Gabriele Rosano

Implant survival rates after maxillary sinus augmentation

Implant therapy in the atrophic posterior maxilla becomes challenging in the presence of reduced maxillary bone height. Sinus augmentation can be performed for resolving this condition prior to implant placement. The aim of this article was therefore to evaluate implant survival rates in the grafted sinus taking into account the influence of the implant surface, graft material, and implant placement timing. A systematic review of the literature was performed. Articles retrieved from electronic databases were screened using specific inclusion criteria, and data extracted were divided according to: graft material (autogenous, non-autogenous, composite graft), implant surface (machined or textured), and implant placement (simultaneous with grafting or delayed). Fifty-nine articles were included. Survival rates for implants placed in grafts made of bone substitutes alone and grafts of composite material were slightly better than the survival rates for implants placed in 100% autogenous grafts. Over 90% of implants associated with non-autogenous grafts had a textured surface. Textured surfaces achieved better outcomes compared with machined surfaces, and this was independent of the graft material. Simultaneous and delayed procedures had similar outcomes. It may be concluded that bone substitutes can be successfully used for sinus augmentation, reducing donor-site morbidity. Long-term studies are needed to confirm the performance of non-autogenous grafts. The use of implants with a textured surface may improve the outcome in any graft type.

Maxillary sinus vascular anatomy and its relation to sinus lift surgery.

OBJECTIVES To investigate the prevalence, location, size and course of the anastomosis between the dental branch of the posterior superior alveolar artery (PSAA), known as alveolar antral artery (AAA), and the infraorbital artery (IOA). MATERIAL AND METHODS The first part of the study was performed on 30 maxillary sinuses deriving from 15 human cadaver heads. In order to visualize such anastomosis, the vascular network afferent to the sinus was injected with liquid latex mixed with green India ink through the external carotid artery. The second part of the study consisted of 100 CT scans from patients scheduled for sinus lift surgery. RESULTS An anastomosis between the AAA and the IOA was found by dissection in the context of the sinus anterolateral wall in 100% of cases, while a well-defined bony canal was detected radiographically in 94 out of 200 sinuses (47% of cases). The mean vertical distance from the lowest point of this bony canal to the alveolar crest was 11.25 ± 2.99 mm (SD) in maxillae examined by CT. The canal diameter was <1 mm in 55.3% of cases, 1-2 mm in 40.4% of cases and 2-3 mm in 4.3% of cases. In 100% of cases, the AAA was found to be partially intra-osseous, that is between the Schneiderian membrane and the lateral bony wall of the sinus, in the area selected for sinus antrostomy. CONCLUSIONS A sound knowledge of the maxillary sinus vascular anatomy and its careful analysis by CT scan is essential to prevent complications during surgical interventions involving this region.

Maxillary sinus vascularization: A cadaveric study

The goal of this study was the investigation of the arterial blood supply to the maxillary sinus to give clinicians the basis for a better understanding of the origin of vascular complications that can derive from surgical procedures at this level. The study consisted of 30 sinuses from 15 human cadavers with an age range of 59 to 90 years. To define the complex vascularization of the maxillary sinus, the afferent vascular network was injected with liquid latex mixed with red india ink through the external carotid arteries. An intraosseous anastomosis between the dental branch of the posterior superior alveolar artery, also known as alveolar antral artery, and the infraorbital artery was found in 100% of cases. Such an anastomosis seemed to guarantee the blood supply to the sinus membrane, to the periosteal tissues, and especially to the anterior lateral wall of the sinus. Moreover, the gingival branch of the posterior superior alveolar artery was found to anastomose an extraosseous branch of the infraorbital artery in 10 sinuses. The examination of the maxillary sinus also showed a close anatomic relationship among the sinus posterior wall, the descending palatine artery, and the sphenopalatine artery in all 30 sinuses. Small branches deriving from the posterior lateral nasal arteries have been found to perforate the nasal wall laterally and reach the mucosa of the maxillary sinus. A sound knowledge of the maxillary sinus vascularization is essential to prevent vascular complications during surgical operations involving this region.

