Effect of decalcified freeze-dried bone allograft on the healing of jaw defects after cyst enucleation

Treatment of benign maxillomandibular osteolytic lesions larger than 4 cm: A systematic review

OBJECTIVE

This systematic review aimed to assess the different treatments of benign maxillo-mandibular radiolucent bone lesions over 4 cm to propose a management algorithm.

STUDY DESIGN

A literature search was conducted using MEDLINE/PubMed, Scopus, Google Scholar, Virtual Health Library databases, and gray literature. Randomized or non-randomized clinical trials and case series with 10 or more patients with a minimum follow up of 1 year, published in French or English until August 2023, were included. The risk of bias was assessed for all papers included.

RESULTS

Of 1433 records identified, 22 were included in this review, reporting data from 1364 lesions. Ameloblastoma was the most common lesion (51.22%) and mandible was the most common site (81.21%). Initial conservative treatment was prevalent (71.04%). Recurrence was higher after conservative (13.8%) than after radical treatments (6.5%). Multilocularity, cortical perforation, dental element preservation were linked to a higher recurrence risk.

CONCLUSION

This study has shown importance of understanding specific characteristics and recurrence risk in benign maxillomandibular osteolytic lesions. Multidisciplinary team approval, personalized approach based on lesion type and patient are crucial. The presence of at least one risk factor could lead to therapeutic decision. Despite limitations, the study informed lesion management and provided precise recommendations.

Clinical and radiographic study of the use of cross-linked gelfoam matrix in the treatment of dehiscence-like defects in Stage III periodontitis

Background

This clinical study aimed to overcome the difficulty of graft fixation and limited blood supply for dehiscence defects regeneration by using a cross-linked gelfoam matrix jointly with collagen membrane and xenograft.

Materials and Methods

The study included twenty dehiscence-like defects in maxillary anterior teeth with ≥4 mm facial bone loss and ≥5 mm clinical attachment loss (CAL) in patients suffering from Stage III periodontitis. Sites were treated with regenerative surgery using a cross-linked gelfoam matrix with glutaraldehyde, xenograft, and collagen membrane. The recorded parameters were: CAL, probing pocket depth (PPD), and radiographic three-dimensional (3D) volume for dehiscence-like defects (3D volume of facial bone defects) and 3D volume of interproximal defects using cone-beam radiographs. Data of these parameters were collected at both baseline and 6 months postsurgery. "Paired t-test" was used to assess the two variables."

Results

Both CAL and PPD showed statistically significant reductions and there was a significant bone gain at 6 months postsurgery in comparison to baseline (P ≤ 0.05).

Conclusion

Using a cross-linked gelfoam matrix with glutaraldehyde in combination with xenograft and collagen membrane could enhance the outcome of periodontal regeneration, especially in the treatment of challenging dehiscence defects.

Large dentigerous cyst associated with the maxillary impacted supernumerary teeth: A rare occurrence and literature review

Dentigerous cysts are common odontogenic cysts of the jaw but are rarely associated with supernumerary teeth. Few cases of large dentigerous cysts associated with anterior maxillary supernumerary teeth have been reported. The English literature has documented only four cases of dentigerous cysts>40 mm in diameter associated with supernumerary teeth. A 47-year-old man was referred to our hospital, complaining of minor pain in the maxillary gingiva. Computed tomography revealed a well-defined oval unilocular radiolucent lesion (50×45×35 mm) in the right maxilla, including two impacted supernumerary teeth. A dentigerous cyst associated with impacted anterior maxillary supernumerary teeth was diagnosed. The two impacted teeth were surgically removed, and the cyst was enucleated using the Caldwell-Luc approach. Histopathology confirmed the diagnosis of a large dentigerous cyst associated with impacted anterior maxillary supernumerary teeth. The postoperative course has been uneventful for two years. We also reviewed the relevant English literature.

Successful management of spontaneous bone regeneration after jaws cystectomy using PRGF approach; case series

In the jaws, the healing process of bone defects occurs differently compared with other anatomical sites where healing is done by the formation of scar tissue. This is due to physiological bone remodeling and continuous bone resorption and apposition. In the case of large cysts, there is an increased risk of postoperative infection due to the retraction of the blood clot on the bony walls. The use of plasma rich in growth factors (PRGF), with or without autologous bone addition, for filling the cystic cavities is beneficial not only for its antimicrobial effect, but also due to simultaneously release of growth factors from platelet alpha granules and adhesive proteins. The aim of our work was to emphasize the spontaneous bone healing of the maxilla and mandible after the enucleation of large and medium-sized cysts in asymptomatic patients of different age. The outcome of three patients who underwent surgery for removal of radicular cysts is presented. Imagistic [cone-beam computed tomography (CBCT)] and histological examination was performed aiming to evaluate the quality of new bone at the site of the bone defect, after different time intervals. By using PRGF approach, the healing of mandibular bone occurred 18 months after cystectomy in a smoker patient, 54-year-old, while the healing of maxillary bone using autologous bone mixed with PRGF occurred after six months in a 63-year-old patient. In a young patient (14 years old), the regeneration period was six months, using PRGF and a fibrin cloth for filling the defect.

