Clinical characteristics of local allergic rhinitis sensitized to house dust mites in Asia.

PURPOSE: Local allergic rhinitis (LAR) is characterized by a localized nasal allergic response without evidence of systemic atopy. LAR is an underdiagnosed entity and is a diagnostic and therapeutic challenge for clinicians. This study aimed to investigate the prevalence and clinical characteristics of patients with LAR to house dust mites (LAR-HDM) in Korea. METHODS: We performed a retrospective chart review of 336 adult patients with rhinitis symptoms who visited the Rhinologic Clinic at Korea University Guro Hospital from October 2019 to April 2021. Using results of the skin prick test, serologic test, and nasal provocation test, patients were classified as allergic rhinitis (AR) to HDM (AR-HDM), AR to other allergens, non-allergic rhinitis (NAR), or LAR-HDM. We excluded patients with AR to other allergens and compared the clinical characteristics of the remaining three groups. Patient demographic data were reviewed, and patients' nasal symptoms, olfactory function, serum total IgE, and severity of accompanying rhinosinusitis were evaluated. RESULTS: In total, 336 patients were examined. AR-HDM was diagnosed in 138 (41.1%) patients, AR to other allergens in 36 (10.7%) patients, NAR in 21 (42.0%) patients, and LAR-HDM in 21 (6.3%) patients. The mean age of patients with LAR-HDM was significantly higher than that of patients with AR-HDM. There were no significant differences in sex, smoking history, asthma, and family history of allergic diseases between the groups. Compared to NAR patients, there were significantly more patients with LAR-HDM who had persistent nasal symptoms. The frequency of nasal itching and sneezing was significantly higher in the LAR-HDM group than in the NAR group. The olfactory function score in the LAR-HDM group was significantly worse than that in the AR-HDM group, and the Lund-Mackay score was significantly higher in the LAR-HDM group than in the other groups. CONCLUSION: Clinical history and nasal symptoms are very similar in LAR-HDM and AR-HDM. Clinicians should take more care to differentiate them. LAR-HDM should also be considered in patients with persistent and severe nasal symptoms without systemic atopy.

Clinical and imaging features of ethmomaxillary sinus compared to Haller's cell.

PURPOSE: Understanding the anatomy of the paranasal sinuses and their variations is essential to achieving safe and effective endoscopic sinus surgery. The ethmomaxillary sinus (EMS) is a relatively under-researched anatomical variation. This study investigated the prevalence, clinical features, and effect of EMS on the maxillary sinus in comparison with Haller's cells. METHODS: Patients who visited the Rhinology Clinic at our hospital for rhinologic symptoms between January 2020 and December 2020. Computed tomography (CT) scans of paranasal sinuses were obtained at 1 mm-section thickness. Using CT scans, we investigated the clinical features of EMS, measured maxillary sinus volume, and analyzed the presence of maxillary sinusitis. RESULTS: EMS was observed in 26 of the 250 patients (10.4%). The male-to-female ratio was equal. The age ranged from 18 to 83 years (mean age, 56.3). Of the patients with EMS, 65.4% were unilateral and 34.6% were bilateral. The prevalence of Haller's cells was similar to that in EMS (10.8%). In the analysis of patients with unilateral EMS, the EMS side was found to have a significantly reduced maxillary sinus volume compared to the opposite side, whereas the difference was not significant in Haller's cells. There was no significant relationship between EMS or Haller's cells and maxillary sinusitis. CONCLUSIONS: EMS can significantly affect maxillary sinus volume. Therefore, surgeons should thoroughly review PNS CT scans before paranasal sinus surgery to determine the presence and features of EMS.

Complications of Nasopharyngeal Swabs and Safe Procedures for COVID-19 Testing Based on Anatomical Knowledge.

