Alveolar Defects Research Articles

Dehiscence and fenestration in skeletal Class I, II, and III malocclusions assessed with cone-beam computed tomography

To test the null hypothesis that the presence of dehiscence and fenestration was not different among patients with skeletal Class I, II, and III malocclusions. In this retrospective study, a total of 123 cone-beam computed tomography (CBCT) images were obtained with an iCAT scanner (Imaging Sciences International, Hatfield, Pa). Patients with normal vertical patterns were classified according to dental malocclusion and ANB angle. Class I comprised 41 patients-21 girls and 20 boys (mean age, 22.4 ± 4.5 years); Class II comprised 42 patients-22 girls and 20 boys (mean age, 21.5 ± 4.2 years); and Class III comprised 40 subjects-22 girls and 18 boys (mean age, 22.1 ± 4.5 years). A total of 3444 teeth were evaluated. Analysis of variance and Tukey's test were used for statistical comparisons at the P < .05 level. Statistical analysis indicated that the Class II group had a greater prevalence of fenestration than the other groups (P < .001). No difference was found in the prevalence of dehiscence among the three groups. Although fenestration had greater prevalence in the maxilla, more dehiscence was found in the mandible for all groups. In Class I, alveolar defects (dehiscence, fenestration) were matched relatively in both jaws. Furthermore, Class II and Class III subjects had more alveolar defects (41.11% and 45.02%, respectively) in the mandible. Dehiscences were seen with greater frequency in the mandibular incisors of all groups. The null hypothesis was rejected. Significant differences in the presence of fenestration were found among subjects with skeletal Class I, Class II, and Class III malocclusions. Fenestrations had greater prevalence in the maxilla, but more dehiscences were found in the mandible.

A New Device for Alveolar Bone Transportation

We present a retrospective review of a new technique for the transportation of alveolar bone using a Hyrax device modified by the principal author (O.A.V.). There were seven patients (five males and two females), including five patients with cleft palate and lip diagnosis, one patient with a high-speed gunshot wound, and one patient with facial trauma sequel due to mandibular fracture. They were all treated with an alveolar bone transportation technique (ABT) through the use of the modified Hyrax device (VEGAX). Before surgery, distraction osteogenesis of the bifocal type was performed on four patients, and the trifocal type was performed on the other three patients. However, in one case, direct dental anchorage was not used, only orthodontic appliances. In all the cases, new bone formation and gingival tissue around the defect were obtained, posterior to the alveolar distraction process; no complications were observed in any patient. In one case, two teeth involved in the disk of the ABT were extracted, due to a previous condition of periodontal disease. The alveolar bone transport with the VEGAX device is an accessible technique for almost every patient with alveolar defects due to diverse causes. In all the presented cases, predictability and success were demonstrated.

Modified Presurgical Nasoalveolar Molding in the Infants with Complete Unilateral Cleft Lip and Palate: A Stepwise Approach

Presurgical orthopedics in one or the other form has been an important part of the multidisciplinary approach towards the better cleft care. Presurgical nasoalveolar molding (PNAM) was described as a modified approach to the conventional form of orthopedics. PNAM not only reduces the severity of the alveolar defect before surgery, it also reduces the nasal deformity bringing it near to the normal. Nonsurgical nasal correction forms an important adjunct to the primary nasal repair at the time of primary lip repair. However, acceptance of nasoalveolar molding in Indian set-up has not been wide spread due to various reasons such as lack of the resources and inability of the parents to comply with the frequent adjustment schedule. At the Nitte Meenakshi Institute of Craniofacial surgery at the Nitte University, Mangalore, authors have developed a modification of the PNAM appliance previously described in the literature. The key modification is done at the time of fabrication of the occlusal prosthesis. This modification has made the overall procedure simpler and at the same time helped to reduce the recall visits by half of the originally required. This article describes the fabrication procedure of the modified nasal alveolar molding appliance and the modified treatment protocol in a stepwise manner.