Efficacy of decalcified freeze-dried bone allograft in the regeneration of small osseous defect: A comparative study

Aim:

To access the efficacy of decalcified freeze-dried bone allograft (DFDBA) in the regeneration of bone following small osseous defect in minor oral surgery.

Objectives:

To evaluate the ability of DFDBA to enhance the rate of wound healing and assess radiographic bone density, pain, and infection preoperatively and postoperatively.

Materials and Methods:

Twenty patients with cysts were assessed. Ten patients were filled with DFDBA (Group 1) and ten without bone graft (Group 2), respectively. Radiographic bone density was assessed on preoperative, intraoperative, and postoperative radiographs on 1^st day, 3^rd month, and at 6^th month using Adobe Photoshop CS6 - Grayscale histogram.

Results:

Bone density in Group 1 was found to be significantly higher than in Group 2 on 3^rd and 6^th month postoperatively with a P = 0.024 and P = 0.016 which was statistically significant. The percentage increase in bone density between both the group was determined and yielded no difference over a period of time, but the difference in percentage increase was markedly higher in Group 1 compared to Group 2 at all the time intervals.

Conclusion:

Bone formed as depicted by bone density is significantly higher when DFDBA is used in small bony defects.

Autogenous Partial Bone Chip Grafting on the Exposed Inferior Alveolar Nerve After Cystic Enucleation

This prospective study evaluated the clinical effectiveness of the new approach of partial autogenous bone chip grafts for the treatment of mandibular cystic lesions related to the inferior alveolar nerve (IAN). A total of 38 patients treated for mandibular cysts or benign tumors were included in this prospective study and subsequently divided into 3 groups depending on the bone grafting method used: cystic enucleation without a bone graft (group 1), partial bone chip graft covering the exposed IAN (group 2), and autogenous bone graft covering the entire defect (group 3). We evaluated the symptoms, clinical signs, and radiographic changes using dental panorama preoperatively, immediate postoperatively, and at 1, 3, 6, and 12 months postoperatively. Radiographic densities were compared using Adobe Photoshop CS5 (Adobe Systems Inc., San Jose, CA). Repeated measures analysis of variance was used for statistical evaluation with SPSS 22.0 (SPSS Inc, Chicago, IL), and P < 0.05 was considered statistically significant.Radiopacities were the most increased at 1 year postoperative in group 3; groups 2 and 3 did not show statistically significant differences, whereas groups 1 and 3 were statistically significant. In terms of radiographic bone healing with clinical regeneration of the exposed IAN, healing occurred in all patients, although the best healing was achieved in group 2.This autogenous partial bone chip grafting procedure to cover the exposed IAN is suggested as a new surgical protocol for the treatment of cystic lesions associated with the IAN.

Effects of Rat Bone Marrow-Derived Mesenchymal Stem Cells and Demineralized Bone Matrix on Cranial Bone Healing

BACKGROUND

Studies in tissue engineering about mesenchymal stem cells (MSCs) provide promising results for bone regeneration. The aim of this study was to evaluate the effects of rat bone marrow-derived MSCs (rMSCs) alone and when combined with demineralized bone matrix (DBM) on critical-sized cranial defects of rats.

METHODS

Ten rats were used to obtain allogeneic rMSCs. Forty rats were separated equally into 4 groups. A full-thickness circular bone defect was created in the frontal bone of the rats. Group 1 was an operative control group. In group 2 DBM, in group 3 rMSCs, and in group 4 DBM combined with rMSCs were applied into the defects. Bone regeneration was evaluated by computed tomographic analysis and immunohistochemistry.

RESULTS

In radiological evaluation, the percentage of area healed in group 3 at the 12th week was statistically significantly greater than in group 1. In group 3 and group 4, distributed healing patterns were observed more than in group 2 and in group 1. Immunohistochemical evaluation revealed that group 4 had the best osteoinductive potential. Osteoinductive potential of group 3 was similar to group 2 and was better than group 1.

CONCLUSIONS

Allogeneic rMSC applications have created a statistically significant radiologic reduction of the bone defect areas at the end of the 12 weeks. The MSC applications have also increased the bone density and changed the healing patterns. Combined use of the DBM and rMSCs has created more osteoinductive responses. This combination can provide better results in craniofacial bone reconstruction.

