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OBJECTIVES The aim of this systematic review was to investigate the association between the intake of systemic medications that may affect bone metabolism and their subsequent impact on implant failures. MATERIAL AND METHODS Electronic and manual literature searches were conducted. Implant failure (IF) was the primary outcome, while biological/mechanical and the causes/timing associated with IF were set as secondary outcomes. Meta-analyses for the binary outcome IF and odds ratio were performed to investigate the association with medications. RESULTS A final selection of 17 articles was screened for qualitative assessment. As such, five studies focused on evaluating the association of implant failure and non-steroidal anti-inflammatory drugs (NSAIDs), two on selective serotonin reuptake inhibitors (SSRIs), two on proton pump inhibitors (PPIs), seven on bisphosphonates (BPs), and one on anti-hypertensives (AHTNs). For PPIs, the fixed effect model estimated a difference of IF rates of 4.3%, indicating significantly higher IF rates in the test compared to the control group (p

OBJECTIVES To investigate the impact of progressive bone loss in an experimental peri-implantitis model in the dog upon the implant stability quotient (ISQ) measured in the course of induced and spontaneous conditions of disease, and to evaluate the association between the clinical parameters and ISQ. MATERIALS AND METHODS Seventy-two implants were placed in 12 Beagle dogs. Of these, 36 implants in six dogs were assessed during ligature-induced peri-implantitis (three timepoints) and at one timepoint following a period of spontaneous progression. The ISQ was recorded using resonance frequency analysis (RFA). Furthermore, the clinical peri-implant parameters were registered at four sites per implant at each timepoint. Marginal bone loss (MBL) was determined using computed tomography at four sites per implant and bone-to-implant contact (BIC) was assessed from histological samples. A linear regression model was estimated by generalized estimation equations (GEEs) in order to study the MBL-ISQ values at each measurement timepoint. Pearson's correlation test was applied. RESULTS None of the implants failed during the study period. At implant level, a strong negative correlation was found for all timepoints between ISQ and MBL (r = -0.58; p

OBJECTIVES To evaluate the effect of a resorbable collagen membrane and autogenous bone chips combined with deproteinized bovine bone mineral (DBBM) on the healing of buccal dehiscence-type defects. MATERIAL AND METHODS The second incisors and the first premolars were extracted in the maxilla of eight mongrels. Reduced diameter, bone-level implants were placed 5 weeks later. Standardized buccal dehiscence-type defects were created and grafted at implant surgery. According to an allocation algorithm, the graft composition of each of the four maxillary sites was DBBM + membrane (group D + M), autogenous bone chips + DBBM + membrane (group A + D + M), DBBM alone (group D) or autogenous bone chips + DBBM (group A + D). Four animals were sacrificed after 3 weeks of healing and four animals after 12 weeks. Histological and histomorphometric analyses were performed on oro-facial sections. RESULTS The pattern of bone formation and resorption within the grafted area showed high variability among the same group and healing time. The histomorphometric analysis of the 3-week specimens showed a positive effect of autogenous bone chips on both implant osseointegration and bone formation into the grafted region (P

Background The use of autogenous block grafts harvested from intraoral donor sites has proven to be effective for the reconstruction of horizontal bone defects. Purpose The objective of this study was to analyze implant success and the rate of block graft resorption 10 years after ridge augmentation to elucidate contributing factors influencing graft maintenance. Materials and Methods A staged horizontal block graft augmentation was performed in 52 implant sites exhibiting severe horizontal bone atrophy using autogenous block grafts protected by DBBM and collagen membranes. The crest width was assessed intraoperatively at surgery and at re-entry after 6 months. At the 10 year reexamination clinical and radiographic parameters were assessed using cone beam computed tomography. Results The 10-year implant success rate amounted to 98.1%, with minimal peri-implant bone loss (−0.17 mm for the maxilla, −0.09 mm for the mandible). The surface resorption rate after 10 years was 7.7% (0.38 mm). Grafts originating from the chin demonstrated significantly better graft maintenance at 10 years compared to retromolar grafts. Recipient site and age had no significant impact on graft resorption, whereas females showed more bone loss at the 10-year examination. Conclusions Lateral ridge augmentation using autogenous block grafts and guided bone regeneration demonstrated a favorable success rate of 98.1% with minimal block graft resorption of 7.7% after 10 years. Modulating factors were origin of the graft and gender.

