcohol that are soluble in water in any given proportion. The cytotoxicity of the alcohol itself was determined by using a dose-response curve for concentrations of between 0.017 M and 1.7 M. Various strength concentrations (0.015 to 947 microM) of eugenol in alcohol were prepared; 20 microliters (0.34 M) of ethyl alcohol was added to 1 ml of cell medium. The experiment showed that pure eugenol is toxic for human gingival fibroblasts. Eugenol in an alcohol solution at concentrations of < 1.9 microM is noncytotoxic.

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Cell cultures of human gingival fibroblasts obtained from healthy patients were used to evaluate the toxicity of six different endodontic cements: AH-26, Pulp Canal Sealer, Rocanal-R2, Rocanal-R3, Bioseal, and Endomethasone. The toxicity was determined by measuring spectrophotometrically at 405 nm the colorimetric reaction of N-acetyl-beta-hexosaminidase, an endogenous enzyme, with the chromogenic substrate [p-nitrophenol-N-acetyl-beta-D-glucosamide (NAG)]. Severe cytotoxicity was observed in the 1- and 2-wk test solutions of AH-26. Pulp Canal Sealer and Endomethasone showed low cytotoxicity in the 1- and 2-wk test solutions at 24, 48, and 72 h. Moderate cytotoxicity was observed in the 1- and 2-wk test solutions of Bioseal, except at 48 and 72 h of 1-wk test solutions. Rocanal-R2 showed severe cytotoxicity in the 1-wk test solutions at 48 and 72 h, and in the 2-wk test solutions at 24, 48, and 72 h. Moderate cytotoxicity was seen in the 1- and 2-wk test solutions of Rocanal-R3 only at 24 h.

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En años recientes, ha sido propuesto el uso de fibras de carbono en cirugía reparadora de tendones y ligamentos, ya que dichas fibras incitaban una intensa reacción del tejido conjuntivo, con sustitución de las estructuras lesionadas y recuperación de la función afectada. El objeto del trabajo fue el análisis histológico de esa reacción fibroblástica bajo las siguientes condiciones experimentales: a) sistema in vivo: reemplazo quirúrgico total del tendón de Aquiles de ratas adultas por un grueso haz de fibras de carbono operando como tutor, y estudio histológico de la zona operada; b) sistema in vitro: en tubos Leighton, siembra de fibroblastos de embrión de rata acompañados de pequeños segmentos de fibras de carbono, con cosecha a los 1, 2 y 6 días de incubación a 37-C y examen ulterior por microscopías ópticas y electrónica de barrido. El estudio histológico de la zona operada a los 30 días de la intervención, mostró franca reacción tisular, caracterizada por aparición de células gigantes multinucleadas fagocitando pequeños restos de fibras de carbono, acompañadas de gran proliferación de capilares sanguíneos, fibroblastos y fibras colágenas. La reacción fue mucho más acentuada a los 90 y 120 días de la cirugía, observándose que amplios sectores antes ocupados por fibras de carbono habían sido reemplazados por masas de tejido conjuntivo fibroso. En cultivos celulares, la microscopía óptica mostró que los fibroblastos multiplicaban adhiréndose a las fibras de carbono. En muestras análogas, la microscopía electrónica de barrido precisó las características de...

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En años recientes, ha sido propuesto el uso de fibras de carbono en cirugía reparadora de tendones y ligamentos, ya que dichas fibras incitaban una intensa reacción del tejido conjuntivo, con sustitución de las estructuras lesionadas y recuperación de la función afectada. El objeto del trabajo fue el análisis histológico de esa reacción fibroblástica bajo las siguientes condiciones experimentales: a) sistema in vivo: reemplazo quirúrgico total del tendón de Aquiles de ratas adultas por un grueso haz de fibras de carbono operando como tutor, y estudio histológico de la zona operada; b) sistema in vitro: en tubos Leighton, siembra de fibroblastos de embrión de rata acompañados de pequeños segmentos de fibras de carbono, con cosecha a los 1, 2 y 6 días de incubación a 37-C y examen ulterior por microscopías ópticas y electrónica de barrido. El estudio histológico de la zona operada a los 30 días de la intervención, mostró franca reacción tisular, caracterizada por aparición de células gigantes multinucleadas fagocitando pequeños restos de fibras de carbono, acompañadas de gran proliferación de capilares sanguíneos, fibroblastos y fibras colágenas. La reacción fue mucho más acentuada a los 90 y 120 días de la cirugía, observándose que amplios sectores antes ocupados por fibras de carbono habían sido reemplazados por masas de tejido conjuntivo fibroso. En cultivos celulares, la microscopía óptica mostró que los fibroblastos multiplicaban adhiréndose a las fibras de carbono. En muestras análogas, la microscopía electrónica de barrido precisó las características de... (AU)

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A patient affected with Debrè-De Toni-Fanconi syndrome secondary to cystinosis, has been given doses of vitamin D metabolites. This resulted in a reduced plasma 1,25(OH)2D level. This data should confirm, as it has already been noted in literature. There is a defect in renal 1 alpha hydroxylation of 25OHD. The administration of 1 alpha dihydroxycholecalciferol has brought rapid improvement to severe metabolic bone disease. There are no noticed side effects.

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