Alveolar Defects Research Articles

Applications of Moldable Autogenous Tooth Bone Graft (M-AutoBT) Mixed with Hydroxypropylmethyl Cellulose for Sinus Lifting

The purpose of this study is to evaluate an ability of a moldable autogenous tooth bone graft material (M-AutoBT), which is made of demineralized dentin matrix (DDM) and hydroxypropylmethyl cellulose (HPMC) to repair sinus-related defects in the implant dentistry. Sinus-related alveolar defects were classified into three types depending on the remnant of socket wall as follows; Class I: Only alveolar bone repair is required even if sinus cavity is involved (remained socket wall > 5mm). Class II: Both alveolar bone and sinus repair are required (3mm < remained socket wall < 5mm). Class III: Only sinus repair is required without any alveolar bone (remained socket wall < 3mm). Sinus cavity should always be involved during the implant placement regardless of defect types. The histological examination of three case reports, which represented class I, II and III defect respectively, showed osteoconductive and osteoinductive functions of M-AutoBT that is similar to the effect of the conventional AutoBT. Therefore, HPMC might be the suitable base material for AutoBT.

Repair of segmental bone defects in the maxilla by transport disc distraction osteogenesis: Clinical experience with a new device.

The bones of the maxillary complex are vital for normal oro-nasal function and facial cosmetics. Maxillary tumor excision results in large defects that commonly include segments of the alveolar and palatine processes, compromising eating, speech and facial appearance. Unlike the conventional approach to maxillary defect repair by vascularized bone grafting, transport disc distraction osteogenesis (TDDO) stimulates new bone by separating the healing callus, and stimulates growth of surrounding soft tissues as well. Bone formed in this way closely mimics the parent bone in form and internal structure, producing a superior anatomical, functional and cosmetic result. Historically, TDDO has been successfully used to close small horizontal cleft defects in the maxilla, not exceeding 25 mm. Fujioka et al. reported in 2012 that “no bone transporter corresponding to the (large) size of the oro-antral fistula is marketed. The authors report the successful treatment of 4 cases involving alveolar defects of between 25 mm and 80 mm in length.

Comparison of diagnostic accuracy of conventional intraoral periapical and direct digital radiographs in detecting interdental bone loss.

Periodontitis is an inflammatory disease of the supporting tissues of the teeth caused by specific microorganisms, resulting in destruction of the periodontal ligament and alveolar bone. Progressive loss of alveolar bone is the salient feature of periodontal disease. Accurate detection of periodontal disease with the use of radiographs helps in diagnosis, treatment and prognosis. The present study aims to compare the efficacy of conventional intraoral periapical (IOPA) and direct digital radiographs (RVG) in detecting interdental alveolar bone loss using intrasurgical (IS) measurements as the gold standard. Thirty patients elected to undergo periodontal flap surgery with periodontitis computing to 60 interdental alveolar defects on mandibular first molars were considered. IOPA and RVG were captured using standardized techniques. Bone loss measurements in IOPA and RVG were compared to the IS measurements. Statistical analysis was carried out using student t test and ANOVA with the help of SPSS software and p-value <0.05 was considered as significant. Both IOPA and RVG underestimated the bone loss measurements when compared to IS measurements which was statistically significant (p<0.0001). Bone loss measurements in RVG were closer to IS measurements than IOPA. Both the radiographic techniques IOPA and RVG underestimated bone loss by 1.5-2.5 mm. RVG was superior to IOPA for the detection of interdental bone loss due to reduced time and radiation exposure to obtain the same diagnostic information.

The use of autogeneous mandibular bone block grafts for reconstruction of alveolar defects.

Objective:Purpose of this retrospective study was to evaluate outcomes autogenous bone block grafts obtained from mandible for different indications. The healing of the donor and recipient sites in the postoperative period, morbidity and the resorption of the graft were investigated.Patients and Methods:Twenty-nine patients grafted with mandibular bone block graft were participated in the present study. Grafting was applied in these patients for three indications; reconstruction of alveolar cleft, lateral crest augmentation before dental implantation and sinus floor augmentation. All operations were performed under local anesthesia and in some cases sedation was used as well.Results:Minimal exposure of the block graft occurred in three alveolar cleft patients. Secondary epithelization was achieved in all cleft patients with no symptoms of infection. In one patient infection was seen in donor site 1-week after the operation. The region was curetted and antibiotics administrated again. Two patients showed an infection of recipient site, after 4 weeks the grafts were removed. In all the patients, as the screw head became apparent until 1 thread, amount of the resorption were considered <1.5 mm.Conclusion:The usage of mandibular block grafts is a simple and effective treatment modality for reconstruction of different types of alveolar defects and it also reduces cost of treatment.

