Aneurismal bone cyst: a conservative surgical technique. A case report treated with a small access osteotomy.

BACKGROUND: Aneurismal bone cysts (ABCs) are benign, non-neoplastic, expansive, and locally destructive lesions that may occur rarely. They are well defined and usually occur in the long bones, pelvis and vertebrae. According to the 2005 World Health Organization (WHO) histological classification of odontogenic tumours, ABC is classified as a bone-related lesion as ossyfing fibroma, fibrous dysplasia, osseous dysplasia, central giant cell lesion (granuloma-CGCL), cherubism and simple bone cyst (SBC). ABCs, as CGCLs and SBCs may arise as a consequence of an earlier trauma causing an overflow of blood into the bone, though a number of pathogenic theories have been put forward. The aim of this study is to present an unusual case of aneurismal bone cyst and to compare the different possibilities of surgical treatment after review of the literature. CASE REPORT: ABC was localised in the posterior right region of the mandible in an 11-year-old boy, and removed by a surgical procedure involving a small access osteotomy of the mandibular ramus with removal of the cortical bone in order to enucleate the whole lesion, the wisdom tooth and to preserve the healthy bone.

Pycnodysostosis: review and case report.

AIM: Aim of the present study was to present a case report of a patient suffering from pycnodysostosis and assess how it may manifest and affect the dental/ orthodontic treatment. METHODS: An 11-year-old patient who was diagnosed with pycnodysostosis at the age of 18 months, attended the orthodontics department requiring treatment for extensive carious lesions, periodontal disease and severe crowding. RESULTS: After an accurate radiographic, clinical and orthodontic assessment of the patient taking into consideration the severity of the condition and the patient's necessities, we have formulated a treatment plan, which was accepted by both the patient and parents. We took into consideration the risks and benefits of the options available and the requests of the patient. CONCLUSION: We have decided to opt for the extraction of teeth to relieve the crowding as this was impeding good oral hygiene and hence increasing the risk of caries and periodontal disease. Such patients must be placed under an oral hygiene prevention scheme, a treatment plan must be accurately designed and the patient must be constantly motivated.

Large buccal bifurcation cyst in a child: a case report and literature review.

BACKGROUND: WHO defines the mandibular buccal bifurcation cyst as a cyst occurring near the cervical margin of the lateral aspect of a root as a consequence of inflammatory process in a periodontal pocket. The pathogenesis of these cysts is still debated, but they are most likely originated from reduced enamel epithelium or from inflammatory proliferation of epithelial cell rests of Malassez that come from the superficial mucosa of a tooth in eruption. The aim of this article was to describe a case of large buccal bifurcation cyst of a permanent mandibular first molar. CASE REPORT: A 6-year-old boy was referred to Department of Oral Riabilitation of the Istituto Stomatologico Italiano, University of Milan, Italy, with the complaint of hard swelling over the buccal gingiva and a deep probing depth located on the buccal aspect. Radiograph revealed a well-defined semilunar-shaped radiolucency, marked by a fine radiopaque line on the buccal aspect of the partially-erupted lower right first molar and it was large enough to include a small part of the crown of the second right molar. As reported in the literature the treatment of choice is enucleation and curettage of the lesion without extraction of the vital involved tooth. This procedure has shown excellent results in both the short- and long-term. The definitive diagnosis of paradental cysts can be assessed by histopathologic analysis.

Digital device in postextraction implantology: a clinical case presentation.

Aim. The aim of this work is to describe a case of immediate implant placement after extraction of the upper right first premolar, with the use of CAD/CAM technology, which allows an early digital impression of the implant site with an intraoral scanner (MHT 3D Progress, Verona, Italy). Case Report. A 46-year-old female was referred with a disorder caused by continuous debonding of the prosthetic crown on the upper right first premolar. Clinically, there were no signs, and the evaluation of the periapical radiograph showed a fracture of the root, with a mesial well-defined lesion of the hard tissue of the upper right first premolar, as the radiolucent area affected the root surface of the tooth. It was decided, in accordance with the patient, that the tooth would be extracted and the implant (Primer, Edierre implant system, Genoa, Italy) with diameter of 4.2 mm and length of 13 mm would be inserted. After the insertion of the implant, it was screwed to the scan abutment, and a scan was taken using an intraoral scanner (MHT 3D Progress, Verona, Italy). The scanned images were processed with CAD/CAM software (Exocad DentalCAD, Darmstadt, Germany) and the temporary crown was digitally drawn (Dental Knowledge, Milan, Italy) and then sent to the milling machine for production with a composite monoblock. After 4 months, when the implant was osteointegrated, it was not necessary to take another dental impression, and the definitive crown could be screwed in. Conclusion. The CAD/CAM technology is especially helpful in postextraction implant for aesthetic rehabilitation, as it is possible to immediately fix a provisional crown with an anatomic shape that allows an optimal healing process of the tissues. Moreover, the removal of healing abutments, and the use of impression copings, impression materials, and dental stone became unnecessary, enabling the reduction of the chair time, component cost, and patient's discomfort. However, it is still necessary for scientific research to continue to carry out studies on this procedure, in order to improve the accuracy, the reliability, and the reproducibility of the results.

