The effect of supportive care in preventing peri-implant diseases and implant loss: A systematic review and meta-analysis.

OBJECTIVE: To evaluate the influence of supportive treatment (SPT) during a maintenance period after implant placement on implant survival rate (SR) and incidence of peri-implant diseases. MATERIAL AND METHODS: A systemic literature search for studies published up to June 2018 was conducted by two independent reviewers using Pubmed/MEDLINE, EMBASE, and Cochrane Central databases. Clinical controlled trials (CCT) involved in SPT protocol with more than 1-year follow-up were included. Quantitative meta-analyses were carried out to analyze the risk ratio (RR) of SR, the incidence of peri-implantitis, and peri-implant mucositis between SPT and non-SPT groups. Any potential confounding factors were investigated using meta-regression. RESULTS: Nine CCTs fulfilled the criteria. To evaluate the influence of SPT on SR, peri-implantitis, and peri-implant mucositis, six of nine, three of nine, and three of nine articles were included in further meta-analysis, respectively. SPT group significantly showed higher SR (RR: 1.10; p < 0.001), lower prevalence of peri-implantitis (RR: 0.25; p < 0.001) and peri-implant mucositis (RR: 0.57; p < 0.001) than the non-SPT group. Meta-regression of the selected studies failed to find an association between SR, peri-implantitis, and peri-implant mucositis and confounding factors: application of chemical agents and the frequency of SPT. CONCLUSION: SPT can potentially improve peri-implant health in terms of SR, peri-implantitis, and peri-implant mucositis. Additionally, the correlation in recall interval and adjunctive use of chemical agents during SPT to peri-implant diseases and implant loss could not be found.

Impact of timing on soft tissue augmentation during implant treatment: A systematic review and meta-analysis.

BACKGROUND: To achieve a predictable esthetic and functional outcome, soft tissue augmentation has become popular in implant treatment. OBJECTIVES: The aim of this systematic review and meta-analysis was to assess the influence of different timing for soft tissue augmentation during implant treatment on soft tissue conditions and its stability. MATERIAL AND METHODS: Electronic and manual searches for articles written in English up to September 2017 were performed by two independent reviewers. Human clinical studies with the purpose of evaluating outcomes (at least 3-month follow-up) of autogenous soft tissue graft for augmentation during implant treatment, either simultaneous or after implant placement (staged), were included. Cumulative changes of keratinized tissue width (KTW), soft tissue thickness (STT), and mid-buccal mucosal recession (MR) data were analyzed with a random-effects model to compare the postoperative outcomes. RESULTS: Twenty-nine human studies (eight randomized clinical trials, six cohort studies, and 15 case series) that met the inclusion criteria were included. For the overall data, the weighted mean STT gain (1 year after surgery) was 1.03 mm (95% CI: 0.78-1.29 mm), among which the simultaneous group was 1.12 mm (95% CI: 0.75-1.49 mm) and staged group (3-6 months after implant placement) was 0.95 mm (95% CI: 0.58-1.31 mm). There was no statistically significant difference in KTW and MR between 3 months and more than 3 months after surgery. CONCLUSIONS: This review revealed that the stability of soft tissue, in terms of KTW and mid-buccal MR, can be obtained 3 months after surgery. There is no difference between simultaneous and staged soft tissue augmentation during implant treatment, and both procedures significantly enhance KTW and STT.

Nonsurgical periodontal treatment and prosthetic rehabilitation of a renal transplant patient with gingival enlargement: a case report with 2-year follow-up.

BACKGROUND: Drug-induced gingival enlargement is a common condition which can be observed in patients taking immunosuppressive medications following organ transplant surgery. The disfiguring excessive tissue often hinders proper oral hygiene practices, therefore accompanied by periodontitis, tooth mobility, and even pathological tooth migration in extreme cases. This case report presents a conservative treatment protocol for a patient with the aforementioned conditions involving neither surgical nor orthodontic intervention. Few related studies have reported such a noninvasive protocol for managing these kinds of conditions. CASE PRESENTATION: A 51-year-old woman presented with bleeding gingiva, mobile teeth and complained of chewing difficulties. She had undergone renal transplant surgery 16 years prior to this dental visit and had been taking immunosuppressive drugs including cyclosporine ever since. After clinical and radiographic examinations, the patient was diagnosed with drug-induced gingival enlargement, pathological tooth migration, severe periodontitis, and missing teeth. Through careful and meticulous nonsurgical debridement, oral hygiene instruction, tooth extraction, and occlusal adjustment, the patient's periodontium was restored to a healthy state without surgical intervention. Moreover, the patient's chewing function was restored by means of removable partial dentures. Good adaptation of prostheses and satisfaction with overall treatment outcomes were reported. CONCLUSIONS: Through proper diagnosis, treatment, and with good patient cooperation, complex systemic and dental problems can be managed conservatively without invasive surgeries to attain a stable periodontium and eventually, occlusal function could be restored.