Anatomic assessment of the anterior mandible and relative hemorrhage risk in implant dentistry: a cadaveric study

OBJECTIVES To evaluate prevalence, size, location and content of foramina and bony canals located on the lingual side of the mandibular midline. MATERIAL AND METHODS The prevalence and the size of midline lingual foramina and canals visible above and/or below genial spines and their distances from the mandibular base were measured in 60 dry mandibles from adult human cadavers. In addition, macro-anatomic dissections were performed on another 20 mandibles injected with red latex to investigate the vascular canal contents associated with these midline lingual foramina and canals. RESULTS A total of 118 foramina were detected. All mandibles investigated had at least one lingual foramen at the midline above the genial spines, located at a mean height of 12.5+/-2.1 mm (SD) from the inferior border of the mandible. Macro-anatomic dissections showed a clear vascular branch entering the mandibular midline as a single vessel from a sublingual-sublingual anastomosis in 19 out of 20 mandibles studied (95%). CONCLUSION Blood vessels in the floor of the mouth may be in close proximity to the lingual cortical plate of the mandibular midline in most cases. This implies that bleeding can occur when the mandibular cortical plate is perforated even minimally. As a consequence, the authors suggest a careful planning of implant positioning at mandibular midline, possibly opting for the use of an even number of implants in the interforaminal region, avoiding the risk of surgical trauma to the lingual cortical plate of the mandibular midline.

Maxillary Sinus Septa: A Cadaveric Study

PURPOSE The goal of this study was to investigate the incidence, location, and height of antral septa and to offer the clinician, through an accurate investigation of the anatomy of the maxillary sinus region, the tools to carry out sinus-lift procedures under safe conditions. MATERIALS AND METHODS The study consisted of 60 sinuses from 30 human cadavers with an age range of 59 to 90 years. Only septa measuring 3.0 mm or greater in height were considered in our analysis. RESULTS A total of 20 incomplete septa were found, showing an incidence of 33.3%, and no more than 1 septum per sinus was identified. All septa were located in the anterior-lateral wall and were either sagittal or transversal. Of the septa, 6 (30%) were located in the anterior region of the antral wall (between the second premolar and first molar roots), 8 (40%) were in the middle region (between the first and second molar roots), and 6 (30%) were in the posterior region (distal to the third molar roots). Antral septa height showed great variability, with a mean value of 8.72 mm (SD, 4.26; range, 3.7-18.4 mm). Our study also showed that 40% of our specimens (12 of 30 maxillas) have bony septa that can partially divide the sinus, and they were symmetric in 8 of 12 cases. CONCLUSIONS A sound knowledge of the maxillary sinus anatomy and of the possible anatomic variations is essential to prevent complications during surgical interventions involving this region.

Scanning electron microscopic analysis of the integrity of the root-end surface after root-end management using a piezoelectric device: a cadaveric study.

INTRODUCTION The introduction of piezoelectric instruments in endodontic surgery allowed clinicians to manage the bone tissue with precision reducing the risk of damaging soft tissues. Although such instruments can also be used to prepare root-end cavity, few information is available on the effect of piezosurgery on dentine. This cadaveric study investigated the integrity of root apices after root-end cavity preparation by piezoelectric instruments at different device settings. METHODS Fifty maxillary anterior teeth underwent endodontic treatment and apical resection in situ. Ten teeth were used as control. Retrograde cavities were prepared in 40 teeth (10 per group). In three groups, the piezoelectric device was set at constant vibration mode (CV), and three power levels were used. In another experimental group (n = 10), vibration + pulsation mode (VP) was selected, and low power was used. Each root was duplicated and analyzed by scanning electron microscopy for the presence of cracks and marginal chipping. RESULTS The number of cracks was significantly higher in the VP group, whereas no significant difference was found among CV groups. No difference between groups was found for crack type. The VP group showed a significantly poorer quality of cavity margin respect to the CV groups. CONCLUSION Constant vibration mode is recommended for retrograde preparation with piezosurgery.