Clinical and Microcomputed Topography Evaluation of the Concentrated Growth Factors as a Sole Material in a Cystic Bony Defect in Alveolar Bone Followed by Dental Implantation: A Case Report

Concentrated growth factors (CGFs) can be used to enhance wound healing. This case report describes a short-term effect of CGF grafting followed by implant placement in a cystic bony defect within the mandible. Healing conditions were monitored by 2 implant-related surgeries, radiographs, and a microcomputed topography examination. Continuous increase of radiopacity in radiographs was noticed till 6 months after grafting. Bone core specimen was taken at 3.5 months after grafting, and percent bone volume reached 32.7% analyzed by microcomputed topography. In conclusion, the present case showed bone regeneration in the cystic bony defect grafted by CGFs alone.

Mesenchymal stem cells in post-surgical cavities of large maxillary bone lesions

BACKGROUND

Recent studies have highlighted that MSCs are capable of regenerating large bone defects when used in combination with bone substitutes and increasing allo-graft osteointegration. We investigated the hypothesis that autologous MSCs may lead to increased bone regeneration and reduced healing time in post-surgical cavities of large maxillary bone lesions.

METHODS

This study involved 10 patients (TEST GROUP) (6 males and 4 females). All patients had expansive mandibular lesions larger than 3 cm. From the surgical point of view, the 10 patients were treated with MSCs (withdrawal of the iliac crest bone marrow BMMSs) directly into the post-surgical cavity, without the addition of filler.

RESULTS

and radiological data, in the postoperative, were compared to those of patients who did not receive any grafting of MSCs. The 7 patients with mandibular lesions showed a rapid and very good healing with an 85-90% ossification of the major defect at 12 months.

CONCLUSIONS

Through the use of stem cells a greater ossification of the residual cavity (85-90%) was observed at 12 months after surgical enucleation in contenitive defects.

Evaluation of Spontaneous Bone Regeneration after Enucleation of Large Cysts of the Jaws using Radiographic Computed Software

Introduction

Spontaneous regeneration of bone is commonly seen in the small surgical defects caused by enucleation of cysts. However, in case of large surgical defects caused by the enucleation, spontaneous regeneration of bone is a rare phenomenon and it depends on factors, such as age of the patient, intact periosteum, and proper stabilization.

Materials and methods

The study included 16 patients, who reported to the department of oral and maxillofacial surgery with the complaint of pain and swelling in the jaws diagnosed as cyst. The sample included equal numbers of male and female subjects aged between 15 and 40 years. Panoramic radiographs were taken pre- and postoperatively on day 2 of the enucleation.

The dimensions of the cyst were evaluated on the radiograph according to the proforma.

Subsequent radiographs were taken at regular intervals of 1.5, 3, and 6 months using standard parameters and were analyzed using MCID™ analysis software of imaging research.

Results

Mean reduction was seen in up to 39 and 60% in the cystic cavity size and increase in the mean density up to 59 and 90.2% at 3 and 6 months intervals respectively.

Conclusion

Spontaneous bone regeneration was seen even after primary closure of the large cystic defect without the need for placement of foreign substances or grafts and it also eliminated the complications resulting from placement of foreign substance. Further studies are required in a larger sample with longer follow-up durations to confirm the outcome of the present work for the benefit of patients.

Clinical significance

The present study depicted that spontaneous bone regeneration can occur with accepted results after simple enucleation of jaw cyst without the aid of any graft material. Hence, simple enucleation may be considered as a first line of treatment modality for cystic lesion of the jaws. This simplifies the surgical procedure, decreases the economic and biologic costs, and reduces the risk of postoperative complications. Follow-up is necessary along with patient's compliance for the success of treatment.

How to cite this article

Wagdargi SS, Rai KK, Arunkumar KV, Katkol B, Arakeri G. Evaluation of Spontaneous Bone Regeneration after Enucleation of Large Cysts of the Jaws using Radiographic Computed Software. J Contemp Dent Pract 2016;17(6):489-495.

Interventions for the treatment of keratocystic odontogenic tumours

BACKGROUND

The keratocystic odontogenic tumours (KCOTs) account for between about 2% and 11% of all jaw cysts and can occur at any age. They are more common in males than females with a male:female ratio of approximately 2:1. Although they are benign, KCOTs are locally very aggressive and have a tendency to recur after treatment. Reported recurrence rates range from 3% to 60%. The traditional method for the treatment of most KCOTs is surgical enucleation. However, due to the lining of the cyst being delicate and the fact that they frequently recur, this method alone is not sufficient. Adjunctive surgical treatment has been proposed in addition to the surgical enucleation, such as removal of the peripheral bone (ostectomy) or resection of the cyst with surrounding bone (en-bloc) resection. Other adjunctive treatments proposed are: cryotherapy (freezing) with liquid nitrogen and the use of the fixative Carnoy's solution placed in the cyst cavity after enucleation; both of which attempt to address residual tissue to prevent recurrence.

OBJECTIVES

To assess the available evidence comparing the effectiveness of interventions for the treatment of KCOTs.

