Residual Alveolar Cleft Research Articles

A 3-Dimensional Evaluation of Bone Density in Alveolar Cleft Grafting Methods: Bone Substitutes Versus Autologous Bone.

Secondary alveolar cleft repair using autologous bone graft is currently the gold standard in treating residual alveolar clefts. Despite its effectiveness, this technique is still burdened by several withdrawals, mostly related to donor site morbidity. To decrease disadvantages for patients, numerous attempts in the literature regarding bone substitutes have been described. The aim of this study is to compare the viability of bovine-based replacement bone material with respect of autologous bone graft in alveolar cleft reconstruction, through 3-dimensional alveolar cleft segmentation and bone density evaluation from preoperative and postoperative cone-beam computed tomography. A retrospective cohort study of 10 patients who underwent surgical procedure for alveolar cleft grafting at Sant'Orsola Malpighi University Hospital of Bologna from December 2012 to December 2016 was undertaken. Five patients received autologous bone graft and 5 a bovine bone substitute graft. Preoperative and immediate postoperative orthopanoramic x-rays were recorded. Cone-beam computed tomography scans have recorded both pre and postoperatively. Volumetric evaluation on 3-dimensional cone-beam computed tomography images was performed. Alveolar clefts repaired using substitute bovine bone/biological membrane scaffold had a mean fill of 69.00% of total cleft volume, while this figure was of 67.07% with autologous bone grafting. The immediate postoperative course and subsequent discharge were uneventful for both groups, with a difference in timing. The cost of substitute bovine bone was offset by cost savings associated with a reduction in operative and postoperative and hospitalization time. Bone substitutes showed to be a promising solution in alveolar cleft grafting.

Secondary Alveolar Bone Grafting in Patients with Unilateral and Bilateral Complete Cleft Lip and Palate: A Single-Institution Outcomes Evaluation Using Three-Dimensional Cone Beam Computed Tomography.

Secondary alveolar bone grafting of autologous bone from the iliac crest is a widely accepted modality for repair of residual alveolar cleft in patients with mixed dentition with previously repaired complete cleft lip and palate. There remains debate regarding surgical timing and preoperative, perioperative, and postoperative management of these cases. This retrospective study reviewed patient demographic information in addition to preoperative, perioperative, and postoperative course to evaluate how patient and practice factors impact graft outcomes as assessed by three-dimensional cone beam computed tomographic evaluation at the 6-month postoperative visit. On univariate analysis, age at operation older than 9 years, history of oronasal fistula, history of cleft lip or palate revision, and history of international adoption were all found to significantly increase likelihood of graft failure (p < 0.05). On multivariate analysis, age older than 9 years was found to be the single most significant predictor of graft failure (p < 0.05). There was no significant difference in graft outcomes between patients with unilateral or bilateral cleft lip and palate, and no single variable was found to significantly correlate to increased complication rates. The graft success rate overall of the authors' practice was 86.2 percent, with a complication rate of 7.7 percent. Secondary alveolar bone grafting is an integral part of the cleft lip and palate surgical treatment series; this study identified several outcome predictors for both graft failure and adverse events, the most significant of which was age at operation. Although the mixed dentition phase often extends to 12 years of age, it is recommended that bone grafting be performed before 9 years of age to optimize outcomes. Risk, III.

A Novel and Practical Protocol for Three-Dimensional Assessment of Alveolar Cleft Grafting Procedures.

To evaluate the reproducibility and accuracy of a new, easy-to-use volumetric assessment of the alveolar cleft. Twelve cone-beam computed tomography (CBCT) datasets of patients with a unilateral cleft lip, alveolus, and palate were evaluated by two investigators. Residual alveolar cleft calcified volume one year after surgery was analyzed by using standardized landmarks to determine the borders of the cleft defect and semi-automatically segment the alveolar cleft defect. The Dice-coefficient between observers for the segmented preoperative alveolar cleft defect was 0.81. Average percentage of residual alveolar cleft calcified material was 66.7% one year postoperatively. This study demonstrates a reliable and practical semi-automatic three-dimensional volumetric assessment method for unilateral clefts using CBCT.

