Accuracy and Reliability of Cone-Beam Computed Tomography for Linear and Volumetric Mandibular Condyle Measurements. A Human Cadaver Study.

The accuracy of Cone-Beam Computed Tomography (CBCT) on linear and volumetric measurements on condyles has only been assessed on dry skulls. The aim of this study was to evaluate the reliability and accuracy of linear and volumetric measurements of mandibular condyles in the presence of soft tissues using CBCT. Six embalmed cadaver heads were used. CBCT scans were taken, followed by the extraction of the condyles. The water displacement technique was used to calculate the volumes of the condyles and three linear measurements were made using a digital caliper, these measurements serving as the gold standard. Surface models of the condyles were obtained using a 3D scanner, and superimposed onto the CBCT images. Condyles were isolated on the CBCT render volume using the surface models as reference and volumes were measured. Linear measurements were made on CBCT slices. The CBCT method was found to be reliable for both volumetric and linear measurements (CV < 3%; CCI > 0.90). Highly accurate values were obtained for the three linear measurements and volume. CBCT is a reliable and accurate method for taking volumetric and linear measurements on mandibular condyles in the presence of soft tissue, and so a valid tool for clinical diagnosis.

Implant rehabilitation of the atrophic upper jaw: a review of the literature since 1999.

The severely resorbed maxilla presents serious limitations for conventional implant placement. As a result, different techniques have been developed in the last two decades, with variable results. The most significant approaches comprise the placement of implants in anatomical abutments, elevation of the sinus floor, and reconstructive surgery with bone grafting. The present study reviews the most important articles on the management of the atrophic upper jaw published in the literature since 1999.

Implantes en arbotantes anatómicos del maxilar superior / Implants in anatomical buttresses of the upper jaw

El cráneo posee una serie de arbotantes de hueso denso que forman un armazón protector en torno a las múltiples cavidades craneofaciales. El tercio medio posee dos arbotantes anteriores (frontomaxilar y frontocigomático) y uno posterior (pterigomaxilar). Estos permiten, en algunas situaciones, la rehabilitación de extremos libres superiores en maxilares atróficos mediante la colocación de implantes con una angulación parasinusal, evitando así la utilización de técnicas más complejas como la elevación sinusal o la reconstrucción mediante autoinjerto. En este trabajo se ha realizado una revisión bibliográfica sobre la inserción de implantes en arbotantes anatómicos en el maxilar superior

The skull presents a series of dense bony buttresses that conform a protective frame around the different craniofacial cavities. The middle third portion presents two anterior buttresses (frontomaxillary and frontozygomatic) and a posterior buttress (pterygomaxillary). In certain situations these structural supports allow the rehabilitation of free upper extremities in atrophic jaws by positioning parasinusal angulated implants - thereby avoiding the need for more complex reconstruction techniques such as sinus lifting or autografting procedures. The present study presents a review of the literature on implant insertion in anatomical buttresses of the upper jaw

Implants in anatomical buttresses of the upper jaw.

The skull presents a series of dense bony buttresses that conform a protective frame around the different craniofacial cavities. The middle third portion presents two anterior buttresses (frontomaxillary and frontozygomatic) and a posterior buttress (pterygomaxillary). In certain situations these structural supports allow the rehabilitation of free upper extremities in atrophic jaws by positioning parasinusal angulated implants--thereby avoiding the need for more complex reconstruction techniques such as sinus lifting or autografting procedures. The present study presents a review of the literature on implant insertion in anatomical buttresses of the upper jaw.

Radiologic study of marginal bone loss around 108 dental implants and its relationship to smoking, implant location, and morphology.

PURPOSE: To investigate peri-implant bone resorption around 108 ITI dental implants 1 year after prosthetic loading using extraoral panoramic, conventional intraoral periapical, and digital radiologic techniques. MATERIALS AND METHODS: A total of 108 implants were placed (59 in the maxilla and 49 in the mandible) in 42 patients (16 men and 26 women) with a mean age of 44.2 years (range 14 to 68 years). Orthopantomographic, conventional periapical, and digital radiographs were obtained at loading and again 1 year later. Bone loss was calculated from the difference between the initial and final measurements. RESULTS: Mean loss in alveolar bone height was determined to be 1.36 mm by extraoral panoramic radiography, 0.76 mm by intraoral periapical radiography, and 0.95 mm by digital radiography. The implants located in the maxilla and those placed in patients who smoked 11 to 20 cigarettes per day were associated with significantly greater bone loss. DISCUSSION: The results in relation to peri-implant bone loss in the first year after loading were similar to those published by other authors. CONCLUSION: Conventional periapical films and digital radiographs were more accurate than orthopantomography in the assessment of peri-implant bone loss. Smoking and implant location in the maxilla were associated with increased peri-implant marginal bone resorption.