Nasopharyngeal swabs have been widely to prevent the spread of coronavirus disease 2019 (COVID-19). Nasopharyngeal COVID-19 testing is a generally safe and well-tolerated procedure, but numerous complications have been reported in the media. Therefore, the present study aimed to review and document adverse events and suggest procedural references to minimize preventable but often underestimated risks. A total of 27 articles were selected for the review of 842 related documents in PubMed, Embase, and KoreaMed. The complications related to nasopharyngeal COVID-19 testing were reported to be rarely happened, ranging from 0.0012 to 0.026%. Frequently documented adverse events were retained swabs, epistaxis, and cerebrospinal fluid leakage, often associated with high-risk factors, including severe septal deviations, pre-existing skull base defects, and previous sinus or transsphenoidal pituitary surgery. Appropriate techniques based on sufficient anatomical knowledge are mandatory for clinicians to perform nasopharyngeal COVID-19 testing. The nasal floor can be predicted by the line between the nostril and external ear canal. For safe testing, the angle of swab insertion in the nasal passage should remain within 30° of the nasal floor. The swab was gently inserted along the nasal septum just above the nasal floor to the nasopharynx and remained on the nasopharynx for several seconds before removal. Forceful insertion should be attempted, and alternative examinations should be considered, especially in vulnerable patients. In conclusion, patients and clinicians should be aware of rare but possible complications and associated high-risk factors. The suggested procedural pearls enable more comfortable and safe nasopharyngeal COVID-19 testing for both clinicians and patients.

miR-29b Regulates TGF-ß1-Induced Epithelial-Mesenchymal Transition by Inhibiting Heat Shock Protein 47 Expression in Airway Epithelial Cells.

Tissue remodeling contributes to ongoing inflammation and refractoriness of chronic rhinosinusitis (CRS). During this process, epithelial-mesenchymal transition (EMT) plays an important role in dysregulated remodeling and both microRNA (miR)-29b and heat shock protein 47 (HSP47) may be engaged in the pathophysiology of CRS. This study aimed to determine the role of miR-29b and HSP47 in modulating transforming growth factor (TGF)-ß1-induced EMT and migration in airway epithelial cells. Expression levels of miR-29b, HSP47, E-cadherin, α-smooth muscle actin (α-SMA), vimentin and fibronectin were assessed through real-time PCR, Western blotting, and immunofluorescence staining. Small interfering RNA (siRNA) targeted against miR-29b and HSP47 were transfected to regulate the expression of EMT-related markers. Cell migration was evaluated with wound scratch and transwell migration assay. miR-29b mimic significantly inhibited the expression of HSP47 and TGF-ß1-induced EMT-related markers in A549 cells. However, the miR-29b inhibitor more greatly induced the expression of them. HSP47 knockout suppressed TGF-ß1-induced EMT marker levels. Functional studies indicated that TGF-ß1-induced EMT was regulated by miR-29b and HSP47 in A549 cells. These findings were further verified in primary nasal epithelial cells. miR-29b modulated TGF-ß1-induced EMT-related markers and migration via HSP47 expression modulation in A549 and primary nasal epithelial cells. These results suggested the importance of miR-29b and HSP47 in pathologic tissue remodeling progression in CRS.

Histomorphometric analysis of maxillary sinus augmentation with calcium phosphate nanocrystal-coated xenograft.

OBJECTIVE: The purpose of this study was to evaluate the histomorphometric result from maxillary sinus augmentation with calcium phosphate nanocrystal-coated bovine bone (Biocera). STUDY DESIGN: Maxillary sinus augmentations were performed on 10 patients with the delayed placement of implants. The lateral bony window was created using a piezoelectric saw, and the sinus membrane was elevated to make a new compartment. Biocera was grafted. The bony window was repositioned over the bone graft. In all cases, samples were taken for biopsy at the time of implant placement, 6 to 8 months after the grafting procedure. RESULTS: None of the 10 patients had complications, and there were no clinical and radiographic signs of infection. Histomorphometrically, 25.94% (± 11.24%) of newly formed bone, 52.67% (± 12.60%) of soft tissue, and 21.38% (± 10.76%) of residual grafts were shown. Histologic findings showed newly formed bone surrounding the residual grafted particles, without inflammation. Newly formed bone along inner surface of the repositioned bony window area showed more mature and dense bone structure than new bone formed along bone graft. CONCLUSION: The present study revealed that calcium phosphate nanocystal-coated xenograft was considered to be a suitable bone graft material for maxillary sinus augmentation.

Comparison of two kinds of bovine bone in maxillary sinus augmentation: a histomorphometric study.