SEARCH METHODS

We searched the following electronic databases: the Cochrane Oral Health Group Trials Register (to 17 March 2015), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, 2015, Issue 2), MEDLINE via Ovid (1946 to 17 March 2015) and EMBASE via Ovid (1980 to 17 March 2015). We searched the US National Institutes of Health Trials Register (http://clinicaltrials.gov) and the WHO Clinical Trials Registry Platform for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases.

SELECTION CRITERIA

Randomised controlled trials comparing one modality of intervention with another with or without adjunctive treatment for the treatment of KCOTs. Adults, over the age of 18 with a validated diagnosis of solitary KCOTs arising in the jaw bones of the maxilla or mandible. Patients with known Gorlin syndrome were to be excluded.

DATA COLLECTION AND ANALYSIS

Review authors screened trials for inclusion. Full papers were obtained for relevant and potentially relevant trials. If data had been extracted, it would have been synthesised using the fixed-effect model, if substantial clinical diversity were identified between studies we planned to use the random-effects model with studies grouped by action provided there were four or more studies included in the meta-analysis, and we would have explored the heterogeneity between the included studies.

MAIN RESULTS

No randomised controlled trials that met the inclusion criteria were identified.

AUTHORS' CONCLUSIONS

There are no published randomised controlled trials relevant to this review question, therefore no conclusions could be reached about the effectiveness or otherwise of the interventions considered in this review. There is a need for well designed and conducted randomised controlled trials to evaluate treatments for KCOTs.

Spontaneous Bone Regeneration After Enucleation of Large Jaw Cysts: A Digital Radiographic Analysis of 44 Consecutive Cases

PURPOSE

This study evaluated the healing in cystic defect of the jaw to substantiate our understanding of spontaneous bone healing after enucleation of jaw cysts subjectively and with analysis of digital postoperative panoramic radiographs.

MATERIALS AND METHODS

Fourty four consecutive patients reporting to the Department of Dental and Oral Surgery, during the period between 2008-2012 having maxillary and mandibular cysts treated by either surgical enucleation or by marsupialization followed by enucleation were evaluated for subsequent bone formation at the site of cystectomy defect by subjective clinical examination along with digital radiographic examination. Postoperative clinical and radiographic examinations were performed at 6,9,12, and 24 months. Bone regeneration was evaluated by reduction of the size of residual cavities at the cystectomy defect using digital orthopantomogram.

RESULTS

Out of 44 patients 15 patients completed two years of follow-up with all the patients having 6 months follow-up. The maximum size of the cystic pathology was 150.40mm and minimum of 14.73mm at the time of presentation (average size of 58.16mm). Twenty patients were diagnosed with odontogenic keratocyst, with one patient having multiple OKC associated with Gorlin Goltz Syndrome, 17 patients had dentigerous cyst, 5 had Radicular cyst; solitary bone cyst and globulomaxillary cyst formed one each. Uneventful healing and spontaneous filling of the residual cavities were obtained in all cases. The digital analysis of the postoperative radiographs showed mean values of reduction in size of the residual cavity of 25.85% after 6 months, 57.13% after 9 months, 81.03% after one year and 100% after two year.

CONCLUSION

Spontaneous bone regeneration can occur after surgical removal of jaw cysts without the aid of any graft materials even in large cystic cavity sufficiently surrounded by enough bony walls. This simplifies the surgical procedure, decreases the overall cost of surgery, and reduces the risk of postoperative complications associated with grafting.

Spontaneous Bone Healing after Cysts Enucleation without Bone Grafting Materials: A Randomized Clinical Study

The aim of this study was to evaluate spontaneous bone regeneration after cysts enucleation of the jaws without the use of bone grafting materials. We included 18 patients at random (11 men and 7 women) with a mean age of 31.8 years, with jaw cysts treated by enucleation, without the use of grafting materials. A method of measurements to assess the percentage of reduction of the bone cavities was used to objectify the results. The patients were evaluated before and at least 6 months after surgery, with radiographic scans based on linear measures with a computerized method using Nemoceph program (Nemotec, NemoCeph Software, Madrid, España). The analysis of the sample shows an average of 85.59% decrease in horizontal measures, 89.53% in the vertical, and 88.98 and 89.81% in the diagonal left and right, respectively. The total average reduction was 88.47%. It showed a greater decrease in vertical and diagonal measurements with respect to horizontal. Regeneration in 12 patients was 100% and in 6 patients was higher at 50.4%. Bone density increased in the postoperative radiographs. The results suggest that in some cases, spontaneous bone regeneration can be achieved by cysts enucleation without bone grafting materials.

Histologic and histomorphometric assessment of eggshell-derived bone graft substitutes on bone healing in rats

OBJECTIVE

The objective of this study was to histologically and histomorphometrically evaluate the efficacy of the new formulations of eggshell-derived calcium carbonate in rats.