Evaluation of the Mandibular Lingual Canal and Anterior Loop Length to Minimize Complications Associated With Anterior Mandibular Surgeries: A Cone-Beam Computed Tomography Study.

PURPOSE: This retrospective study evaluated the localization, incidence, and dimensions of the mandibular lingual canal and the anterior loop in the Taiwanese population using the simulation and visual interpretation of cone-beam computed tomography to minimize complications during symphysis block surgical procedures. MATERIALS AND METHODS: The sample population consisted of 215 patients (105 men and 110 women; mean age, 57 yr). The median lingual canal, symphysis bone thickness, and anterior loop length were defined and calculated using cone-beam computed tomography and 3-dimensional reconstructed images. The correlation of all data for men and women was assessed and analyzed statistically using unpaired t tests. RESULTS: All patients exhibited at least 1 median lingual canal in the symphysis, and the diameter of the main branch ranged from 0.21 to 1.48 mm (mean, 0.85 mm), with relevant differences between genders (longer in men than in women). A harvesting depth of 4 mm for the distance from the buccal bone to the terminal end of the median lingual canal resulted in a risk of neurovascular injury (13.0%); this risk was notably higher in women (19.1%) than in men (6.7%). The right and left anterior loop lengths ranged from 0 to 5.46 mm (mean, 2.60 mm) and from 0 to 5.57 mm (mean, 2.61 mm), respectively, with no relevant differences between genders or sides. CONCLUSIONS: The results suggest that routine cone-beam computed tomographic examinations before surgical interventions in the symphysis region are necessary because of the numerous complicated anatomic variations.

Preparation and Evaluation of Aminomalononitrile-Coated Ca-Sr Metal-Organic Frameworks as Drug Delivery Carriers for Antibacterial Applications.

After orthopedic surgery, antibiotics are usually employed to reduce the risk of infection. If it is possible to enhance antimicrobial functionality and incorporate antimicrobial agents into the bone-filling matrix, not only it can promote bone tissue regeneration, but it can also enable localized administration of medication to elevate antibacterial efficacy. Meanwhile, previous studies have shown that calcium and strontium can support the growth of osteoblastic cells and diminish bone resorption or deterioration. In the past few years, metal-organic frameworks (MOFs) have been widely used as drug carriers owing to their characteristic advantages. In this study, a MOF was prepared in an aqueous solution by a simple coprecipitation method with the organic ligand 1,3,5-tricarboxylic benzene (H3BTC) as a linker to form Ca-Sr-MOF. Furthermore, the Ca-Sr-MOF was coated with aminomalononitrile (AMN), which adhered through the electrostatic interactions between H3BTC and AMN. With this MOF (Ca-Sr-AMN-MOF), AMN polymerization reactions can occur in aqueous environments, and a polymer layer was observed on the MOF surface with moderate hydrophilicity. The prepared Ca-Sr-MOF and Ca-Sr-AMN-MOF were characterized by Fourier transform infrared spectroscopy, powder X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, and UV-visible spectroscopy. Finally, tetracycline (TC) was selected as the model drug to measure the drug loading efficiency, release profile, and antibiotic activity. The percent cumulative drug release of TC from Ca-Sr-MOF and Ca-Sr-AMN-MOF was 55.15 and 9.1%, respectively. The antibacterial effectiveness of TC-loaded MOF against Gram-negative Escherichia coli bacteria was evaluated, revealing the remarkable antimicrobial performance of these substances.

Assessment of a Novel Alveolar Ridge Preservation Concept in Dehiscence Sockets: A Pilot Study.