Juvenile paradental cyst: presentation of a rare case involving second molar.

The aim of this article was to describe a rare case of paradental cyst of the permanent mandibular second molar. A 14-year-old girl was referred to Oral Surgery Department, Dental Clinic, IRCSS Fondazione Ca' Granda, University of Milan, Italy, for the evaluation of the deep probing located on the buccal aspect of her erupted mandibular left second molar. Clinical signs of inflammation were absent and the mucosa around the second molar appeared clinically normal. Pulp tests for the second molar were positive. The evaluation of the panoramic radiograph did not revealed radiolucency. The Cone-beam tomography showed a well-defined semilunar-shaped radiolucency demarcated by a fine radiopaque line. The cyst was enucleated. The histopathologic analisys revealed the presence of hyperplastic, non-keratinized squamous epithelium with heavy, dense inflammatory cell infiltrate in the epitelium and connective tissue wall. This analysis associated with macroscopic, clinical and radiografic examination confirmed the diagnosis of paradental cyst. A clinic-pathologic correlation, incorporating the surgical, radiographic and histologic findings, is required to obtain the final diagnosis of paradental cyst. Today, the treatment of choice is simple enucleation and thorough curettage of the cyst without extraction of the involved tooth, but if CT demonstrates erosions in the buccal or lingual cortices, marsupialization should be the treatment of choice.

Treatment of seriously compromised teeth: decision- making criteria and treatment options.

The aim of this article was to describe the case of a patient who presented to our attention with severe periodontal disease, complicated by furcation involvement on elements 16 and 17. In addition, the radiographic exam revealed the presence of a deep intrabony defect distal to tooth 15. Surgical therapy is performed after the resolution of the endodontic component of the intra-bony defect on the element 15 and consists on osteoplasty and ostectomy on 16, guided tissue regeneration (GTR) on 15, extraction of 17 and bi-laminar connective tissue graft for the coverage of the recession on tooth 13. The patient is visited monthly and 9 months after surgery, the definitive metal-ceramic crown is delivered and adapted to tooth 16. At 18 months, the patient's periodontal situation is re-evaluated and the pocket depth results healthy (probing depth of tooth 15=2 mm). The surgical practices reported in this work allowed for functional and esthetic rehabilitation of periodontally compromised teeth. The RSR and the GTR represent conservative surgery that allow the preservation of compromised dental elements and if properly performed, guarantee excellent survival rates of the elements in the arch. For these reasons, when it is possible, the RSR and the GTR are a valid alternative to implantology and are to be considered as the first therapeutic option in the treatment plan.

Behavior of endosseous one-piece yttrium stabilized zirconia dental implants placed in posterior areas.

AIM: Considering that zirconia dental implants are indicated for the rehabilitation of highly esthetic areas, the aim of this work was to investigate the functional behavior of these implants positioned in the posterior regions of the jaws. METHODS: The study included 6 patients with 14 zirconia implants positioned in posterior (molar) areas of the jaws. Immediately after surgery, all implants were restored with temporary crowns or bridges. Clinical radiographic evaluation was performed 6 months after surgery and subsequently every year. At these follow-up visits, periodontal indexes were recorded and peri-apical radiographs were taken in order to calculate marginal bone loss. RESULTS: The success and survival rates were 100%. The modified bleeding index (mBI) and modified plaque index (mPLI) were respectively equal to 0.57±0.51 and 0.29 ± 0.47 at 4-year follow-up. The overall mean probing depth of the implants was 3.13±0.87 mm. The mean marginal bone loss was +0.665 mm 4 years after surgery. CONCLUSION: Considering the limits of our study, as regards to the data concerning peri-implant tissue health, marginal bone loss and survival and success rates of zirconium implants placed in posterior areas, we can conclude that the data reported are very encouraging although the number of implants observed is still limited.