STUDY DESIGN

The study was conducted on 30 adult male rats. Four standardized and circular intrabony defects were created in the both maxilla and mandibula of each animal. Three different graft materials were prepared as follows: 1) Material A: Eggshell-derived calcium carbonate combined with carrageenan gel, 2) Material B: Eggshell-derived calcium carbonate combined with xanthan gum gel, and 3) Material C: Eggshell-derived calcium carbonate powder. The right mandibular defect sites were grafted with Material A in all animals, and defects on the left were grafted with Material B. Defects on the right side of maxilla were received Material C in all animals, and all left maxillary defects were remained untreated as controls. The animals were sacrificed either postoperatively on the 15th day, postoperatively on the 30th day or postoperatively on the 45th day. Histomorphometric measurements were made of the areas of newly formed bone, necrotic bone, fibrous tissue and residual graft material.

RESULTS

Material A exhibited the highest level of osteoid formation followed by Material B and Material C on the 45th day. In terms of osteoid formation, statistically significant differences were observed between graft materials and controls at 45th day compared to 15th and 30th day (p<0.05).

CONCLUSIONS

Eggshell-derived graft substitutes in both gel and powder forms are biocompatible materials which may have the potential to enhance the new bone formation. Key words:Bone graft material, bone defects, eggshell, histopathological evaluation, rat.

Cystic lesions of the jaws - a clinicopathological study of 322 cases and review of the literature

Three hundred and twenty-two patients (192 male and 130 female) with cystic lesions of the jaw were successfully diagnosed and treated. One hundred and fifty-five (48%) were radicular cysts, 80 (25%) were dentigerous cysts, 23 (7%) were odontogenic keratocyst (=keratocystic odontogenic tumor), 19 (6%) were eruption cysts, 16 (5%) were traumatic bone cysts, and 29 (9%) were non-odontogenic cysts. There were 95 in the pediatric age group (1 month to 16 years) and 227 in the adult age group (17 years and older). Male to female ratio was 1 in the pediatric age group and 1.7 in the adult age group. The treatment modalities were: marsupialization, enucleation, enucleation with bone grafting, or resection. The distribution and characteristics of jaw cysts in children are different from those in adults. In children there is a relatively high rate of developmental cysts, whereas in adults the inflammatory cysts are more common. Following enucleation of a cystic jaw lesion, the entire surgical specimen and not only a biopsy specimen, should be examined histopathologically to prevent any possibility of an intramural squamous cell carcinoma that may be overlooked. The differences in prevalence of each type of jaw cyst during a lifetime may point toward a multifactorial polygenic pattern rather than a monogenic pattern.

Reconstruction of cranial bone defects using Struthio camelus eggshell

BACKGROUND

There are many synthetic materials for the treatment of bone defects, which have their own advantages and disadvantages. We aimed to compare the efficacy of ostrich eggshell, which is cheap and easily available, and demineralized bone matrix in healing of cranial bone defects.

METHODS

A full-thickness circular bone defect was created in the frontal bone of 40 Wistar rats. Group 1 was the operative control group. In group 2, demineralized bone matrix applied into the defects; in group 3, Struthio camelus (ostrich) eggshell implants (OSIs) were applied into the defects; and in group 4, ostrich eggshell powders were applied into the defects. Computed tomographic analysis was performed to evaluate the healing of bone defects, the bone density, the OSI area measurements, and the OSI volume and density. At the end of the 24th week, all rats were killed. New bone formation, infection, resorption, and tissue reactions were evaluated.

RESULTS

Ostrich eggshell implants were slightly resorbed, integrated with bone, stable, and supplied good cranial completeness. Ostrich eggshell powders were totally resorbed at the sixth month. There were no significant differences between control and ostrich eggshell groups in new bone formation.

CONCLUSIONS

Ostrich eggshell did not seem to be an osteoproductive material, but it has some important advantages as an implant. Ostrich eggshell has a strong structure, is cheap, is shaped easily, and does not cause tissue reaction or infection. Ostrich eggshell could be a good alternative graft material for craniomaxillofacial procedures. Further studies are required to find out the potential use of the ostrich eggshell in craniomaxillofacial reconstructions.

Blood vessel formation in the tissue-engineered bone with the constitutively active form of HIF-1α mediated BMSCs