Use of Cone Beam Computed Tomography to Volumetrically Assess Alveolar Cleft Defects—Preliminary Results

The purpose of this study was to determine the utility of cone beam computed tomographic (CBCT) imaging in assessing the volume of alveolar cleft defects in patients undergoing secondary cleft repair. Fourteen patients with unilateral clefts were analyzed in a retrospective study. Preoperative CBCT imaging of patients preparing to undergo secondary repair of alveolar clefts was reviewed. Using anatomic landmarks, 3 measurements were collected from CBCT images for each patient: facial width (FW), facial height (FH), and facial-palatal length (FL). These values were used to calculate the estimated volume (EV) of the cleft and thus the amount of bone graft material that would be needed to fill the defect. The overall mean values of FW, FH, and FL were 9.7 ± 3.1, 14.07 ± 2.7, and 5.6 ± 0.8 mm, respectively. Mean EV was 489.0 ± 151.6 mm(3). The single (0.879) and average (0.956) measurements of the intraclass correlation coefficient for FH were very good to excellent. Similar data were observed for FH (single, 0.827; average, 0.935). For FL, a decreasing trend in the mean and variability over the 3 measurement times was reflected in low single (0.305) and moderate average (0.569) intraclass correlation coefficients. CBCT imaging can be used to reliably measure FW, FH, and FL and to calculate the EV of the cleft. These data can be used by oral and maxillofacial surgeons to quantitatively assess the volume of an alveolar cleft and aid in preoperative determination of the amount of bone that will be needed to adequately graft the cleft space. This will also aid in appropriate selection of an autogenous graft donor site before surgery.

Tertiary bone grafting using calvarial bone transplants in patients with cleft lip and alveolus

AbstractTertiary osteoplasty of alveolar cleft defects is often necessary in patients where bone resorption after secondary osteoplasty leads to an insufficient amount of bone of the alveolar crest. In most of the cases, the permanent tooth of the cleft area is missing and needs to be restored with an implant. Because of an insufficient bony support, tertiary bone grafting prior to implant insertion is necessary. Three cases of tertiary osteoplasty of alveolar cleft defects are presented. Good clinical results and low graft resorption of calvarial bone grafts after tertiary osteoplasty in patients with cleft lip and alveolus let us presume that these kinds of grafts are a promising alternative to iliac bone transplants.

Foxn4 influences alveologenesis during lung development

The terminal stage of lung development begins with the formation of the terminal sacs followed by subdivision of these sacs by septa into numerous alveoli to maximize the gas-exchange surface. This process requires coordinated action of various intrinsic and extrinsic factors as well as interaction of epithelial and mesenchymal cells. We show here that during murine lung development, the Foxn4 transcription factor is expressed in proximal airways by a subpopulation of postmitotic epithelial cells which are distinct from basal and ciliated cells and of which only a small fraction are Clara cells. Targeted inactivation of Foxn4 causes dilated alveoli, thinned alveolar walls, and reduced septa in the distal lung but no overt gross alterations in proximal airways. The alveolar defects in mutants may result from decreased platelet-derived growth factor-A (PDGFA) signaling and reduced surfactant protein B (SFTPB) expression. These data together suggest that Foxn4 may have a non-cell-autonomous role critical for alveologenesis during lung development.

Repair of alveolar cleft defect with mesenchymal stem cells and platelet derived growth factors: A preliminary report

The purpose of this study was to evaluate the enhancing effect of recombinant platelet derived growth factor on human mesenchymal stem cells (hMSCs) in secondary alveoloplasty. Three patients with 4 alveolar defects were selected for this study. Mesenchymal stem cells were cultured from a posterior iliac bone aspirate. MSCs were mounted on biphasic scaffolds and combined with platelet derived growth factor (PDGF) in the operating room to make a triad of the scaffold, growth factor, and cells. The triads were placed in anterior maxillary cleft defects and closed with lateral advancement gingival flaps. The postoperative cleft bone volume was measured with cone beam computed tomography scans. A mean of 51.3% fill of the bone defect was calculated 3 months post-operation. Our data suggests the use of recombinant platelet derived growth factor with hMSCs may enhance the regeneration capacity of the cells.