Non-prosthetic treatment using segmental osteotomy and bone grafting in a patient with cleft lip and palate

This case report aimed to present the course of surgically combined comprehensive orthodontic treatment of a male adult with cleft lip and palate, showing a left alveolar cleft, lateral deviation of the major segment of the maxilla, and palatal transposition of the lateral incisor. Preoperatively, the midline of the upper central incisors was shifted by 7.0 mm to the right, the right lateral incisor showed palatal transposition, and the residual alveolar cleft was 6.5 mm. Segmental Le Fort I osteotomy of the major segment, and simultaneous bone grafting into the extended alveolar bone and former cleft region were performed at 18 years and 4 months of age. Thus, midline correction, alignment of the right lateral incisor, and cleft closure were achieved; no further prosthetic treatment was required.

Safety and feasibility study of using polyphosphate (PolyP) in alveolar cleft repair: a pilot study

BackgroundBone grafting is an important surgical procedure to reconstruct alveolar bone defects in patients with cleft lip and palate. Polyphosphate (PolyP) is a physiological polymer present in the blood, primarily in platelets. PolyP plays a role as a phosphate source in bone calcium phosphate deposition. Moreover, the cleavage of high-energy bonds to release phosphates provides local energy necessary for regenerative processes. In this study, polyP is complexed with calcium to form Calcium polyP microparticles (Ca-polyP MPs), which were shown to have osteoinductive properties in preclinical studies. The aim of this study was to evaluate the feasibility, safety, and osteoinductivity of Ca-polyP MPs, alone or in combination with BCP, in a first-in-human clinical trial.MethodsThis single-blinded, parallel, prospective clinical pilot study enrolled eight adolescent patients (mean age 18.1: range 13–34 years) with residual alveolar bone cleft. Randomization in two groups (four receiving Ca-polyP MPs only, four a combination of Ca-polyP MPs and biphasic calcium phosphate (BCP)) was performed. Patient follow-up was 6 months. Outcome parameters included safety parameters and close monitoring of possible adverse effects using radiographic imaging, regular blood tests, and physical examinations. Osteoinductivity evaluation using histomorphometric analysis of biopsies was not possible due to COVID restrictions.ResultsDue to surgical and feasibility reasons, eventually, only 2 patients received Ca-polyP MPs, and the others the combination graft. All patients were assessed up to day 90. Four out of eight were able to continue with the final assessment day (day 180). Three out of eight were unable to reach the hospital due to COVID-19 restrictions. One patient decided not to continue with the study.None of the patients showed any allergic reactions or any remarkable local or systematic side effects. Radiographically, patients receiving Ca-polyP MPs only were scored grade IV Bergland scale, while patients who got the BCP/Ca-polyP MPs combination had scores ranging from I to III.ConclusionsOur results indicate that Ca-polyP MPs and the BCP/Ca-polyP MPs combination appear to be safe graft materials; however, in the current setting, Ca-polyP MPs alone may not be a sufficiently stable defect-filling scaffold to be used in alveolar cleft repair.Trial registrationIndonesian Trial Registry under number INA-EW74C1N by the ethical committee of Faculty of Medicine, Hasanuddin University, Makassar, Indonesia with code number 1063/UN4.6.4.5.31/PP36/2019.

Adult patient with bilateral cleft lip and palate treated using bone graft followed by lateral distraction: A case report

This is a case report of comprehensive treatment describing the management of an adult patient with bilateral cleft lip and palate who showed severe maxillary transverse deficiency caused by bilateral alveolar clefts. Since the residual alveolar clefts were extremely wide, we performed bone graft into the alveolar clefts first and then expanded the asymmetrically narrowed maxilla by asymmetric transverse distraction osteogenesis, in which an incision for osteotomy was made at the repaired bone bridge. The treatment accomplished successful reconstruction of the dental arches and occlusion. Aesthetic improvement was noted, with no discernible post-treatment relapse of occlusion after two years’ retention.

Grafting of Alveolar Cleft Defects in Preparation for Endosseous Dental Implant Placement and Orthodontic Tooth Movement

Prosthodontic rehabilitation of patients with edentulous sites secondary to cleft palate has shown a paradigm shift towards implant placement in skeletally mature patients. Patients with residual alveolar cleft defects after secondary grafting at the optimal age of 8-11 years old have presented with persistent defects precluding implant placement. The purpose of this article is to revisit an approach to augmentation bone grafting of the residual maxillary alveolar cleft defect in preparation for endosseous dental implant placement.

Techniques to Improve Reliability and Predictability of the Dorsal Pedicled Tongue Flap in Closure of Palatal Defects and Oronasal Fistulae.

