Immediate Implant Placement Using the Socket Shield Technique: Clinical, Radiographic, and Volumetric Results Using 3D Digital Techniques-A Case Series.

Extraction-site alveolar remodeling is a major concern due to negative volumetric hard and soft tissue changes that inevitably limit rehabilitation options and diminish esthetic outcomes. Surgical techniques employed to minimize alveolar dimensional changes are not always predictable. Utilizing a socket shield with an immediate surgical implant procedure helps maintain a thin portion of the root in the vestibular area and thus minimizes bone resorption, especially at the coronal cortical aspect. This case series assesses the dimensional changes in peri-alveolar structures via superimposition of the preoperative and 6-month postoperative 3D digital quantification of soft tissue. Fifty patients with 50 sites fulfilled the inclusion criteria. Implant survival was 100%, with no incidence of complications. Tissue changes were as follows: -0.85 mm at the mesial papilla, -0.95 mm at the distal papilla, -0.7 mm at both the vertical and horizontal central margins, -0.21 mm at a distance 4 mm from the margin, and -0.64 mm at the palatal central margin. The buccal contour was clinically convex in all cases. The site with highest frequency of > 1 mm of dimensional loss was the distal papilla (42% of sites), and the site with the lowest frequency was the point 4 mm from the midfacial margin (0% of sites).

Maxillary Sinus Elevation by Crestal Window: Influence of 3D Sinus Size on Bone Regeneration-A Retrospective Clinical and Histologic Evaluation.

This evaluation correlates maxillary sinus 3D morphology with bone regeneration. In 39 patients with crestal bone ≤ 2 mm, mineralized human bone allografts were used to augment the sinus floor through the crestal window sinus elevation approach. CBCT was used to measure the buccopalatal diameter (BPD), mesiodistal diameter (MDD), and hemi-ellipsoidal volume (Vh) in all sinuses. A bone core biopsy sample was taken at implant placement (4 to 5 months after sinus augmentation). Microradiographs of methacrylate-embedded sections were used to evaluate the amounts of bone, residual graft, and soft tissue. All 51 implants placed in the 39 patients successfully osseointegrated. A linear regression analysis showed that as BPD, MMD, and Vh increased, the amount of bone gain decreased and the amount of soft tissue increased (P < .05). The amount of residual graft was little affected by sinus morphology. Microradiographic data were grouped into four different sinus types (from small to great) using BPD and Vh medians. The best amount of bone formation was achieved in the narrow and short sinus type, while no great differences were found in the remaining three sinus types. Understanding of 3D sinus cavity morphology, especially the buccopalatal diameter and mesiodistal dimensions, is fundamental for achieving the best possible sinus augmentation outcomes.

Topographic Assessment of Calcified Material After Sinus Floor Augmentation.

PURPOSE: This study aimed to topographically examine the healing of mineralized human bone allograft in sinus augmentation. MATERIALS AND METHODS: Thirty-two patients with crestal bone height ≤ 2 mm who required sinus augmentation were recruited for the study. A mixture of 80/20 cortical/cancellous mineralized human bone allografts were used to augment the sinus floor using a crestal window approach. A bone core biopsy specimen was taken at the time of implant placement, 6 months after surgery. Microradiographs of methacrylate-embedded sections were split into five longitudinal sectors (crestal to sinusal) to topographically assess the bone, graft, and fibrous tissue amount. RESULTS: All implants were osseointegrated 3 months later without any adverse effects. The polynomial (degree 2) of results (all with great correlation coefficient, P < .01) gave rise to a polynomial curve of graft percentage with a maximum at sector 4 (presinusal), a bone percentage with a minimum between sectors 3 and 4, and a fibrous tissue percentage with a maximum between sectors 3 and 4. CONCLUSION: Based upon topographic analysis, mineralized human bone allograft is capable of achieving adequate vertical bone height for implant placement. The need for a topographic analysis to assess the outcomes of sinus augmentation is emphasized.

Crestal Window Sinus Lift and Its Long-Term Clinical Outcomes.

