Stomatological approach to Sjögren's syndrome: diagnosis, management and therapeutical timing.

Sjögren's syndrome is a chronic multisystem autoimmune disease characterized by the exocrine glands inflammation, with subsequent hypofunction. More frequently lachrymal and salivary glands are interested with subsequent xerophthalmia and xerostomia. Sjögren's syndrome can be present in an idiopathic type or in association with other autoimmune diseases as rheumatoid arthritis, systemic lupus erythematosus, schlerodermia, etc. It interests mainly the women (with a ratio F:M=9:1) with an age between 40 and 60 years old. The disease prevalence varies from 0.4% to 4.8%. The glandular lesions determine in the time a volume reduction and a secretum quality alteration. The most frequent oral manifestations are xerostomia, that allows the establishment of caries, gingivitises, periodontal disease and oral candidiasis. The aim of this work was to perform a thorough review of the literature on Sjögren's syndrome, illustrating the most internationally accredited diagnostic criteria, the patient's management and therapeutical approach in the odontostomatological discipline. The Authors conclude that it doesn't exist a resolutive treatment of the disease. The therapy is only palliative, and is turned to the treatment of xerostomia and xerophthalmia, through systemic and aspecific sialogogues drugs. From the odontostomatological point of view, particularly useful results the domiciliary and professional oral hygiene to contrast the xerostomia effect on the oral structures.

Shaping outcomes using two Ni-Ti rotary instruments in simulated canals.

AIM: The aim of this study was to compare the shaping ability of Mtwo and ProTaper instruments in simulated curved root canals in resin blocks. METHODS: The study was carried out using 40 simulated canals in resin blocks, all of which had the same canal diameter (0.70 mm>D>0.20 mm), length (16 mm), and angle of curvature (40 degrees). These 40 canals were divided into 2 groups of 20 specimens. Both before and after instrumentation, all the resin specimens were photographed, and all the canals examined were measured at 4 different points of reference. Using a computer image analysis program, the photographs of corresponding sections were superimposed on one another. In this way we sought to evaluate the shaping ability of these 2 systems in relation to specific portions of the root canal, also with regard to maintenance of original canal curvature. The results were analysed using Student's t-test. RESULTS: Both rotary systems were found to respect the original root canal curvature, particularly in the areas most at risk of modification, namely the outer aspect of the curve in the apical third of the canal. The Mtwo instruments caused less transportation of the apex than the ProTaper instruments, but this difference was not statistically significant (P>0.05). CONCLUSION: According to the results of this study, both these instruments respected the original canal curvature, particularly in the areas at most risk of modification, and they also showed good shaping ability in curved canals, with minimum transportation of the apex.

Mechanical evaluation of new injection needles for dental anesthesia.

AIM: In this study Authors want to evaluate the static and dynamic flexural behaviour of innovative injection needles for dental anaesthesia comparing to the traditional needles. METHODS: Four kinds of innovative injection needles (Carpule Free Flow-Heraeus Kulzer), different for length and external diameter, have been evaluated in comparison with the traditional ones (Carpule-Heraeus Kulzer), dimensions being equal except for the internal diameter. Static stiffness tests (10 for each kind of needles, resulting in a totality of 80 tests) and fatigue bending test (10 for each kind of needles, each tested at 3 different bending angles, resulting in a totality of 240 tests) have been conducted following the ISO 9626 norms. The final comparison among the obtained data have been conducted using a one way statistical analysis of variance (ANOVA). RESULTS: After stiffness tests the Carpule Free Flow injection needles and the traditional ones showed the same static behaviour, resulting in statistical comparable values of mean deflection at the maximum load allowed by ISO norms tests, whereas the 0.4 mm external diameter showed a statistically significant difference because the Carpule Free Flow needles achieved lower deflection values. After dynamic bending tests at 20 degrees both needle types showed the same behaviour, whereas at 30 degrees bending the Carpule Free Flow injection needles showed a higher number of breaks comparing to normal type, up to a maximum value of breaks (10 out of 10) for the 0.4 mm external diameter needles. After 50 degrees fatigue bending tests the Carpule Free Flow needles came to the break point after lower number of cycles than the Carpule needles. CONCLUSION: This study pointed out that, among anaesthesia injection needles, the Carpule Free Flow needles not only showed better clinical characteristics but also a mechanical behaviour, both static and dynamic, statistically similar to traditional ones, according to international standards. After fatigue bending higher than 20 degrees, exclusively made in this research in order to simulate critical or extreme conditions, all analysed Carpule Free Flow needles have been broken after a lower number of cycles. It is concluded that it is recommended not to repeatedly bend this kind of needles at more than 90 degrees. At the end of this study it may be suggested that this kind of needles cannot be repeatedly bended at angles more than 90 degrees.

