Longitudinal analysis of microcirculatory parameters in gingival tissues after tooth extraction in patients with different risk profiles for wound healing disorders - a pilot study.

OBJECTIVES: We aimed to establish a risk profile for intraoral wound healing disorders based on measurements of microcirculation in gingival tissues. MATERIALS AND METHODS: Oxygen saturation (SO2) and blood flow in gingival tissues were measured with tissue spectrometry and laser doppler spectroscopy in 37 patients before/after tooth extractions. Patients were assigned to four groups: anamnestically and periodontally healthy patients (n = 7), anamnestically healthy but suffering from periodontitis (n = 10), anamnestically healthy but smoking and suffering from periodontitis (n = 10) and suffering from diabetes and periodontitis (n = 10). Measurements were performed at three different time points: Baseline measurement (T0), one day post extractionem (p.e.) (T1) and seven days p.e. (T2). RESULTS: Baseline SO2 values were higher in control patients (p = .038). This effect was most evident in comparison to smokers suffering from periodontitis (p = .042), followed by diabetics suffering from periodontitis (p = .09). An opposite trend was seen for blood flow. Patients suffering from periodontitis demonstrated higher blood flow values (p = .012). Five patients, which belonged to the group of smokers suffering from periodontitis, showed clinically a delayed wound healing. CONCLUSION: Differences in SO2 and blood flow of gingival tissue could be detected in different groups of patients with existing periodontitis compared to control patients. CLINICAL RELEVANCE: Lower baseline SO2 values could be a warning signal for possible wound healing disorders after oral surgery.

Determination of baseline alveolar mucosa perfusion parameters using laser Doppler flowmetry and tissue spectrophotometry in healthy adults.

Objectives: To determine the baseline perfusion parameters of the alveolar mucosa using laser Doppler flowmetry and tissue spectrophotometry (LDF-TS) in healthy adults.Material and methods: Forty-two healthy adult subjects of either sex were tested. The perfusion of the alveolar mucosa was evaluated using a laser Doppler flowmetry and tissue spectrophotometry using O2C 'oxygen to see' device. The measurements encompassed the maxillary and mandibular mucosa at 20 different points.Results: The O2C device is a reliable method for noninvasive measurement of different perfusion parameters of the oral mucosa. The hemoglobin saturation values (So2 in %), as well as relative amount of hemoglobin in arbitrary units (AU) of the maxillary mucosa demonstrated lower values of that in the mandible. The flow value (AU) exhibited a significant difference in the posterior molar region only, while the velocity value (AU) showed a significant difference across all points except for the anterior region.Conclusion: the present study provides a set of brand-new perfusion parameters of the microcirculation of the alveolar mucosa using LDF-TS. The study suggests a variation of the perfusion parameters between the maxilla and the mandible. Differences in the anatomy of the blood supply, the thickness of the mucosa and the cortical bone, may be attributed to this variation. Further studies using different probes and a combination of ultrasonic measurements and SDF imaging will aid in giving a better overview of the perfusion in the oral mucosa.

Characterization of a diet-induced obesity rat model for periodontal research.

OBJECTIVES: Obesity is associated with periodontitis, but the mechanisms underlying this association have yet to be unraveled. The present investigation was to evaluate a common rat model, in which obesity is induced by high-fat, high-sucrose diet (HFSD), for its applicability in periodontal research. MATERIALS AND METHODS: Ten male Wistar rats were fed a 3-month HFSD along with a matching control group. Afterwards, the body weight, adipocyte morphology, leptin and adiponectin levels in adipose tissue, gingiva, and serum as well as the serum levels of triglyceride, cholesterol, and glucose were analyzed. For statistical analyses, parametric and non-parametric tests were applied (p < 0.05). RESULTS: Body weight was significantly higher in the HFSD group after dieting as compared to control. HFSD caused a significant increase in serum triglyceride, low-density lipoprotein cholesterol, and leptin levels and a significant decrease in high-density lipoprotein cholesterol. Furthermore, adipose tissue from HFSD rats exhibited significantly larger adipocytes, displayed a significant upregulation of leptin and, surprisingly, elevated adiponectin levels, which is in contrast to chronic obesity in humans. Although leptin and adiponectin were also observed in gingival biopsies, no obvious differences between the groups were found. CONCLUSIONS: Although this rat diet-induced obesity model is characterized by changes typical of obesity, it also has limitations, which have to be considered when data, especially with regard to adipokines, are extrapolated to humans. CLINICAL RELEVANCE: The rodent diet-induced obesity model may be useful for unraveling pathomechanisms underlying the association between obesity and periodontal destruction but conclusions have to be drawn with caution.