Sinus augmentation has been shown to be an effective methodology to augment a deficient maxillary sinus. However, there are many techniques a clinician can choose from. Historically, lateral window or crestal osteotome approaches were the most frequently discussed techniques. In this paper, a sinus floor elevation technique with crestal window sinus lift was proposed to treat cases of extremely atrophic maxillae (remaining bone height ≤ 2 mm). A crestal window is opened for the sinus membrane to be detached from the bony walls. After the proper elevation and membrane detachment, human particulated allografts were placed via the crestal access window to elevate the sinus membrane. Primary closure was then achieved, and after 6 to 9 months of healing, implant placement was performed. From the long-term clinical outcome that was obtained, the authors concluded that crestal window sinus lift is a procedure with predictable outcomes for lifting a maxillary sinus floor less than 2 mm thick, with an average elevation height of 11.73 mm.

Quantitative comparison of cone beam computed tomography and microradiography in the evaluation of bone density after maxillary sinus augmentation: a preliminary study.

PURPOSE: Cone beam computed tomography (CBCT) and microradiographic analyses were comparatively performed in maxillary sinus augmentation to preliminarily verify the diagnostic potential of CBCT on the evaluation of bone regeneration. MATERIALS AND METHODS: A two-stage protocol was conducted in 19 consenting patients, all having the crestal bone ≤2 mm, in private dental office. Mineralized human bone allograft particles were used to augment sinus using lateral window approach. A succession of CBCT scans of the maxilla was taken before surgery, after sinus augmentation, and immediately after implant insertion. Using virtual probes, CBCT data were processed by medical imaging software and expressed as gray level (GL). A bone core biopsy was taken at implant placement, 6 months after surgery. Microradiography of transverse sections, taken 6, 8, and 10 mm from the crestal surface, of methacrylate-embedded biopsies was performed to analyze and to evaluate the mineralized material amount (MM%). RESULTS: A total of 21 sinus augmentations were performed. CBCT (mean GL: 646-693) data were not statistically different when comparing 6-, 8-, and 10-mm sites to after grafting/implant-insertion values. Furthermore, microradiographic (mean MM%: 45.3-48.3) data were not statistically different comparing 6-, 8-, and 10-mm sites, due to variation of values among patients. A GL and MM% parallelism was identified considering each patient, instead. A significant correlation (p < .001) between GL and MM% was found after both Wilcoxon test for paired data and simple linear regression analysis. CONCLUSIONS: The preliminary result clearly demonstrated the predictability of the CBCT analysis. Due to the limited sample and great variations of the MM% recorded in patients, further clinical and morphometric studies are needed to fulfill diagnostic expectations.

Is socket healing conditioned by buccal plate thickness? A clinical and histologic study 4 months after mineralized human bone allografting.

OBJECTIVE: The aim of this study was to clinically and histologically analyze the healing of grafted sockets by mineralized human bone allograft (MHBA) and nongrafted sockets, correlating the results with buccal plate thickness. MATERIAL AND METHODS: Thirty-one sockets were randomly split into control (CG) and treatment (MHBA grafted) (TG) groups and, subsequently, into four subgroups according to buccal plate thickness: a ≤ 1 mm and b > 1 mm. Ridge thickness, depth, and height were monitored. Four months after, at implant placement, a bone core biopsy for histologic and morphometric analyses was taken. RESULTS: The differences of buccal height (TG-a -0.27 and CG-a -1.17 mm) and width (TG-a 0.55 and CG-a 2.67 mm, TG-b 0.12 and CG-b 1.17 mm) were statistically significant. The increase in bone amount CG-b (28.17%) compared with CG-a (16.98%) was statistically significant. Soft tissue amount of TG-b (54.21%) and TG-a (56.91%) was lower than that of CG-b (71.83%) and CG-a (83.01%), both being statistically significant (P = 0.002). CONCLUSIONS: The results proved that thin buccal plates had a worse outcome on socket healing and that network formation by MBHA not only predisposes a successful implant insertion but also acts as size keeper.