Endodontic treatment of a fused tooth. Report of a case.

Dental fusion, a rare developmental anomaly present in 0.2% of the general population, consists of the union of two teeth originating from two different tooth germs. The irregular coronal morphology and the complex endodontic anatomy, characterized by the partial or total union of the pulp chambers, together with the peculiarity of the root canal systems, make diagnosis, therapy and rehabilitation difficult. The authors describe the endodontic treatment of a permanent lower second molar fused with a third molar and having four root canals.

Bond strength to deep coronal dentin: effect of bonding strategies.

AIM: The aim of this study was to evaluate bond strength at the composite-adhesive-deep dentin interface following pre-treatment with sodium hypochlorite using 4 different types of enamel-dentin adhesive and a composite for the core. METHODS: From 60 healthy human molars, cylindrical samples (3 mm high) were obtained using a special slow-speed saw. Cavities with 2-5-mm diameters were made in all the samples. Samples were assigned to 8 groups, 4 groups were designated as experimental groups and were irrigated with NaOCl and the other 4 groups designated as control groups were irrigated with distilled water. Adhesive systems were applied to the samples and then restored using a core build-up composite. Samples were subjected to shear stress test using an electronic dynamometer. RESULTS: The data were analyzed using one-way ANOVA and the Tukey test (P<0.05). The results, in terms of bond strength, demonstrate that the two-step self-etch adhesive systems generate a stronger bond than the other systems considered in the study (P<0.05). The results also show that pre-treatment with hypochlorite does not seem to influence the bond strength of self-etch adhesive systems. CONCLUSIONS: This in vitro study demonstrates that there exist differences in bond strength between self-etch and etch & rinse adhesive systems on deep dentin pretreated with sodium hypochlorite to simulate endodontic treatment.

Complications in implant surgery by Summer's technique: benign paroxysmal positional vertigo (BPPV).

The aim of this study is to show the correlation between implant surgery using an osteotomic technique and benign paroxysmal positional vertigo (BPPV). The case of a 55-year-old patient submitted to oral implant surgery in the 2.3 area is described. The ridge was thin in this particular location and therefore the maxillary expansion technique according to Summer was preferred. After removing the sutures, the patient suffered from vertigo and was in a confusional state. The patient was therefore placed in the Tredelenburg's position and a few minutes later he felt better. However, the symptomatology that seemed disappeared was present again the following day. A careful check-up showed the presence of BPPV, treated as described in this paper.

[Treatment of curved canals: from stainless steel to nickel titanium]. / Trattamento dei canali curvi: dall'acciaio inossidabile al nichel-titanio.

Endodontic treatment of curved canals is always more difficult than straight canals, especially for the apical zone preparation: root canals may present several curvatures in different space directions. From an anatomical point of view root canals with accentuated curvatures are a very frequent event (more than we might think); radiological exams, in fact, give us only a 2D image, and we can observe mesial or distal curvatures but not those in the oral or buccal direction. However, all root canals have curvatures of some degrees; even those that appear straight. Because of this, endodontitis have made many attempts to overcome these problems and manage to have a good preparation in curve canal. The authors analyse all endodontic techniques (step back, step down, crown down, balanced forces) codified in the course of the years, to prepare curved canals; they both in shape or in materials. It's fundamental for the endodontist to have a specific technique to treat curved canals to allow a good, wide preparation; in this way it's possible to make a better and tridimensional filling of the endodontic space above all in the tipical zone.

