Cyclic fatigue resistance of Nickel-Titanium reciprocating instruments tested with an innovative kinematicsImpatto di una nuova cinematica sulla resistenza in fatica ciclica di strumenti reciprocanti

Aim

To evaluate cyclic fatigue resistance of different Nickel-Titanium instruments tested with an innovative reciprocating kinematics.

Guida alla scelta di un biomateriale per la preservazione alveolare: l’importanza dei fattori biologici di rimodellamento

Objectives

The study aims at outlining the major growth factors involved in socket healing dynamics as well as the biological events connected with bone substitute integration. Furthermore, the study in its clinical section investigates two different clinical models in order to examine the influence of different grafting materials on bone remodeling in the extraction socket.

Materials and methods

Dental text-books, oral-surgery handbooks and scientific databases have been investigated.

Results and conclusions

Thanks to their biocompatibility and osteoconductive properties, bone grafts, especially alloplasts have been successfully introduced in dental practice. In particular they faster the alveolar socket healing after tooth extraction and the maintenance of the edentulous ridge. On one side the remodeling dynamics after a tooth loss are well known, but on the other one, the influence of such grafting materials on the biochemical markers of bone remodeling is not fully understood. Immunohistochemistry seems a useful procedure to illustrate the effects of bone grafts on the remodeling pattern in vivo.     

Efficacia degli apparecchi funzionali associati alla trazione extraorale nel trattamento delle malocclusioni di II classe. Parte II

Objectives

The effectiveness of functional appliances (FJO) in association with extraoral traction (EOT) compared to functional appliances only in the skeletal correction of class II malocclusion in growing patients was evaluated.

Materials and methods

A literature review of the last 10 years was performed: the articles selection (RCT, CCT, meta-analysis) was based on explicit inclusion and exclusion criteria.

Results

We selected only three articles: the FJO + EOT treatment produced statistically significant skeletal effects in two of three samples for the mandibular growth, in one of three samples for the maxillary one.

Conclusions

The FJO + EOT treatment may produce slightly greater short-term skeletal effects than FJO treatment alone. More clinical trials are needed to prove this hypothesis.     

Analisi della morfologia radicolare e canalare di molari superiori ed inferiori in una popolazione Caucasica: studio in vivo alla CBCT

AimTo investigate the root and canal morphology of maxillary and mandibular permanent molar teeth in a Caucasian population by using Cone Beam Computed Tomography (CBCT).MethodsA total of 596 permanent molars were included. The number of roots, the number of canals per root and the root canal configurations according to the method of Vertucci were recorded.ResultsAlmost all of maxillary first molars (95.7%) had three separate roots; however, 40.3% of mesiobuccal roots had two canals (MB2). Of 157 maxillary second molars, 88.5% had three roots. Among the mesiobuccal roots, 15.1% had two canals. The majority of mandibular molars (100% of first molars, 89.4% of second molars) had two separate roots. Most distal roots had a simple type I configuration, whereas mesial roots had more complex canal systems, with more than one canal.ConclusionsCBCT is an efficient method of studying root canal systems.     

Trattamento di un caso complesso di trauma dentale

Objectives

The purpose of this article is to illustrate the management of major sport-related trauma in a young patient, which resulted in vertical fractures of alveolar processes 2.1 and 2.2.

Materials and methods

After obtaining a complete medical history and completing clinical and radiographic examinations, we reduced the fracture and immobilized the elements by splinting. The lacerated gingival flap was repositioned and sutured, and pulp vitality was assessed.

Results and conclusions

At the 18-month follow-up visit, the region involved in the trauma was fully intact. An analysis of this case and of the related literature confirms that early intervention is fundamental for the success of therapy.     

La patologia odontostomatologica associata alla malattia celiaca: revisione della letteratura

Objectives. The aim of this study is to review the association between celiac disease and several of the most common lesions of the oral cavity. Materials and methods. A careful literature search was conducted in the Medline and Embase databases using appropriate key words. Results. Enamel defects involving the deciduous and permanent teeth are the oral lesions most commonly associated with celiac disease. The review revealed only a weak association between celiac disease and recurrent aphthous stomatitis. Conclusions. Patients with systematic defects of the dental enamel should be screened for celiac disease, even in absence of gastrointestinal symptoms.     

Tipologie di cementi nel fissaggio di corone in zirconia-ceramica: revisione della letteratura

Objectives

The purpose of this article is to present a review of the literature about surface treatments and methods of cementation of zirconia.

Materials and methods

We undertook a review of international literature considering dental journals as well as international PubMed database.

Results and conclusions

The sandblasting is considered the best treatment for zirconia, which is followed by using auto-curing or dual-curing resin cements. The choice of the type of material used is in accordance with the clinical conditions.     