The successful clinical outcome of the implanted tissue-engineered bone is dependent on the establishment of a functional vascular network. A gene-enhanced tissue engineering represents a promising approach for vascularization. Our previous study indicated that hypoxia-inducible factor-1α (HIF-1α) can up-regulate the expression of vascular endothelial growth factor (VEGF) and stromal-derived factor 1 (SDF-1) in bone mesenchymal stem cells (BMSCs). The angiogenesis is a co-ordinated process that requires the participation of multiple angiogenic factors. To further explore the angiogenic effect of HIF-1α mediated stem cells, in this study, we systematically evaluated the function of HIF-1α in enhancing BMSCs angiogenesis in vitro and in vivo. A constitutively active form of HIF-1α (CA5) was inserted into a lentivirus vector and transduced into BMSCs, and its effect on vascularization and vascular remodeling was further evaluated in a rat critical-sized calvarial defects model with a gelatin sponge (GS) scaffold. The expression of the key angiogenic factors including VEGF, SDF-1, basic fibroblast growth factor (bFGF), placental growth factor (PLGF), angiopoietin 1 (ANGPT1), and stem cell factor (SCF) at both mRNAs and proteins levels in BMSCs were significantly enhanced by HIF-1α overexpression compared to the in vitro control group. In addition, HIF-1α-over expressing BMSCs showed dramatically improved blood vessel formation in the tissue-engineered bone as analyzed by photography of specimen, micro-CT, and histology. These data confirm the important role of HIF-1α in angiogenesis in tissue-engineered bone. Improved understanding of the mechanisms of angiogenesis may offer exciting therapeutic opportunities for vascularization, vascular remodeling, and bone defect repair using tissue engineering strategies in the future.

Jaw cysts - filling or no filling after enucleation? A review

INTRODUCTION

Jaw cysts are common lesions in the oral and maxillofacial region. Enucleation of the lesions and primary closure of the defects, the so-called "cystectomy", has evolved as the treatment of choice. In order to reduce infections and to accelerate bone regeneration, different types of bone grafts are increasingly investigated for defect filling.

MATERIAL AND METHODS

The present review reflects the most recent studies using autogenous, allogenic, xenogenic and alloplastic bone grafts and compares the results to current investigations about conservative cyst enucleation without using any filling materials. Relevant studies with significant patient sample sizes were electronically searched in PubMed and Medline.

RESULTS

Simple cyst enucleation and blood clot healing show low complication rates and sufficient bone regeneration even in large defects. Prospective randomized trials comparing the additional use of filling materials to the "cystectomy" are rare. Currently available data do not indicate the superiority of additional bone grafts.

CONCLUSION

Enucleation of jaw cysts and primary closure without bone substitutes remains "state of the art" in most cases.

A comparative evaluation of decalcified freeze dried bone allograft, hydroxyapatite and their combination in osseous defects of the jaws

OBJECTIVES

To evaluate decalcified freeze dried allograft or hydroxyapatite and a combination of both as bone autograft substitutes in the healing of osseous jaw defects.

MATERIALS AND METHODS

24 patients participated in the study which involved the filling of osseous defects in the maxilla/mandible with decalcified freeze dried bone allograft (DFDBA) or hydroxyapatite (HA) or a combined graft composed of these two in equal proportions.

RESULTS

Bone formation occurred as early as 4 weeks in the DFDBA and combination groups and 12 weeks in the HA group which was verified by radiographs, Dentascans (DentaScan® Software Program, General Electric, USA) and bone scintigraphy.

CONCLUSION

Both these materials can be used as bone graft substitutes in smaller defects although their suitability in large defects is yet to be studied.

Interventions for the treatment of keratocystic odontogenic tumours (KCOT, odontogenic keratocysts (OKC))

BACKGROUND

The keratocystic odontogenic tumours (KCOTs) account for between about 2% and 11% of all jaw cysts and can occur at any age. They are more common in males than females with a male:female ratio of approximately 2:1. Although they are benign, KCOTs are locally very aggressive and have a tendency to recur after treatment, reported recurrence rates range from 3% to 60%. The traditional method for the treatment of most KCOTs is surgical enucleation. However, due to the lining of the cyst being delicate and the fact that they frequently recur, this method alone is not sufficient. Adjunctive surgical treatment has been proposed in addition to the surgical enucleation, such as removal of the peripheral bone (ostectomy) or resection of the cyst with surrounding bone (en-bloc) resection. Other adjunctive treatments proposed are: cryotherapy (freezing) with liquid nitrogen and the use of the fixative Carnoy's solution placed in the cyst cavity after enucleation; both of which attempt to address residual tissue to prevent recurrence.

OBJECTIVES

To assess the available evidence comparing the effectiveness of surgical interventions and adjuncts for the treatment of KCOTs.

SEARCH STRATEGY

Databases searched were: the Cochrane Oral Health Group's Trials Register (to 28th July 2010), CENTRAL (The Cochrane Library 2010, Issue 3), MEDLINE (from 1950 to 28th July 2010), and EMBASE (from 1980 to 28th July 2010). The reference lists of all trials identified were cross checked for additional trials. There were no language restrictions and several articles were translated.

SELECTION CRITERIA

Randomised controlled trials comparing one modality of surgical intervention with another with or without adjunctive treatment for the treatment of KCOTs. Adults, over the age of 18 with a validated diagnosis of solitary KCOTs arising in the jaw bones of the maxilla or mandible. Patients with known Gorlin syndrome were to be excluded.