PURPOSE: The purpose of this study was to compare the histomorphometric from sinus augmentation with calcium-phosphate nanocrystal-coated bovine bone (Biocera) and anorganic bovine bone matrix (Bio-Oss). MATERIALS AND METHODS: Bilateral maxillary sinus augmentations were performed on 5 patients with delayed placement of implants. The lateral bony window was created using a piezoelectric saw, and the sinus membrane was elevated to make a new compartment. Bio-Oss was grafted in one sinus as the control group and Biocera was grafted in the opposite sinus as the test group. The bony window was repositioned over the bone graft. In all cases, samples were taken for biopsy at the time of implant placement, 6 to 8 months after the grafting procedure. Independent t tests were used to examine between-group differences. RESULTS: None of the 5 patients had complications during healing period. Histomorphometrically, the Bio-Oss group showed 28.46% (±5.28%) of newly formed bone. Biocera group showed 29.94% (±8.72%) of newly formed bone. Newly formed bone along inner surface of repositioned bony window area showed more mature and dense bone structure than new bone formed along bone graft. CONCLUSIONS: This study revealed that both bovine bone grafts were considered as suitable bone graft materials for maxillary sinus augmentation.

Flapless transcrestal sinus augmentation using hydrodynamic piezoelectric internal sinus elevation with autologous concentrated growth factors alone.

PURPOSE: The purpose of this retrospective study was to evaluate the success rate of implants and the amount of sinus augmentation using the flapless hydrodynamic piezoelectric internal sinus elevation (HPISE) technique with autologous concentrated growth factors (CGF) alone. MATERIALS AND METHODS: A total of 11 maxillary sinuses were augmented using the HPISE technique through the flapless transcrestal approach. Sixteen implants (average 11.38 mm in length and 4.83 mm in diameter), with 2 different surfaces, were placed simultaneously with CGF alone. Plain panoramic radiograms and cone-beam computed tomograms (CBCT) were taken in all patients to evaluate the sinus augmentation preoperatively and postoperatively. RESULTS: The sinus membranes were successfully elevated, averaging 13.95 ± 6.61 mm in immediate postoperative CBCT without any iatrogenic perforation. After an average 23.8 weeks, the average bone gain above the sinus floor was 8.23 ± 2.88 mm in the axial aspect of CBCT. No complications were recorded in any patients during the follow-up period. CONCLUSION: The flapless transcrestal approach to the sinus augmentation using the HPISE technique with autologous CGF alone could be an alternative to the lateral approach, even at severely resorbed edentulous posterior maxilla with insufficient bone height.

Benefit of the replaceable bony window in lateral maxillary sinus augmentation: clinical and histologic study.

PURPOSE: This retrospective study demonstrates, by clinical and histologic evaluation, the benefit of the replaceable bony window as a homologous bony barrier in lateral sinus augmentation. MATERIALS AND METHODS: A total of 103 maxillary sinus augmentations were performed using a piezoelectric device and a Er,Cr:YSGG laser apparatus. The detached bony windows were repositioned over various bone grafts. Sixteen bone biopsy specimens were harvested at the time of uncovering or implant placement. RESULTS: Three sinuses developed postoperative infections (2.91%). After 6 to 8 months of healing, uncovering procedures were carried out. Radiographically, reconstruction of the lateral sinus wall was observed in all cone-beam computed tomogram. Clinically, complete bone healing between the replaceable bony window and the lateral sinus wall was observed in all cases, except for the 3 infected sinuses (100 sinuses, 97.09%). Histologically, favorable new bone formation was observed in all specimens without any fibrous connective tissue invagination. More mature bone was observed along the floor of the replaceable bony window than at the center of the graft site. CONCLUSION: This study demonstrates that the replaceable bony window acts as an osteoinductive homologous barrier membrane over various bone graft materials and accelerates new bone formation in lateral sinus augmentation.

Comparative histomorphometric analysis of maxillary sinus augmentation with absorbable collagen membrane and osteoinductive replaceable bony window in rabbits.

PURPOSE: The aim of this animal study was to evaluate, through histomorphometric evaluation, bone regeneration in rabbit maxillary sinuses with absorbable collagen membranes and osteoinductive replaceable bony windows over bone grafts. MATERIALS AND METHODS: Bilateral sinus augmentation procedures were performed in 16 adult male rabbits. The rabbits were randomly assigned to 4 groups of 4 rabbits each. Rectangular replaceable bony windows were made with a piezoelectric thin saw insert. In control group, grafted ß-tricalcium phosphate (ß-TCP) was covered by absorbable collagen membranes. In experimental groups, ß-TCP was grafted and covered by replaceable bony windows. The rabbits were killed at 1, 2, 4, and 8 weeks postoperatively. The augmented sinuses were stained with hematoxylin-eosin and Masson trichrome stains and examined, under light microscopy, for newly formed bone and soft tissue changes in the maxillary sinuses. RESULTS: Histologically, significantly higher and faster new bone formation was observed in the augmented sinuses of the experimental groups, receiving homologous replaceable bony windows than in those of the control group receiving collagen membranes. CONCLUSION: This study demonstrates that, for augmentation, the use of the homologous replaceable bony window over bone graft material on the maxillary sinus accelerates bone regeneration.