Combined bony closure of oroantral fistula and sinus lift with mandibular bone grafts for subsequent dental implant placement

Sinus lifting and reconstruction of localized alveolar defects are often required after closure of a large oroantral fistula (OAF) to allow for subsequent implant installation. This study describes a combined surgical technique that involves sinus lifting, bony closure, and reconstruction of the alveolar defect at the site of an OAF. The sinus membrane was reconstructed as a continuous layer by combining the residual sinus membrane with a rotated part of oral mucosa around the OAF. Autogenous bone from the chin and/or ramus was grafted into the prepared sinus space and alveolar defect, and the graft was covered by a buccal advancement flap. This technique was used to treat 8 patients who had large OAFs in the posterior maxillary region. The treatment was successful in all cases, and the technique appears to be suitable for large OAFs where implants are subsequently desired.

Orthodontic Tooth Movement in Alveolar Cleft Repaired with a Tissue Engineering Bone: An Experimental Study in Dogs

Tissue engineering approaches have been successfully used in repairing bone defects and have become a viable alternative to autologous bone. The aim of the present study was to investigate if a construct of porous beta-tricalcium phosphate (β-TCP) combined with osteogenically induced bone marrow stromal cells (bMSCs) could repair alveolar cleft, and allow for subsequent orthodontic tooth movement in a canine model. Twelve alveolar osteotomy surgeries in six animals were made bilaterally and randomly implanted by (1) tissue-engineered bone complex of bMSCs/β-TCP (group A, n=4), (2) β-TCP alone (group B, n=4), and (3) autologous bone obtained from iliac bone (group C, n=4). Contralateral alveolar defects were created in one animal and left untreated to serve as blank control to observe spontaneous healing of the defects. Sequential fluorescent labeling and radiographic observation was used to evaluate new bone formation and mineralization in each defect. Orthodontic tooth movement was initiated 8 weeks after surgical operation for 12 weeks, and then the dogs were sacrificed for histological and histomorphometric analysis. Results indicated that the tissue-engineered complex with bMSCs/β-TCP dramatically promoted new bone formation and mineralization and achieved a favorable height of the repaired alveolar when compared with β-TCP alone, which absorbed severely. The overall effect of the tissue-engineered bone was equivalent to autologous bone; the physiological function of the alveolar bone was restored by allowing the adjacent teeth to move into the newly formed bone in the grafted region. This study demonstrated that the tissue engineering bone from the combination of β-TCP and bMSCs is a feasible clinical approach for patients with alveolar cleft and the subsequent orthodontic tooth movement.

Mandibular Alveolar Bony Defect Repair Using Bone Morphogenetic Protein 2-Expressing Autologous Mesenchymal Stem Cells

Mandibular bone regeneration is stepped up by human recombinant bone morphogenetic protein 2 (BMP-2) whose application is also related to limited cementum and periodontal ligament regeneration, local root resorption, and ankylosis. The alveolar bone grafting without traditional autologous bone grafts remains a challenge for plastic surgeons. Bilateral mandibular alveolar and periodontal defects were created over the premolar areas in 9 mature male beagles. The defects were randomly assigned for either the adenovirus BMP-2 (advBMP-2) group with BMP-2-expressing mesenchymal stem cells (MSCs) or the control with MSCs alone. The regenerated periodontal attachment apparatus was evaluated histologically, and the whole regenerated bone volume was scrutinized from three-dimensional computed tomography analysis. Periodontal apparatus regeneration was significantly better in the advBMP-2 group. New cementum and Sharpey fibers were observed on the denuded root surfaces in the advBMP-2 group, whereas incomplete healing with localized root surface resorption was noted in the control group. Eight weeks after implantation, the advBMP-2 group showed significant increase in bone regeneration than the control one. Thus, the use of ex vivo BMP-2-engineered autologous MSCs boosted bone and periodontal apparatus regeneration in mandibular periodontal defects. This de novo approach might be suitable for clinical mandibular bone repair and periodontal apparatus repair.

Development of a chitosan–polyglutamate based injectable polyelectrolyte complex scaffold

In this study, the chitosan–polyglutamate hydrogel was developed as injectable polyelectrolyte complex (PEC) scaffold for bone regeneration. In practice, oppositely charged polyelectrolytes were mixed using a static injection mixer, the gelation time was less than 1 min. The resorbable PEC scaffold can be in situ-formed as a scaffold for osteoblast ingrowth. The canine alveolar defect model was used to evaluate the efficacy of PEC implants. The PEC scaffold was highly effective in enhancing bone regeneration. Moreover, the addition of CaSO 4·2H 2O (CSD) to PEC scaffold can further enhance the early stage healing of bone regeneration.