Aesthetic restoration of upper lip after removal of post-trauma foreign body (orthodontic bracket).

AIM: Approach to dental trauma should always be based on a careful examination of the traumatised area, including both hard and soft tissues, to ascertain the presence of a foreign body and to assess the best treatment and follow-up. In this work a case of an orthodontic bracket migrated to the upper lip and retained there for 10 years, following a trauma is discussed. CASE REPORT: The patient complained symptomatic swelling of the upper lip; palpation and x-rays showed the presence of a foreign body, identified as an orthodontic bracket. Medical history revealed that patient had a dental trauma 10 years prior. The foreign body was localised and removed. At the two week follow-up visit after surgical incision of the lip, signs and symptoms (i.e. the swollen lip) were resolved. This case emphasises the importance of accurate management of the traumatic event, through proper diagnosis and therapy of both hard and soft tissues, even if the examination if the patient is performed years after the dental trauma.

Minimally invasive surgical approach in a large mandibular solitary cyst: case report and review of the literature.

Solitary bone cyst (SBC) is an intraosseus radiolucent lesions that defers from real cysts for the fact that peripheral epithelial lining is totally absent. It could be classified as a psudocyst and occurs most frequently in young patients. In most cases SBC doesn't cause symptoms and it is often diagnosed accidentally during routine radiographic examination. A right diagnosis of this disease is also complicated because there are no pathognomonic radiographic signs and symptoms: so this form of pseudocyst is often misdiagnosed as a common odontogenic cyst. Despite numerous studies, the pathogenesis of the SBC is not yet established: the most widely accepted theory is that it could be the result of an intramedullary necrosis determined by a trauma. In this article we report a case of SBC in child treated with a minimal surgical approach. This new kind of treatment is much more conservative than the traditional one, it can be performed as outpatients, under local anesthesia and with few postoperative discomfort: For these reasons this minimal invasive technique appears to be particulary suitable for pediatric patients.

Combined treatment of odontogenic keratocysts: initial marsupialization and successive enucleation with peripheral ostectomy plus Carnoy's solution application. A five-year follow-up experience.

AIM: The odontogenic keratocyst (KCOT) is a locally aggressive, cystic jaw lesion with a high growth potential and a propensity for recurrence. Considering its neoplastic features, treatments of keratocysts are required and they are generally classified as conservative or aggressive. However, although in literature there are several studies, the choice of treatment strategies remains controversial. We report a two-stage protocol based on initial marsupialization and successive enucleation. METHODS: Three cases of large KCOTs have been treated by initial marsupialization and, after a mean period of six months, successive enucleation with peripheral ostectomy and application of Carnoy's solution was performed. RESULTS: All patients were instructed in daily irrigation using chlorhexidine 0.2% during the period of marsupialization. After enucleation, good healing was obtained in all cases and from two up to five years of follow-up, there is no evidence of recurrence. CONCLUSION: Two-stage surgical treatment protocol of keratocyst leads to complete healing, preservation of important anatomical structures and absence of recurrence.

Use of fresh frozen bone graft in rehabilitation of maxillar atrophy.

AIM: Fresh frozen bone (FFB) is homologous bone obtained from human donors, provided by Tissue Banks. It is a graft material in reconstructive surgery; it is currently and widely used in orthopedic surgery and lately it has been introduced in oral and maxillofacial surgery. The purpose of this work was to show the use of fresh frozen homologous bone for bony augmentation of the maxilla and mandible in preparation for dental reconstruction with endosseous implants, as an effective alternative to harvesting and grafting autogenous bone from intra- or extra-oral donor sites. METHODS: The case presented clinically demonstrates the use of FFB grafts in the vertical augmentation of a severe maxillary atrophy in general anesthesia, and the outpatient treatment with implants insertion and prosthetic restoration. Histologic evaluation of graft biopsy six months after surgery is added to clinical assessments. RESULTS: Clinical outcome is shown with good volumetric and morphological reconstruction of the alveolar ridge without the need of a donor site. Excellent graft integration and bleeding newly formed bone was seen at the second surgical step (six months after FFB grafting), when fixation screws were removed and implant placement procedure was performed. CONCLUSION: The use of FFB in major preprosthetic surgery may be an acceptable therapeutic alternative to the autogenous block graft (harvested from iliac crest or calvarium) for its success rate as graft material. Benefits include: surgical procedure with reduced discomfort and infection risk as a second operation field to harvest the graft is avoided; FFB is safe, cheap and available in programmed amounts, its use can significantly reduce operating time.