Sika deer antler as a novel model to investigate dental implant healing: A pilot experimental study.

Dental implants are important tools for restoring the loss of teeth. The rapid growth and periodic regeneration of antlers make Sika deer a good and less invasive alternative model for studying bone remodelling in mammals. We developed a special loading device for antlers and analysed the bone reaction around unloaded implants and under immediate loading conditions until osseointegration occurred. In micro-computed tomography images, the density of antler tissue around the implants increased as the loading time increased. This finding was histologically confirmed by the good osseointegration observed in unloaded and loaded specimens. Antler tissue displays a similar healing process to human bone. The use of an antler model is a promising alternative for implant studies that does not require animal sacrifice.

Biomechanical characteristics of immediately loaded and osseointegration dental implants inserted into Sika deer antler.

This study aimed to compare biomechanical characteristics of immediately loaded (IL) and osseointegrated (OS) dental implants inserted into Sika deer antler and lay a foundation for developing an alternative animal model for dental implants studies. Two implants per antler were inserted. One implant was loaded immediately via a self-developed loading device; the other was submerged and unloaded as control. IL implants were harvested after different loading periods. The unloaded implants were collected after OS and the shedding of antler. Specimens were scanned by µCT scanner and finite element models were generated. A vertical force of 10 N was applied on the implant. The mean values of maximum displacements, stresses and strains were compared. The results showed that the density of antler tissue around the implants dramatically increased as the loading time increased. After shedding the antler, 3 pairs of antlers were collected and the density of antler tissue remained in a similar value in all specimens. The maximum values of displacement and stresses in implant and stresses and strains in antler tissue were significantly different among OS models. In one antler, all the biomechanical parameters of IL model were significantly higher than those of OS model of the same animal (P < 0.05) and wider distributions were obtained from IL model. It can be concluded that implants inserted into Sika deer antler might not disturb the growth and calcification process of antler and the use of Sika deer antler model is a promising alternative for implant studies that does not require animal sacrifice.

Numerical investigation of bone remodelling around immediately loaded dental implants using sika deer (Cervus nippon) antlers as implant bed.

This study combines finite element method and animal studies, aiming to investigate tissue remodelling processes around dental implants inserted into sika deer antler and to develop an alternative animal consuming model for studying bone remodelling around implants. Implants were inserted in the antlers and loaded immediately via a self-developed loading device. After 3, 4, 5 and 6 weeks, implants and surrounding tissue were taken out. Specimens were scanned by µCT scanner and finite element models were generated. Immediate loading and osseointegration conditions were simulated at the implant-tissue interface. A vertical force of 10 N was applied on the implant. During the healing time, density and Young's modulus of antler tissue around the implant increased significantly. For each time point, the values of displacement, stresses and strains in the osseointegration model were lower than those of the immediate loading model. As the healing time increased, the displacement of implants was reduced. The 3-week immediate loading model (9878 ± 1965 µstrain) illustrated the highest strains in the antler tissue. Antler tissue showed similar biomechanical properties as human bone in investigating the bone remodelling around implants, therefore the use of sika deer antler model is a promising alternative in implant biomechanical studies.

Incidence and severity of gingival invaginations associated with early versus late initiation of orthodontic space closure after tooth extraction : A multicenter pilot and randomized controlled trial.

OBJECTIVE: Gingival invaginations are a common side effect of orthodontic extraction-space closure. The timing of initiating the closure of an extraction space varies greatly in clinical practice. In this multicenter pilot and randomized controlled trial, we prospectively investigated whether initiating space closure in the early stage of wound healing would benefit the incidence and severity of invaginations developing in the extraction sites. METHODS: A total of 368 patients were screened for indications to extract at least one mandibular premolar. Those recruited were randomly assigned to one of two treatment arms: initiation of space closure either 2-4 weeks (arm A) or ≥12 weeks (arm B) after tooth extraction. Clinical data regarding treatment process and periodontal tissue response were recorded during and after space closure and analyzed by a specialized biometrics unit. The study was performed under continuous surveillance by an independent study control center. RESULTS: A total of 74 extraction sites were analyzed. Regarding the incidence of gingival invaginations, there were no significant intergroup differences [p = 0.13; group A comprising 37/44 (84.1%) and group B 29/30 (96.7%) invaginated sites]. The same was true based on either maxillary (p = 0.52) or mandibular (p = 0.21) sites only, and the severity of the invaginations did not differ between the treatment arms. CONCLUSIONS: As to the incidence and severity of gingival invaginations, we did not notice any statistically significant differences between the two timeframes. Our data do, however, provide a basis to identify additional confounders and to improve the accuracy of case-load estimations for future trials.