In this prospective pilot study on ridge preservation (RP), a collagen sponge was placed to fill the bottom half of the socket, followed by a sequence of bone graft, collagen membrane, and a sponge placed on top. Twelve patients with 13 hopeless posterior teeth were included. Changes in bone dimension (including variations of horizontal ridge width [HRW] and bone height [BH]) between the time immediately postextraction (T0) and 6 months later (T6M) were evaluated through CBCT. The soft tissue was assessed using a wound healing index (WHI) at 2 weeks (T2W), 2 months (T2M), and 6 months (T6M) postsurgery. Measured at three parallel levels (1, 3, and 5 mm apical to the crest of the palatal plate), the mean HRW changes (T0 to T6M) ranged from 0.47 to 1.05 mm. Statistically significant negative correlations were observed between WHI (T6M) and midcrestal BH change. This proposed RP technique showed favorable outcomes regarding HRW and BH, even in periodontally compromised dehiscence sockets.

The Impact of Implantoplasty in Regenerated and Nonregenerated Treatment Modalities in Peri-implantitis: A Systematic Review and Meta-analysis.

PURPOSE: To investigate the impact of implantoplasty (IP) with or without regenerative procedures on treatment outcomes of peri-implantitis. MATERIALS AND METHODS: Electronic and manual literature searches were conducted for clinical trials published up to October 2020 that evaluated clinical outcomes (at least 6-month follow-up) after peri-implantitis treatment involving IP. The implant survival rate and clinical parameters (eg, probing depth [PD], bleeding on probing [BOP], marginal bone loss [MBL], clinical attachment level [CAL], and mucosal recession [REC]) at baseline and follow-ups were extracted from original articles for qualitative analyses. Risk ratio and weighted mean difference with 95% CI were calculated using a random-effects model. RESULTS: Out of 322 studies, 17 (9 randomized controlled trials, 4 controlled clinical trials, and 4 case series) were included in the present study. The regeneration group presented a 97% (95% CI: 0.95 to 1.00) implant survival rate, and the nonregeneration group showed a 94% (95% CI: 0.90 to 0.98) survival rate. Both groups revealed similar outcomes in PD and BOP reductions and soft tissue REC. However, the regeneration group had more favorable results in MBL. CONCLUSION: Data from this study suggested that applying implantoplasty during a regeneration or nonregeneration surgical approach resulted in a high implant survival rate and peri-implantitis resolution. Although no differences were found in the majority of clinical parameters in both groups, the regenerative approach resulted in more radiographic bone fill than the nonregenerative treatment.

Influence of the Components and Orientation of Hydroxyapatite Fibrous Substrates on Osteoblast Behavior.

Synthetic hydroxyapatite has good biocompatibility, bioactivity and osteoconductive ability because its chemical properties and biological properties are similar to those of bioapatite in bone tissue. Strontium-substituted hydroxyapatite has better degradability than hydroxyapatite and can both promote osteogenesis and inhibit adipogenesis in mesenchymal stem cells. Hence, hydroxyapatite and strontium-substituted hydroxyapatite are widely used as bone graft materials, cell carriers and drug/gene delivery carriers. In addition, osteoblasts cultured on aligned nanofibrous substrates had higher expression of osteogenesis-related genes than did those cultured on random nanofibrous substrates. However, to date, no study has explored the effects of the components and orientation of hydroxyapatite nanofibrous substrates on osteoblastic behavior. In this study, a random hydroxyapatite nanofibrous substrate (R-HANF), a random strontium-substituted hydroxyapatite nanofibrous substrate (R-SrHANF), an aligned hydroxyapatite nanofibrous substrate (A-HANF) and an aligned strontium-substituted hydroxyapatite nanofibrous substrate (A-SrHANF) were successfully fabricated by using the electrospinning technique. The effect of fiber composition on osteoblast-like MG63 cells was assessed by evaluating cell morphology, cell proliferation and osteogenesis-related gene expression. The results showed that MG63 cells cultured on A-SrHANF had higher osteogenesis-related gene expression than those cultured on A-HANF. Additionally, MG63 cells were cultured on R-SrHANF and A-SrHANF to evaluate the effects of fiber orientation on cell behavior. On A-SrHANF, the cells aligned along the direction of the nanofibers, with typical bipolar morphologies, and exhibited higher osteogenesis-related gene expression than cells on R-SrHANF. Hence, the components and orientation of hydroxyapatite nanofibrous substrates are critical parameters affecting the osteogenesis process.

Grafted bone remodeling following transcrestal sinus floor elevation: A cone-beam computed tomography study.

