Sinus floor augmentation using mineralized freeze-dried bone allograft combined with recombinant human bone morphogenetic protein-2 (rhBMP-2): A long-term retrospective study.

Background/purpose: The combination of recombinant human bone morphogenetic protein-2 (rhBMP-2) with a carrier material has not been extensively studied. This study aimed to evaluate the clinical, radiological, and histomorphometric outcomes of sinus floor augmentation using a 3:7 mixture of cancellous and cortical freeze-dried bone allografts (mixed AG) combined with rhBMP-2. Materials and methods: Mixed AG was used for sinus floor augmentation in a total of 21 patients with a residual alveolar bone height <5 mm. Among the total 47 sites, augmentation with and without rhBMP-2 was performed in 26 and 21 sites, respectively. Radiographic parameters were assessed using cone-beam computed tomography. After a six-month healing period, core biopsies were harvested for histomorphometric analysis. Results: The bone gain after healing was 13.36 ± 3.9 mm and 12.07 ± 3.8 mm in the mixed AG alone and mixed AG with rhBMP-2 groups, respectively. The survival rate of implants in both groups was 100% during the follow-up period. The proportion of newly formed bone was 24.6 ± 10.2% and 39.7 ± 18.3% in the mixed AG alone and mixed AG with rhBMP-2 groups, respectively (P < 0.05). Moreover, the percentage of residual graft material was 21.0 ± 12.2% and 9.6 ± 10.0% in the mixed AG alone and mixed AG with rhBMP-2 groups, respectively (P < 0.05). Conclusion: Mixed AG combined with rhBMP-2 could be a suitable material for sinus floor augmentation. This combination may reduce the treatment time and improve the predictability of implant placement.

Technical Note on Vestibuloplasty around Dental Implants Using Erbium YAG Laser-Assisted Periosteal Fenestration (LA-PF).

Various vestibuloplasty techniques have been reported to increase the attached mucosa (AM) and vestibular depth around dental implants. However, these surgical methods have disadvantages, such as limitations in manipulation, necessity of suturing, postoperative discomfort, swelling, and pain. This study aimed to evaluate the efficacy of laser-assisted periosteal fenestration (LA-PF) in treating patients with a shallow vestibule and insufficient AM around dental implants. LA-PF was performed using an Erbium YAG laser (Er:YAG laser). First, a partial-thickness, apically positioned flap was used. A horizontal periosteal fenestration was performed using an Er:YAG laser to expose the bones. Periosteal suturing was not required. After 12 months, sufficient AM and deep vestibules were obtained and maintained. Thus, the LA-PF technique may be a simple and predictable treatment modality for shallow vestibules with insufficient AM around dental implants.

Sinus floor augmentation using mixture of mineralized cortical bone and cancellous bone allografts: Radiographic and histomorphometric evaluation.

BACKGROUND/PURPOSE: Due to the pneumatization of the maxillary sinus, the sinus floor augmentation is often performed to implant placement in the maxillary posterior region. The aim was to perform radiographic and histomorphometric evaluation after placement of mixed allografts (cortical freeze-dried bone allograft [FDBA] 50%:cancellous FDBA 50%) during sinus floor augmentation. MATERIALS AND METHODS: In 37 patients, anorganic bovine bone (ABB, sites = 16), mineralized cancellous bone allograft (MCBA, sites = 15), and mixed allografts (Mixed AG, sites = 20) were placed during sinus floor elevation via the lateral approach (LSFE), at total 51 sites with residual alveolar bone height (RBH) < 5 mm. Cone-beam computed tomography images were obtained before LSFE (T0), after surgery (T1), and 6 months after surgery (T2) for radiographic analysis. After a 6-month healing period, core biopsies were harvested and histomorphometric analysis was performed. RESULTS: The mean augmented bone height (ABH) of ABB, MCBA, and mixed AG groups after surgery was similar (13.86 ±â€¯4.19 mm, 13.99 ±â€¯4.07 mm, and 14.20 ±â€¯3.12 mm, respectively; P > 0.05). The mean ABH of ABB, MCBA, and mixed AG groups after 6 months was similar (13.72 ±â€¯4.55 mm, 11.83 ±â€¯3.31 mm, and 12.53 ±â€¯2.97 mm, respectively; P > 0.05). In the ABB, MCBA, and mixed AG groups, the proportion of newly formed bone (NB) was similar (36.13 ±â€¯10.01%, 39.26 ±â€¯10.72%, and 31.27 ±â€¯18.31%, respectively; P > 0.05). CONCLUSION: This result demonstrated that mixed AG led to sufficient bone augmentation and histologically comparable NB formation as compared to ABB and MCBA for sinus floor augmentation.

Technical Note on Root Coverage of Lower Anterior Teeth Using a Partially Deepithelialized Connective Tissue Graft (PE-CTG) Aided by a High-Speed Handpiece.

Root coverage in the mandibular anterior region is challenging because of a thin gingival biotype, shallow vestibule, and high frenum attachment. Several methods have been introduced to predict the root coverage in this area. Stimmelmayr proposed a method of performing root coverage using a combination epithelialized-subepithelial connective tissue graft (CTG). However, it is difficult to precisely acquire connective tissue according to this method. Therefore, in this case report, we would like to introduce a technique to harvest a partially deepithelialized CTG (PE-CTG) aided by a high-speed handpiece, which helps in procuring the graft easily and quickly. This method could lower the patient's morbidity at donor sites and enhance the healing process. Additionally, it could increase the amount of keratinized gingiva in the mandibular anterior region without reducing the vestibular depth. Therefore, PE-CTG using a high-speed handpiece can be a promising treatment option for the root coverage of the mandibular anterior teeth.

Morphological assessment of the anterior loop of the mandibular canal in Koreans.

The mandibular canal divides into the mental and incisive canals at the premolar region, forms the anterior loop which crosses anterior to the mental foramen, and turns back to reach the mental foramen. The aim of this study was to elucidate the general anatomical structure of the anterior loop of the mandibular canal using morphometry. Twenty-six hemimandibles from 19 cadavers (16 males, 3 females; mean age at death, 54.4 years) were studied by meticulous dissection with the aid of a surgical microscope. The location of the anterior loop, the diameters of the mandibular, mental, and incisive canals, and their distances from bony landmarks were measured using digital calipers. The anterior loop of the mandibular canal was located 3.05±1.15 mm (mean±SD) anterior to the anterior margin of the mental foramen and 2.72±1.41 mm inferior to the superior margin of the mental foramen, and was 4.34±1.46 mm long. The diameters of the mandibular, mental, and incisive canals were 2.8±0.49, 2.63±0.64, and 2.22±0.59 mm, respectively. The distances between the inferior border of the mandible and each of these canals were 7.82±1.52, 10.11±1.27, and 9.08±1.66 mm, respectively. The anterior loop of the mandibular canal was located a mean of 3.1 mm anterior and 2.7 mm inferior to the mental foramen, and continued upward and backward into the mental canal, and forward into the incisive canal. These detailed morphological features of the anterior loop of the mandibular canal represent useful practical anatomical knowledge regarding the interforaminal region.