Tissue-engineered bone grafts for osteoplasty in patients with cleft alveolus.

Alveolar bone grafting is an integral part of the treatment concept in cleft palate patients. As an alternative to autogenous bone, tissue-engineered grafts have found some clinical application. The aim of the present study has been to compare ossification in the cleft area using tissue-engineered grafts in a case series of patients with ossification after transplantation of autogenous spongious bone as the gold standard in alveoloplasty. Eight children with complete cleft lips and cleft palates were included in the study. In four children (group A), the cleft defect was filled with tissue-engineered bone (autogenous osteoblasts cultured on demineralized bone matrix Osteovit(®)); as control in another 4 children (group B), the alveoloplasty was performed using spongious iliac bone. Preoperative and 6 months postoperative cone-beam computed tomography was performed, and volumes of the remaining cleft defects were calculated using 3D navigation software. Wound healing was uneventful in both groups. Six months postoperatively the mean volume of the cleft was 0.55±0.24cm(3) after grafting of tissue-engineered bone (group A) and 0.59±0.23cm(3) after transplantation of autogenous spongiosa. In group A, 40.9% of the cleft defect was ossified; in the control group (group B), 36.6%. Tissue-engineered bone is a promising alternative in alveolar bone grafting and no disadvantages were observed in comparison to the gold standard.

[Synthetic calcium phosphate ceramics in secondary alveoloplasty]. / Les céramiques phosphocalciques synthétiques dans l'alvéoloplastie secondaire.

INTRODUCTION: Bone substitutes are rarely used in the reconstruction of cleft lip and palate. The graft material of choice is cancellous bone, harvested in the hip or tibia. Tibial harvesting may lead to postoperative morbidity, or even complications. This has lead surgeons to develop alternative solution. We present a secondary alveolar bone grafting technique using synthetic calcium phosphate ceramics. OBSERVATION: A patient presenting with a complete unilateral cleft lip and palate was treated by alveolar bone grafting at the age of nine years, using a mixture of autologous bone, harvested on the operative field, and particles of biphasic calcium phosphate (BCP); the graft was included in a platelet rich plasma (PRP) gel. The patient was followed up for eight years after the procedure. No sign of early or late infection was observed. At the end of facial growth, the cuspid had erupted correctly in a safe periodontal environment. Sequential X-rays showed complete filling of the initial bone defect, progressive resorption of ceramics, and spontaneous eruption of the cuspid. DISCUSSION: In this long-term follow-up report, the use of BCP mixed with autologous bone did not interfere with dental eruption or maxilla growth. A second bone-harvesting site was thus avoided. BCP could be a suitable alternative to autologous bone graft for secondary alveoloplasty.

Bone regeneration using a hollow hydroxyapatite space-maintaining device for maxillary sinus floor augmentation--a clinical pilot study.

BACKGROUND: The mere lifting of the maxillary sinus membrane by implants protruding into the sinus cavity allows the establishment of a void space for blood clot and new bone formation. PURPOSE: To evaluate bone formation by using a spherical, hollow, and perforated hydroxyapatite space-maintaining device (HSMD) in a two-stage sinus lift procedure where residual alveolar bone height was ≤2 mm. MATERIAL AND METHODS: Spherical, hollow, and perforated HSMDs with a diameter of 12 mm were manufactured for this pilot study. Three patients with a residual bone height of 1-2 mm, as verified clinically and radiographically, and in need of a sinus augmentation procedure prior to implant installation were selected for the study. The HSMD and bone formation was evaluated by cone beam computerized tomography (CBCT) 6 months after augmentation procedure. Implants were installed 6 to 9 months after augmentation. The implant sites were prepared by a trephine drill to obtain a specimen of HSMD and bone for histological evaluation. After implant installation, the condition of the sinus membrane adjacent to the HSMD was evaluated endoscopically. After an additional 8 weeks, fixed partial prostheses were fabricated. RESULTS: Bone formation verified by CBCT was found around and inside the device in all three patients after 6 months. Despite the fact that residual bone before augmentation was ≤2 mm, 12-mm-long implants with diameter of 4.8 mm could be inserted with preservation of an intact and healthy sinus membrane verified endoscopically. Bone formation inside HSMDs was noted histologically in two out of three HSMDs. Implants were stable and without any marginal bone loss after 1 year of prosthetic loading. CONCLUSION: A spherical, hollow, and perforated HSMD used in sinus lift procedures can produce a void space for blood clot and new bone formation and subsequent implant installation.

Prospective evaluation of the use of motorized ridge expanders in guided bone regeneration for future implant sites.

