Academic literature on the topic 'Osseous housing'

The craniovertebral junction (CVJ) has unique anatomical structures that separate it from the subaxial cervical spine. In addition to housing vital neural and vascular structures, the majority of cranial flexion, extension, and axial rotation is accomplished at the CVJ. A complex combination of osseous and ligamentous supports allow for stability despite a large degree of motion. An understanding of anatomy and biomechanics is essential to effectively evaluate and address the various pathological processes that may affect this region. Therefore, the authors present an up-to-date narrative review of CVJ anatomy, normal and pathological biomechanics, and fixation techniques.

Missing teeth should be replaced as soon as possible to maintain arch integrity and thereby avoid both morphologic and functional derangements in the occlusion. Otherwise, changes occur that upset the masticatory system, such as extrusion of the teeth opposing the edentulous areas along with their alveolar housing, their supporting tissues and ultimately the maxillary sinus. Concurrently with extrusion, shifting of the interproximal contacts and migration of the adjacent teeth occur, thereby impairing function and causing disharmony. Good oral health cannot be achieved when changes in tooth position alter the coronal contour and occlusion interfering with mutual support, which encourages food impaction and retention, further leading to osseous defects.

Background. This study aimed to develop a classification for the sagittal root positioning (SRP) of mandibular anterior teeth in terms of their anterior buccal bone for use before placing immediate implants. Methods. A retrospective review of CBCT images was conducted on 150 patients (75 males and 75 females; mean age: 47.5 years) who met the inclusion criteria. The root position of the tooth samples was classified as buccal, middle, or lingual types according to their respective sagittal position and subtypes a, b, c, or d, according to the morphology of their osseous housing. Results. The frequencies of the root positions of each classified group of the sample teeth were as follows: 14% buccal type, 77% middle type, and 8% lingual type; 18.0% subtype a, 4.33% subtype b, 75.55% subtype c, and 2.11% subtype d. As a complementary procedure for data collection, the sagittal position of the apex was classified into Class I (buccally angulated apex: 4.6%), Class II (apex with no angulation: 78.2%), Class III (lingually angulated apex: 0.7%) and Class IV (exposed root: 16.3%). In addition, the results of the examination of the buccal undercut showed that in 1.6%, 32.0%, and 66.3% of the sample teeth, the undercut was located coronally, medially, and apically, respectively. Conclusion. Considering these results, the newly proposed SRP classification system can be used to study the mandibular anterior buccal bone morphology as a diagnostic tool for immediate implant treatment.

The aim of this study was to establish a classification system for use in immediate implant placement by examining fresh extraction sockets in maxillary premolars and evaluation of the varying morphologies using CBCT imaging. Selection criteria included dentulous patients ages 15-85 that had CBCT imaging taken for varying treatment. A total of 400 maxillary premolars were classified by their root morphology as Type I (two-rooted premolar with interradicular bone), II (fused roots with mesiodistal alveolar constriction) or III (single blunted root with no interradicular bone). The internal root angle was measured for all Type 1 maxillary first premolars (n=40), as well as the interradicular septal bone height. A Type 1 premolar socket is present in 32% of the sampled maxillary first and second premolars. Type 2 socket was present in 22% of premolars, and type 3 socket was present in 46% of premolars. The average internal angle formed between the long axis of the crown versus the long axis of the palatal root was 11.46 ± 4.35° (range 4° to 20.7°). The average interradicular septal bone height was of 6.9 ± 1.6 mm (range 3.28 to 9.61). Type I root form had the highest incidence at maxillary first premolars sites and has the most alveolar bone available, thus having a higher probability for primary stability. The type III root form is most common in the maxillary second premolar site and has the least amount of alveolar support for immediate implant placement. The angulation and alveolar bone support provided by the palatal root in Type I root form maxillary first premolar sites may provide stability for an immediate implant at an appropriate prosthetic position.