Despite the improvement in surgical techniques in cleft palate surgery, oronasal fistulas continue to remain a challenge, usually the result of residual palatal and alveolar clefts and post-palatoplasty defects. The tongue flap is an extremely versatile, sturdy, reliable and efficient means of closure of anterior as well as posterior, unilateral and bilateral palatal defects, effectively functionally obliterating the oronasal communication, owing much of its success to its highly vascular structure, good mobility, texture match, central location and low donor site morbidity. However, it has a few drawbacks. Flap dehiscence and detachment during the early postoperative period is a troublesome complication owing to tongue movements during normal activities such as speaking, swallowing, yawning and coughing. This article describes some of the methods which can be used to effectively alleviate these shortcomings. A protocol of immobilizing the tongue by tethering it to the maxillary teeth for the 3-week postoperative period, and also maintaining the patient on nasogastric feeding, until the patient is taken up for surgical separation the pedicle, was employed in all patients in this case series. There was a successful and predictable take of the tongue flap at the donor site, namely the palatal/oronasal fistula with its successful closure, in all the patients. Treatment of the oronasal fistula using a two-layer closure using the nasal mucoperiosteum together with an anteriorly based dorsal tongue flap is an easy and efficient method, whose reliability can be further increased by avoiding a common complication, namely tongue flap detachment in the postoperative period brought on by movements of the tongue, by immobilizing the tongue by tethering it to the maxillary teeth and also maintaining the patient on nasogastric feeding for the 3-week postoperative period.

Cortical Bone Graft and GTR Membrane as "Ceiling Effect" in Alveolar Bone Grafting.

In orofacial cleft deformity cases, bone grafting is a very essential step in reconstruction of the residual alveolar cleft defect. Though various authors have put forth different techniques and graft sources for alveolar bone grafting, at our center, we have used iliac crest as the graft source and cortical bone graft with GTR membrane as "ceiling effect". We have evaluated a series of cases of secondary alveolar bone grafting done with this technique by same surgeon at our center and have found great success. In this clinical paper, we describe our surgical technique and also the key points from surgeons experience to ensure a better result.

A Case Report of Multidisciplinary Treatment of an Adult Patient with Bilateral Cleft Lip and Palate

This is a case report about the successful orthodontic treatment of a bilateral cleft lip and palate patient by using a combination of bone grafting and subsequent prosthodontic rehabilitation. An adult patient with a bilateral cleft lip and palate presented with a concave profile, anterior and lateral crossbite, a markedly deep overbite, and residual bilateral alveolar clefts. His jaw movement patterns were unstable and irregular due to his collapsed bite. Orthodontic treatment with bilateral bone grafting improved his concave profile by downward and backward rotation of the mandible within the freeway space, and optimum occlusion and functionally stable and smooth jaw movements were obtained. After a 6-year retention period, no skeletal relapse could be detected, and his occlusal stability was satisfactory.

Mid versus late secondary alveolar cleft grafting using iliac crest corticocancellous bone graft.

Mid-secondary alveolar cleft repair performed at ages 9-12, in the mixed dentition stage, prior to eruption of the permanent canine, is generally accepted as the ideal time for residual alveolar cleft closure in cleft lip and palate cases with a cleft alveolus. In our study, four cases of mid-secondary and five cases of late-secondary alveolar cleft grafting were carried out using iliac crest corticocancellous bone graft. Clinical defect closure and radiographic bone fill were compared. All the nine cases performed in the two different age groups showed excellent results, clinically, with complete closure of the cleft defect and achievement of continuity of the dental arches. One case was planned for a two-stage procedure owing to the large bilateral maxillary defects. Good bone fill was visualized radiographically in all nine cases. Precise timing for undertaking alveolar cleft repair may not be all that crucial for a successful alveolar cleft grafting procedure.