BACKGROUND: Transcrestal sinus floor elevation is a reliable procedure when additional bone height is needed for maxillary implant placement. However, the grafted bone undergoes remodeling and the dimensional stability of grafted bone height may be affected by several clinical factors, including graft material, sinus anatomy and the morphology of grafted space. METHODS: This retrospective study examined patients who had undergone transcrestal sinus floor elevation with synthetic biphasic calcium phosphate and single implant placement. The reduction of sinus graft height (GHR) after 6-8 months healing period was measured with cone-beam computed tomography (CBCT) images. Correlating factors, including vertical amount of implant protrusion (IP), sinus width, and the morphology of grafted space were analyzed by Spearman's correlation test. RESULTS: A total of 25 implant sites were analyzed. The mean GHR was 0.57 ± 0.49 mm, which was positively correlated with IP, vertical elevation height (VEH), and the ratio of vertical to horizontal elevation of the grafted space. However, GHR was not correlated with sinus width and mesial-distal or buccal-palatal width of the grafted space. CONCLUSIONS: Synthetic biphasic calcium phosphate used in transcrestal sinus floor elevation underwent shrinkages and graft remodeling. Grafted height reduction was associated with IP, VEH, and the ratio of vertical to horizontal elevation of the grafted space.

The Effect of Strontium-Substituted Hydroxyapatite Nanofibrous Matrix on Osteoblast Proliferation and Differentiation.

Natural bone tissue consists primarily of bioapatite and collagen. Synthetic hydroxyapatite (HA) possesses good biocompatibility, bioactivity, and osteoconductivity due to its chemical and biological similarity to bioapatite. Hence, HA has been widely used as a bone graft, cell carrier and drug/gene delivery carrier. Moreover, strontium-substituted hydroxyapatite (SrHA) can enhance osteogenic differentiation and inhibit adipogenic differentiation of mesenchymal stem cells. Hence, SrHA has the potential to be used as a bone graft for bone regeneration. It is widely accepted that cell adhesion and most cellular activities are sensitive to the topography and molecular composition of the matrix. Electrospun polymer or polymer-bioceramic composite nanofibers have been demonstrated to enhance osteoblast differentiation. However, to date, no studies have investigated the effect of nanofibrous bioceramic matrices on osteoblasts. In this study, hydroxyapatite nanofiber (HANF) and strontium-substituted hydroxyapatite nanofiber (SrHANF) matrices were fabricated by electrospinning. The effect of the HANF components on MG63 osteoblast-like cells was evaluated by cell morphology, proliferation, alkaline phosphatase activity (ALP) and gene expression levels of RUNX2, COLI, OCN and BSP. The results showed that MG63 osteoblast-like cells exhibited higher ALP and gene expression levels of RUNX2, COLI, BSP and OCN on the SrHANF matrix than the HANF matrix. Hence, SrHANFs could enhance the differentiation of MG63 osteoblast-like cells.

Gelatin Hydrogels Reinforced by Absorbable Nanoparticles and Fibrils Cured In Situ by Visible Light for Tissue Adhesive Applications.

Most gelatin hydrogels used in regenerative medicine applications today are fabricated by photocrosslinking due to the convenience and speed of this method. However, in most cases photoinitiators are used, which require UV light, which, in turn, can cause cell and tissue damage, or using functionalized gelatin. Recently, ruthenium (II) tris-bipyridyl chloride has been studied as an initiator that can induce dityrosine bond formation using visible light. In addition, continuous fibrils and small particles are often used to reinforce composite materials. Therefore, this study investigated the visible-light-induced photocrosslinking of native gelatin molecules via dityrosine bonds formation as well as gel reinforcement by collagen fibrils and mesoporous bioactive glass (MBG) particles. The results show that collagen and MBG exerted a synergistic effect on maintaining gel integrity with a dental LED curing light when the irradiation time was shortened to 30 s. Without the two reinforcing components, the gel could not form a geometric shape stable gel even when the exposure time was 120 s. The shear strength increased by 62% with the collagen and MBG compared with the blank control. Furthermore, our results demonstrate that the addition of collagen and MBG enhanced gel stability in an artificial saliva solution. These results demonstrate the considerable advantages of using tyrosine-containing biomolecules, and using a dental LED curing light for the crosslinking of hydrogels in terms of their suitability and feasibility for use as bioadhesives in confined clinical working space, such as the oral cavity, and in application as in situ-crosslinked injectable hydrogels.

Is History of Periodontal Disease Still a Negative Risk Indicator for Peri-implant Health Under Supportive Post-implant Treatment Coverage? A Systematic Review and Meta-analysis.