A lateral ridge augmentation study toevaluate a synthetic membrane forguided bone regeneration: an experiment in the canine mandible.

To evaluate guided bone regeneration outcomes in defects protected with an in situ formed polyethylene glycol (PEG) hydrogel membrane as compared to a non-cross-linked collagen membrane (CM). Four mandibular alveolar ridge defects were created in eight hound dogs. Regenerative procedures were randomly allocated to one of four groups consisting of freeze-dried bone allograft, which is referred to in this study as freeze-dried bone xenograft (FDBX)+PEG, autogenous bone (AB)+PEG, AB+CM, and AB alone. After 8weeks, titanium dental implants were placed into augmented sites. After 8weeks of allowed time for osseointegration, the animals were sacrificed to harvest block specimens for bone-to-implant contact (BIC) and ridge width histomorphometric analysis. Polyethylene glycol membranes had an exposure rate of 50% as compared to 12.5% for sites grafted with CM. Regenerative outcomes with respect to implant placement were least favorable for FDBX+PEG which had implants placed in 37.5% of augmented sites compared to 100% implant placement for all other groups. No statistically significant differences were noted between groups for ridge width measurements in implant and non-implant histologic sections (P>0.05). Buccal BIC (%) values between treatment groups also failed to reach statistical significant difference (FDBX+PEG [60.2±9.4]; AB+PEG [58.8±8.5]; AB+CM [57.9±12.8]; AB [61.0±10.2]). When used in conjunction with FDBX, PEG had unpredictable bone formation and in most cases negatively impacted future implant placement.

A simplified technique for bridging wide alveolar cleft defects

Wider alveolar clefts/fistulae and maxillary dentoalveolar defects pose problems in achieving complete closure because of the requirement of a greater volume of bone as a graft. Segmented osteotomies have been used successfully for the repositioning of minor segments; however, in major segmented movements, the closing of the flap and the blood supply of the osteotomized segment may be compromised. Interdental distraction osteogenesis has overcome this problem by creating a segment of new alveolar bone and complete approximation of wider alveolar defects. This case report shows an effective and efficient way of distraction using a modified Hyrax appliance.

Osteogenic differentiation of human amniotic epithelial cells and its application in alveolar defect restoration.

The present study investigated the detailed in vitro osteogenic differentiation process and in vivo bone regenerative property of human amniotic epithelial cells (hAECs). The in vitro osteogenic differentiation process of hAECs was evaluated by biochemical staining, real-time polymerase chain reaction, and immunofluorescence. Next, β-tricalcium phosphate (β-TCP) scaffolds alone or loaded with hAECs were implanted into the alveolar defects of rats. Micro-computed tomography evaluation and histologic studies were conducted. Our results validated the in vitro osteogenic capacity of hAECs by upregulation of Runx2, osterix, alkaline phosphatase, collagen I, and osteopontin, with positive biochemical staining for osteoblasts. An epithelial-mesenchymal transformation process might be involved in the osteogenic differentiation of hAECs by increased expression of transforming growth factor-β1. Our data also demonstrated that in vivo implantation of hAECs loaded on β-TCP scaffolds, not only improved bone regeneration by direct participation, but also reduced the early host immune response to the scaffolds. The presented data indicate that hAECs possess proper osteogenic differentiation potential and a modulatory influence on the early tissue remodeling process, making these cells a potential source of progenitor cells for clinical restoration of the alveolar defect.

Alveolar ridge reconstruction with titanium mesh: a three-dimensional evaluation of factors affecting bone augmentation.