DATA COLLECTION AND ANALYSIS

Review authors screened trials for inclusion. Full papers were obtained for relevant and potentially relevant trials. If data had been extracted, it would have been synthesised using the fixed-effect model, if substantial clinical diversity were identified between studies we planned to use the random-effects model with studies grouped by action provided there were four or more studies included in the meta-analysis, and we would have explored the heterogeneity between the included studies.

MAIN RESULTS

No randomised controlled trials that met the inclusion criteria were identified.

AUTHORS' CONCLUSIONS

There are no published randomised controlled trials relevant to this review question, therefore no conclusions could be reached about the effectiveness or otherwise of the interventions considered in this review. There is a need for well designed and conducted randomised controlled trials to evaluate treatments for KCOTs.

Healing assessment of osseous defects of periapical lesions with use of freeze dried bone allograft

OBJECTIVES

The aim of this study was to save endodontically failed teeth with periapical pathosis by surgery. Elimination of the periapical pathology and to evaluate the clinical and radiological efficiency of freeze dried bone allograft in bony defects.

MATERIALS AND METHODS

Ten patients were included in this study with established periapical pathology with the need for periapical surgery after failed endodontic therapy. Surgery was decided after the cessation of acute symptoms. Patients on regular medications for known medical complications were excluded from the study. A full thickness flap or modified Leubke-ochsecnbein was raised depending upon the size and location of the lesion. Thorough periapical curettage was performed to remove the pathological tissue surrounding the apices and the root of the tooth. The graft material was mixed with patient's venous blood drawn earlier from a peripheral vein to make it more cohesive. The graft material mixed with blood was then carefully packed with light pressure into the defect. The flap was replaced. All the patients received broad spectrum antibiotics one day before and five days after surgery. The cases were followed up with clinical and radiological examination and were recalled at intervals of 1 month, 3 months and 5 months postoperatively to assess the condition of the periapical area.

RESULTS

In all the ten cases at the end of 1st month postoperatively a well defined border separating the host bone from the graft material indicating simultaneous resorption of the graft. This resorption continued at 3 months follow up indicating continued graft resorption and also increasing radioopacity, haziness indicating bone regeneration. Eight of the ten patients could be evaluated at the end of fifth month and radiographs showed increase in radioopacity and reduction in size of periapical radiolucency as well as normal trabecular pattern of the bone.

CONCLUSION

The results demonstrate successful use of FDBA in the treatment of osseous defects of periapical lesions associated with failed endodontically treated teeth.

Evaluation of the biocompatibility and osteoproductive activity of ostrich eggshell powder in experimentally induced calvarial defects in rabbits

The purpose of this study was to investigate the beneficial effects of particulate ostrich eggshell grafting on the healing of experimentally induced skull defects. The clinical, radiological, histological, and histomorphometrical findings of this material were compared with the results of commercially available demineralized bone matrix (DBM). The study was conducted on 18 adult New Zealand rabbits. One defect served as a control and the remaining ones either were filled with different sized eggshell particles or DBM, in each animal. Clinical and radiological inspections and histologic investigations of the animals were done at the 1st, 3rd, and 6th months of postoperative period. Radiologically, minimal bone regeneration was observed at the empty, control defect sites. The most advanced bone regeneration was in the DBM grafted defects. The eggshell particle grafted defect sites displayed weak bone regeneration at earlier stages, at 1st and 3rd months after operation when compared with demineralized bone matrix. Nevertheless, ossification was satisfactory at 6th month after operation when compared with the control defects. Within the limitations of this study, it was concluded that Ostrich eggshell powder (OSP) is a worth-while bone substitute because it is a safe, cheap, and easily available material. Long-term studies will clarify its possible role in maxillofacial surgery. Further sophisticated experiments should be undertaken before human implantation concerning its osteoproductive activity alone or in combination with other materials.

Gelatin sponges (Gelfoam) as a scaffold for osteoblasts

Gelatine sponge because of its flexibility, biocompatibility, and biodegradability, has the potential to be used as a scaffold to support osteoblasts and to promote bone regeneration in defective areas. This study aimed to determine osteoblast proliferation, differentiation, and integration in modified and un-modified gelatine sponges. Three scaffolds were studied: gelatine sponge (Gelfoam), gelatin sponge/mineral (hydroxyapatite) composite, and gelatin sponge/polymer (poly-lactide-co-glycolide) composite. 2-D plastic coverslip was used as control. The gelatin sponges were modified using PLGA coating and mineral deposition to increase biodegradation resistance and osteoblast proliferation respectively. The scaffolds were characterized using Scanning Electron Microscopy (SEM) and X-ray diffraction. Cell number (DNA content), cell-replication rate (thymidine assay), and cell differentiation (alkaline phosphatase activity) were measured 24 h, 3 days, and 1, 2, 3 weeks after the osteoblast-like cells were cultured onto the scaffolds. Cell penetration into the sponges was determined using haematoxylin-eosin staining. Both modified and unmodified gelatine sponges demonstrated ability to support cell growth and cells were able to penetrate into the sponge pores. In a comparison of different scaffolds, cell number and cell replication were highest in sponge/hydroxyapatite composite and lowest in sponge/PLGA composite.