Analisi alla Cone Beam Computed Tomography della simmetria anatomica in molari superiori ed inferiori

AimTo analyze the symmetry in root canal configurations in the maxillary and mandibular permanent molar teeth of a Caucasian population using Cone Beam Computed Tomography (CBCT).ResultsOf 45 patients who had both maxillary first molars, 32 (71.1%) had perfect symmetry in the root and canal morphology of homonym teeth on the opposite side. As regards the maxillary second molars, the symmetry was observed in 43 patients (79.6%) of 54. Of 34 patients who had both mandibular first molars, 24 (70.6%) showed a perfect symmetry in the root and canal morphology of homonym teeth on the opposite side. As regards the mandibular second molars, the symmetry was observed in 47 patients (81%) of 58.ConclusionsCBCT is an exciting and clinically useful tool in studying root canal morphology and so the symmetry between homonym teeth.     

Malocclusioni di Classe II prima divisione: considerazioni sulla scelta di eseguire una o due fasi di trattamento

Objectives

To determine the appropriate timing for treatment of Class II Division 1 malocclusion.

Materials and methods

We conducted a review of the literature to analyze the controversy surrounding the use single-phase versus two-phase orthodontic treatment for this type of malocclusion.

Results

The evidence shows that early orthodontic treatment is effective in specific clinical situations, but in many other cases, later single-phase treatment is more appropriate.

Conclusions

The practicing orthodontist should tailor treatment timing to the specific clinical situation.     

Un approccio estetico alla gestione del paziente ortodontico: il sistema Clearstep

Objectives

Clearstep represents a revolutionary orthodontic treatment solution based on clear, medical grade polyethylene glycol positioners.

Materials and methods

The gentle forces delivered by each positioner produce an incremental tooth movement until the desired result is achieved. Each positioner is worn for at least 20 hours a day for 15 days.

Results

Either alone or in combination with traditional orthodontic techniques, Clearstep can treat even the most severe dental malocclusions. The Clearstep treatment offers many advantages to both clinicians and patients.

Conclusion

The Clearstep technique is an extremely comfortable and aesthetical alternative treatment option.     

Trattamento di un caso con discrepanza dell’indice di Bolton

Objectives

To show the treatment of Bolton Index discrepancies by the Invisalign System.

Case Report

A 20 year-old female patient came to our attention complaining of poor aesthetics and spacing among her upper teeth. The patient asked for an Invisalign treatment for the upper arch only. A request more and more frequent in our clinical practice due to the excellent comfort and aesthetics of these devices.

Discussion and Conclusion

At the end of the treatment, a good alignment of both upper and lower teeth was obtained together with the elimination of the spacing among upper teeth. The Invisalign system also proved to be particularly suitable for this type of problem from a clinical and a biomechanical point of view.     

Analisi dei metodi di mantenimento dei margini di chiusura nelle protesi senza struttura in metallo

Objectives

We used scanning electron microscopy (SEM) to comparatively evaluate damage to the finish line of metal-free dental crowns produced by dental hygiene maintenance procedures performed with different types of manual and mechanical instruments.

Materials and methods

Twenty-one extracted teeth (all in good condition) with chamfered margins were divided into seven identical groups. The three teeth in each group were fitted with metal-free crowns (1 zirconium oxide, 1 aluminum oxide, and 1 ceramic) and treated with the following: steel-tipped ultrasound (US) device (group 1); polyether ether ketone (Peek)-tipped US device (group 2; steel scaler (group 3); polycarbonate curette (group 4); red ring handpiece with soft rubber tip (group 5); prophylaxis paste applied with cups on a contra-angle handpiece (group 6); soft glycine-powder air polishing (group 7). All instruments were used by the same operator under standard conditions. After the completion of decontamination protocols, the crowns were examined with SEM. The three teeth of group 1 were also subjected to SEM before the treatment (as an untreated control group).

Results

Compared with their respective untreated controls, the treated crowns all displayed surface modifications. Those treated with the steel-tipped US device or the steel scaler displayed sulci and scratches on the surface of the area inspected. Only light scratches were seen on the crowns treated with the Peek-tipped US device. In the groups treated with devices designed to remove plaque only, no appreciable changes were observed. In group 7 (treated with soft glycine air polishing), the aluminum and ceramic crowns displayed tiny “craters” a few microns in diameter (magnification 1000×), but no significant changes were observed in the zirconium crown from this group.

Conclusions

The results of this study suggest that deplaquing alone may be the method of choice in this setting. Of the methods tested, it was the only one that did not produce morphological or structural damage to the metal-free crowns. However, if tartar has to be removed from the finish line of the crown, the only solution is the Peek-tipped US device, which proved to be the most effective and least aggressive of the methods tested.     

