Volumetric osseous changes in the completely edentulous maxilla after sinus grafting and lateral bone augmentation: a systematic review.

The aim of this systematic review was to evaluate the volumetric changes associated with different bone grafting techniques in the completely edentulous atrophic maxilla before dental implant placement. A search was performed according to the PRISMA guidelines. A PICO question was formed, and the PubMed, Scopus, Embase, and Cochrane Library databases were searched, covering the period 2000-2018. Relevant data were extracted from the results regarding study population, surgical details, technical information on volumetric data acquirement, and volumetric outcome after bone augmentation procedures before implant placement. Six articles with a combined population of 84 patients were included. All patients had a completely edentulous maxilla, with a crestal horizontal width of <3-4mm or a crestal vertical height of <6-7mm. The iliac bone and ascending ramus were most frequently used as grafts. Five of the six studies reported volumes of sinus inlay graft (SIG) and four reported volumes of lateral bone augmentation (LBA). Radiographic analyses of the augmented areas differed among the studies. Volume loss after bone augmentation procedures ranged from 5% to 50% for SIG and from 5% to 47% for LBA. All surgical augmentation techniques for the edentulous maxilla are prone to resorption; no procedure seemed to be superior, but some interesting observations were made.

Stability, complications, implant survival, and patient satisfaction after Le Fort I osteotomy and interposed bone grafts: follow-up of 5-18 years.

The results of a retrospective study on 24 patients who underwent a Le Fort I osteotomy to improve the condition for implant insertion are presented. They all had an edentulous maxilla, Cawood and Howell class VI. Bone grafts were taken from the anterior or posterior iliac crest and implants were placed between 3 and 6 months after the osteotomy. The follow-up period ranged from 5 to 18 years. Initial complications occurred in seven patients in whom small bony defects were present at the time of the implant insertion procedure. The position of the advanced and downward grafted maxilla remained stable over the years. A total of 135 implants were initially inserted, of which 34 failed over the years. Ten implants were inserted to compensate for lost ones, of which only one failed. The screw implants tended to do better than the cylindrical implants. Two patients lost all implants; they had undergone previous surgery affecting the sinus and were also heavy smokers. The remaining 22 patients were satisfied with their treatment as shown by visual analogue scale scores. The results presented are in keeping with those of other reports and underscore the viability of the procedure.

A randomized clinical trial of biodegradable and titanium fixation systems in maxillofacial surgery.

Biodegradable fixation systems could reduce or delete the problems associated with metallic systems, since removal is not necessary. The aim of this study was to establish the effectiveness and safety of biodegradable plates and screws as potential alternatives to metallic ones. This multi-center randomized controlled trial was conducted from December 2006 to July 2009. Included were patients who underwent mandibular and/or Le Fort I osteotomies and those with fractures of the mandible, maxilla, and zygoma. The patients were assigned to a titanium control group (KLS Martin) or to a biodegradable test group (Inion CPS). The primary outcome measure was 'bone healing 8 weeks post-operatively'. The Intention-To-Treat (ITT) analysis of 113 patients in the titanium group and 117 patients in the biodegradable group yielded a significant difference (p < 0.001), primarily because in 25 patients (21%) who were randomized to the biodegradable group, the surgeon made the decision to switch to titanium intra-operatively. Despite this 'inferior' primary outcome result, biodegradable plates and screws could be safely used when it was possible to apply them. The benefits of using biodegradable systems (fewer plate removal operations) should be confirmed during a follow-up of minimally 5 years (Controlled-trials.com ISRCTN number 44212338).

The effect of a single dose of bupivacaine on donor site pain after anterior iliac crest bone harvesting.

Transplants from the anterior iliac crest are used for most reconstructive procedures in cranio-maxillofacial surgery. The advantages are easy accessibility, the ability to work in two teams and the amount of corticocancellous bone available; disadvantages are postoperative pain and gait disturbances. To reduce donor-site pain, the effect of a single dose of bupivacaine (10 cc of 2.5mg/cc with 1:80.000 epinephrine) was studied. 200 consecutive patients, who underwent anterior iliac crest bone harvesting for reconstructive procedures, were randomly divided into those receiving bupivacaine and those not. They completed a standardized questionnaire. Patients scored the intensity of the pain and difficulties walking at different times with a visual analogue scale. They recorded analgesics used. 98 questionnaires were eligible for analysis. No differences between the bupivacaine and the control group were detected for postoperative pain and gait disturbance. There is no support for administration of a single dose of bupivacaine to reduce pain in the first postoperative days. The surface area of the removed bone had a significant influence on pain and walking; pain is related to the local osseous damage or periosteal stripping rather than to the length of incision or the operation time.

Stabilisation of sagittal split set-back osteotomies with miniplates: a prospective, multicentre study with 2-year follow-up.