Alveolar bone graft with Platelet Rich Plasma in cleft alveolus

IntroductionCleft of the lip, palate and alveolus are the commonest congenital anomaly to affect the orofacial region. Currently, there is great interest in the alveolar bone grafting procedures that involve use of platelet-rich-plasma (PRP), to enhance bone formation and specifically to promote bone graft healing. Materials and methods20 patients with residual alveolar cleft, in the age group of 9–29 years, having unilateral or bilateral cleft lip and palate were selected. They were randomly assigned in either group A (with PRP) or group B (without PRP). ResultsPrimary healing was observed in 90% patients in group A. Secondary healing was seen in 30% patients in group B. There was no graft rejection in group A but was seen in one patient (10%) in group B. Pain and swelling persisted longer in group B then group A. Bone grafts with added PRP presented with increased bone density (1028.00 ± 11.30 HU) in comparison to grafts without PRP (859.50 ± 27.73 HU) at end of 6-month postoperative. However, the mean bone density (as determined by the Dentascan image analyzer software) was 1.04 times more in the PRP group than non PRP group at 3-month and 1.2 times more at 6 months. ConclusionWe conclude that on preliminary investigations, PRP seems to enhance bone formation in alveolar clefts when admixed with autologous cancellous bone harvested from the iliac crest.

Secondary alveolar bone grafting: Radiographic and clinical evaluation.

Introduction:Secondary bone grafting of maxilla and residual alveolar clefts at the stage of transitional dentition was first introduced by Boyne and Sands. The aim of this prospective case control study was to clinically and radiologically evaluate the success rate of anterior iliac crest graft in primary alveolar cleft.Methods and Material:In this study we evaluated 10 patients who underwent secondary alveolar bone grafting for various types of cleft palate with autologous iliac crest graft. Type of septum measured radiologically was taken as the outcome measure.Results:Postoperative radiographic evaluation revealed Type I inter alveolar septum in 7 cases (87.5%), with complete unilateral cleft lip, palate and alveolus. Non-eruption of canine occurred in 5 patients (50%). Periodontal Examination revealed presence of pocket formation (less than 4 mm) and Grade II mobility in 2 cases (20%).Conclusions:In conclusion, secondary alveolar bone grafting done during the time of transitional dentition, before the eruption of permanent canine is an excellent treatment modality.

Ｌｅ Ｆｏｒｔ Ｉ型骨切り術により幅の広い顎裂を閉鎖した成人片側性口唇口蓋裂の１症例

The residual wide alveolar cleft often causes potential risk in bone grafting and prosthodontic treatment for cleft lip and palate patients. While performing cleft reduction, maxillary advancement is required because closure of the cleft space itself with orthodontic/orthognathic treatment will result in a crossbite. In this paper, we report the case of a 21-year 4-month old male with left cleft lip and palate. The patient had undergone orthodontic treatment once at another institute, and he visited our Orthodontic Clinic at the University Hospital of Dentistry, Tokyo Medical and Dental University with a chief complaint of residual cleft space. Overjet and overbite were both 2.0 mm and the intercuspation of the buccal segments was optimal. However, the residual cleft space was 14.5 mm with no history of bone grafting. The right maxillary lateral incisor lacked congenitally, and the left lateral incisor was a lingually malpositioned conical tooth. The midline of the maxillary had right deviation of 6.5 mm. A multibracket appliance was used for the presurgical orthodontic treatment and a Le Fort I osteotomy was performed when the patient was 22-years and 4-months old. During the operation, the left maxillary lateral incisor in the cleft area was extracted. A Twin-Track device was placed along with the maxillary dental arch to guide the surgical movement of the alveolar segments into place. After complete cleft closure was achieved along this splint, maxillary segments were fixed using mini-plates and bone grafting was simultaneously performed. After 2 years of post-surgical orthodontic treatment, acceptable occlusion was achieved and no further prosthetic treatment was required.

Intraoral Distraction of Segmental Osteotomies and Miniscrews in Management of Alveolar Cleft

Management of a wide alveolar cleft and alveolar bone graft failure is among the most difficult tasks for both surgeon and orthodontist. This article aims to introduce the techniques of intraoral distraction of segmental osteotomy for solving a wide alveolar cleft, and orthodontic management with miniscrews for solving alveolar bone graft failure; and also to evaluate the feasibility and clinical results of moving teeth into alveolar clefts. Interdental distraction osteogenesis was performed to minimize the alveolar cleft before alveolar bone grafting in 21 patients whose alveolar cleft was wider than a maxillary canine. All clefts were successfully approximated, and the 4- to 5-year results were shown to be stable. In addition, orthodontic protraction of the buccal teeth by using miniscrews as a temporary anchorage device was performed in 13 cases to minimize and/or eliminate the residual bony bridge or alveolar cleft after the previous failure of an alveolar bone graft. The buccal teeth were protracted with intermittent light continuous force. The results revealed that the residual bony bridges or alveolar clefts were minimized and that the space of the cleft was completely closed. The periodontal apparatus of the teeth that were moved into the residual bony bridge or alveolar cleft remained similar before and after the treatment. The orthodontic tooth movement into a residual alveolar cleft is clinically feasible in certain circumstances. However, the long-term status of the periodontal apparatus of the teeth that were moved into the alveolar cleft should be monitored.