Paradental cyst of the first molar: Report of a rare case with bilateral presentation and review of the literature.

The paradental cyst is a lesion classified and recognized by World Health Organization quite recently, which is related to an inflammatory process, especially pericoronitis, involving a tooth in eruption. The aim of this article is to report a rare bilateral case of paradental cyst. An 8-year-old boy presented to the Oral Surgery Department, Dental Clinic, Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) Fondazione Ospedale Maggiore Policlinico, University of Milan, with the complaint of swelling over the buccal gingiva of his unerupted lower left first molar. Radiographs revealed a radiolucency involving the bifurcation and root area of teeth 36 and 46. The cysts were enucleated, maintaining the affected teeth in site; microscopic evaluation revealed a chronically inflamed cyst lined by a non-keratinized stratified squamous epithelium; the histopathology associated with macroscopic and radiographic examinations permitted the definitive diagnosis of a paradental cyst on the mandibular left and right first molars. The most recent literature shows the rarity of the paradental cyst occurring with bilateral localization. Because the paradental cyst can present variable clinical and radiographic signs, it is mandatory to correlate all clinical, radiographic, and histological data to obtain a definitive diagnosis.

Use of endosseous one-piece yttrium-stabilized zirconia dental implants in premolar region: a two-year clinical preliminary report.

AIM: The aim of this work was to clinically and radiographically evaluate survival and success rate of zirconia dental implants positioned in premolar area during a follow-up period of at least 12 months up to 24 months. METHODS: Sixteen patients were treated with 26 zirconia implants. All implants received immediate temporary restorations and 6 months after surgery were definitively restored. Twelve to 14 months after implant insertion, a clinical-radiographical evaluation was performed in order to estimate peri-implant tissues health and peri-implant marginal bone loss. RESULTS: The survival rate was 96.16%. The success rate was 91.6%. CONCLUSION: Because of the limited number of implants, conclusions may not be considered significant even if results are encouraging. Further scientific information regarding clinical use of zirconia dental implants are needed, as well as prospective long-term clinical studies in order to understand if zirconia implants may represent a valid alternative to titanium implants.

Cancer cell reprogramming: stem cell differentiation stage factors and an agent based model to optimize cancer treatment.

The recent tumor research has lead scientists to recognize the central role played by cancer stem cells in sustaining malignancy and chemo-resistance. A model of cancer presented by one of us describes the mechanisms that give rise to the different kinds of cancer stem-like cells and the role of these cells in cancer diseases. The model implies a shift in the conceptualization of the disease from reductionism to complexity theory. By exploiting the link between the agent-based simulation technique and the theory of complexity, the medical view is here translated into a corresponding computational model. Two main categories of agents characterize the model, 1) cancer stem-like cells and 2) stem cell differentiation stage factors. Cancer cells agents are then distinguished based on the differentiation stage associated with the malignancy. Differentiation factors interact with cancer cells and then, with varying degrees of fitness, induce differentiation or cause apoptosis. The model inputs are then fitted to experimental data and numerical simulations carried out. By performing virtual experiments on the model's choice variables a decision-maker (physician) can obtains insights on the progression of the disease and on the effects of a choice of administration frequency and or dose. The model also paves the way to future research, whose perspectives are discussed.

Edentulous jaws rehabilitation with yttrium-stabilized zirconium dioxide implants: two years follow-up experience.

