Osteoblastic and Bacterial Response of Hybrid Dental Implants.

Bacterial infections in dental implants generate peri-implantitis disease that causes bone loss and the mobility of the dental implant. It is well known that specific ranges of roughness favor the proliferation of bacteria, and it is for this reason that new dental implants called hybrids have appeared. These implants have a smooth area in the coronal part and a rough surface in the apical part. The objective of this research is the physico-chemical characterization of the surface and the osteoblastic and microbiological behavior. One-hundred and eighty discs of titanium grade 3 with three different surfaces (smooth, smooth-rough, and completely rough) were studied. The roughness was determined by white light interferometry, and the wettability and surface energy by the sessile drop technique and the application of Owens and Wendt equations. Human osteoblast SaOS-2 was cultured to determine cell adhesion, proliferation, and differentiation. Microbiological studies were performed with two common bacterial strains in oral infection, E. faecalis and S. gordonii, at different times of culture. The roughness obtained for the smooth surface was Sa = 0.23 and for the rough surface it was 1.98 µm. The contact angles were more hydrophilic for the smooth surface (61.2°) than for the rough surface (76.1°). However, the surface energy was lower for the rough surface (22.70 mJ/m2) in both its dispersive and polar components than the smooth surface (41.77 mJ/m2). Cellular activity in adhesion, proliferation, and differentiation was much higher on rough surfaces than on smooth surfaces. After 6 h of incubation, the osteoblast number in rough surfaces was more than 32% higher in relation to the smooth surface. The cell area in smooth surfaces was higher than rough surfaces. The proliferation increased and the alkaline phosphatase presented a maximum after 14 days, with the mineral content of the cells being higher in rough surfaces. In addition, the rough surfaces showed greater bacterial proliferation at the times studied and in the two strains used. Hybrid implants sacrifice the good osteoblast behavior of the coronal part of the implant in order to obstruct bacterial adhesion. The following fact should be considered by clinicians: there is a possible loss of bone fixation when preventing peri-implantitis.

The Use of Human Sterilized Crushed Tooth Particles Compared with BTCP Biomaterial and Empty Defects in Bone Formation inside Critical Rabbit Calvaria Sites.

This study aimed to assess the bone regeneration of critical-size defects in rabbit calvaria filled with freshly crushed extracted teeth, comparing them with BTCP biomaterial and empty sites. Materials and methods: Twenty-one female New Zealand rabbits were used in this study. Two critical-size defects 6 mm in size were created in the skull bone, each with a 3 mm separation between them. Three experimental groups were evaluated: Group A (human sterilized crushed teeth granules alone), Group B (Bioner Bone, Bioner Sitemas Implantológicos), and Group C (unfilled defects). The animals were sacrificed at 4 and 8 weeks. Evaluation of the samples involved histological and histomorphometric analyses with radiographic evaluation. The histological evaluation showed a higher volume reduction in Group A compared with Group B (p < 0.05) and Control. Group A showed the highest values for cortical closure and bone formation around the particles, followed by Group B and Group C (p < 0.05). Within the limitations of this animal study, we can conclude that the use of human tooth particles leads to increased bone formation and reduced connective tissue in critical-size defects in rabbit calvaria when compared to BTCP biomaterial. The calvarial model is a robust base for the evaluation of different biomaterials.

Corrosion Resistance and Titanium Ion Release of Hybrid Dental Implants.