To evaluate the three-dimensional (3D) reconstruction of atrophic alveolar ridges using titanium mesh (Ti-mesh) and its correlation with the extent and timing of mesh exposure and amount of reconstruction planned. This study retrospectively evaluated 12 patients (mean age, 49.1 years) with 15 alveolar defects treated with Ti-mesh and particulate grafts (70/30 autogenous bone/anorganic bovine bone) followed by implant placement 8 to 9 months later. For each site, computed tomography images were analyzed using software designed to measure 3D volumes. The lacking bone volume (LBV) was calculated by subtracting the reconstructed bone volume at reentry from the planned bone volume (PBV). In all cases, the meshes were modeled preoperatively on a stereolithographic model. LBV was correlated with the extent and time of mesh exposure and PBV. The mean LBV (0.45 cm3) was 30.2% (range, 6% to 74%) of the mean PBV (1.49 cm3). The mean extent and timing of mesh exposure, which occurred at 80% of augmented sites (12/15), were 0.73 cm2 (range, 0.09 to 3.45 cm2) and 2.17 months (range, 1 to 8 months), respectively. LBV was significantly positively correlated with the area of mesh exposed, with 16.3% LBV for every cm2 of mesh exposed; there were positive correlations between LBV and early exposure and PBV. On average, there was 30.2% less bone than planned preoperatively; there was a significant negative correlation between the amount of reconstructed bone and area of mesh exposed.

The vascularized sural nerve graft based on a peroneal artery perforator for reconstruction of the inferior alveolar nerve defect

The sural nerve has been described for nerve reconstruction of the maxillofacial region since it provides many advantages. We report a case of a vascularized sural nerve graft based on a peroneal artery perforator for immediate reconstruction after the removal of intraosseous neuroma originating in the inferior alveolar nerve. The patient had a neuroma caused by iatrogenic injury to the inferior alveolar nerve. A 4-cm long neuroma existed in the inferior alveolar nerve and was resected. A peroneal perforator was chosen as the pedicle of the vascularized sural nerve graft for the nerve gap. The graft including the skin paddle for monitoring the perfusion supplied by this perforator was transferred to the lesion. The nerve gap between the two stumps of the inferior alveolar nerve was repaired using the 6-cm long vascularized sural nerve. The perforator of the peroneal artery was anastomosed to the branch of the facial artery in a perforator-to-perforator fashion. There was no need to sacrifice any main arteries. The skin paddle with 1 cm × 3 cm in size was inset into the incised medial neck. Perceptual function tests with a Semmes-Weinstein pressure esthesiometer and two-point discrimination in the lower lip and chin at 10 months after surgery showed recovery almost to the level of the normal side. This free vascularized sural nerve graft based on a peroneal artery perforator may be a good alternative for reconstruction of inferior alveolar nerve defects.

The study of bone repair effect of recombinant human bone morphogenetic protein-2 combined with artificial bone substitute materials in alveolar defect around the dental implant

Objective To evaluate the bone repair capacity of β-tricalciumphosphate (β-TCP) or Bio-Oss combined with recombinant human bone morphogenetic protein-2 (rhBMP-2) in Beagle dogs.Methods Ten healthy adult Beagle dogs were used in this study.The mandibular premolars of the dogs were extracted firstly.Three months later,dental implants were placed in the mandibular,and a 5 mm× 4 mm× 3 mm bone defect area was prepared on the buccal side of each implant.The bone defect areas were filled with β-TCP,rhBMP-2/β-TCP compound,Bio-Oss or rhBMP-2/Bio-Oss compound respectively.The bone defect areas were filled nothing as the blank.The dogs were sacrificed after 4 or 12 weeks.Samples were prepared for the gross observation,X-ray analysis and histomorphology analysis.Results The new bone formation was observed in all experiment groups.After 4 weeks,the bone density of materials combined with rhBMP-2 groups [(36.70 ± 1.73) ％ and (38.50 ± 1.83) ％] were higher than the raw materials groups [(30.50 ± 1.81)％ and (31.48 ± 1.86)％].After 12 weeks,the bone density of materials combined with rhBMP-2 groups [(52.84 ± 1.85) ％ and (54.85 ± 1.87) ％] were also higher than the raw materials groups [(43.65 ± 1.81) ％ and (44.94 ± 1.88) ％].And new bone formation rate of the materials combined with rhBMP-2 groups were higher than the raw materials groups at each evaluation time.Conclusion rhBMP-2 can promote the bone regeneration activity of the artificial bone substitute materials effectively. Key words: Bone morphogenetic protein; Artificial bone substitute materials; Bone defect

Bilateral Alveolar Distraction for Large Alveolar Defects: Case Report.

