Experimental analysis about the evaluation of tungsten carbide-bur, piezoelectric and laser osteotomies.

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.

Reduction of precocious peri-implant resorption cone.

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.

Evaluation of quality of life in patients with total or partial edentulism treated with computer-assisted implantology.

AIM: The study deals with a preliminary analysis that compares quality of life of a randomized sample of patients with total or partial edentulism rehabilitated through conventional implantology or computer-assisted implantology. METHODS: The first group was treated with conventional implantology, while the second group was treated with NobelGuide™ computer-assisted implantology. every patient has filled up a questionnaire about quality of life in presurgical period (sf-361), in postsurgical period (sf-361; tiq2) and about the gratification after prosthetic treatment. the questionnaire has evaluated physical, general and psycho-emotive health parameter. RESULTS: SF-36 has demonstrated an improvement in quality of life after computer-assisted surgery. tiq has revealed that patients symptoms in post-surgical week were inferior in quality and in quantity in NobelGuide™ technique. gratification questionnaire has demonstrated that quality of life improvement matches patient full satisfaction after the treatment. CONCLUSIONS: NobelGuide™ protocol improves physical health after implantology with positive reflections on psycho-emotive health. furthermore prefabricated temporary prostheses reduces treatment time and patient discomfort.

Lingual frenectomy: a comparison between the conventional surgical and laser procedure.

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.

NobelGuide™ influence in the perception of postoperative pain.

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.

Aneurysmal bone cyst of the nasal bone: case report.

The aneurysmal bone cyst (ABC) is a solitary, expansile, non-neoplastic bone lesion, described as a distinct clinicopathological entity by Jaffe and Lichtenstein. We report a case of an ABC arising from the nasal bone in a adult male patient treated with complete surgical excision.

Tongue flap to treat a severe case of Miescher's cheilitis granulomatosa.

Miescher's cheilitis granulomatosa is the monosymptomatic form of Melkersson-Rosenthal Syndrome. Severe macrocheilitis often causes a functional and esthetical impairment of the lip. Conservative treatment represents the first option to face this rare disease. Unfortunately, medical treatment is often ineffective without any significant result as far as swelling and disfigurement are concerned. Reductive cheiloplasty is indicated in all those patients who have failed to respond to medical treatment. Excision of excess tissue may be obtained by means of several surgical techniques. We report a case of a 55-year-old man affected by severe granulomatous cheilitis refractory to any medical treatment and then treated with the use of tongue flap for the reconstruction of the excised lower lip.

How to improve retromandibular transmasseteric anteroparotid approach for mandibular condylar fractures: our clinical experience.

Fractures of the mandibular condyle are common and account for 25-35% of all mandibular fractures reported in the literature. Even with the development of a consensus on the preference for open reduction and internal fixation of these fractures, the clinician is still faced with a dilemma concerning the optimal approach to the ramus-condyle unit. Limited access and injury to the facial nerve are the most common problems. The most commonly used extraoral approaches are the submandibular, retromandibular and preauricular methods. In this study, we propose a modified cosmetic preauricular incision with a short end in the neck, to improve the transmasseteric anteroparotid (TMAP) approach previously described by Wilson et al. in 2005. We retrospectively analysed 13 patients treated in our department for mandibular condylar fractures. Post-operative complications, occlusal status, interincisal opening and joint tenderness were evaluated at 3 months after surgery. The wider skin incision described here provides a convenient approach for open reduction and rigid internal fixation, and good results were obtained. The follow-up ranged from 6 to 40 months.

Early c-Jun N-terminal kinase-dependent phosphorylation of activating transcription factor-2 is associated with degeneration of retinal ganglion cells.

Neuron death due to deprivation of target-derived neurotrophic factors depends on protein synthesis regulated by transcription factor activity. We investigated the content and phosphorylation of activating transcription factor 2 (ATF-2) in axon-damaged retinal ganglion cells of neonatal rats. In the retina of neonatal rats, the ATF-2 protein is predominantly located in the nucleus of the ganglion cells. A gradual loss of the immunoreactivity for ATF-2 occurred after explantation. ATF-2 is phosphorylated early after explantation, with a peak within 3 hours, preceding the peak of cell death that occurs at 18 hours. Both the phosphorylation of ATF-2 and ganglion cell death were blocked by treatment with an inhibitor of c-Jun N-terminal kinase (JNK), whereas an inhibitor of p38 reduced only slightly the rate of ganglion cell death with no effect upon phosphorylation of ATF-2. Inhibitors of phosphatidyl inositol 3 kinase (PI-3K), protein kinase C (PKC) or extracellular regulated kinase (ERK) had no effect. Finally, the inhibitor of JNK blocked the upregulation of both c-Jun and Hrk in the GCL after retinal explantation. The data show that phosphorylation of ATF-2 by JNK is associated with retinal ganglion cell death after axon damage.

Application of multiplex single nucleotide primer extension (mSNuPE) to the identification of bacteria: the Burkholderia cepacia complex case.

Burkholderia cepacia complex (BCC) is characterized by a complex taxonomy constituted by seventeen closely related species of both biotechnological and clinical importance. Several molecular methods have been developed to accurately identify BCC species but simpler and effective strategies for BCC classification are still needed. A single nucleotide primer extension (SNuPE) assay using gyrB as a target gene was developed to identify bacteria belonging to the B. cepacia (BCC) complex. This technique allows the successful detection and distinction of single nucleotide polymorphisms (SNPs) and is effectively applied in routine medical diagnosis since it permits to analyze routinely many samples in a few times. Seven SNuPE primers were designed analyzing the conserved regions of the BCC gyrB sequences currently available in databases. The specificity of the assay was evaluated using reference strains of some BCC species. Data obtained enabled to discriminate bacteria belonging to the species B. multivorans, B. cenocepacia (including bacteria belonging to recA lineages III-A, III-C, and III-D), B. vietnamiensis, B. dolosa, B. ambifaria, B. anthina and B. pyrrocinia. Conversely, identification failed for B. cepacia, B. cenocepacia III-B and B. stabilis. This study demonstrates the efficacy of SNuPE technique for the identification of bacteria characterized by a complex taxonomical organization as BCC bacteria.