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The present study was conducted to evaluate human pain perception at different phases of dental surgery using a computer controlled device, the Single Tooth Anesthesia System (STA System), versus the traditional syringe technique. One hundred healthy patients participated in this single-blind split-mouth design study. Individuals provided pain ratings at needle insertion, delivery of anesthetic solution and tooth extraction via a numeric visual rating scale or NVRS. The anterior middle superior alveolar, or AMSA, injection was compared with traditional syringe injections in maxillary quadrants. NVRS scores for AMSA were significantly lower for the STA System when compared to traditional syringe technique at needle insertion, delivery of anesthetic solution (p less than 0.0001) and also during tooth extractions (p=0.0002). A higher percentage of patients (23 percent) required a second injection after the traditional syringe technique. Subjects reported having less clinical pain with AMSA injection at every step of the dental surgery. The STA System combines an anesthetic pathway and controlled flow rate resulting in virtually imperceptible needle insertion and injection, and a rapid onset of profound anesthesia. NVRS scoring system facilitated patient comprehension in assessing pain value and intensity experienced. The two anesthetic delivery techniques were therapeutically equivalent for maxillary injections but AMSA/computer controlled protocol significantly minimizes subjective pain perception at needle insertion, anesthetic delivery and during tooth extraction.

The recently introduced ultrasonic osteotome procedure is an alternative to conventional rotatory burs. The aim of this study was to establish the differences between two ultrasonic osteotomes and conventional rotatory burs, in order to perform micromorphological and histological analyses of osteotomized bone surfaces. Bony samples were taken from adult bovine ribs including both the cortical and marrow bone. Soft tissues have been removed and the bone pieces were divided into four groups, to test four devices: a conventional osteotomy round bur, a Lindeman bur and piezoelectric osteotomes ES007 and the T-Black. Each device performed cuts that were examined via scanning electron microscope (SEM) and light microscopy (LM) to check respectively cut precision and bone architecture all along the defect borders. SEM analysis of specimens showed that burs created defects of greater width and with irregular edges while those produced by ultrasonic osteotomes were narrow and had mostly smooth cutting surfaces. The edges of incisions made by drills were full of bone fragments while less bone chips were observed on piezoincision’s ones. Dimensions of fragments were wider if cuts were made by burs too. LM analysis of samples showed focally, delicate bony trabecules crushed and pressed into the bone marrow in cutting made by burs. Samples cut by ultrasonic devices showed small or no smear layer and only partial or no crushed trabecules. Osteocytes seemed to be intact all along the cutting surface in all samples observed. In the present study, according to literature, ultrasonic surgery validity is confirmed. As a matter of fact, the greater the number of bone chips products, the greater the magnitude of the inflammatory process induced, as well as the possibility of a greater bone loss and delay in wound healing near the osteotomized area.

The aim of this work is to examine the behaviour of laser treated gutta-percha (a–b) after heating, to test the validity of a new obturation technique. Samples of laser- and no laser- treated gutta-percha have been examined by the thermal/thermogravimetric analysis and compared. All samples have been submitted to four runs of heating from the temperature of 25–130 C, followed by spontaneous cooling. It was found that some samples have shown the typical behaviour of the alpha-gutta-percha; others have shown characteristics similar to the conventional beta-gutta-percha. The laser treated gutta-percha has shown a significant mass loss after the first run of heating, while the mass tends to stabilize after the third run. It has been demonstrated that the 980 nm diode laser used with cited parameters does not alters thermal behaviour of gutta-percha cones.

The roughness and the purity of implant surfaces are key points in the osteointegration process. The surfaces obtained by classic methods present irregular non-reproducible patterns and furthermore contaminate the implant surface with materials other than titanium which interfere with the process of osteointegration. The aim of the present study is to evaluate, by SEM/EDX and XPS analyses, the surface microstructure and the purity of new laser-treated implant surfaces. The laser treatment of the surface allows to set parameters to determine the roughness in order to obtain a regular and repeatable surface. Furthermore, there being no contact between the implant and the machine, there is no surface contamination with elements other than titanium. In this study we used a diode-pumped solid state laser (DPSS) with Nd:YAG source operating in Q-Switching mode on titanium samples. The resulting samples were analysed by SEM/EDX and XPS to evaluate morphology and purity of the surface. The results show surfaces with very regular roughness and a total absence of contamination.

The main therapeutic approaches for inflammatory periodontal diseases include the mechanical treatment of root surfaces. Multi-center clinical trials have demonstrated that the adjunctive use of a chlorhexidine (CHX) chip is effective in improving clinical results compared to scaling and root planing (SRP) alone. However, some recent studies failed to confirm these clinical results, nor have any data been reported regarding the capability of the CHX chip in affecting the activity of alkaline phosphatase (ALP) in the gingival crevicular fluid (GCF). This enzyme has been related to a condition of destructive activity of periodontitis. The aim of this study is to provide further data on the clinical and biochemical effects of CHX chips when used as an adjunct to SRP. Eighty-two systemically healthy patients, aged 31-63, with moderate and advanced periodontitis were recruited from the departments of Periodontology of the University of Chieti. In each patient 2 experimental sites, located in two symmetric quadrants, were chosen with a probing depth of > or = 5 mm and bleeding on probing. The 2 sites were selected randomly at the split-mouth level; control sites received SRP alone, and test sites SRP plus 1 CHX chip. Clinical indices, including probing depth (PPD), clinical attachment level (CAL), bleeding on probing (BOP), and the ALP activity in GCF were evaluated at baseline and after 6 months. Alkaline phosphatase activity was assayed spectrophotometrically. The PPD and CAL were significantly lower at 6 months as compared to the baseline scores in both treatments (p less than 0.01). The PPD reduction was 2.7 mm in the CHX+SRP group and 1.9 mm in the SRP alone group. The CHX+SRP group showed a significantly greater gain of clinical attachment (mean: 1.4 mm) in comparison with the SRP group (mean: 0.9; p less than 0.05). No differences were observed in the decrease of the percent of BOP-positive sites between the experimental groups. Conversely, the CHX+SRP group underwent a significantly greater decrease (p less than 0.01) of the GCF-ALP activity 6 months after treatment in comparison with the SRP alone group. The adjunctive use of the CHX chip resulted in a significant improvement of pocket reduction and clinical attachment gain as compared with SRP alone. These results were concomitant with a significantly greater reduction of the GCF-ALP activity levels.

The aim of this study is to test the response of bone during cutting actions in dental procedures by sampling alkaline phosphatase (ALP) as a biological reference marker. ALP is found abundantly in bone tissue. In the first series of experiments a temporal-minimum quantity of ALP enzyme response was recorded, the observed period was 40 minutes. The ALP samples treated with piezoelectric surgery showed a rapid increase, with peak at 30 min, and then declined rapidly within the next 10 minutes. A second experiment was performed to evaluate 4 cutting instruments: drill bits high speed turbine (T1); drill bits contra-angle (T2) Piezoelectric insertions (T3), and manual instruments (controls). This second experiment was to evaluate the ALP activity at 30 min. The T1 samples produced the highest results (3,66499 +- 0,51394); control groups had a lower response (0,72793 +- 0,22353), while the T2 group produced statistically significant higher results (2,77793 +- 0,40553) than T3 (1,16608 +- 0,32676). The different values obtained for ALP in these two experiments for a short period of time (30 min) cannot be interpreted as a response of bone tissue regeneration subjected to surgical trauma. The MINIMUM trauma caused by the surgical piezoelectric instruments, in respect to conventional surgical instruments is clearly evident from the phosphatase inflammatory activity.