Distraction osteogenesis has become a very popular technique, as the ability to reconstruct combined deficiencies in bone and soft tissue makes this process unique and invaluable to all types of reconstructive surgeons. We document a case in which an intraoral tooth-borne distractor was designed and segmental alveolar distraction was performed in a large alveolar defect in a patient with bilateral cleft lip and palate. Cosmetic dentistry was performed to attain a pleasing result. This article aims at highlighting the use of distraction in large defects in which bone grafting only is not a suitable procedure.

Health in Ancient Mariana Islanders: A Bioarchaeological Perspective

ABSTRACTPrevious investigation of health and lifestyle in the Mariana Islands indicated that the prehistoric inhabitants living on the smaller islands of this archipelago experienced more stress than those living on the larger islands. This article expands on previous research by using one of the largest datasets (N = 385) now available for examining the health of prehistoric skeletons from the Mariana Islands. A total of 13 indicators of health are investigated, including cribra orbitalia, linear enamel hypoplasia, stature, trauma, infection, and dental disease. There is considerable inter-island variability for many of the indicators but, in general, the highest frequencies of stress are often associated with skeletons from the smaller islands. The sole exception is Rota, the smallest island that reveals levels of stress similar to Guam, the largest island. For several indicators (e.g., stature, long bone fracture, spondylolysis, alveolar defect) there were no significant differences among islands. Cultural habits such as chewing areca (betel) nut, environmental factors, and other cultural differences are examined to explain these differences.

Horizontal bone augmentation by means of guided bone regeneration.

The development of bone augmentation procedures has allowed placement of dental implants into jaw bone areas lacking an amount of bone sufficient for standard implant placement. Thus, the indications for implants have broadened to include jaw regions with bone defects and those with a bone anatomy that is unfavorable for implant anchorage. Of the different techniques, the best documented and the most widely used method to augment bone in localized alveolar defects is guided bone regeneration. A large body of evidence has demonstrated the successful use of guided bone regeneration to regenerate missing bone at implant sites with insufficient bone volume and the long-term success of implants placed simultaneously with, or after, guided bone regeneration. However, the influence of guided bone regeneration on implant survival and success rates, and the long-term stability of the augmented bone, remain unknown. Many of the materials and techniques currently available for bone regeneration of alveolar ridge defects were developed many years ago. Recently, various new materials and techniques have been introduced. Many of them have, however, not been sufficiently documented in clinical studies. The aim of this review was to present the scientific basis of guided bone regeneration and the accepted clinical procedures. A classification of bone defects has been presented, aiming at simplifying the decision-making process regarding the choice of strategy for bone augmentation. Finally, an outlook into actual research and the possible future options related to bone augmentation has been provided.

RhBMP-2 in the Reconstruction of Alveolar Clefts as an Alternative to Autologous Grafting

Background: Secondary alveolar cleft reconstruction using autologous anterior iliac crest (AIC) is currently the gold standard treatment. Although highly predictable and successful, this additional surgical site is associated with considerable, although rare, donor site morbidities including significant postoperative pain, potential for infection, as well as gait and neurosensory disturbances. In an effort to minimize the morbidities associated with autologous graft surgery, a variety of grafting alternatives have been explored, including the use of recombinant human bonemorphogenetic protein (rhBMP-2) on an absorbable collagen sponge (ACS). Bone morphogenetic protein is an osteogenic growth factor essential for embryologic development and formation of the skeleton. Minute quantities of these proteins are contained in the mature skeleton and are involved in bone healing and remodeling throughout life. When administered at a supraphysiologic level, bone morphogenic protein is found to be a potent inducer of de novo bone generation. INFUSE (Medtronic, Minneapolis, MN) is FDA approved for certain spinal fusion and maxillofacial procedures. In recent years, off-label use for alveolar cleft repair in pediatric patients has shown to be an effective and feasible alternative technique in the reconstruction of alveolar cleft defects. Methods: A chart review was conducted of 8 patients whounderwent secondary alveolar cleft reconstructionusing INFUSE (rhBMP-2/ACS) by a single surgeon (DCH). 3 females and 5 males were identified with age at time of treatment ranging from 7 to 13 years and an average age of 9.8 years. Of the 8 patients, 6 had unilateral alveolar cleft defects and 2 had a bilateral defects repairedwith a total of 10 sites grafted. Post-operative i-CAT (Imaging Sciences International, LLC, Hatfield, PA) cone beam CT scans were taken at aminimumof sixmonths following graftingprocedures to assess success of bone formation at the alveolar cleft. Success was measured by evaluating bone height fromnasal floor to alveolar crest,width, bone density using Hounsfield unit (HU), and radiographic evidence of bony continuity.