Alveolar cleft defect closure with iliac bone graft, rhBMP-2 and rhBMP-2 with zygoma shavings: Comparative study

Aim:To present the outcome measures of the use of iliac bone graft, rhBMP-2 and rhBMP-2 with zygoma shavings in alveolar cleft defect closure.Materials and Methods:Retrospective analysis of details of treated alveolar defect cases (5-10 years during January 2008–December 2010) from records with 4 months follow-up in accordance with the inclusion criteria.Predictor Variables:Type of graft used (iliac crest graft/rhBMP-2/rhBMP-2 with zygoma shaving).Outcome Variables:Duration of the operation, blood loss, postoperative drugs used, donor site morbidity, efficiency of bone deposition (radiologically) at 4 months.Statistics:Descriptive statistics, one-way ANOVA. P < 0.05 was taken as significant.Results:Forty two cases met the inclusion criteria. Mean efficiency of bone deposition was 89.97 ± 4.79%. Mean efficiency of bone formation in rhBMP-2 (n=13), rhBMP-2 with zygoma shavings (n=9) and iliac crest graft (n=20) was 89.42%, 95.38% and 87.91%, respectively (P=0.000). Drugs usage and postoperative morbidity differed significantly between groups (P < 0.05).Conclusion:The use of rhBMP-2 evades the need for additional surgery and overcomes the postoperative morbidity that is associated with the conventional iliac grafting technique. The rhBMP-2 with zygoma shavings showed maximum benefits.

Rehabilitation of recurrent unicystic ameloblastoma using distraction osteogenesis and dental implants

Ameloblastoma is a true neoplasm of odontogenic epithelial origin. Surgical resection of the ameloblastoma is well-documented and an accepted treatment modality. Vertical distraction of the alveolar process is an efficient method for augmentation. This method of providing additional bone and soft tissue for implant placement is becoming more common. This clinical report describes the use of distraction osteogenesis and fixed implant supported prosthesis to treat a post-surgical alveolar defect as a result of the resection of a unicystic ameloblastoma in the anterior mandibular region. As a result of alveolar distraction a segment of mature bone was transported vertically in order to lengthen the crest, for better implant anchorage. Further clinical and experimental studies of the technique with long-term follow-up are needed, to confirm bone and implant stability, as it relates to alveolar height.

Clinicoradiographic Evaluation and Feasibility of Dental Implant in Infected Dentoalveolar Socket

Purpose: To describe a protocol for immediate placement of endosseous implant into debrided infected dentoalveolar socket.Patients and methods: A total of 21 implants were placed in 10 patients. The immediate placement protocol emphasized the meticulousdebridement of the infected tissue in combination with periapical ostectomy of socket. Guided bone regeneration was accomplished tosupport bony healing of alveolar defects surrounding implantation site. Pre- and postsurgical antibiotic therapy was administered.Results: All implants, but one, were osseointegrated after 6 months follow-up and were functional 6 months postoperatively. One implantwas mobile on exposure after 6 months and was removed.Conclusion: Successful immediate implantation in debrided infected alveolus depends on complete removal of all contaminated tissueand the controlled regeneration of alveolar defect.

Reconstruction of Posterior Mandibular Alveolar Ridge Deficiencies With the Piezoelectric Hinge–Assisted Ridge Split Technique: A Retrospective Observational Report