Valutazione della capacità di taglio di tre punte diamantate a diversa granulometria nella preparazione protesica di elementi dentari

Objectives

The purpose of this study is twofold: first, to determine the most effective diamond grain size in removing dental hard tissues, among the three tested abrasive points used in prosthetic crown preparation, and secondly to assess the relationship between the cutting capacity of the three points and the surface crystal density of each abrasive diamond point.

Materials and Methods

The cutting capacity of three different diamond points with three different grain sizes – respectively 100 μm (Komet 878), 120 μm (Komet 6878), 180 μm (Komet 5878) – was evaluated in this study. Such drills were inserted into the head of an electric highspeed high-torque handpiece connected to a mechanical arm to better standardize the working and dynamic conditions. The cutting capacity tests were conducted on samples of macor (CS Ltd, Newport, UK), glass ionomer material, with characteristics of hardness and elasticity similar to the natural tooth tissues. The three tested diamond points were also examined under a polarized light optical microscope with magnification of 10X and processed by an image analysis software (Scientific Image-Analysis, ImageJ, National Institutes of Health, USA) before use, in order to evaluate the crystal density modification in the three different grain sizes.

Results

The medium grain size abrasive point (100 μm) showed the best cutting ability, namely 0.217 mm/s, expressed in millimeters of diamond point sinking into the macor synthetic material, per unit time. The second best result was achieved by the coarse grain size diamond point (120 μm) that amounts to 0.181 mm/s; the worst value was obtained with the use of extra coarse grain size point (180 μm) that amounts to 0.145 mm/s. The cutting capacity of the three different points diminished proportionally with the number of performed cuts. The crystal density of the three abrasive points, analyzed under microscope before their use, was substantially the same in every cutting surface. Indeed, the medium grain size (100 μm) shows a density that amounts to 85.1%, likewise the coarse and the extra coarse grain size (120–180 μm) exhibit density values amounting respectively to 83.4% and 85.3%.

Discussion

This in vitro study indicates the medium size grain (100 μm) as the most effective in dental tissues cutting capacity. The use of the medium grain size (instead of coarser size) is a favorable condition in prosthetic preparations because it allows to keep the initial dental surface preparation roughness at contained values and makes it easier to smooth finish dentin surfaces. Crystal density alone cannot justify the different cutting capacity of the three abrasive tested points since variations are not significant. Therefore the cutting ability of abrasive points should be essentially linked to the characteristics of the single grains (grain size) rather than to their disposition or density.

Conclusions

This in vitro trial has produced results that disagree with the data obtained by the few previous studies of comparable methodological approach and interest topic. Indeed, in the literature some trials demonstrate no relationship between diamond grain size and cutting ability of rotating instruments. Other studies show a reduced grinding power expressed by the medium grain size diamond points compared to coarser abrasive burs, especially during prolonged or repeated use. The studies disagreement in this field should stimulate further trials preferably by means of clinical rather than in vitro procedures.     

Radiotrasparenza dell’angolo mandibolare. Due casi di lacuna di Stafne

Objectives

To describe two Stafne bone cavity cases, focusing on instrumental investigations besides pathogenesis, in order to reach correct differential diagnosis and therapy.

Materials and methods

In the two presented cases, having acknowledged negative pathological anamnesis and characteristics of lesion, the Authors agreed in formulating a presumptive diagnosis of Stafne bone cavity. Stafne bone cavity is a rare, benign, asymptomatic, hardly noticeable lesion in conducting clinical examination. Pathogenesis is not completely evident yet, and in radiographic examination it displays as a unilocular radio-transparent and well-defined lesion, localized in between the bone adjacent to the first molar and the mandibular angle, underneath the inferior alveolar canal. Diagnosis gets simple as bone cavity shows up in the more frequent and common form, whereas in case of doubt it is important an ulterior diagnostic deepening in order to confirm the presumptive diagnosis.

Results and conclusions

Stafne bone cavity does not require any treament, periodic radiographic follow-up is suggested in order to monitor any modifcation or change in the aspect of lesion, and to avoid eventual degenerations.     

Rialzo di seno transcrestale e chirurgia guidata: proposta di nuova tecnica

ObjectivesThe aim of this study is to illustrate an innovative crestal sinus lift technique during a guided implant surgery with a set of drills designed to obtain the opening of sinus floor and the membrane lift.Materials and methodsA set of drills has been developed by the change in length and size of those of Cosci for crestal sinus lift to be used with stereolythographic template in upper posterior sites with 4–9 mm of residual bone height.ResultsTo illustrate the potentiality of this technique it's illustrated a paradigmatic clinical case with 4 mm of residual bone height during which it was possible to insert a 7 mm short implant with a good initial stability lifting the membrane after the opening of the internal cortical bone and achieving new bone formation without substitution materials.ConclusionsThe limited number of already done clinical cases does not allow to draw correct conclusions on the potential of this technique even though short-term results seem quite promising.