Reconstruction of maxillary ridge atrophy caused by dentoalveolar trauma, using autogenous block bone graft harvested from chin: a case report

Background Dentoalveolar trauma, especially when involving front teeth, negatively affect the patient’s life; in particular, tooth avulsion is a complex injury that affects multiple tissues, and no treatment option offers stable long-term outcomes. The aim of this study was to report a case of reconstruction of atrophic anterior alveolar ridge after tooth loss, performed with autograft harvested from the chin, and subsequent prosthetic rehabilitation with the use of an osseointegrated implant. Case report A 23-years-old Caucasian girl, presented an atrophic alveolar bone in the area of tooth 11, as a result of tooth resorption 10 years after a tooth reimplantation procedure. Reconstruction was performed with autogenous bone harvested from the chin. After 6-months healing period to allow autograft incorporation, a dental implant was inserted. After further 6- months, a screw-retained implant supported metal-ceramic prosthesis was fabricated. Results The prosthetic rehabilitation was successful, and after a follow-up period of 5 years, the achieved result was stable. Conclusion It can be concluded that the autogenous bone graft harvested from the chin, is a safe and effective option for alveolar ridge defects reconstruction, allowing a subsequent placement of a dental implant supporting a prosthetic restoration.

Scanning Electron Microscopy and Energy Dispersive X-ray Spectroscopy Studies on Processed Tooth Graft Material by Vacuum-ultrasonic Acceleration.

Purpose:The current gold standard for clinical jawbone formation involves autogenous bone as a graft material. In addition, demineralized dentin can be an effective graft material. Although demineralized dentin readily induces heterotopic bone formation, conventional decalcification takes three to five days, so, immediate bone grafting after extraction is impossible. This study evaluated the effect of vacuum ultrasonic power on the demineralization and processing of autogenous tooth material and documented the clinical results of rapidly processed autogenous demineralized dentin (ADD) in an alveolar defects patient.Methods:The method involves the demineralization of extracted teeth with detached soft tissues and pulp in 0.6 N HCl for 90 minutes using a heat controlled vacuum-ultrasonic accelerator. The characteristics of processed teeth were evaluated by scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS). Bone grafting using ADD was performed for narrow ridges augmentation in the mandibular area.Results:The new processing method was completed within two hours regardless of form (powder or block). EDS and SEM uniformly demineralized autotooth biomaterial. After six months, bone remodeling was observed in augmented sites and histological examination showed that ADD particles were well united with new bone. No unusual complications were encountered.Conclusion:This study demonstrates the possibility of preparing autogenous tooth graft materials within two hours, allowing immediate one-day grafting after extraction.

Cranial bone grafting for alveolar clefts: a 25-year review of outcomes.