One of the strategies for the fight against peri-implantitis is the fabrication of titanium dental implants with the part close to the neck without roughness. It is well known that roughness favors osseointegration but hinders the formation of biofilm. Implants with this type of structure are called hybrid dental implants, which sacrifice better coronal osseointegration for a smooth surface that hinders bacterial colonization. In this contribution, we have studied the corrosion resistance and the release of titanium ions to the medium of smooth (L), hybrid (H), and rough (R) dental implants. All implants were identical in design. Roughness was determined with an optical interferometer and residual stresses were determined for each surface by X-ray diffraction using the Bragg-Bentano technique. Corrosion studies were carried out with a Voltalab PGZ301 potentiostat, using Hank's solution as an electrolyte at a temperature of 37 °C. Open-circuit potentials (Eocp), corrosion potential (Ecorr), and current density (icorr) were determined. Implant surfaces were observed by JEOL 5410 scanning electron microscopy. Finally, for each of the different dental implants, the release of ions into Hank's solution at 37 °C at 1, 7, 14, and 30 days of immersion was determined by ICP-MS. The results, as expected, show a higher roughness of R with respect to L and compressive residual stresses of -201.2 MPa and -20.2 MPa, respectively. These differences in residual stresses create a potential difference in the H implant corresponding to Eocp of -186.4 mV higher than for the L and R of -200.9 and -192.2 mV, respectively. The corrosion potentials and current intensity are also higher for the H implants (-223 mV and 0.069 µA/mm2) with respect to the L (-280 mV and 0.014 µA/mm2 and R (-273 mV and 0.019 µA/mm2). Scanning electron microscopy revealed pitting in the interface zone of the H implants and no pitting in the L and R dental implants. The titanium ion release values to the medium are higher in the R implants due to their higher specific surface area compared to the H and L implants. The maximum values obtained are low, not exceeding 6 ppb in 30 days.

Relevant Aspects of Titanium and Zirconia Dental Implants for Their Fatigue and Osseointegration Behaviors.

Osseointegration capacity and good mechanical behavior are key to the success of the dental implant. In many investigations, comparisons of properties are made using different dental implant designs and therefore the results can be influenced by the macrodesign of the dental implant. In this work, studies were carried out with the same dental implant model using different roughness and different materials-commercially pure titanium (grade 4) and zirconia. For this purpose, 80 smooth passivated titanium (Ti), 80 smooth zirconia (ZrO2), and 80 rough passivated titanium (Ti-R) dental implants were used. The samples were characterized by their roughness, wettability, surface energy, residual stresses, and fatigue behavior. The implants were implanted in minipigs for 4 and 12 weeks. The animals were sacrificed, and histological studies were carried out to determine the osseointegration parameters for each of the implantation times. Ti and ZrO2 dental implants have very similar wettability and surface energy properties. However, the roughness causes a decrease in the hydrophilic character and a decrease of the total surface energy and especially the dispersive component, while the polar component is higher. Due to the compressive residual stresses of alumina sandblasting, the rough dental implant has the best fatigue behavior, followed by Ti and due to the lack of toughness and rapid crack propagation the ZrO2 implants have the worst fatigue behavior. The bone index contact (BIC) values for 4 weeks were around 25% for Ti, 32% for ZrO2, and 45% for Ti-R. After 12 weeks the Ti dental implants increased to 42%, for Ti, 43% for ZrO2, and an important increase to 76% was observed for Ti-R implants. In vivo results showed that the key factor that improves osseointegration is roughness. There was no significant difference between ZrO2 and Ti implants without sandblasting.

Is There a Relationship Between Age, Personal Factors or Surgical Findings, and Outcome After Temporomandibular Joint Arthroscopy?

