The hydroxylapatite-bone interface: 10 years after implant installation.

Reconstruction of a severely atrophied maxilla by sinus augmentation with a mixture of hydroxylapatite (HA) granules and autologous cancellous bone is claimed to be a predictable means to facilitate implant placement. To the authors' knowledge, this is the first human histological case report of plasma-sprayed HA-coated implants being loaded after sinus augmentation was performed with a mixture of HA granules and autologous bone. A patient gave consent for post-mortem analysis of his upper jaw, Ten years after successful reconstruction of his maxilla and functional implant loading, the region of augmentation showed stable contours both radiographically and histologically. In 10 years, the granules had only minimally degraded. HA granules outlined the grafted area to protect it against resorption. The plasma-sprayed HA coating on the dental implant was intact, showing 48% contact with the surrounding bone.

A clinical evaluation of 76 implant-supported superstructures in the composite grafted maxilla.

The aim of the study was to evaluate the material behaviour and nature of implant-supported superstructures in function. A total of 37 overdentures, 26 fixed partial and 13 fixed full dentures with a mean lifetime of 40 months were clinically evaluated in relation to damage, occlusion and articulation, parafunction, retentive devices, hygiene and speech problems. In general 70% of all superstructures were damaged. Fixed partial dentures were significantly less damaged than overdentures and fixed full dentures (P<0.001). A significant high percentage of newly gained parafunction was found (P<0.05).

Peri-implant tissue health in reconstructed atrophic maxillae--report of 88 patients and 470 implants.

The aim of this study was to evaluate the soft-tissue health around 470 implants placed in the upper jaw of 88 patients with severe maxillary atrophy. All patients underwent a reconstruction procedure which included a composite bone grafting from the iliac crest to the maxillary sinus. Evaluation was performed at a mean implant lifetime of 21.6+/-10.9 months. The following parameters were used: probing depth, plaque-, gingival-, bleeding index and width of the buccal keratinized mucosa. They were calculated as means for each implant and related to the type of superstructure and the thickness of the original sinus floor. (higher or lower than 5 mm). A high percentage of bleeding on probing was observed in obviously clinically healthy peri-implant pockets. Bleeding on probing and deeper probing depth were especially observed in the group with severe maxillary atrophy (less than 5 mm initial height of the sinus floor.) There was a significant increase in mean peri-implant probing depth and gingiva index in overdentures versus fixed bridges. No differences were observed with respect to the width of the keratinized buccal mucosa. It was concluded that implants in the reconstructed maxilla and supporting overdentures had a higher risk for bone loss, based on the worse peri-implant tissue health observed.

Dental implants in the atrophic maxilla: measurements of patients' satisfaction and treatment experience.

Maxillary bone reconstruction in combination with placement of dental implants is a treatment modality reported since 1980 for patients suffering from maxillary atrophy and difficulties with wearing removable prosthesis. This study reports on patient experience and satisfaction among 88 consecutive patients concerning surgical and prosthetic aspects of their treatment. A questionnaire was used to gather the data. Patient satisfaction was measured on a scale from 1 to 5 (1 = bad/few, 5 = very good/much). The satisfaction index with regard to the total treatment was 4.1 +/- 0.9. A total of 90% of the patients responded that they would go through the treatment again or recommend the treatment to a friend if necessary. The post-operative pain index scored 2.6 +/- 1.2. The acceptation of the post-operative pain at the crista iliaca was 86.1% and of the maxilla 89.9%. It is concluded that the results of measurements of patient satisfaction after maxillary bone reconstruction in combination with placement of dental implants were acceptable.

Survival of cylindrical implants in composite grafted maxillary sinuses.

PURPOSE: This retrospective study investigated the survival of dental implants placed in the maxilla after composite grafting of the sinus and an average of 55 months of loading. PATIENTS AND METHODS: Maxillary sinuses of 88 patients were grafted with autogenous cancellous bone combined with dense hydroxyapatite particles. After an average healing period of 3.4 months, hydroxyapatite-coated titanium endosseous implants were placed. A total of 388 implants were placed in grafted sinus floors, and 82 were placed in onlay grafted nonsinus position in the canine region. The implants were loaded with overdentures and fixed bridges 4 months (mean) after implantation, with a follow-up for a mean of 55 months. RESULTS: The cumulative implant survival was calculated according to the Kaplan-Meier method. Implant survival from the time of loading was 89% in full reconstructed cases and 90% in partially edentulous cases. The overall cumulative implant survival rate, including the loss in the surgical stage, was 82%. CONCLUSION: Implant loss in composite grafted maxillae after 70 months of follow-up was similar to loss in nongrafted maxillae.