[Mechanical properties of nickel-titanium files following multiple heat sterilizations]. / Effetto delle procedure di sterilizzazione sulle proprietà meccaniche di strumenti endodontici in nickel-titanio.

AIM: The effect of cycles of sterilization procedures on nickel-titanium (NiTi) endodontic instruments is a serious concern for practitioners. There is no agreement in the literature whether these procedures could adversely affect the mechanical properties of endodontic files, and, consequently, increase the risk of intracanal failure. The purpose of this study was to evaluate the mechanichal resistance of Hero (MicroMega, Besancon, France) instruments, before and after sterilization procedures. METHODS: Thirty 02, 04, 06 tapered Hero size 30 new instruments were chosen and divided into 3 groups. Group A (control) were tested according to ANSI/ADA Spec.no 28 for torsional resistance, angle of torque and angle at breakage (45 inverted exclamation mark ). Group B files were first sterilized with chemiclave for 10 cycles of 20 minutes at 124 inverted exclamation mark C and then tested as described above. Group C files were first sterilized with glass beads for 10 cycles of 20 sec. at 250 inverted exclamation mark C and then tested as described above. Data were collected and statistically analyzed (t-paired test). Differences among the 3 groups were statistically not significant for both tests. RESULTS: All data were well within Spec.no 28 standard values. CONCLUSION: From the results of the present study, we may conclude that repeated sterilization procedures do not adversely affect the mechanichal resistance of Hero files.

Mandibular first and second molar. The variability of roots and root canal system.

The root and canal anatomy of mandibular first and second molars has normally recurring features, as well as a great number of atypias. Normally mandibular first and second molars have two roots, one is mesial and the other is distal, and at least three main canals. The roots of the second molar can change from one to three, the first molar can have also four roots; the canals can change from three to even six. The conventional root canal anatomy indicates the location of the initial access. The knowledge of both the normal and abnormal anatomy of molars shows the parameters under which root canal therapy is to be executed and can directly modify the probability of success. This is the reason why endodontists must be familiar with all abnormalities as well as their percentage. We present a review of the modern literature about the event of aberrances with references to the number and morphology in mandibular first and second molar root and root canals.

Some unusual clinical cases on root anatomy of permanent maxillary molars.

Three case reports are presented concerning permanent maxillary molars with fusion of two buccal roots. The morphology is peculiar because it is characterized by the mesiobuccal canal merging into the distobuccal canal in their apical one-third. A thorough review of the literature failed to reveal any previously reported description of permanent maxillary molars with this arrangement of canals, with the exception of a recently reported epidemiological study.

[Salivary HIV antibodies. Review of current data and future prospectives]. / Gli anticorpi anti-HIV salivari. Rassegna delle più recenti acquisizioni e prospettive per il futuro.

Medical researchers, especially those involved in AIDS studies, have shown increasing interest in the salivary diagnosis in the recent years. Saliva sample collection is simple, quick, non traumatic and it can be done at low cost. Moreover saliva specimens can be collected without significant infection risks for both patients and operators. The presence of HIV-antibodies in the saliva, along with the above mentioned reasons, makes saliva sample a promising means of testing for HIV antibodies. The attached report summarizes the results of studies carried out by various researchers to assess the reliability of several test methods for HIV-antibodies.

[The role of oxytalan fibers in the stomatognathic system. A bibliographic review]. / Il ruolo svolto dalle fibre ossitalaniche nell'apparato stomatognatico. Rassegna bibliografica.

The authors review the oxytalan fibers, that belong to the elastic system fibers of the connective tissue. They are observed in many structures of the stomatognathic system, particularly in the periodontal ligament and TMJ disc.

[Immunohistochemical demonstration of neuropeptide Y in the normal human thymus and in thymoma]. / Dimostrazione immunoistochimica del neuropeptide Y nel timo umano normale e nel timoma.

The distribution of neuropeptide Y-like immunoreactivity in normal thymic parenchyma and in thymoma was evaluated in order to characterize the typical aspects of the thymic peptidergic pattern of innervation in normal and pathological conditions. The possible role of neuropeptide Y in neuromodulation of the immunological response is discussed.