The purposes of this prospective, randomized, controlled clinical investigation were to evaluate the performance of motorized ridge expanders (MREs) and to compare their results with those achieved using lateral ridge augmentation (LRA). Eight subjects with bilateral ridge deformities were selected. One technique was used on the right side and the other on the left. Implants were placed 6 months after bone augmentation procedures. All measurements were recorded at 2 and 5 mm from the most coronal aspect of the crest. The augmentation achieved with both techniques was statistically significant: 1.2 mm for LRA and 1.5 mm for MRE 2 mm from the crest and 1.5 mm for LRA and 1.6 mm for MRE at 5 mm from the crest. The differences between the two techniques were statistically insignificant. The amount of expansion achieved in the MRE sites appeared to be negatively correlated with the thickness of the cancellous bone (P < .05), and it was not affected by the thickness of the cortical plate. The MRE technique appears to be as effective as the LRA technique in augmenting the thickness of atrophic ridges. Defects treated with MREs showed less bone width contraction during the first 6 months of healing.

Horizontal alveolar ridge distraction in an edentulous patient.

PURPOSE: Full fixed dental rehabilitation, including attachment based over denture (to dental implants) is the optimal solution for edentulous patients, although the insertion of implants will be impossible when the alveolar ridge has been horizontally and severely absorbed. A full arch narrow ("knife-edge") alveolar crest creates a "borderline" condition. Dental implants cannot be inserted into a narrow ridge, which is also at risk of rapid absorption, especially under the pressure of a full denture. Current clinical solutions have been limited. In bone augmentation, the bone absorption rate has been approximately 50%, requiring 6-month therapy prolongation for the grafted bone to consolidate. MATERIALS AND METHODS: We have described an edentulous patient whose "knife-edge" maxillary alveolar crest was widened with crest expanders (horizontal distractors). RESULTS: Only 6 weeks after initiation of the distraction, a wide enough ridge had been created, allowing bilateral insertion of implants, followed by attachment-based full dental rehabilitation. Bone augmentation was avoided, and the implants were placed in the correct lateral position, with sufficient attached gingiva obtained. CONCLUSIONS: Horizontal crest expanding in narrow-alveolar edentulous patients can significantly reduce both morbidity and the therapeutic period and substantially increase the therapeutic success rate, based on both soft tissue and bone distraction. With this technique, our patient was without the denture for only 6 weeks.

The use of a diagnostic wax set-up in aesthetic cases involving crown lengthening--a case report.

UNLABELLED: Crown-lengthening surgery (CLS) consists of recontouring and repositioning the gingival margin as well as the alveolar crest. This technique results in the increase of the clinical crown height of teeth, which can consequently be advantageous in terms of improving retention and resistance, as well as aesthetics.The aim of this article is to demonstrate the uses of the diagnostic wax set-up and the subsequent production of surgical stents and templates to provide the patient with an initial intra-oral diagnostic mock-up for the process of obtaining consent, as well as acting as a useful guide for gingival and osseous recontouring in order to achieve a predictable, healthy and stable dento-gingival complex with pleasing aesthetics. CLINICAL RELEVANCE: The use of a well made diagnostic wax-up can provide valuable information to the dentist, laboratory, and patient which can be otherwise difficult to communicate.

Nontraumatic bone expansion for immediate dental implant placement: an analysis of 21 cases.

Ridge bone resorption is a common event that occurs in tooth loss areas and that can happen in different degrees. The harvesting of autogenous bone can significantly increase treatment time and costs, and poses some risks, including postoperative pain, or possibly nerve or arterial injury. The aim of this article is to demonstrate and analyze the use of bone expansion in order to circumvent problems related to bone harvesting. This is done with screws, followed by immediate implant placement. Twenty-one cases are used to define management solutions for this type of technique to enable the later implant rehabilitation of sites affected by poor bone width.

Gel-pressure technique for flapless transcrestal maxillary sinus floor elevation: a preliminary cadaveric study of a new surgical technique.

PURPOSE: To evaluate a novel surgical technique for flapless transcrestal elevation of the maxillary sinus floor via surgical templates using gel pressure. MATERIALS AND METHODS: Computed tomographic scans of fresh human cadaver maxillae and three-dimensional treatment planning software were used to design surgical templates. Access to the maxillary sinus was gained by guided transcrestal osteotomies to puncture the bony sinus floor. By injection of radiopaque gel, the maxillary sinus membrane was elevated to attain a postoperative bone height of 15 mm. RESULTS: The gel-pressure technique was performed in 10 atrophic maxillary sites with a mean residual bone height of the alveolar crest of 4.7 +/- 1.6 mm. The sinus membrane was successfully elevated in all sites without causing iatrogenic perforation (mean elevation height, 10.6 +/- 1.6 mm). CONCLUSIONS: The gel-pressure technique may provide a new option for minimally invasive transcrestal sinus surgery and may represent a safe method to increase bone volume in the atrophic posterior maxilla.