Reconstruction of alveolar defects in the posterior edentulous mandible can be a difficult task. In addition to complicating anatomic features, such as the inferior alveolar nerve, mental foramen, oblique ridge, and lingual undercut of the mylohyoid ridge, edentulous ridges in the posterior mandible have thicker cortices and decreased volumes of vascular trabecular bone than their maxillary counterparts. Traditionally, these areas have been treated with autogenous block grafts. Significant resorption of these grafts, in combination with patient morbidity at secondary donor sites, has led clinicians to seek alternatives for augmenting the edentulous posterior mandible. The aim of this retrospective consecutive case series is to report on both the technique of the piezoelectric hinge-assisted ridge split procedure for augmenting these sites and the results that were achieved. Thirteen patients with 17 horizontal alveolar ridge deficiencies of the posterior mandible were treated with the piezoelectric hinge-assisted ridge split procedure. After an average healing period of 14 weeks, dental implants were placed into the augmented sites. Intrasurgical alveolar ridge measurements taken at the initial surgery and subsequently at the time of implant placement documented the horizontal gains achieved by this procedure. Overall mean gain in horizontal width was 4.03 mm (± 0.67). For single implant-site augmentations, the mean gain was 3.38 mm (± 0.25). For multiple adjacent implant-site augmentations, mean gain was 4.25 mm (± 0.62). A total of 31 dental implants were successfully placed in all sites and none required additional augmentation procedures. There were no instances of adverse outcomes, such as neurosensory deficits or sequestration of mobilized buccal plates. After a minimum of 6 months of loading, all dental implants have been successful. This retrospective observational report demonstrates that the piezoelectric hinge-assisted ridge split procedure can achieve substantial gains in horizontal ridge width of the edentulous posterior mandible without associated morbidity. Further prospective and larger observational studies are warranted to see if this is true over a larger patient population and to compare this technique to other more traditionally used approaches.

Detection of lip, alveolar ridge and hard palate abnormalities using two‐dimensional ultrasound enhanced with the three‐dimensional reverse‐face view

The aim of this study was to assess conventional two-dimensional (2D) ultrasound enhanced with a three-dimensional (3D) ultrasound technique, the 'reverse-face' view (3D-RF) in prenatal evaluation of the involvement of the lips, alveolar ridge and secondary palate in suspected isolated orofacial clefting. One hundred and twenty-four cases of suspected orofacial clefting diagnosed by a routine 2D ultrasound scan were referred for specialist ultrasound at 20-34 weeks' gestation for a detailed assessment of the lips and palate using both 2D and 3D ultrasound. For the 3D examination the lips and alveolar ridges were examined both in profile and in the frontal plane. The palate was then assessed in the reverse coronal view by rotating the face through 180° on the vertical axis to produce the 3D-RF view. Antenatal diagnoses were compared with postnatal findings. Left and right lip and alveolar ridge defects were counted separately according to the Kernohan 'striped Y' classification. Of 124 patients, 110 had isolated facial clefts and were available for follow-up; in 10, 3D-RF views were not successfully obtained, leaving 100 cases for assessment. The sensitivity of the 2D enhanced with 3D-RF technique for the diagnosis of cleft of the lip was 116/122 (95%), false-positive rate (FPR) 7.7%; for alveolar ridge was 87/103 (84.5%), FPR 7.2%; and for hard palate was 61/68 (89.7%), FPR 15.6%. The data reported represent the largest series of orofacial abnormalities diagnosed by 2D ultrasound and enhanced with 3D imaging to refine the detection of clefts of the hard palate. The technique is feasible in 90% of patients in whom almost 90% have a correct classification of clefts of the lip, alveolar ridge and palate.

Histomorphometric analysis of different latency periods effect on new bone obtained by periosteal distraction: an experimental study in the rabbit model

The aim of this study was to evaluate the effects of latency period on the bone formation after periosteal distraction. For this purpose, a rabbit model was developed and histologic and histomorphometric analyses were conducted. Periosteal distractors were custom designed and built from stainless steel. Rabbits were divided into 2 groups of 18 each according to the duration of latency period. In group 1, the latency period was 7 days, and in group 2 it was 1 day. Distraction was performed by activating the distractor 0.25 mm twice per day. A periosteal distraction of 7.0 mm was achieved after a distraction period of 10 days. Both groups were divided to 3 subgroups according to the rabbits being killed on the 15th, 30th, or 60th day of the consolidation period. Histologic and histomorphometric analyses were performed to evaluate the bone formation. In the histologic evaluation, new bone formation was observed on the lateral side of the mandible of all the rabbits. Histomorphometric measurements revealed that the mean area of newly formed bone formation was 2.62 cm(2) in group 1 and 3.26 cm(2) in group 2. Periosteal distraction osteogenesis is a viable method in acquired and congenital alveolar ridge defects, resulting in new bone formation. Newly formed bone can be obtained by periosteal distraction osteogenesis applying different latency periods.