Treatment of through-and-through bone lesion using autologous growth factors and xenogeneic bone graft: a case report

BackgroundThis pilot case study aimed at evaluating the possibility of achieving optimal hard and soft tissue regeneration using plasma rich in growth factors (PRGF) and anorganic bovine bone (ABB) for the surgical treatment of a large through-and-through periapical bone lesion.Case reportMaxillary incisors of a patient with through-and-through periapical lesion of endodontic origin were treated using modern endodontic surgical technique with the adjunct of PRGF. The PRGF clot was positioned over the palatal side of the lesion while the remaining bone defect was grafted with PRGF and ABB. A collagen membrane embedded with plasma very rich in growth factors covered the graft. Post-operative pain and swelling were negligible, and soft tissue healing was very fast. One-year clinical and radiographic outcome showed complete healing and functionality.DiscussionThe addition of PRGF to ABB could improve the regenerative process, reducing postoperative symptoms and resulting in a fast and predictable hard and soft tissue healing.

Immediate postextraction implant placement using plasma rich in growth factors technology in maxillary premolar region: a new strategy for soft tissue management.

Achieving an excellent aesthetic outcome in postextraction dental implant placement in the anterior maxilla is a challenging procedure for clinicians. In fact, there is an increased risk for soft tissue recession at the facial aspect which may require supplementary connective tissue grafts to accomplish the final aesthetic result. The aim of this case report is to describe a regenerative technique using autologous plasma rich in growth factors fibrin plug for preservation of soft tissue architecture around an implant immediately placed into an extraction site in the anterior maxilla. Such a procedure allowed for guided bone regeneration without the need for vertical releasing incisions and primary healing, thus showing a pleasant gingival contour at the facial aspect after a single stage surgery. Integrating this technique into common practice could provide important benefits for the patients regarding aesthetics, without any risk of infection or transmission of diseases.

Management of the Alveolar Antral Artery During Sinus Floor Augmentation Procedures

n irradiated maxillas. Please allow me to share my experince and reasoning for this worry. I see lots of irradiated patients at our center as a result of reatment for nasopharyngeal carcinoma. On one occasion, n oroantral communication (5 mm in diameter) was creted in one of these patients after the removal of 2 carious oots of the upper left molar tooth. The first attempt to lose the defect—by use of a standard buccal sliding flap— ailed, after which a Bichat’s buccal fat pad flap was used. nfortunately, this also failed. In hindsight, this failure temmed from undiagnosed osteoradionecrosis of the maxlla. A few years earlier, the patient’s upper left third molar ven dropped off by itself, most likely because of osteoraionecrosis. Hence the action of removing the roots inicted more trauma and resulted in an oroantral defect. The efect was closed with an obturator after the patient reused to undergo hyperbaric oxygen therapy and further urgery. Besides this failure, the patient also received a scare from he consultant otorhinolaryngologist who treated him when e went for a follow-up not too long after the attempt to lose the defect with a Bichat’s buccal fat pad flap. The torhinolaryngologist, who had never seen a Bichat’s bucal fat pad, thought there were recurrences growing hrough the maxilla and the cheek area upon seeing this ap! Lessons learned from this experience were as follows:

Replacement of vertically root-fractured endodontically treated teeth with immediate implants in conjunction with a synthetic bone cement

Purpose:The purpose of this prospective study was to evaluate the clinical outcome of implants immediately placed into fresh extraction sockets for the replacement of endodontically treated teeth with signs of vertical root fracture. Material:Sixteen partially edentulous patients, with 1 tooth scheduled for extraction and showing clinical signs and symptoms and/or radiological evidence of vertical root fracture, were included in the study. Sixteen transmucosal implants were installed immediately after extraction and careful debridement. The gap between the implant surface and the socket walls was filled using synthetic bone grafting cement. Prosthetic phase occurred 3 to 4 months after surgery. Implant success and survival and radiographic bone loss were evaluated after 1 year of function. Patient satisfaction for mastication function, phonetics, and aesthetics was also assessed by means of a questionnaire. Results:No implant failure occurred. The overall implant success and survival was 100% at 1 year. The mean follow-up was 13.5 months. All prostheses were successful. Periimplant bone loss after 1 year averaged 0.48 ± 0.20 mm. All patients reported full satisfaction for mastication function, phonetics, and aesthetics. Conclusions:The use of a synthetic bone grafting cement in combination with immediate implant placement procedure can be considered a safe, effective, and predictable treatment option for the rehabilitation of fresh postextraction sockets.