PURPOSE: Among all previous studies, history of periodontitis (HP) has been regarded as a negative indicator for peri-implant health. However, the role of HP under regular supportive post-implant treatment (SPT) has not yet been evaluated. The aim of this review was to evaluate whether HP remains a negative indicator even under regular SPT in terms of clinical outcomes. MATERIALS AND METHODS: Two independent reviewers conducted electronic and manual searches of the literature in English from January 2003 to May 2018. Human clinical studies including both patients with and without HP under SPT with more than 1-year follow-up and complete information about peri-implant conditions were included. Risk ratio (RR) for implant survival rate, weighted mean difference (WMD) for radiologic marginal bone loss, pocket depth, bleeding on probing, and Plaque Index were analyzed to compare the outcomes in patients with and without HP. RESULTS: Thirteen human studies fulfilling the inclusion criteria were selected. Based on the results of meta-analyses, in implants with a rough surface, even under the regular SPT, the HP group showed a lower implant survival rate (RR: 0.96, 95% confidence interval [CI]: 0.94 to 0.98, P < .001) and more radiologic marginal bone loss (WMD: 0.34 mm, 95% CI: 0.20 to 0.48, P < .001), pocket depth (WMD: 0.47 mm, 95% CI: 0.19 to 0.74, P < .001), and bleeding on probing (WMD: 0.08 mm, 95% CI: 0.04 to 0.11, P < .001) than the non-HP group. In implants with a machined surface, HP also showed a negative effect on bone loss (WMD: 0.88 mm, 95% CI: 0.65 to 1.11, P < .001). However, in implants with a machined surface, no statistical significance in survival rate was found between HP and non-HP patients (RR: 0.98, 95% CI: 0.92 to 1.04, P = .895). CONCLUSION: Within the limitations of this review, HP remains a negative indicator for implant survival even under regular supportive post-implant treatment coverage in rough-surfaced implants.

Comparison of 4 sinus augmentation techniques for implant placement with residual alveolar bone height ≤3 mm.

This study compared implant outcomes following maxillary sinus floor augmentation (MSFA) in edentulous patients with a residual alveolar bone height ≤3 mm. Four techniques were evaluated: 1-stage bone-added osteotome sinus floor elevation procedure (BAOSFE) with simultaneous implant placement; 2-stage BAOSFE with delayed implant placement; 1-stage lateral window sinus floor elevation with simultaneous implant placement; and 2-stage lateral window sinus floor elevation with delayed implant placement. Patients were followed for 18 to 72 months (mean: 52.5 months) after prosthesis placement. Data were analyzed with cone-beam computed tomography. A total of 96 implants from 71 patients were analyzed; pretreatment, there were no significant differences between patients. Total implant survival was 98.9%. The mean residual bone height was significantly higher in the 1-stage BAOSFE group than the other groups (P < .01); 1 implant in this group failed at 3 months. There was no significant difference in total bone height gain between groups. However, the bone height gain of 1st sinus lifting with 2-stage BAOSFE was significantly lower than the 2-stage lateral window procedure (P < .01). There was no prosthesis failure. The favorable implant outcomes suggest these 1-stage and 2-stage MSFA procedures should be considered as alternative treatment options for patients with extremely atrophic posterior maxilla.

Effect of Platelet-Rich Fibrin on Ridge Preservation in Perspective of Bone Healing: A Systematic Review and Meta-analysis.

PURPOSE: Among all platelet concentrates, platelet-rich fibrin has been shown to possess fibrin, leukocytes, and a variety of growth factors that could promote wound healing. The purpose of this study was to compare the bone healing in natural healing sockets (control group) versus that in sockets under ridge preservation with platelet-rich fibrin alone (test group). MATERIALS AND METHODS: Searches were conducted via electronic and manual approaches for randomized controlled trials and controlled clinical trials published up to May 2018 that evaluated alveolar ridge outcomes (at least 1-month follow-up) in both natural healing sites and sites with platelet-rich fibrin placement alone for ridge preservation. Changes of ridge height and width, osteoblastic activity, and the number of sites were extracted from original articles for meta-analyses. Weighted mean difference and 95% confidence interval were calculated using a random-effects model. RESULTS: Eight human studies (six randomized controlled trials and two controlled clinical trials) that fulfilled the inclusion criteria were included in the study. Data obtained in the study showed a favorable outcome in platelet-rich fibrin for socket preservation, although the difference was not statistically significant when compared to the natural healing group with regard to alveolar bone height change (weighted mean difference: -0.28 mm, 95% confidence interval: -0.55 to 0.00, P = .051), alveolar bone width change (weighted mean difference: -1.73 mm, 95% confidence interval: -3.58 to 0.12, P = .067), or osteoblastic activity (weighted mean difference: -0.01 [unit], 95% confidence interval: -0.50 to 0.49, P = .982). CONCLUSION: This study revealed that platelet-rich fibrin alone in ridge preservation does not provide significant additional benefit when compared to natural healing sockets with regard to bone volume, bone density, and osteoblastic activity.