[Five-year evaluation of implants in the resorbed maxilla]. / Vijfjaarsoverleving van implantaten in de geresorbeerde bovenkaak.

The survival of implants placed in the resorbed maxillae was investigated. Both edentulous and partially edentulous patients were evaluated including those who underwent 'sinus lift' procedures. The group of patients with a sinus floor augmentation showed a five-year cumulative survival rate varying between 100% for fixed bridges on implants in the partially edentulous maxillae and 75.6% for implants under overdentures placed in severely resorbed edentulous maxillae. It is concluded that placement of implants in the augmented sinus-floor is justified, if the patient is well informed. The procedure can provide a good solution for the prosthetic problems of patients with a resorbed maxilla.

Perioperative morbidity in maxillofacial orthopaedic surgery: a retrospective study.

The data of 2049 patients, who underwent maxillofacial orthopaedic surgery, were retrospectively analysed for major intra- and immediate postoperative complications. Immediate life-threatening complications were very rare. They can in most cases be avoided by good anaesthetic and surgical techniques and adequate postoperative care. The most frequently encountered problem in maxillary surgery is excessive blood loss, whilst a compromised airway due to swelling is the most frequent complication in mandibular surgery. Good co-operation between anaesthetist and surgeon is essential to prevent major intraoperative and immediate postoperative problems.

[The atrophic maxilla. Rehabilitation by bone reconstruction, implants and permanent or removable dentures]. / De geresorbeerde bovenkaak. Rehabilitatie met behulp van botreconstructie, implantaten en vaste of uitneembare prothetische voorzieningen.

Maxillary bone reconstruction in combination with placement of endosseous dental implants is a new treatment modality for patients suffering from maxillary atrophy and difficulties with wearing removable prosthesis. Among 88 patients the experiences with and their satisfaction at parts of the treatment were investigated. Patients could express their appreciation in a 1-5 scale (1 = bad, 5 = good). The satisfaction at the total treatment was given the mean figure 4.1 +/- 0.9. Ninety percent of the patients would go through the treatment again when necessary.

Simultaneous placement of endosteal implants and mandibular onlay grafting for treatment of the atrophic mandible. A preliminary report.

A method of placing two endosteal implants with simultaneous bone grafting to the anterior mandible is described. This technique is simple to use, has minimal morbidity, and has produced good preliminary results. Retrospectively, 18 patients with a total of 36 implants were reviewed. An implant success rate of 91.6% was seen at a mean follow-up time of 17 months after loading with an implant-supported, soft-tissue-borne overdenture.

Sagittal split advancement osteotomies stabilized with miniplates. A 2-5-year follow-up.

Skeletal stability, temporomandibular joint (TMJ)-function, and inferior alveolar nerve function were evaluated in 103 patients with mandibular hypoplasia who were treated with bilateral sagittal split osteotomies to advance the mandible. Stable internal fixation was obtained with miniplates and four monocortical screws. The follow-up period was at least 24 months (average: 32 months; maximum: 60 months). The average B-point advancement was 5.85 mm. Ninety-three patients of 103 (90.3%) had no appreciable relapse at B-point. Eight (7.7%) patients had relapse because of condylar resorption. Maximum mouth opening decreased an average of 1 mm. Sixty-eight percent of the patients with preoperative TMJ-dysfunction symptoms reported improvement or resolution of their symptoms. Sixteen percent experienced worsening of their TMJ symptoms. Permanent neurosensory deficits were identified in five patients (five sides).

A preventive mucosal flap technique for use in implantology.

A flap technique designed for use in dental implantology is described. This technique creates a more homogeneous mucosa around the implants and reduces its thickness to prevent the introduction of deep mucosal pockets around the implants. The technique results in the preservation of a maximum of fixed mucosa and a shallow pocket next to the implant, which aids in optimizing oral hygiene and prognosis. The technique can be performed at the time of implant placement. The flap covers the implants completely and closes the wound primarily. This technique was compared to a conventional flap technique and was clinically found to give significantly better results.

Long-term stability after inferior maxillary repositioning by miniplate fixation.

Nineteen patients underwent Le Fort I osteotomy and inferior maxillary repositioning. Miniplates were used to maintain the maxilla in its new position. The patients were followed from 12 to 58 months, postoperatively. Fourteen patients were considered to be stable over the long term. Five patients had a long-term relapse of more than 30%. A tendency towards greater relapse was seen in patients with more than 5 mm inferior repositioning, and in patients who had concurrent segmental osteotomies of the maxilla. In spite of the use of miniplates, there continues to be an element of unpredictability with regard to vertical relapse after inferior maxillary repositioning, and this may be related to soft-tissue influences.