Alveolar bone grafting.

In patients with cleft lip and palate, bone grafting in the mixed dentition in the residual alveolar cleft has become a well-established procedure. The main advantages can be summarised as follows: stabilisation of the maxillary arch; facilitation of eruption of the canine and sometimes facilitation of the lateral incisor eruption; providing bony support to the teeth adjacent to the cleft; raising the alar base of the nose; facilitation of closure of an oro-nasal fistula; making it possible to insert a titanium fixture in the grafted site and to obtain favourable periodontal conditions of the teeth within and adjacent to the cleft. The timing of the ABG surgery take into consideration not only eruption of the canine but also that of the lateral incisor, if present. The best time for bone grafting surgery is when a thin shell of bone still covers the soon erupting lateral incisor or canine tooth close to the cleft.

Alveolar bone grafting

In patients with cleft lip and palate, bone grafting in the mixed dentition in the residual alveolar cleft has become a well-established procedure. The main advantages can be summarised as follows: stabilisation of the maxillary arch; facilitation of eruption of the canine and sometimes facilitation of the lateral incisor eruption; providing bony support to the teeth adjacent to the cleft; raising the alar base of the nose; facilitation of closure of an oro-nasal fistula; making it possible to insert a titanium fixture in the grafted site and to obtain favourable periodontal conditions of the teeth within and adjacent to the cleft. The timing of the ABG surgery take into consideration not only eruption of the canine but also that of the lateral incisor, if present. The best time for bone grafting surgery is when a thin shell of bone still covers the soon erupting lateral incisor or canine tooth close to the cleft.

Poster 166: Esthetic and Functional Reconstruction Using Implants in a Patient With Alveolar Clefts

Statement of the ProblemA residual alveolar cleft represents an obstacle for rehabilitation of a dental arch. As a solution, implants with an autogenous bone graft have been suggested for dental reconstruction in alveolar clefts patients. Insufficient interdental alveolar bone height and aesthetic issues seem to be limiting factors in the clinical use of this procedure. This report suggested that superior results can be obtained for esthetic and functional reconstruction using implants with alveolar clefts.Materials and MethodsThe patient was born with a congenital bilateral complete cleft and palate. A closure of the left cleft lip was completed at 4 months of age, the right was completed at 8 months, and the palatal cleft was closed at 1 year 9 months. The patient underwent right alveolar bone grafting at the age of 22 years and left alveolar bone grafting at 23 years. After bony bridge formation became a base, the patient underwent veneer grafting after 6 months to insert implants. The implants were inserted with bone grafting after 3 months.Method of Data AnalysisFindings after surgery demonstrated well maintained interdental bony height and width in the premaxilla. The results indicated that osseointegrated implants combined with bone grafting are more reliable than conventional procedures for occlusal reconstruction in patients with alveolar cleft.ResultsFor general treatment of alveolar cleft, we obtained superior results in respect esthetics and configuration. The results here suggested that the placement of implants can be successfully carried out in grafted alveolar clefts.ConclusionPlacement of endosseous implants in grafted alveolar clefts. Statement of the ProblemA residual alveolar cleft represents an obstacle for rehabilitation of a dental arch. As a solution, implants with an autogenous bone graft have been suggested for dental reconstruction in alveolar clefts patients. Insufficient interdental alveolar bone height and aesthetic issues seem to be limiting factors in the clinical use of this procedure. This report suggested that superior results can be obtained for esthetic and functional reconstruction using implants with alveolar clefts. A residual alveolar cleft represents an obstacle for rehabilitation of a dental arch. As a solution, implants with an autogenous bone graft have been suggested for dental reconstruction in alveolar clefts patients. Insufficient interdental alveolar bone height and aesthetic issues seem to be limiting factors in the clinical use of this procedure. This report suggested that superior results can be obtained for esthetic and functional reconstruction using implants with alveolar clefts. Materials and MethodsThe patient was born with a congenital bilateral complete cleft and palate. A closure of the left cleft lip was completed at 4 months of age, the right was completed at 8 months, and the palatal cleft was closed at 1 year 9 months. The patient underwent right alveolar bone grafting at the age of 22 years and left alveolar bone grafting at 23 years. After bony bridge formation became a base, the patient underwent veneer grafting after 6 months to insert implants. The implants were inserted with bone grafting after 3 months. The patient was born with a congenital bilateral complete cleft and palate. A closure of the left cleft lip was completed at 4 months of age, the right was completed at 8 months, and the palatal cleft was closed at 1 year 9 months. The patient underwent right alveolar bone grafting at the age of 22 years and left alveolar bone grafting at 23 years. After bony bridge formation became a base, the patient underwent veneer grafting after 6 months to insert implants. The implants were inserted with bone grafting after 3 months. Method of Data AnalysisFindings after surgery demonstrated well maintained interdental bony height and width in the premaxilla. The results indicated that osseointegrated implants combined with bone grafting are more reliable than conventional procedures for occlusal reconstruction in patients with alveolar cleft. Findings after surgery demonstrated well maintained interdental bony height and width in the premaxilla. The results indicated that osseointegrated implants combined with bone grafting are more reliable than conventional procedures for occlusal reconstruction in patients with alveolar cleft. ResultsFor general treatment of alveolar cleft, we obtained superior results in respect esthetics and configuration. The results here suggested that the placement of implants can be successfully carried out in grafted alveolar clefts. For general treatment of alveolar cleft, we obtained superior results in respect esthetics and configuration. The results here suggested that the placement of implants can be successfully carried out in grafted alveolar clefts. ConclusionPlacement of endosseous implants in grafted alveolar clefts. Placement of endosseous implants in grafted alveolar clefts.