PURPOSE: The variables involved in prognosis after treatment of internal derangement (ID) of the temporomandibular joint (TMJ) are unclear. The purpose of this study was to estimate the frequency and identify which factors are associated with treatment success (or failure) among patients with ID managed with arthroscopy. MATERIAL AND METHODS: A retrospective cohort study was carried out of patients undergoing TMJ arthroscopy over a 9-year-period. The predictor variable was composed of a set of demographic, clinical, and operative findings, including, as primary variable, the patient's age. The primary outcome variable was based on the American Association of Oral and Maxillofacial Surgery (AAOMS) criteria of pain (measured by visual analogue scale (VAS)) and maximal interincisal opening (MIO) defined as VAS ≤ 3 and MIO greater 35 mm and grouped as success or failure. The improvement in pain and functional values were compared with the age by using the Pearson correlation coefficient, whereas categorical variables were tested using chi-squared analysis, and mean values were compared with Student t-test or ANOVA. Subsequently, a logistic regression model was used, and the odds ratios (OR) of the evaluated comparisons were calculated. RESULTS: A total of 212 patients were included in this study. In terms of arthroscopic findings, the presence of severe chondromalacia, adhesions or disc perforation (P < .001), was related with older patients. However, there was no statistically significant correlation between age and the postoperative improvement referred to pain or MIO. According to the AAOMS criteria, the procedure was successful in 54.24% of the cases. Two factors were related with a favorable outcome in the adjusted regression analysis: a higher presurgical MIO (OR 0.91, P < .001) and the presence of adhesions (OR 0.41, P = .003). CONCLUSION: Age has no influence on the outcome after arthroscopy. A higher presurgical MIO and the presence of adhesions provide, in the long-term, a favorable prognosis.

Another (Internal) Epineurium: Beyond the Anatomical Barriers of Nerves.

The epineurium has been accepted as the outer anatomical barrier of the peripheral nerves. Our objective was to characterize the microanatomy of the layers surrounding nerves using different tissue-specific staining methods. Two hundred forty-two cross sections of human sciatic and median nerves, and brachial plexuses of eight fresh unembalmed cadavers, were examined. The samples were fixed in formaldehyde solution and stained with hematoxylin-eosin, Masson's trichrome, or epithelial membrane antigen under standard conditions. Because epithelial membrane antigen only stains the perineurium, we demonstrated using hematoxylin-eosin and Masson's trichrome that there were different collagen layers inside and outside the nerves. All fascicles had a collagen layer that surrounded the perineurium and were in close contact with it, with no adipose tissue between them. Unlike the perineurium, this layer, an "internal epineurium," contained no cells, and it surrounded one or a small group of fascicles. Bundling these fascicles or small groups of fascicles together was the true epineurium, and between the true and internal epineurium, we consistently found an adipose-containing compartment. More proximal to this, the tibial and common peroneal nerves were bundled together by another collagen layer, the circumneurium, which also had a fat-cell-containing compartment deep to it. There were scattered collagen fibers among the adipocytes. Using tissue-specific staining, we were able to demonstrate a collagen layer, the "internal epineurium." Outside the nerves, we identified several fat-containing concentric compartments. Those compartments were limited by collagen fiber layers that were also similar to the epineurium. Clin. Anat. 33:199-206, 2020. © 2019 Wiley Periodicals, Inc.

Bacterial Adherence Around Sutures of Different Material at Grafted Site: A Microbiological Analysis.

Closure of the surgical incision has been the primary function of sutures since their introduction. However, whatever the type, they are known to carry bacteria, which can be a source of infection. Five types of surgical sutures, Gut, Silk, Vicryl, PTFE, and Polyamide, were selected and tested on their ability to carry aerobic and anaerobic bacteria and were rated on the basis of forming colony-forming units (CFUs). Aerobic bacteria grown around gut sutures showed minimum CFUs (≈30 × 104/suture). Though very less anaerobic bacteria growth was seen among all tested suture materials, it was maximum around Vicryl and polyamide sutures. Every suture material is capable, albeit not equally, of holding bacterial biofilm formation, which can be a source of surgical site infection.

Can the Macrogeometry of Dental Implants Influence Guided Bone Regeneration in Buccal Bone Defects? Histomorphometric and Biomechanical Analysis in Beagle Dogs.