Cone-beam computed tomography assessment of Schneiderian membranes: Non-infected and infected membranes, and membrane resolution following tooth extraction: A retrospective clinical trial.

BACKGROUND: Cone-beam computed tomography (CBCT) presurgical assessment on the maxillary sinus can reduce the possibility of Schneiderian membrane perforation. This study examined Schneiderian membrane thickness (SMT) and its relationship with neighboring hard tissues for patients with and without membrane thickening. For patients with sinus infections, we evaluated dimensional changes of the SMT post-extraction relative to pre-extraction SMT and residual bone height (RBH). METHODS: CBCT images from 93 patients needing single-tooth implant reconstruction without (n = 83) and with (n = 14) odontogenic infected maxillary sinuses were assessed. SMT, RBH, and lateral wall thickness (LWT) were measured. Causes of extraction, RBH in the infection site, and retrospective post-extraction record of SMT were recorded for the thickened SMT group. RESULTS: Mean SMT for normal SMT group was 1.13 ± 0.43 mm, RBH was 6.26 ± 2.38 mm; upper and lower LWT was 1.85 ± 0.95 mm, and 3.07 ± 2.26 mm, respectively. RBH and LWT had no significant relationships with SMT. For thickened SMT group, mean values for SMT and RBH prior to extraction were 4.53 ± 2.46 mm and 1.97 ± 1.43 mm, respectively. Pre-extraction SMT had a moderately negative correlation with pre-extraction RBH. SMT resolution in thickened SMT group was observed by 2.80 ± 1.37 months post-extraction; post-extraction SMT was not significantly different from normal SMT group (p = .187). CONCLUSIONS: Within the limitation of the sample size, thickened SMT induced by odontogenic infection subsides about 3 months following tooth extraction, and further sinus lifting implant surgery may be considered.

Facial Fenestration and Dehiscence Defects Associated With Immediate Implant Placement Without Flap Elevation in Anterior Maxillary Ridge: A Preliminary Cone Beam Computed Tomography Study.

PURPOSE: To examine cone beam computed tomography (CBCT) anatomical findings, such as the concavity of the ridge and angulation of the tooth and alveolar ridge, either facial or palatal, in order to assess the potential clinical risks of performing flapless implant surgery. MATERIALS AND METHODS: CBCT images that met the inclusion criteria were examined. All images in maxillary anterior areas (canine to canine), facial bone thickness at 3 and 5 mm from the cementoenamel junction (CEJ), angulation of the tooth and alveolar ridge (Angle T: the angulation between the long axis of the tooth and the palatal plane; Angle D: the angulation between the long axis of the tooth and the midline of the ridge), the deepest point of facial concavity, the distance from the deepest point of facial concavity to the apex of the tooth and alveolar bone crest, nasopalatine canal, dehiscence, and fenestrations were measured and statistically analyzed. RESULTS: In total, 21 patients (12 women and 9 men) with a mean age of 55.9 years who met the inclusion criteria were included in the analysis. Data from 21 patients, 6 image sections per patient (total of 126 CBCT images) were analyzed. The mean value of facial bone thickness was 0.99 mm and 0.60 mm at 3 and 5 mm from CEJ, respectively. The distance from the deepest point of facial concavity to the apex of the tooth and alveolar bone crest was 2.79 and 11.29 mm, respectively. In canine areas, the mean values of facial bone thickness were larger at 3 mm but thinner at 5 mm. Also, canines were found to have a larger Angle D and a higher incidence of fenestration and dehiscence. CONCLUSION: Based on the findings, fenestration and a larger Angle D were associated with thinner facial bone thickness at 5 mm, and the tooth types also had an impact. Hence, for immediate implant surgery without flap elevation, besides anatomical structures, both angulation of the tooth and the alveolar ridge also need to be assessed.