Comparative study of the osseointegration of dental implants after different bone augmentation techniques: vascularized femur flap, non-vascularized femur graft and mandibular bone graft

The purpose of this study was to evaluate the osseointegration of the dental implants placed into the mandible augmented with different techniques in pigs. Four adult domestic pigs were used. Horizontal augmentation of the mandible was performed in animals by using vascularized femur flap (VFF), non-vascularized femur graft (NVFG) and monocortical mandibular block graft (MG). After 5 months of healing 10 dental implants were placed into each augmented site. The pigs were sacrificed after 3 months of healing. Undecalcified sections were prepared for histomorphometric analysis. Mean bone-implant contact (BIC) values for implants placed into MG, NVFG and VFF were 57.38 ± 11.97%, 76.5 ± 7.88%, 76.53 ± 8.15%, respectively. The BIC values of NVFG and VFF group were significantly greater than MG group (P<0.001). On the other hand, there was not statistically significant difference between NVFG group and VFF group (P=0.999). NVFG as well as VFF can be considered as a promising method for augmentation of alveolar defects and the placement of the implants. The selection of non-vascularized graft or vascularized flap depends on the condition of the recipient site.

OP18.07: Isolated cleft lips: interest of ‘Cupid's bow’

Objectives: To evaluate usefulness of sagittal CDUS images for the differential diagnosis of fetal cleft lip (CL) and cleft palate (CP). Methods: We got coronal and axial images of upper lip and maxillary alveolar in 25 fetuses with CL and CP. Existence of defect and malalignment of alveolar was assessed. We assessed existence of hard palate defect on the mid-sagittal image and flow through the defect on CUDS during fetal swallowing. We compared the US findings with postnatal features. We assessed the accuracy of axial and sagittal images in the differential diagnosis of CL and CP. Results: 19 cases had CL and CP. 6 cases had CL without CP. 3 of 6 CL cases had cleft alveolar. Alveolar defect on axial image was detected in 18 of 19 cases with CP and 3 of 6 with CL. Alveolar malalignment was detected in 11 of 19 cases with CP, but in no case with CL. Hard palate defect on the sagittal image was detected in 15 of 19 cases with CP, but in no case with CL. CDUS evaluation of fetal swallowing was possible in 20 of 25 cases. Communicating flow through the palate defect was detected in 14 of 15 cases with CP, but in no case with CL. The accuracy of alveolar defect and malalignment on axial image were 84% and 68%, respectively. Accuracy of hard palate defect and flow on mid-sagittal image were 84% and 95%, respectively. Combined axial and sagittal images correctly diagnosed in all 6 cases with CL and 18 of 19 cases with CP. The accuracy was 96%. Conclusions: Sagittal US evaluation of the fetal hard palate may have additional value in the differential diagnosis of fetal CL and CP.

Evaluation of Maxillary Alveolar Reconstruction Using a Resorbable Collagen Sponge with Recombinant Human Bone Morphogenetic Protein-2 in Cleft Lip and Palate Patients

A resorbable collagen matrix with recombinant human bone morphogenetic protein (rhBMP-2) was compared with traditional iliac crest bone graft for the closure of alveolar defects during secondary dental eruption. Sixteen patients with unilateral cleft lip and palate, aged 8 to 12 years, were selected and randomly assigned to group 1 (rhBMP-2) or group 2 (iliac crest bone graft). Computed tomography was performed to assess both groups preoperatively and at months 6 and 12 postoperatively. Bone height and defect volume were calculated through Osirix Dicom Viewer (Pixmeo, Apple Inc.). Overall morbidity was recorded. Preoperative and follow-up examinations revealed progressive alveolar bone union in all patients. For group 1, final completion of the defect with a 65.0% mean bone height was detected 12 months postoperatively. For group 2, final completion of the defect with an 83.8% mean bone height was detected 6 months postoperatively. Dental eruption routinely occurred in both groups. Clinical complications included significant swelling in three group 1 patients (37.5%) and significant donor-site pain in seven group 2 patients (87.5%). For this select group of patients with immature skeleton, rhBMP-2 therapy resulted in satisfactory bone healing and reduced morbidity compared with traditional iliac crest bone grafting.