The aim of this experimental animal study was to assess guided bone regeneration (GBR) and implant stability (ISQ) around two dental implants with different macrogeometries. Forty eight dental implants were placed within six Beagle dogs. The implants were divided into two groups (n = 24 per group): G1 group implants presented semi-conical macrogeometry, a low apical self-tapping portion, and an external hexagonal connection (whereby the cervical portion was bigger than the implant body). G2 group implants presented parallel walls macrogeometry, a strong apical self-tapping portion, and an external hexagonal connection (with the cervical portion parallel to the implant body). Buccal (mouth-related) defects of 2 mm (c2 condition) and 5 mm (c3 condition) were created. For the control condition with no defect (c1), implants were installed at crestal bone level. Eight implants in each group were installed under each condition. The implant stability quotient (ISQ) was measured immediately after implant placement, and on the day of sacrifice (3 months after the implant placement). Histological and histomorphometric procedures and analysis were performed to assess all samples, measuring crestal bone loss (CBL) and bone-to-implant contact (BIC). The data obtained were compared with statistical significance set at p < 0.05. The ISQ results showed a similar evolution between the groups at the two evaluation times, although higher values were found in the G1 group under all conditions. Within the limitations of this animal study, it may be concluded that implant macrogeometry is an important factor influencing guided bone regeneration in buccal defects. Group G1 showed better buccal bone regeneration (CBL) and BIC % at 3 months follow up, also parallel collar design can stimulate bone regeneration more than divergent collar design implants. The apical portion of the implant, with a stronger self-tapping feature, may provide better initial stability, even in the presence of a bone defect in the buccal area.

Comparison of Different Bone Filling Materials and Resorbable Membranes by Means of Micro-Tomography. A Preliminary Study in Rabbits.

The purpose of this work was to evaluate the behavior of different membranes and bone filling materials used to fill critical defects in rabbit calvaria. Four defects were prepared in the cranial calvaria of female rabbits. They were randomly divided into three subgroups according to the type of barrier membrane to be used. Four animals carried cross-linked bovine collagen membranes (Mem-Lok, Bio-Horizons, Birmingham, AL, USA)), four human fascia lata membranes (Tissue, Inbiomed SA, Córdoba, Argentina) and four human chorioamniotic membranes (Tissue. Inbiomed SA, Córdoba, Argentina). The defects were filled with the deproteinized bovine bone particulate Bio-Oss® (Geistlich-Pharma AG, Wolhusen, Switzerland), with particulate human hydroxyapatite MinerOss® (Bio-Horizons, Birmingham, AL, USA), with particulate dental material (Tissue Bank Foundation, Inbiomed S.A., Córdoba, Argentina), and the last one was left without the addition of filler material. In the first group of four specimens, a resorbable cross-linked bovine collagen membrane was placed over the skull and defects, without additional fixing. In the second group, a human fascia lata membrane was placed, without additional fixing. In the third group, a human chorioamniotic membrane was placed, without additional fixing. The animals were sacrificed at 4 and 8 weeks. The highest percentages of relative radiological density (average) were recorded considering the amnio-chorionic membranes (83.63%) followed by collagen (81.44%) and finally the fascia lata membranes (80.63%), but the differences were not statistically significant (p > 0.05). The sites grafted with a decellularized tooth (96.83%) and Bio-Oss (88.42%), recorded the highest percentages of radiological density but did not differ significantly from each other (subset 2). The three membranes used did not show statistical differences between them, in any of the two time periods used. There were statistical differences between the filling materials evidencing the presence of a large quantity of calcified material in the defects treated with particulate tooth and deproteinized bovine bone and while smaller amounts of calcified material were registered in the case of defects treated with human hydroxyapatite and those that were not treated.