Alveolar distraction osteogenesis before placement of dental implants.

Distraction osteogenesis of the edentulous alveolar ridges may be considered an alternative to many other augmentation oriented surgical techniques. It is now being widely used for treating severe forms of alveolar ridge atrophy, especially before the placement of dental implants. Leibinger Endosseous Alveolar Distraction System (LEAD; Stryker Leibinger, Kalamazoo, MI) is an intraosseous distraction device used for edentulous ridges. In this study, the healing was uneventful in all 5 cases that were treated except 1, in which the vitality of the distraction segment could not be maintained. No complications related to the prosthodontic restoration were observed.

Five-year experience comparing resorbable to titanium miniplate osteosynthesis in cleft lip and palate orthognathic surgery.

OBJECTIVE: To evaluate 5-year outcome stability and complications in orthognathic surgery using resorbable versus titanium osteofixation. PATIENTS, METHODS: Twenty-two cleft lip and palate maxillary retrognathia cases were operated on using either poly (70L-lactide-co-30DL-lactide) or titanium miniplate osteofixation. All had two-piece Le Fort I maxillary advancement osteotomy, 11 had simultaneous mandibular setback, and 13 had alveolar bone grafts. RESULTS: Average operative movement and postoperative instability recorded for maxillary horizontal movement (A-point-Nasion) were 2.5 mm and 2.1 mm for the study group, compared with 6.3 mm and 1.9 mm for the control group. For maxillary vertical movement (ANS-Nasion), measured values were 4.9 and 1.3 mm for the study group and 2.3 and 0.9 mm for the controls. For mandibular horizontal movement, measured values were 10.7 mm and 2.8 mm for the study group and 1.9 mm and 0.8 mm for the controls. Gonial angle measures were 7.1 degrees and 3.5 degrees for the study group and 6.7 degrees and 3.1 degrees for the controls. Foreign body granuloma and fistulation occurred in 1 (9%) member of the study group, but was treated successfully with debridement; implant palpability subsided after 24 months. Three (27%) controls required plate removal, but the remaining plates were palpable. CONCLUSION: In the study group, horizontal maxillary stability appeared inferior to vertical stability, but mandibular stability was more reliable. Because groups were not matched for magnitude or direction of movement, the results of this study are preliminary and should be interpreted cautiously.

Alveolar vertical distraction osteogenesis: historical and biologic review and case presentation.

Dental rehabilitation of partially or totally edentulous patients with dental implants has become common practice in the last few decades, with reliable long-term results. However, local conditions of edentulous alveolar ridges may be unfavorable for implant placement. Vertically deficient alveolar ridges, in particular, may have insufficient bone volume to hold implants of adequate dimensions, making implant placement difficult or impossible. To correct this situation, a variety of surgical procedures have been proposed, including onlay bone grafts, vertical guided bone regeneration, and alveolar distraction osteogenesis. Distraction osteogenesis is a biologic process of new bone formation between the surfaces of bone segments that are gradually separated by incremental traction. This process is initiated when a traction force is applied to the bone segments and continues as long as the callus tissues are stretched. This traction force, in turn, generates tension within the tissues that connect the bone segments, which stimulates new bone formation parallel to the vector of distraction. The aim of this article is to provide clinicians with the historical background of and biologic basis for the concept of distraction osteogenesis, which can be traced back to the 1800s. Finally, a clinical case is presented to demonstrate a step-by-step application of alveolar distraction osteogenesis as a treatment protocol in a partially edentulous ridge for improvement of esthetics.

Osseous response following resective therapy with piezosurgery.

A piezoelectric instrument vibrating in the ultrasonic frequency range was investigated for its potential use in periodontal resective therapy. The rate of postoperative wound healing (baseline and 14, 28, and 56 days after surgery) in a dog model following surgical ostectomy and osteoplasty was the marker used to compare the efficacy of this instrument (PS) with a commonly used carbide bur (CB) or a diamond bur (DB). The surgical sites treated by CB or DB lost bone, in comparison to baseline measurements, by the 14th day, while the surgical sites treated by PS revealed a gain in the bone level. By day 28, the surgical sites treated by all three instruments demonstrated an increased bone level and regeneration of cementum and periodontal ligament. However, by day 56, the surgical sites treated by CB or DB evidenced a loss of bone, versus a bone gain in the PS-treated sites. Thus, it appears that PS provided more favorable osseous repair and remodeling than CB or DB when surgical ostectomy and osteoplasty procedures were performed. Therefore, PS could be regarded as being efficacious for use in osseous surgery.