Effect of Air Pollutants on Allergic Inflammation in Structural Cells of the Nasal Mucosa.

OBJECTIVES: Air pollution is an increasing global concern, and its effect on allergic inflammation has attracted the attention of many researchers. Particulate matter (PM) is a major component of ambient air pollution, and heavy metals are the primary toxic constituents of PM. As previous studies on the impact of air pollutants on allergic inflammation did not adequately mimic real-world atmospheric exposure, we developed an experimental model to investigate the effects of aerosolized air pollutants on nasal epithelial cells and fibroblasts. METHODS: We collected particulate matter 2.5 (PM2.5) samples from ambient 24-hour air samples obtained in Seoul from August 2020 to August 2022, and then conducted component analysis for metallic constituents. Primary nasal epithelial cells and nasal fibroblasts, obtained and cultured from the turbinate tissues of human participants, were treated with PM2.5. The associations of heavy metals identified from the component analysis with cytokine expression were investigated. A three-dimensional (3D)-hybrid culture model, consisting of co-culture of an air-liquid interface and nasal fibroblast spheroids, was constructed to observe the impact of aerosolized air pollutants. RESULTS: Among the heavy metals, Si was the predominant component of PM2.5, and Zn showed the highest correlation with the concentration of PM2.5 in Seoul. PM2.5, Zn, and Si increased the production of epithelial cell-derived cytokines, and PM2.5 and Zn exhibited similar trends with one another. Exposure of the 3D-hybrid model to aerosolized PM2.5 and Zn resulted in elevated periostin, alpha-smooth muscle actin, and fibronectin expression in fibroblast spheroids, and those without an epithelial barrier exhibited a similar increase in periostin expression. CONCLUSION: Ambient air pollutants in the form of aerosols increase the expression of allergic inflammatory cytokines in both nasal epithelial cells and fibroblasts. Regulations on air pollution will help reduce the global burden of allergic diseases in the future.

Huge Nasopalatine Duct Cyst Treated by Transnasal Endoscopic Marsupialization: A Case Report and Literature Review.

Nasopalatine duct cyst (NPDC) is the most common nonodontogenic cyst originating from the epithelial remnants of the incisive canal in the maxilla. NPDC is treated with complete enucleation via a sublabial or transpalatal approach, and recently tranasnasal endoscopic marsupialization has been gradually used. However, in large and extensive cases, it is difficult to remove the cyst completely, and there is a high risk of postoperative complications, including oronasal fistula. Therefore, tranasnasal endoscopic marsupialization is recommended as an effective treatment modality. Herein, we report a case of a 49-year-old man with a very large NPDC with a maximum diameter of 58 mm. NPDC was successfully managed by transnasal endoscopic marsupialization under general anesthesia without any major problems. No postoperative complications or recurrence occurred until 12 months postoperatively. Transnasal endoscopic marsupialization for large NPDC is minimally invasive and useful.

Wedge resection combined with 3D-printed polycaprolactone mesh for caudal septal deviation.

BACKGROUND: Biocompatibility and stability of three-dimensional printed polycaprolactone mesh grafts for nasal surgery are proven in both animal and human models. However, their safety and durability as batten grafts for caudal septal deviation has not been documented. This study was designed to investigate the efficacy and safety of three-dimensional printed polycaprolactone mesh batten graft in septoplasty using the wedge resection technique for the correction of caudal septal deviation. METHODS: This retrospective study reviewed the medical records of 20 patients aged ≥ 18 years with caudal septal deviation who underwent septoplasty with wedge resection and three-dimensional printed polycaprolactone mesh graft from a tertiary medical center in South Korea, between December 1, 2019 and May 31, 2021. Those without nasal obstruction before surgery or with a short follow-up period (< 28 days) were excluded from the survey analysis. RESULTS: Of the 20 patients (mean age, 48.0 [range, 19-65] years), 17 (85.0%) were male, and three (15.0%) were female. A significant change was noted in the mean nasal obstruction symptom evaluation score (68.2 vs. 15.0, P < .001) in the 17 patients included in the analysis. Postoperative endoscopic evaluation revealed a straight septum in 19/20 (95.0%) patients, and no complications were noted in the postoperative follow-up period of up to 364 days. CONCLUSIONS: The three-dimensional printed polycaprolactone nasal mesh is safe and provides adequate support to resist the intrinsic memory of the cartilage of the caudal septum. In addition to nasal surgeries, it has great potential as a graft in other reconstructive surgeries. Trial registration Retrospectively registered.