Tratamiento de la ránula sublingual: revisión de la literatura. A propósito de un caso / Relationship between treatment of sublingual ranula: literature review. A case report

El objetivo de este trabajo es conocer las principales técnicas para el tratamiento de la ránula sublingual, llevando a cabo una revisión de la literatura existente a propósito de un caso clínico. Con respecto al caso clínico se trata de una paciente mujer de 20 años que acude a consulta por aumento de tamaño del suelo de la boca de unos 3x5 cm. Al realizar la resonancia magnética, se observa una lesión quística en la región sublingual derecha. Se planifica cirugía de escisión radical, extirpando la glándula sublingual derecha y la lesión. Se pauta como tratamiento antibiótico amoxicilina-ác. clavulánico 875/125 mg y antiinflamatorio metilprednisolona 40 mg y dexketoprofeno 50 mg. Como conclusión la técnica más utilizada, hoy en día, es la cirugía radical, seguida de la micromarsupialización y técnicas modernas mínimamente invasivas

The objective of this study is to know the main techniques for the treatment of the sublingual ranula, through a literature review about a clinical case. With regard to the clinical case, this is a 20 year old female patient present at medical clinic for an increase size of the floor of the mouth of about 3x5cm. When performing a magnetic resonance, observe a cystic lesion in the right sublingual region. Radical excision surgery planned, removing the right sublingual gland and the lesion. It is prescribed as antibiotic treatment amoxicillin-clavulanic acid 875/125 mg and anti-inflammatory methylprednisolone 40 mg and dexketoprofene 50 mg. In conclusion, the most used technique, nowadays, is the radical surgery, followed by the micromarsupialisation and minimally invasive modern technique

Study of Two Bovine Bone Blocks (Sintered and Non-Sintered) Used for Bone Grafts: Physico-Chemical Characterization and In Vitro Bioactivity and Cellular Analysis.

In this work, the physicochemical properties and in vitro bioactivity and cellular viability of two commercially available bovine bone blocks (allografts materials) with different fabrication processes (sintered and not) used for bone reconstruction were evaluated in order to study the effect of the microstructure in the in vitro behavior. Scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectrometry, mechanical resistance of blocks, mercury porosimetry analysis, in vitro bioactivity, and cell viability and proliferation were performed to compare the characteristics of both allograft materials against a synthetic calcium phosphate block used as a negative control. The herein presented results revealed a very dense structure of the low-porosity bovine bone blocks, which conferred the materials' high resistance. Moreover, relatively low gas, fluid intrusion, and cell adhesion were observed in both the tested materials. The structural characteristics and physicochemical properties of both ceramic blocks (sintered and not) were similar. Finally, the bioactivity, biodegradability, and also the viability and proliferation of the cells was directly related to the physicochemical properties of the scaffolds.

Particulated, Extracted Human Teeth Characterization by SEM⁻EDX Evaluation as a Biomaterial for Socket Preservation: An in vitro Study.

The aim of the study was to evaluate the chemical composition of crushed, extracted human teeth and the quantity of biomaterial that can be obtained from this process. A total of 100 human teeth, extracted due to trauma, decay, or periodontal disease, were analyzed. After extraction, all the teeth were classified, measured, and weighed on a microscale. The human teeth were crushed immediately using the Smart Dentin Grinder machine (KometaBio Inc., Cresskill, NJ, USA), a device specially designed for this procedure. The human tooth particles obtained were of 300⁻1200 microns, obtained by sieving through a special sorting filter, which divided the material into two compartments. The crushed teeth were weighed on a microscale, and scanning electron microscopy (SEM) evaluation was performed. After processing, 0.25 gr of human teeth produced 1.0 cc of biomaterial. Significant differences in tooth weight were found between the first and second upper molars compared with the lower molars. The chemical composition of the particulate was clearly similar to natural bone. Scanning electron microscopy⁻energy dispersive X-ray (SEM⁻EDX) analysis of the tooth particles obtained mean results of Ca% 23.42 0.34 and P% 9.51 0.11. Pore size distribution curves expressed the interparticle pore range as one small peak at 0.0053 µm. This result is in accordance with helium gas pycnometer findings; the augmented porosity corresponded to interparticle spaces and only 2.533% corresponded to intraparticle porosity. Autogenous tooth particulate biomaterial made from human extracted teeth may be considered a potential material for bone regeneration due to its chemical composition and the quantity obtained. After grinding the teeth, the resulting material increases in quantity by up to three times its original volume, such that two extracted mandibular lateral incisors teeth will provide a sufficient amount of material to fill four empty mandibular alveoli. The tooth particles present intra and extra pores up to 44.48% after pycnometer evaluation in order to increase the blood supply and support slow resorption of the grafted material, which supports healing and replacement resorption to achieve lamellar bone. After SEM⁻EDX evaluation, it appears that calcium and phosphates are still present within the collagen components even after the particle cleaning procedures that are conducted before use.