OBJECTIVES The aim of the present observational medical device performance study was to test whether implants with an intra-operatively conditioned hydrophilic surface can be safely reconstructed when applying an early loading protocol after 21 days in partially edentulous posterior mandibles. MATERIAL AND METHODS Partially edentulous patients with missing teeth in the posterior mandible were recruited. Immediately after implant placement, the implant position was indexed using a pickup impression technique. ISQ values were measured after 21 days of healing. When ISQ values were ≥70, the implants were directly restored with provisional reconstructions in occlusal contact allowing an early loading protocol. ISQ values were repeated again at 1, 3, and 6 months postloading. Clinical parameters (mPLI, mSBI, PPD, DIM, and CAL) were assessed. Standardized periapical radiographs were obtained after surgery, at implant loading and 3 and 6 months later. Changes over time were analyzed for statistical significance using the nonparametric method by Brunner & Langer (SAS Proc Mixed). RESULTS Fifteen partially edentulous patients with healed sites in the posterior mandible received 20 implants. All implants healed uneventfully. At 21 days, all implants achieved an ISQ value of ≥70 (mean of 3 measurements) and were reconstructed at this time point with provisionals. ISQ values showed a gradual increase from baseline to 3 and 6 months postloading. The assessment of clinical parameters revealed stable tissue integration. The evaluation of the radiographs showed that 3 and 6 months after loading the median mesial and distal marginal bone levels had stabilized at the border between the rough surface and the 1-mm machined implant collar. CONCLUSION Functional occlusal loading of implants with a hydrophilic, moderately rough endosseal surface 3 weeks after placement appears to be a safe and predictable treatment option in healed sites in the posterior mandible without need of bone augmentation procedures.

BACKGROUND Current strategies to reduce medical device-associated infections propose zirconia as a potential implant material which may limit bacterial adhesion. Because multinucleated giant cells (MNGCs) have been detected on these implant surfaces, concerns have been raised regarding tissue integration. PURPOSE The present study examined the presence of MNGCs and their subsequent effect upon tissue integration. Surface-modified implants made of yttria-stabilized (TZP) and alumina-toughened zirconia (ATZ) were compared with commercially pure titanium (Ti). MATERIALS AND METHODS Seven miniature pigs received three implants on either side of the maxilla. After healing periods of 4 and 8 weeks, the tissue response at the implant surfaces was characterized according to three specific parameters: bone-to-implant contact (BIC), MNGC-to-implant contact (MIC), and the peri-implant bone density (BD). RESULTS Despite being present on all tested implant surfaces, MNGCs were not associated with an inflammatory cell infiltrate or with fibrous encapsulation. MNGCs were less numerous on the Ti implants (range: 3.9-5.2%) compared with the ceramic implants (range: 17.6-30.3%, p

Implant placement in post-extraction sites of single teeth in the esthetic zone has been a topic of great interest in the field of implant dentistry since 1990. Triggered by the development of guided bone regeneration, the concept of immediate implant placement became quite popular in the 1990s. In the past 12 years, however, the dental community has begun to focus increasingly on the esthetic outcomes of post-extraction implant placement and several studies indicated a significant risk for the development of mucosal recessions with immediate implants. Parallel with this, significant progress has been made in the understanding of tissue biology in terms of hard and soft tissue alterations post extraction, based on preclinical, clinical and radiological studies. This knowledge has helped better to understand the etiology of these esthetic complications with immediate implant placement. The present review first analyzes the various phases of the development of therapeutic strategies over the years for post-extraction implant placement in single tooth sites in the esthetic zone. It presents the current knowledge concerning the terminology with immediate, early and late implant placement, the risk factors for the development of esthetic complications, and the selection criteria for the various treatment options. In the second part, clinical recommendations are given, since a clinician active in this field of implant therapy can use all treatment options depending on the preoperative analysis including a 3D cone beam computed tomography. The selection criteria for all four treatment options are presented and documented with typical case reports to illustrate the current treatment approaches applied in daily practice.

Facial peri-implant mucosal recessions represent an increasing complication in implant dentistry and may negatively affect the esthetic outcome and patient satisfaction. The aim of the present paper is to provide a review on the potential causes of facial peri-implant mucosal recessions and to provide a rationale for treatment along with possible treatment options. The available data indicate that soft tissue augmentation around dental implants is possible, but at present there is no evidence demonstrating that the augmented soft tissues are able to influence the peri-implant bone levels (e.g. to limit peri-implant bone loss). Therefore, the rationale to cover or correct peri-implant mucosal recessions are (i) to optimize the possibility for performing an adequate level of oral hygiene, and (ii) to improve esthetics. At present, there is very limited evidence supporting any specific treatment modality for covering peri-implant soft tissue recessions. The limited available data indicate that only shallow peri-implant mucosal recessions (e.g. up to 2 mm) may be treated successfully by means of a coronally advanced flap and subepithelial connective tissue graft or with guided bone regeneration, while no data are available supporting the possibility of covering deep and large peri-implant mucosal recessions.