Minimally invasive sinus augmentation using ultrasonic piezoelectric vibration and hydraulic pressure: a multicenter retrospective study.

PURPOSE: The purpose of this study was to evaluate the success rate of implants and vertical bone gain of edentulous posterior maxilla using ultrasonic piezoelectric vibration and hydraulic pressure, namely the hydrodynamic piezoelectric internal sinus elevation (HPISE) technique through a crestal approach. MATERIALS AND METHODS: A total of 250 maxillary sinuses were augmented using HPISE and 353 implants (averaging 11.8 mm in length and 4.5 mm in diameter), with 12 different systems, were placed simultaneously with or without additional bone grafting. Plain radiograms and cone beam computed tomograms were taken in all patients to evaluate sinus augmentation. RESULTS: Membrane perforation was recorded at 10 of the 353 implant sites. The perforation rate was 2.83%. The total success rate of implantation was 97.2% after an average of 69.3 weeks of loading. CONCLUSION: The crestally approached sinus augmentation using ultrasonic piezoelectric vibration and hydraulic pressure is an additional method of maxillary sinus augmentation.

New bone formation in the maxillary sinus using peripheral venous blood alone.

PURPOSE: The purpose of this study was to evaluate the amount of bone formation under a sinus membrane tented with implants and filled with venous blood as a graft material. MATERIALS AND METHODS: Fourteen patients (17 sinus augmentations) were consecutively treated with sinus floor elevation via the lateral window approach. The lateral bony window was created using a piezoelectric saw, and the sinus membrane was elevated to make a new compartment. After resorbable blast media-surfaced dental implants were placed simultaneously, the collected peripheral venous blood was applied to support the sinus membrane over the implant apex, and the bony portion of the lateral window was repositioned to seal the lateral window. In 6 cases, samples were taken for biopsy at the time of second stage surgery. RESULTS: An average of 6.8 months after the sinus augmentation, new bone consolidation in the maxillary sinus was observed by radiographic and histologic evaluation. Vital bone formation was 38.70% according to the histomorphometric data. Of the 31 implants placed, 2 failed. The overall implant survival rate was 93.5%. All failures occurred when implants were placed into the extraction socket and were associated with poor initial stability. CONCLUSION: This study suggests that simultaneous placement of dental implants and injection of peripheral venous blood as a graft material appears to be a safe alternative procedure for maxillary sinus augmentation.

Bone regeneration in the maxillary sinus using an autologous fibrin-rich block with concentrated growth factors alone.

PURPOSE: The purpose of this study was to evaluate the predictability of new bone formation in the maxillary sinus using an autologous fibrin-rich blocks with concentrated growth factors (CGFs) alone as an alternative to graft material. MATERIALS AND METHODS: A total of sixty-one sinus grafts were consecutively performed using the lateral window approach. After making replaceable bony window, the sinus membrane was elevated to make a new compartment. After 113 implants (average 13 mm high) with 11 different systems were placed simultaneously, the collected fibrin-rich blocks with CGFs alone were inserted in the sinus. To seal the lateral window, the bony window was repositioned. Radiographic, clinical, and histologic evaluation was performed to verify sinus augmentation. RESULTS: No significant postoperative complications developed. New bone consolidation in all augmented maxillary sinus was observed along the implants on plain radiographs and on cone-beam computed tomograms. The success rate of implant was 98.2% after an average of 10 months loading. CONCLUSION: Fibrin-rich blocks with CGFs act as an alternative to bone grafting and can be a predictable procedure for sinus augmentation.

Comparison of two piezoelectric cutting inserts for lateral bony window osteotomy: a retrospective study of 127 consecutive sites.