Influencia de la edad en los hallazgos y el resultado del tratamiento artroscópico de la disfunción temporomandibular. Un estudio basado en 162 casos / Influence of age on the findings and outcome of arthroscopic treatment of temporomandibular dysfunction. A study based on 162 cases

Introducción: El propósito del presente estudio fue analizar si los hallazgos artroscópicos y la mejoría clínica tras dicho tratamiento quirúrgico difieren en virtud de la edad de los pacientes afectos por disfunción temporomandibular. Material y métodos: Se revisaron de manera retrospectiva los datos correspondientes a los pacientes tratados durante 7 años en dos centros hospitalarios en los cuales el tratamiento artroscópico se realizó de acuerdo con el mismo protocolo. Se consideraron solo los pacientes con diagnóstico de bloqueo crónico (estadios IV y V, según clasificación de Wilkes-Bronstein). El estudio implicó el análisis de dos grupos de pacientes diferenciados: a) Grupo A menores de 45 años al diagnóstico, b) Grupo B mayores de 45 años al diagnóstico. Durante la fase diagnóstica del protocolo de artroscopia por disfunción temporomandibular, se recogieron los parámetros «sinovitis» y «condromalacia». Asimismo se analizó la presencia o no de adherencias y/o de perforación discal. En cuanto al resultado clínico del tratamiento de los pacientes, se consideró el dolor durante la función mandibular, la máxima apertura interincisal, el movimiento protrusivo y de lateralidad en sentido contralateral a la articulación afecta como variables de estudio. Dichos datos se consideraron durante el postoperatorio al mes, 3, 6, 9, 12 y 24 meses. El análisis de los datos se basó en un análisis de la varianza de una vía para las variables cuantitativas y el test de χ2 para el estudio de las variables cualitativas. Los valores se consideraron significativos para una p < 0,05. Resultados: La población de estudio incluyó 162 pacientes (Grupo A 90 pacientes, Grupo B 72 pacientes). Los hallazgos de sinovitis y condromalacia en fase avanzada fueron más frecuentes para el grupo B de estudio con diferencias estadísticamente significativas, mientras que los hallazgos de adherencias y perforación discal no difirieron entre ambos grupos. Tras la realización de artroscopia de la ATM, se observó un descenso significativo del dolor (desde el primer mes postoperatorio) junto con un incremento significativo de la máxima apertura interincisal (a partir de 3 meses de seguimiento poscirugía) en ambos grupos de estudio. Conclusiones: El tratamiento mediante artroscopia de la disfunción temporomandibular en fases avanzadas de la enfermedad produce una mejoría clínica tanto en pacientes mayores como menores de 45 años de edad. Los pacientes mayores de 45 años presentan cambios patológicos intraarticulares correspondientes tanto a sinovitis como a condromalacia en fases más avanzadas. Por el contrario, estos pacientes mayores no muestran un incidencia superior de otros signos de degeneración articular como presencia de adherencias o perforación discal