Bone healing around dental implants follows the pattern and sequence of intramembraneous osteogenesis with formation of woven bone first of all followed later by formation of parallel-fibered and lamellar bone. Bone apposition onto the implant surface starts earlier in trabecular bone than in compact bone. While the first new bone may be found on the implant surface around 1 week after installation, bone remodeling starts at between 6 and 12 weeks and continues throughout life. Bone remodeling also involves the bone-implant interface, thus transiently exposing portions of the implant surface. Surface modifications creating micro-rough implant surfaces accelerate the osseointegration process of titanium implants, as demonstrated in numerous animal experiments. Sandblasting followed by acid-etching may currently be regarded as the gold standard technique to create micro-rough surfaces. Chemical surface modifications, resulting in higher hydrophilicity, further increase the speed of osseointegration of titanium and titanium-zirconium implants in both animals and humans. Surface modifications of zirconia and alumina-toughened zirconia implants also have an influence on the speed of osseointegration, and some implant types reach high bone-to-implant contact values in animals. Although often discussed independently of each other, surface characteristics, such as topography and chemistry, are virtually inseparable. Contemporary, well-documented implant systems with micro-rough implant surfaces, placed by properly trained and experienced clinicians, demonstrate high long-term survival rates. Nevertheless, implant failures do occur. A low percentage of implants are diagnosed with peri-implantitis after 10 years in function. In addition, a low number of implants seem to be lost for primarily reasons other than biofilm-induced infection. Patient factors, such as medications interfering with the immune system and bone cells, may be an element contributing to continuous bone loss and should therefore be monitored and studied in greater detail.

BACKGROUND Long-term studies of ≥10 years are important milestones to get a better understanding of potential factors causing implant failures or complications. PURPOSE The present study investigated the long-term outcomes of titanium dental implants with a rough, microporous surface (titanium plasma sprayed [TPS]) and the associated biologic and technical complications in partially edentulous patients with fixed dental prostheses over a 20-year follow-up period. MATERIALS AND METHODS Sixty-seven patients, who received 95 implants in the 1980s, were examined with well-established clinical and radiographic parameters. Based on these findings, each implant was classified as either successful, surviving, or failed. RESULTS Ten implants in nine patients were lost during the observation period, resulting in an implant survival rate of 89.5%. Radiographically, 92% of the implants exhibited crestal bone loss below 1 mm between the 1- and 20-year follow-up examinations. Only 8% yielded peri-implant bone loss of >1 mm and none exhibited severe bone loss of more than 1.8 mm. During the observation period, 19 implants (20%) experienced a biologic complication with suppuration. Of these 19 implants, 13 implants (13.7%) had been treated and were successfully maintained over the 20-year follow-up period. Therefore, the 20-year implant success rate was 75.8 or 89.5% depending on the different success criteria. Technical complications were observed in 32%. CONCLUSION The present study is the first to report satisfactory success rates after 20 years of function of dental implants with a TPS surface in partially edentulous patients.

Thirty-four patients with 45 avulsed and replanted permanent teeth were followed for 1 year. All teeth were soaked in tetracycline before replantation. In addition, enamel matrix derivative was used in teeth with dry storage times exceeding 30 min. Splinting was carried out with a non-rigid titanium splint and was limited to 7-10 days. Within that period, root canal treatment was begun in all teeth with a closed apex, whereas teeth with an open apex and ideal post-traumatic storage were not instrumented. All patients were given tetracycline systematically for 10 days. The survival rate of replanted avulsed permanent teeth was 95.6% at the 1-year follow-up. In 82.2%, root canal treatment was performed. Pulp survival was never observed, but three teeth had pulp canal obliteration. Normal periodontal healing was observed in 57.7% of teeth; 42.3% of teeth showed external root resorption (28.9% replacement resorption, 6.7% infection-related resorption, 6.7% surface resorption). The occurrence of replacement resorption correlated with the period of extraoral dry storage. Compared with other clinical studies on avulsed and replanted teeth, the present study reports a higher percentage of periodontal healing. The favorable treatment outcome may be associated with a strict protocol to enforce endodontic treatment, the use of topical and systemic tetracycline, and the relatively high number of ideally stored teeth following avulsion. In contrast, the present study has a follow-up period limited to 1 year.

Objective To analyse the occurrence and resolution of neurosensory disturbances following bone harvesting from the symphysis. Material and methods In 30 patients, skin sensitivity of the chin/lower lip area and pulp sensitivity of all mandibular anterior teeth were assessed preoperatively, at the time of suture removal, at 6 and 12 months postoperatively. In addition, bone defect dimensions of the donor site were measured intraoperatively, and distances from defect margins to adjacent anatomical structures, such as root apices, mental foramen and inferior border of mandible, were assessed postoperatively on a panoramic radiograph. Results Pulp sensitivity changes were found in 18.6% of adjacent teeth at the time of suture removal. At the 6-month follow-up, 8.1% of teeth, and at the 12-month re-examination, 0.6% of teeth presented with altered sensitivity. This decrease over time of the number of affected teeth per patients with sensitivity changes was significant (P=2.35e-007). Lower lip hypaesthesia was only observed in one patient postoperatively, with complete resolution at the 6-month follow-up. Radiographic measurements of distances between donor defect and adjacent anatomical structures only reached significant difference for one parameter in patients with sensitivity changes compared with patients without sensitivity changes. Conclusions Patients must be informed about possible transient and long-term sensitivity changes of adjacent teeth and soft tissues following bone harvesting from the chin. However, by correctly placing mucoperiosteal incisions and bone cuts, the risk of sensitivity changes can be minimized.