PURPOSE: The aim of the present retrospective clinical study was to compare the efficacy of two piezoelectric cutting inserts for the incidence, size, and types of sinus membrane perforations, and to evaluate their various advantages for lateral window osteotomy. MATERIALS AND METHODS: The study consisted of 127 maxillary sinus augmentation procedures performed at two centers. A bony window was made on the lateral wall of the maxillary sinus with either the piezoelectric saw or the round diamond insert and repositioned over the bone graft as a homologous bony barrier. The rate of membrane perforation during sinus augmentation between the two groups was compared and analyzed statistically by the chi-square test and the two-sample t test. RESULTS: Seven perforations were seen in the 127 maxillary sinus procedures in this study (5.51%). Six perforations in 84 cases (7.14%) occurred with the piezoelectric saw and one perforation in 43 sites (2.32%) occurred while using the round insert. No statistically significant difference was found between the rates of membrane perforation between the two inserts. CONCLUSION: The lateral bony window was created effectively with either of the two kinds of piezoelectric inserts. The membrane perforation rate was not significantly affected by the type of piezoelectric insert. The piezoelectric saw insert was more advantageous than the round diamond due to its greater precision and easier repositioning of the lateral bony window as a barrier.

Immediate and delayed lateral ridge expansion technique in the atrophic posterior mandibular ridge.

PURPOSE: The lateral ridge expansion technique is used to expand the narrow edentulous ridge for implant placement. The staged approach can be used to split the mandibular ridge to decrease the risk of malfracture during osteotomy. The present study reports the clinical results of a surgical technique that expands a narrow mandibular ridge using an immediate and a delayed lateral expansion technique. MATERIALS AND METHODS: A total of 32 patients with a narrow edentulous posterior mandibular ridge of 2 to 4 mm were included in the present study, and 84 implants were placed. Of the 32 patients, 23 were treated with an immediate lateral expansion technique and 9 with a delayed lateral expansion technique. RESULTS: Of the 23 patients who underwent the immediate lateral expansion technique, a malfracture of the thin buccal cortical plate occurred during ridge splitting in 5 patients. All buccal segments of the 9 patients who underwent the delayed lateral expansion technique fractured as planned at the inferior horizontal corticotomy line favorably. After 4 to 5 months, all implants were stable and surrounded by bone, and ossification of the osteotomy line was obvious. CONCLUSIONS: The lateral ridge expansion technique is effective for horizontal augmentation in the severely atrophic posterior mandibular ridge. The delayed lateral ridge expansion technique can be used more safely and predictably in patients with high bone quality and thick cortex and a narrower ridge in the mandible.

New bone formation in the maxillary sinus using only absorbable gelatin sponge.

PURPOSE: The purpose of the present study was to evaluate the predictability of new bone formation in the maxillary sinus using only absorbable gelatin as the graft material. PATIENTS AND METHODS: Seven patients (9 sinus augmentations) were consecutively treated with sinus floor elevation by the lateral window approach. The lateral bony window was created using a piezoelectric device and the schneiderian membrane was elevated to make a new compartment. After 18 resorbable blast media surfaced dental implants were simultaneously placed, absorbable gelatin sponges were loosely inserted to support the sinus membrane over the implant apex and the bony portion of lateral window was repositioned to seal the lateral window. RESULTS: After uncovering the implants an average of 6 months after placement, new bone consolidation in the maxillary sinus was observed on radiographs without bone graft. Two implants were removed due to failed osseointegration on uncovering. Failures were caused by insufficient initial stability. CONCLUSION: This study suggests that placement of a dental implant in the maxillary sinus with a gelatin sponge can be a predictable procedure for sinus augmentation.

Reconstruction of atrophic anterior mandible using piezoelectric sandwich osteotomy: a case report.

Extensive loss of alveolar bone and teeth in the anterior mandible presents a complex problem for reconstruction. Numerous augmentation techniques are currently in use to create sufficient bone volume for reliable placement of endosseous implants in the case of severely resorbed mandibles. The aim of this report is to assess the efficacy of the piezoelectric sandwich osteotomy for vertical augmentation in the atrophic segment of anterior mandible through clinical and histologic studies. A complete osteotomized segment was made, using the piezoelectric saw, to make a segmented bone in the atrophic edentulous area and the mobile segment was elevated by 10-mm high vertically. Interpositional mineral allograft materials were inserted in the space between the basal bone and the segmented bone. A bone biopsy was performed on the augmented bone region and 3 dental implants were placed simultaneously 6 months later. About 10 mm of vertical gain was achieved by the sandwich technique. Histologic analysis presents new bone formation without inflammatory or foreign body reactions.