Introduction: The aim of this study was to analyse whether the findings and clinical improvement after arthroscopic surgical treatment were different according to the age of the patients affected by temporomandibular dysfunction. Material and methods: A retrospective review was performed on the data corresponding to patients treated arthroscopically over a 7-year period in two hospitals using the same protocol. Only patients with a diagnosis of chronic closed lock (stage IV and V, according to Wilkes-Bronstein classification) were considered. The study involved the analysis of two different patient groups: a) Group A under 45 years of age at diagnosis, b) Group B over 45 years of age at diagnosis. During the diagnostic phase of the temporomandibular dysfunction arthroscopy protocol, the parameters "synovitis" and "chondromalacia" were collected for the evaluation of the synovial membrane and joint surface, respectively. The presence or absence of adhesions and/or disc perforation was also analysed. Regarding the clinical outcome of the treatment of patients, pain during mandibular function, maximum inter-incisal opening, protrusive movement, and laterality in contralateral direction to the joint involved, were considered as study variables. These data were collected at 3, 6, 9, 12, and 24 months after the surgery. Data analysis was based on a one-way variance analysis for quantitative variables and the χ2 test for the study of qualitative variables. The values were considered significant for a p < .05. Results: The study population included 162 patients (Group A 90 patients, group B 72 patients). Pathological findings of advanced-stage synovitis and chondromalacia were more frequent for group B, with statistically significant differences, while findings of disc adhesions and perforation did not differ between both groups. After TMJ arthroscopy, a significant decrease in pain (from the first postoperative month) was observed, together with a significant increase in maximum inter-incisal opening (from 3 months post-surgery follow-up) in both study groups. The rate of patients undergoing re-arthroscopy or open joint surgery in post-surgery follow-up was higher in Group A patients. Conclusions: Arthroscopic treatment of temporomandibular dysfunction in advanced stages of the disease shows a clinical improvement in patients over and under 45 years of age. Patients over 45 years of age showed intra-articular pathological changes corresponding to both synovitis and chondromalacia in more advanced phases. In contrast, these older patients did not show a higher incidence of other signs of joint degeneration, such as adhesions or disc perforation. Patients over 45 years of age did not have any differences in the percentage of failure and/or re-operation after arthroscopic treatment of temporomandibular dysfunction, compared to younger patients

Influence of Implant Neck Design on Peri-Implant Tissue Dimensions: A Comparative Study in Dogs.

This in vivo study assessed (hard and soft) peri-implant tissue remodeling around implants with micro-ring and open-thread neck designs placed in a dog model. Twenty histological sections corresponding to four different implant designs that were placed in America Foxhound dogs were obtained from previous studies. All the implants had been placed under identical conditions and were divided into four groups: Group A, micro-rings on implant neck plus 0.5 mm refined surface; Group B, micro-rings on implant neck; Group C, open-thread neck; and, Group D, double-spiral neck. Eight weeks after surgery, the integrated implants were removed and processed for histological examination. Crestal bone loss and bone-to-implant contact was greater for micro-ring necks than open-thread necks. Soft tissues showed significant differences on both buccal and lingual aspects, so that the distance from peri-implant mucosa to the apical portion of the barrier epithelium was smaller in the micro-ring groups. So, in spite of generating greater bone-to-implant contact, implants with micro rings produced more bone loss than open-thread implants. Moreover, the outcomes that were obtained IPX implants smooth neck design produced less bone loss in the cervical area, following by Facility implants when compared with the other open thread and microthreaded implant designs. Implant thread design can influence on bone remodeling in the cervical area, related to bundle bone preservation.

Correction: Peri-Implant Behavior of Sloped Shoulder Dental Implants Used for All-On-Four Protocols: An Histomorphometric Analysis in Dogs. Materials 2018, 11, 119.

The authors would like to correct following typing and two images errors [...].

Evaluation of the Surrounding Ring of Two Different Extra-Short Implant Designs in Crestal Bone Maintanence: A Histologic Study in Dogs.