Cranial bone grafting for an alveolar cleft obtains membranous bone from a low-morbidity donor site. Although iliac crest bone is the favored donor site, there are no objective analyses of three-dimensional radiologic outcomes with cranial bone grafting and no studies evaluating complications and long-term outcomes in a large series of patients undergoing cranial bone grafting. A retrospective chart review was conducted on patients who underwent alveolar bone grafting from the cranium over a 25-year period performed by a single surgeon. Data collected included patient characteristics, complications, and clinical outcomes. Radiologic analysis of graft outcomes was determined using Amira volume-rendering software on the most recent 10 consecutive patients. The authors' study cohort included 308 patients, with an average age of 11.5 years. Complications involved harvesting the graft in 3.5 percent, the donor site in 1 percent, and the recipient site in 17.2 percent. Regrafting was required in 7.1 percent, with a clinical success rate of 92.9 percent. The average alveolar defect was 1.19 ml preoperatively and 0.19 ml postoperatively, with 85 percent fill of the cleft defect by radiologic analysis. Cranial bone grafting for the alveolar cleft is a low-morbidity operation and has success similar to that of iliac crest bone grafting. It should be considered more often as a viable option for the alveolar cleft patient. Therapeutic, IV.

Specific activation of K-RasG12D allele in the bladder urothelium results in lung alveolar and vascular defects.

K-ras is essential for embryogenesis and its mutations are involved in human developmental syndromes and cancer. To determine the consequences of K-ras activation in urothelium, we used uroplakin-II (UPK II) promoter driven Cre recombinase mice and generated mice with mutated KrasG12D allele in the urothelium (UPK II-Cre;LSL-K-rasG12D). The UPK II-Cre;LSL-K-rasG12D mice died neonatally due to lung morphogenesis defects consisting of simplification with enlargement of terminal air spaces and dysmorphic pulmonary vasculature. A significant alteration in epithelial and vascular basement membranes, together with fragmentation of laminin, points to extracellular matrix degradation as the causative mechanism of alveolar and vascular defects. Our data also suggest that altered protease activity in amniotic fluid might be associated with matrix defects in lung of UPK II-Cre;LSL-K-rasG12. These defects resemble those observed in early stage human neonatal bronchopulmonary dysplasia (BPD), although the relevance of this new mouse model for BPD study needs further investigation.

The Importance of Immediate Bone Block Autograft to Successfully Restore the Function and Aesthetic of the Anterior Alveolar Process and Teeth

Maxillofacial traumatic injuries can damage the jaw, teeth, and soft tissues of the head and neck region. When these injuries occur, best practice is to reconstruct as comprehensively as is clinically prudent at time of injury. Smart and efficient procedures during the initial surgery can minimize subsequent reconstructive procedures in scope and number, minimize expense, and result in a better final aesthetic and functional outcome. Restoration of anterior alveolar jaw fractures with comminuted or avulsed segments becomes a complex prospect when left untreated after initial trauma or injury and can result in alveolar ridge defects that are difficult, costly, and cumbersome to repair. This case report details one 19-year-old woman who had a traumatic injury in these areas and has a best result outcome because of immediate reconstruction efforts involving a bone block autograft to preserve alveolar process anatomy.

Timing of force application affects the rate of tooth movement into surgical alveolar defects with grafts in beagles

The purpose of this study was to investigate the influence of the timing of orthodontic force application on the rates of orthodontic tooth movement into surgical alveolar defects with bone grafts in beagle dogs. Twelve beagles were randomly divided into 2 groups according to the surgical procedure: alveolar osteotomy alone (control) or osteotomy with bone graft (experimental group). The maxillary second premolars were protracted for 6 weeks into the surgical sites: immediately, at 2 weeks, and at 12 weeks after surgery. The orthodontic tooth movement rates and alveolar remodeling concomitant with surgical defect healing were evaluated by model measurements and histomorphometry as well as microcomputed tomography and histology. One-way analysis of variance and the Scheffé post hoc comparison were performed for investigating the rates of orthodontic tooth movement and mineralized bone formation. Both the orthodontic tooth movement rate and the mean appositional length of mineralized bone in the tension side of teeth were significantly accelerated when force was applied at 2 weeks in the control group and immediately in the experimental group (P<0.001). The 2-week control group showed a dramatic increase in apposition rate during 4 to 6 weeks after force application, whereas the immediate protraction experimental group did within the first 3 weeks (P<0.001). Decreased orthodontic tooth movement rates and reduced bone remodeling activities were apparent in the 12-weeks groups, especially in nongrafted defects. A bone graft into the surgical defect can not only allow immediate force application for accelerating orthodontic tooth movement with favorable periodontal regeneration, but also decrease the risk of inhibited orthodontic tooth movement in case of delayed force application after surgery.