The aim of this study was to assess post-operative stability of bilateral sagittal split set-back osteotomies using two miniplates and clinical parameters including nerve function, TMJ function, occlusal relapse and patient satisfaction. The stability was measured on cephalometric radiographs and possible condylar alterations on orthopantomograms. This prospective study implied a 2-year follow-up on a group of 24 patients. The same protocol was used at six participating institutions at which the patients were treated. A stable occlusion without appreciable relapse was seen in 91% after 2-year follow-up. Only two patients in this study had mild occlusal relapse. The mean skeletal horizontal relapse at pogonion of the whole group, after 2 years was 1.1mm and appeared to be directed backwards. At occlusal level, however, the mean relapse was 1.2mm forwards. The function of the inferior alveolar nerve 2 years post-operatively was reported to be normal in approximately 70% of the patients, yet 80% had no complaints about nerve dysaesthesia. In approximately 21% of the patients, signs and symptoms of TMJ dysfunction had disappeared. Another group (10%), however, without pre-operative signs and symptoms of TMJ dysfunction developed these signs or symptoms post-operatively. No condylar remodelling or resorption was seen in this group of patients. The sagittal split set-back osteotomy fixed with miniplates appeared to be a relatively save and reliable procedure giving rise to adequate results and a high degree of patients satisfaction.

Stabilisation of sagittal split advancement osteotomies with miniplates: a prospective, multicentre study with two-year follow-up. Part III--condylar remodelling and resorption.

This prospective study implied a two-year follow-up in a group of patients that underwent a Bilateral Sagittal Split Osteotomy (BSSO) for advancement of the mandible that were treated in seven institutions following the same treatment protocol (using two miniplates). The aim of Part III of this study was to define a Condylar Morphology Scale (CMS) and to analyse radiological changes in the TMJ after BSSO in relation to postoperative relapse and to determine the incidence of morphologic changes and its risk factors. It was concluded that the used 3-point CMS served its purpose well. In eight patients (4%) resorption of the condyle developed postoperatively. The value of preoperative cephalograms to predict condylar alterations appeared to be limited (12% explained variance). Patients treated at a relative low age (< or = 14 years) appeared to be at risk for the occurrence of condylar alterations including resorption. A steep mandibular plane angle and the low facial height ratio (post:ant) were also significantly related to the occurrence of condylar alteration, but the multi variance regression showed that these parameters had only limited value. The occurrence of pain and TMJ sounds in the first few months postoperatively are highly suspicious for condylar changes to occur in the next months.

Stabilisation of sagittal split advancement osteotomies with miniplates: a prospective, multicentre study with two-year follow-up. Part II. Radiographic parameters.

This prospective study implied a two-year follow-up on a group of patients that underwent a Bilateral Sagittal Split Osteotomy (BSSO) for advancement (n=222) of the mandible that were treated in seven institutions following the same treatment protocol. The aim of Part II of this study was to correlate the clinical findings on stability and relapse as reported in Part I (clinical parameters) of this series of articles with the cephalometric findings. The mean skeletal relapse at pogonion of the whole group after two years was 0.9 mm. The clinically stable group, however, had only 0.4 mm relapse, whereas the clinical relapse group showed a mean relapse of 3.3 mm. The findings underline a relationship between the amount of advancement and relapse. The tendency for both, horizontal and vertical movement is the same, i.e., the larger the surgery effect, the larger the relapse. The angle post plane/mandibular plane showed the highest explained variance 9%. Patients with a high mandibular plane angle may be more prone to relapse. The explained variance of all considered prognostic factors together, however, is small (13%). The findings of this study express that patients with a clinical stable occlusion after a BSSO advancement, stabilised with miniplates, have a minimal to no skeletal relapse as measured on the cephalometric radiograms. The clinically non-stable group, however, appeared to have considerable skeletal relapse.

Stabilisation of sagittal split advancement osteotomies with miniplates: a prospective, multicentre study with two-year follow-up. Part I. Clinical parameters.

The principal aim of this study was to assess the postoperative stability of bilateral sagittal split osteotomies (BSSO) using two miniplates. Part I reports on the clinical results including treatment characteristics, nerve functions, TMJ function, occlusional relapse and patient satisfaction. This prospective study evaluated a group of 222 patients who underwent a BSSO for mandibular advancement. The same treatment protocol was used at seven participating institutions at which the patients were treated. A stable occlusion without appreciable relapse was seen in 84% after 2 years of follow-up. A considerable minority (16%) had occlusal relapse. There were no clinical parameters that pointed towards a high risk for relapse except age. The mean operation age of the relapse group was 20.7 years (SD 6.7) and in the stable group 26.1 years (SD 8.2). The function of the inferior alveolar nerve 2 years postoperatively was reported to be normal in approximately 88% of the patients, while 94% had no complaints about nerve dysaesthesia. In approximately 56% of the patients with pre-existing TMJ-dysfunction these signs and symptoms had disappeared. Another group of patients, however, without TMJ-dysfunction preoperatively (22%) developed signs or symptoms of TMJ-dysfunction postoperatively. The sagittal split osteotomy fixed with miniplates appeared to be a relatively safe and reliable procedure giving rise to a high degree of patient satisfaction, despite the fact that some occlusal relapse was seen.