The aim of this study was to compare the implant stability and bone resorption and formation of two different extra-short implant designs with different diameter rings placed in a dog´s maxilla. Thirty-six extra-short, 5 mm diameter × 4 mm length (Short DM®, Bioner Sistemas Implantológicos, Barcelona, Spain), delayed implants were placed in each hemimaxilla of six dogs at the bone crest level. Eighteen implants of each design (wide and narrow ring) were installed. After 8 and 12 weeks of healing, histomorphometric analyses of the specimens were carried out to measure the crestal bone level values and the tissue thickness around the wide and narrow ring implant designs. In the microscopic analysis, less buccal bone resorption was observed in the narrow ring implants with a statistical significance (p < 0.001). For the peri-implant tissue thickness, the distance from the implant shoulder to the external portion of the epithelium was significantly higher for the implants installed with a wide ring with statistical significance (p < 0.001). Our findings suggest that the amount of peri-implant tissues (crestal bone loss) after remodeling over a period of 12 weeks was smaller in the narrow ring extra-short implant installed in the healed maxilla, compared with the wide ring extra-short implants.

The Use of Tooth Particles as a Biomaterial in Post-Extraction Sockets. Experimental Study in Dogs.

Objectives: The objective of this study was to evaluate new bone formation derived from freshly crushed extracted teeth, grafted immediately in post-extraction sites in an animal model, compared with sites without graft filling, evaluated at 30 and 90 days. Material and Methods: The bilateral premolars P2, P3, P4 and the first mandibular molar were extracted atraumatically from six Beagle dogs. The clean, dry teeth were ground immediately using the Smart Dentin Grinder. The tooth particles obtained were subsequently sieved through a special sorting filter into two compartments; the upper container isolating particles over 1200 μm, the lower container isolated particles over 300 μm. The crushed teeth were grafted into the post-extraction sockets at P3, P4 and M1 (test group) (larger and smaller post-extraction alveoli), while P2 sites were left unfilled and acted as a control group. Tissue healing and bone formation were evaluated by histological and histomorphometric analysis after 30 and 90 days. Results: At 30 days, test site bone formation was greater in the test group than the control group (p < 0.05); less immature bone was observed in the test group (25.71%) than the control group (55.98%). At 90 days, significant differences in bone formation were found with more in the test group than the control group. No significant differences were found in new bone formation when comparing the small and large alveoli post-extraction sites. Conclusions: Tooth particles extracted from dog’s teeth, grafted immediately after extractions can be considered a suitable biomaterial for socket preservation.

Sialolitiasis en glándula saliva menor: a propósito de un caso / Sialolithiasis of minor salivary gland: a case report

La sialolitiasis es la segunda patología más prevalente de las glándulas salivares, representando el 30% de la patología salival. La localización más frecuente es en la glándula submandibular, con alrededor del 80% de los casos de litiasis, mientras que la afectación de las glándulas salivares menores es de aproximadamente un 2%. La etiopatogenia de esta entidad sigue siendo un tema controvertido, sin embargo se atribuyen factores bioquímicos, infecciosos y mecánicos como los causantes de su formación. Una adecuada exploración física acompañada de la realización de pruebas complementarias de imagen, como la ecografía, resonancia magnética (RM) o tomografía computerizada (TC), serán fundamentales para el diagnóstico de la lesión. Se presenta el caso clínico de una paciente con diagnóstico de sialolitiasis de glándula salival menor labial tratada quirúrgicamente así como los resultados de la revisión científica bibliográfica hecha al respecto

Sialolithiasis is the second most frequent disease of the salivary glands, representing the 30% of whole salivary pathology. The most prevalent localization occurs in the submandibular gland, affected in 80% of cases of lithiasis, whereas minor salivary glands are concerned only in 2%. The etiology of this entity is still controversial, however different biochemical, infectious and mechanics factors have been attributed as the source of its formation. A correct physic examination along with supplementary images tests, as ultrasound, MRI or CT scan, will be essential for the right diagnosis. A case of a female diagnosed with sialolithiasis of minor salivary gland and surgically treated within a review of the literature is described