The Role of Functional Orthodontic Stress on Implants in Residual Alveolar Cleft

The most widely accepted protocol for alveolar cleft reconstruction is repair during the mixed dentition stage (age, 9 to 11 years), before eruption of the canine teeth. Alveolar bone grafting should not be considered as an isolated therapy but always as an integrated part of comprehensive orthodontic treatment. The authors evaluate the results of transitional secondary osteoplasty, comparing the use of autogenous cancellous bone versus heterogenetic implants, in patients with unilateral complete clefts who did or did not undergo orthodontic treatment. From 1990 to 1994, 48 patients aged between 9 and 11 years with unilateral alveolar cleft underwent alveolar grafting by transitional secondary osteoplasty. In 30 patients (group A), autogenous cancellous bone was used, and in 18 patients (group B), a heterogenetic implant consisting of demineralized bone powder containing bone morphogenetic protein and hydroxylapatite was used. Twenty-two patients in group A and 12 patients in group B underwent orthodontic treatment. After 10 to 12 years of follow-up, the clinical and radiographic examinations revealed that the best alveolar bone repair results were obtained using autologous bone graft in association with orthodontic treatment. Also, in the patients who underwent heterogenetic implantation, the orthodontic treatment clearly improved the quality of the osteoplasty. The essential conditions for a successful osteoplasty include meticulous operative technique and orthodontic treatment. The latter plays an essential role at several stages of development in children with clefts. The "functional stress" on the autologous or heterogenetic implant exerts a decisive influence on the quality and volume of the osteoplasty, preventing progressive resorption.

顎裂部自家腸骨海綿骨細片移植術術後の骨吸収について―梨状孔下縁形態における評価―

Grafting of autogenous particulate cancellous bone and marrow to residual alveolar clefts in patients with cleft lip and palate is a well-established procedure for non-prosthetic rehabilitation with canine eruption into the grafted bone or for maintenance treatment after achieving arch alignment. Various analyses of the effect of grafting have been reported, but nearly all previous studies focused on non-prosthetic rehabilitation. The reconstruction of alveolar bone has been evaluated on only intraoral radiographs.We consider the purposes of bone grafting to the alveolar cleft to be not only non-prosthetic rehabilitation, but also correction of anomalies around the nasal cavity. We evaluated the status of bone bridge formation and bone resorption in 146 unilateral clefts of the prepalate and palate, which underwent bone grafting between 1996 and 2000. We also examined factors related to bone anomalies around both the alveolar ridge and the piriform aperture.Our results showed that age at bone grafting had a signifcant influence on resorption. Thus, we consider the time of bone grafting to be very important. Grafting should be done before 11 years of age and eruption of the canines. In addition, orthodontic space closure, which includes tooth root guidance to the grafted bone after alveolar bone grafting, is necessary for bone bridge formation on the piriform aperture side.