Healing of bone defects by an osteopromotion technique using solvent-dehydrated cortical bone plate: a clinical and radiological study

Osseous defects of the jaws following trauma, cysts, infection or congenital deformity may show poor osteogenesis and the affected area may never be completely filled with bone. It is widely accepted in guided tissue regeneration that physically halting soft connective tissue proliferation into bone allows bone regeneration. This concept is called the "osteopromotion principle." The purpose of the present study was to evaluate the effect of solvent-dehydrated cortical bone plates as a barrier to allow bone regeneration by assessing the osteopromotion principle. 30 patients (18 male, 12 female) with cystic lesions of the jaws were assigned to two different groups. The patients in Group A were treated by enucleation. In Group B, were treated by removal of the lesion and placing a solvent-dehydrated cortical bone plate on top of the cyst cavity to avoid ingrowth of connective tissue. Both groups were evaluated radiographically using spiral-computed tomography (CT) before surgery and 12 months postoperatively. In group B, all cystic cavities showed complete bone healing in 12 months. At the same period, invasion of the soft connective tissue were observed in the patients treated only by enuclation. This study demonstrates that solvent-dehydrated cortical bone plates can be used as a barrier in treatment of cyst cavities and they hinder ingrowth of connective tissues and promote successful bone healing.

Bone regeneration after enucleation of mandibular cysts: Comparing autogenous grafts from tissue-engineered bone and iliac bone

OBJECTIVE

The aim of this study was to compare bone regeneration after grafting enucleated mandibular cyst cavities using either autogenous osteoblasts cultured on a biomaterial or autogenous spongiose iliac bone.

STUDY DESIGN

Twenty patients with 22 mandibular cysts were assessed. Eleven cysts were filled in with tissue-engineered bone (autogenous osteblasts cultured on demineralized bone matrix Osteovit) and 11 with spongiose iliac bone as controls. Panoramic radiographs were taken preoperatively, immediately postoperatively, and 3, 6, and 12 months after surgery. Radiolucency was computer analyzed using gray-level histograms.

RESULTS

In both groups bone regeneration took place in a similar fashion. After 3 and 6 months there were few differences in bone density between the groups. However, in radiographic controls after 12 months ossification was considerably stronger in cysts grafted with tissue-engineered bone.

CONCLUSION

These results advocate for the clinical application of tissue-engineered bone as an alternative viable filling material for cysts.

Upper lip swelling caused by a large dentigerous cyst

Swelling of the upper lip can result from various diseases such as salivary tumors, infectious and inflammatory diseases and cysts. Among the latter, dentigerous cysts, typically involving unerupted teeth, are sometimes associated with supernumerary teeth in the maxillary anterior incisors region called the mesiodens. We report an unusual case of a large dentigerous cyst associated with an impacted mesiodens in a 42-year-old male who presented with a slow-growing swelling in the upper lip.

Bone defects of the facial skeleton - replacement with biomaterials

The authors report on their experience with bone defect treatment following surgery of jaw-bone cysts. This is based on the use of cadaveric ground spongiosis saturated with tetracycline and metronidazol solution. The study shows the above mentioned material is very suitable for bone defect therapy, and cost effective. The results were verified by clinical and X-ray examination.

Spontaneous bone regeneration after enucleation of large mandibular cysts: a radiographic computed analysis of 27 consecutive cases

PURPOSE

This study evaluated the spontaneous bone healing after enucleation of large mandibular cysts subjectively and with a computed analysis of postoperative panoramic radiographs.

PATIENTS AND METHODS

Twenty-nine patients had large mandibular cysts treated by surgical enucleation. Postoperative clinical and radiographic examinations were performed at 6, 12, and 24 months in 27 patients. Bone regeneration and reduction of the residual cavities and bone density were evaluated with a computed analysis of preoperative and postoperative panoramic radiographs. A subjective and clinical radiographic evaluation of the healing process also was performed.

RESULTS

Uneventful healing and spontaneous filling of the residual cavities was obtained in all cases. The computed analysis of the postoperative radiographs showed mean values of reduction in size of the residual cavity of 12.34% after 6 months, 43.46% after 12 months, and 81.30% after 24 months. The increase in bone density was 37% after 6 months, 48.27% after 12 months, and 91.01% after 24 months.

CONCLUSION

Spontaneous bone regeneration can occur in large mandibular cysts without the aid of any filling materials. This simplifies the surgical procedure, decreases the economic and biologic costs, and reduces the risk of postoperative complications.