Strontium ranelate treatment in a postmenopausal woman with osteonecrosis of the jaw after long-term oral bisphosphonate administration: a case report.

Bisphosphonates (BPs) suppress bone resorption and increase bone strength, thus reducing the risk of fracture. Oral BPs are widely used for the prevention and treatment of osteoporosis and osteopenia. Here, we describe the case of a postmenopausal woman who took oral alendronate for >3 years for osteoporosis. The patient presented at the clinic with sharp jaw pain and swelling on the left mandible 4 months after extraction of the third molar. Clinical examinations identified an inflamed mucosal opening with pus over an area of necrotic bone. Initial images of cone beam computed tomography revealed a sequestrum at the extracted socket. The condition did not improve after 1 week of antibiotic treatment; therefore, the alendronate treatment was terminated and the patient was prescribed strontium ranelate instead. The patient gradually recovered and, at the 2-year follow-up, the site of BP-related osteonecrosis of the jaw healed completely as determined by both clinical and cone beam computed tomography measures. The bone mineral densities in the femoral neck and lumbar spine improved after 1 year, and were maintained at the 3-year follow-up. The serum C-terminal cross-linking telopeptide values also gradually increased from the initial 130 pg/mL to 320 pg/mL at the 3-year follow-up. Taken together, this case supports the use of strontium ranelate as an alternative treatment for postmenopausal women who receive long-term oral BP treatments and are at risk for serious complications of BP-related osteonecrosis of the jaw.

Bone graft necrosis of facial translocation: comparison of 3 different techniques.

OBJECTIVE: To compare the viability of translocated facial bone grafts among 3 different techniques of facial translocation: free bone graft (FBG), attached bone graft (ABG), and modified facial translocation (MFT). STUDY DESIGN: A total of 107 patients were divided into 3 groups: FBG group without reconstruction (N = 33), ABG group (N = 14), and FBG group with reconstruction using a flap (FBG[R+] and MFT) (N = 60). Data evaluated included the respective incidence of bone graft necrosis (BGN) and the impact of radiotherapy. RESULTS: The incidence of BGN significantly varied among the three different groups (P = 0.00003): FBG[R-] (11/33[33.3%]), ABG (1/14[7.1%]) and FBG[R+] and MFT (1/60[1.67%]). Soft tissue reconstruction significantly decreased the incidence of BGN (P = 0.00003), even in patients with radiation therapy (P = 0.00001). CONCLUSIONS: MFT significantly increases the viability of translocated facial bone grafts, which provides a good surgical approach to the anterior skull base.

The anatomical basis for mandibulotomy: midline versus paramidline.

OBJECTIVE: To provide an anatomical basis for mandibulotomy. STUDY DESIGN: Prospective. METHODS: The angles between the long axis of the two mandibular central incisors and between the lateral incisor and canine and the corresponding root length were measured in panoramic films of 50 Taiwanese patients who had oral or oropharyngeal carcinomas. RESULTS: The angle and horizontal distance between the mandibular lateral incisor and canine were significantly wider than between the two central incisors. The root length of the canine measured 16 mm on average. CONCLUSIONS: Paramidline mandibulotomy, which cuts through a wider space between the lateral incisor and canine, preserves dentition and the genioglossus and geniohyoid muscles. It appears to be a more preferable approach than midline mandibulotomy.

The use of the facial translocation technique in the management of tumors of the paranasal sinuses and skull base.

OBJECTIVE: We sought to assess the efficacy of facial translocation in the management of tumors of the skull base and paranasal sinuses. STUDY DESIGN AND SETTING: From July 1993 to December 1999, 75 patients, aged 3 to 102 years old, underwent facial translocation. Thirty-three (44%) patients also underwent a combined neurosurgical procedure. Nineteen (25%) had previous surgery. These patients were followed up to 6 years. RESULTS: There were 21 benign and 54 malignant tumors. There were no perioperative deaths. The morbidity rate was 31%. Of the 54 patients with malignant tumors, the actuarial 3-year survival rate was 59%, whereas the local control rate was 54%. CONCLUSION: The facial translocation technique offers favorable exposure of the critical zones of the anterior and middle cranial base, thus facilitating extensive resection and reconstruction. SIGNIFICANCE: This study demonstrates that facial translocation is one of the best surgical approaches to the skull base.