Composite grafting of the maxillary sinus for placement of endosteal implants. A preliminary report of 48 patients.

The maxillary sinuses in 48 patients were grafted with dense, non-resorbable hydroxylapatite (HA) particles combined with autologous, cancellous bone. After 3 months of healing, HA-coated titanium endosteal implants were placed in the maxilla, and following an additional 3-5 month healing period, the dentitions were restored with various prostheses. Of the 267 maxillary implants placed, 18 (6.4%) failed. Thirteen (6.4%) of the 203 implants placed in the grafted floor of the sinus failed, and 5 (7.8%) of the 64 implants placed in the anterior maxilla failed. Simultaneous lateral and anterior onlay grafting of the alveolar process with the same composite graft material was required in 36 (75%) patients because the width of the alveolar process was considered insufficient for placement of endosseous implants. The mean follow-up period was 17 months (range 12-32). Results from this preliminary study indicate that composite grafting of the maxillary sinus with onlay grafting of the alveolar ridge will provide the bony structure necessary for placement of endosseous implants. Further follow-up of these patients is necessary to determine the long-term stability of this technique; however, these results are promising.

Surgical orthodontic treatment of anterior skeletal open bite using small plate internal fixation. One to five year follow-up.

Thirty-eight patients with skeletal open bite were studied retrospectively to assess stability of surgical-orthodontic treatment when small plate internal fixation was used. 86% of the sample population showed stable clinical results. Follow-up was from 1-5 years. Only 1 patient experienced skeletal relapse (3%) and 5 patients (13%) dento-alveolar relapse. Fifty percent of relapses were due to transverse relapse of orthodontically expanded maxillary arches. No relapse was seen with surgically assisted orthodontic expansion or surgical expansion at the time of osteotomy. Stable results can be achieved in treating skeletal open bite when small plate internal fixation is used and proper consideration given to the cause of skeletal open bite when planning treatment.

[The role of the dentist in the prevention and early detection of oral carcinoma]. / Mondkanker. De rol van de tandarts bij de preventie en vroegtijdige herkenning van plaveiselcelcarcinomen.

Based on data derived from the Arnhem Regional Health area, the number of patients with a primary oral squamous cell carcinoma in the Dutch population has been estimated to be approximately 400 per year. Given the population of almost 15 million, the incidence can be estimated to be 2.8 per 100,000. The role of the dentist in the prevention and early detection of cancer of the mouth is discussed. The need for regular check-ups on the target group of patients, being heavy alcohol consumers and smokers, is emphasized. Simple methods for elimination of local irritating factors are recommended.

Late management of secondarily grafted clefts.

34 patients (40 sides) received alveolo-palatal bone grafts for closure of the residual cleft, thus guiding a lateral incisor or canine into the arch. Long-term follow-up shows that in 41% of the patients uninterrupted arches were achieved with a normal relationship by orthodontic treatment only. 38% needed segmental osteotomies to eliminate the edentulous space, and in only 20% were bridges made to restore the dental arch. 9 (25%) patients still required a Le Fort I advancement osteotomy, despite optimal orthodontic treatment. The use of segmental osteotomies for eliminating edentulous spaces in cleft palate patients is discussed, and their advantage in relation to nasal base support is emphasized. It should be the aim to achieve in every cleft palate patient a complete archform without the need for bridges or removable prostheses. A rational orthodontic-surgical approach to the cleft, lip and palate patient is suggested with respect to naso-maxillary growth and development.

Management of malunited mandibular condylar fractures.

The non-surgical treatment of mandibular condylar fractures, may occasionally result in articular imbalance and temporomandibular joint dysfunction. This may be attributed to condylar head displacement and resorption, resulting in a shortened vertical ramus and lost posterior vertical facial height. Restoring the vertical ramus height is essential in the treatment of such dysfunction, and may be accomplished by unilateral, or bilateral ramus osteotomies. Four examples of patients treated with mandibular ramus osteotomies to restore vertical ramus height, with subsequent improvement in occlusal balance and function are presented. The use of the sagittal split mandibular osteotomy and the external vertical ramus osteotomy, stabilized with small osseous plates, and monocortical screws, is discussed.

The hydroxylapatite-bone interface. Studies on a human biopsy.

Augmentation of the mandible with HA and cancellous bone appears to be a clinically stable and reliable procedure. A human biopsy, taken after 16 months, shows a mature bone frame embedding HA particles and a stable HA-bone interface. Minimal biodegradation was observed in the subperiosteal layer.