Maintaining vector control during alveolar distraction osteogenesis: a technical note.

Distraction osteogenesis is a predictable method for restoring missing tissue prior to implant placement. However, pull from the soft tissue can alter the desired direction of the distraction. This article describes and illustrates techniques that are useful for maintaining the desired vector during alveolar distraction osteogenesis. These methods can prevent the need for further intervention and allow for ideal placement of endosseous dental implants without compromising results.

Closed-flap laser-assisted esthetic dentistry using Er:YSGG technology.

Use of a hard-/soft-tissue laser is a wonderful adjunctive tool for esthetic and restorative dentistry. The cases described here demonstrate some of the many ways in which this laser technology allows clinicians to make significant soft- and hard-tissue changes. These changes not only improve the final esthetic outcome of the case but also provide the biologic functional parameters required for successful dentistry.

[Experience with utilization of the Michigan splint for temporary splinting during osteogingivoplasty]. / Opyt ispol'zovaniia michiganskoi shiny dlia vremennogo shinirovaniia pri provedenii osteogingivoplastiki.

The experience of use Michigan splint for temporary splinting of the maxillary tooth at realization of flap surgery at 23 patients. Stages of clinical and laboratory procedures making the splint are described and analysed. Is appeared, that the reduction of mobility of teeth in the period following surgical intervention occurs on the average within 0.5-1 month faster, than with the patients after similar interventions, but without splinting. At the same time it is proved obvious, that the usage Michigan splint promotes normalization of functioning of muscles activity masticatory system and TMJ and helps in revealing of occlusal interferences.

The "FAD" (Floating Alveolar Device): a bidirectional distraction system for distraction osteogenesis of the alveolar process.

PURPOSE: The following study illustrates preoperative and perioperative vector management in alveolar distraction using a new distraction system--the "Floating Alveolar Device" (FAD). The FAD is a bidirectional alveolar distractor that allows augmentation of an atrophic alveolar process in several planes, assures easy intraoperative positioning of the planned vector of distraction, and provides correction of the horizontal position of the transported segment during and after vertical distraction. PATIENTS AND METHODS: The FAD is composed entirely of stainless steel and has the following basic components: an upper member, a distraction rod, a lower base plate supporting the vertical force of the distraction rod, a jointed hinge that connects the upper and the lower members, and a tightening rod that provides blocking of the hinge. The clinician can manipulate and adjust the tightening rods, allowing a change in the angle of the hinge, thereby altering the transverse dimension of the vector of distraction. A total of 4 patients aged to 19 to 40 years underwent bidirectional alveolar distraction. All procedures were performed in the mandible. RESULTS: In all treated patients, planned distraction height and direction were achieved. In all cases it was possible to place implants at the planned time. CONCLUSIONS: The most common complication, axial displacement, is easily eliminated by moving the bone with the "floating" rod of the FAD during or immediately after the distraction period, according to the principles of the floating bone concept.

The segmental ridge-split procedure.

This report details surgical procedures for ridge expansion by means of splitting the crest of an edentulous ridge. Atrophic bony ridges present a unique challenge to the dental implant surgeon. In the past, onlay grafts of bone harvested from the hip, maxillary tuberosity, symphysis of the chin, or external oblique ridge have all been used with success in reconstruction of atrophic ridges. However, bone onlay grafting procedures require a secondary surgical site, which exhibits typical postoperative morbidity associated with bone harvesting performed with chisels and burs. Additionally, onlay grafts often require a healing period of 6 months to a year before dental implants can be placed, and the onlay graft sometimes fails to fuse to the augmented site. The segmental ridge-split procedure provides a quicker method wherein an atrophic ridge can be predictably expanded and grafted with bone allograft, eliminating the need for a second surgical site.

Augmentation of the narrow traumatized anterior alveolar ridge to facilitate dental implant placement.

Traumatic tooth loss leads to alveolar resorption especially in sagittal direction. This can be due to avulsion of bone substance during the accident itself or due to resorption of the alveolar crest that takes place afterwards. Shortage of bone can prevent proper positioning of dental implants unless the volume of bone is increased before implantation. In the maxillary anterior area, this is also an esthetic problem. Several treatment modalities have been presented to augment the bone. This report reviews the latest literature on bone grafting, bone substitutes, guided bone regeneration, osteocompression and distraction which are potentially useful in the anterior maxilla. A special emphasis is paid to the versatility of using a crestal split osteotomy, by means of chisels and osteotomes to widen the narrow ridge. Three examples are illustrated showing onlay grafting, preservation of alveolar width with alloplastic coral material and lateral widening of a narrow maxillary alveolar ridge, using the crestal splitting technique.