AIM: The aim of this study was to present authors' two-year clinical experience with Yttrium-stabilized zirconium dioxide implants placed in native bone or regenerated bone. METHODS: Yttrium-stabilized zirconium dioxide implants made of brezirkon (whiteSKY, Bredent medical, Senden, Germany) were used for the treatment of edentulous ridge rehabilitation in the Dental Clinic of the University of Milan (Head of the Department, Prof. F. Santoro). Zirconium dioxide is a highly resistant ceramic material obtained by cleaning zirconium dioxide and zirconium silicate. The implant used in the clinical study featured a conical one piece implant with double cylindrical thread with a sandblasted rough surface. The prosthetic section was smooth. RESULTS: Forty-six implants have been inserted in 18 patients from January 2007 to January 2009, the follow-up period was comprised between 6 and 24 months. The overall success rate was 89%; the success rate in native bone was 97% and 74% in augmented bone. It can be stated that the success rate is comparable to titanium fixtures. CONCLUSION: It would be logical to use a ceramic material for the esthetic regions; zirconium dioxide is particularly suitable since it features tissue friendliness and resistance comparable to titanium. The good mechanical properties, possibility of easy fabrication of the prosthetic restoration and the good integration into the tissue and the esthetics provide perfect preconditions for yttrium-stabilized zirconium dioxide to become the most commonly used material in implant dentistry.

Paradental cyst of the first molar: a report of two cases.

OBJECTIVE: The paradental cyst is an uncommon lesion associated with the permanent mandibular first or second molar in children just prior to tooth eruption. The purpose of this article is to present two cases of paradental cyst affecting the buccal aspect of permanent mandibular first molar of both young patients. We also discuss diagnosis, treatment and radiographic findings of the cases. PATIENTS AND METHODS: In both cases was made only the enucleation of cyst without extraction of the adjacent tooth. Lesional samples were sent for histopathologic analysis. RESULTS: The histopathologic analysis of both cases, revealed a lining of hyperplastic, nonkeratinized squamous epithelium with heavy, dense inflammatory cell infiltrate in the epithelium and connective tissue wall. The histopathology associated with macroscopic and radiographic examination permitted the definitive diagnosis of a paradental cyst on the mandibular left first molar. A follow-up of 1 year was carried out in both cases and no recurrences was noted; in the first case was observed the correct eruption of the mandibular permanent left first molar. CONCLUSIONS: A clinicopathologic correlation, incorporating the surgical, radiographic, and histological finding, is required to obtain the final diagnosis of paradental cyst. Today, the treatment of choice is simple enucleation and thorough curettage of the cyst without extraction of the involved tooth.

Displacement of a dental implant into the maxillary sinus: case series.

Dental implants placed in the maxilla risk failure because of the low density of the maxillary bone and the shortness of the maxillary ridge. Moreover, inadequate implant preparation, drilling or installation can easily lead to complications related to the maxillary sinuses. Displacement of dental implants into the maxillary sinus can cause serious complications, but there are few reports of such cases. The aim of this paper is to present three cases of a migrated dental implants into the maxillary sinus: in the first two cases the dental implant was found close to the medial wall of the maxillary sinus and was removed through a surgical approach, whereas in the third case the dental implant was spontaneously expelled from the nasal cavities through the mucociliary clearance. The most frequent adverse effect is the local infection of tissue around the implant. For this reason, implants placed close to the maxillary sinus offer a route for infection from the oral cavity to the sinus. While in some cases implant migration causes sinusitis in other, the patients remain asymptomatic; anyway, the treatment depends on the symptoms of maxillary sinusitis. In the third case the dental implant was spontaneously expelled from the nasal graves. Our report illustrates that a powerful mechanism of mucociliary action can cause relatively heavy objects within the maxillary sinus to migrate naturally to the sinus ostia against gravitational force and then to be expelled from the nasal cavities.

TGF-beta1 and VEGF after fresh frozen bone allograft insertion in oral-maxillo-facial surgery.

Bone regeneration technique using allografts is widely used in oral surgery to repair alveolar defects and to increase alveolar volume for endosseous implant insertions. Bone allografts promote the reabsorption and neo-synthesis of bone tissue, which are regulated by numerous cytokines, proteins and growth factors. In this study, six patients with insufficient alveolar volume for endosseous implant insertions, were treated with bone regeneration technique using Fresh Frozen Bone (FFB) allografts collected from the femoral head or the hip. Samples of bone graft collected during graft insertion surgery and biopsies collected six months later during implantology were fixed, decalcified and analyzed histomorphologically and morphometrically by haematoxylin-eosin staining. In addition, TGF-beta1 and VEGF were analyzed by immunohistochemistry. The histological analysis of FFBs showed wide areas of calcified bone organized in osteons intermingled with areas of non-calcified matrix containing osteoblasts. However, the regenerated alveolar bone, collected six months after the graft insertion surgery, showed wide areas of non-calcified matrix. TGF-beta1 and VEGF were less expressed in FFB than in regenerated alveolar bone.