Immunohistochemical analysis of the gingiva with periodontitis of type I plasminogen deficiency compared to gingiva with gingivitis and periodontitis and healthy gingiva.

OBJECTIVE: Type I plasminogen deficiency (Plgdef) is an uncommon chronic inflammation of mucous membranes. Gingival enlargements usually proceed with progressive periodontal destruction and tooth-loss. Plasmin(ogen)-independent enzymatic mechanisms for fibrin clearance have already been discussed in the literature. Our primary objective was to verify, immunohistochemically, the occurrence of different enzymatic factors involved in tissue breakdown of inflamed compared to healthy gingiva. Secondly, we tried to find out, if these patients have a similar microbiological profile to the patients with known gingivitis and periodontitis. MATERIALS AND METHODS: Immunohistochemical analysis of enzymes elastase, plasminogen (plg), cathepsin G, matrix-metalloproteinase (MMP)-3 and MMP-7 and of glycoprotein fibrinogen were performed with gingival tissues from 3 healthy controls, 8 patients with Plgdef and 3 patients with gingivitis and periodontitis. Furthermore, plaque from 5 patients with plasminogen deficiency were also obtained to determine the microbiological profile. RESULTS: Significantly high numbers of elastase positive leukocytes were detected in all samples. Staining for MMP-3 and MMP-7 was seen in samples with gingivitis and periodontitis with a stronger staining in samples with periodontitis by Plgdef. Fibrinogen was detectable in all samples. Staining for plg was stronger in samples with periodontitis than in other samples. Staining for cathepsin G was weak in gingivitis and periodontitis. Subgingival microbial flora showed elevated colony forming units of Prevotella intermedia/nigrescens, Fusobacterium spp., Eikenella corrodens, Porphyromonas gingivalis and viridans streptococci. CONCLUSION: Strong staining of elastase, MMP-3 and MMP-7 and weak staining of plg in Plgdef samples supports the plasmin(ogen) - independent fibrin clearance. Similar subgingival microbiological flora was observed in periodontitis with Plgdef as in other periodontal diseases. Further investigations should determine the exact pathomechanism and focus on effective treatment methods of this entity.

Long-term effects of vertical bone augmentation: a systematic review.

UNLABELLED: Extraction, periodontitis, or trauma can cause a reduction on the alveolar ridge. This could result in an insufficient alveolar bone width and height. Different techniques of vertical bone augmentation are described in literature. However, nowadays there is not enough evidence against lateral augmentation procedures to verify if these techniques are stable over a long period of time. OBJECTIVE: This review analyses the different techniques that are used to vertically augment the bone and evaluate if these techniques are stable over a long period of time. MATERIAL AND METHODS: The MEDLINE-PubMed database was searched from its earliest records until December 22, 2014. The following search term was used: Alveolar Ridge augmentation [MESH]. Several journals were hand searched and some authors were contacted for additional information. The primary outcome measure that was analyzed was marginal bone level change around dental implants in the augmented sites, and the secondary outcomes were survival and success rates of dental implants placed in the augmented sites. RESULTS: The search yielded 203 abstracts. Ultimately, 90 articles were selected, describing 51 studies meeting the eligibility criteria. The marginal bone level change for the inlay technique and vertical guided bone regeneration are in agreement with the success criteria. Alveolar distraction showed more marginal bone level change after the first year of loading, and for the inlay technique very few studies were available. CONCLUSIONS: Based on the available data in the current existing studies with a follow-up period of at least 4 to 5 years, one can summarize that there seems to be a trend that the onlay technique, alveolar distraction, and vertical guided bone regeneration are stable for at least 4 to 5 years.

Long-term effects of vertical bone augmentation: a systematic review

ABSTRACT Extraction, periodontitis, or trauma can cause a reduction on the alveolar ridge. This could result in an insufficient alveolar bone width and height. Different techniques of vertical bone augmentation are described in literature. However, nowadays there is not enough evidence against lateral augmentation procedures to verify if these techniques are stable over a long period of time. Objective This review analyses the different techniques that are used to vertically augment the bone and evaluate if these techniques are stable over a long period of time. Material and Methods The MEDLINE-PubMed database was searched from its earliest records until December 22, 2014. The following search term was used: Alveolar Ridge augmentation [MESH]. Several journals were hand searched and some authors were contacted for additional information. The primary outcome measure that was analyzed was marginal bone level change around dental implants in the augmented sites, and the secondary outcomes were survival and success rates of dental implants placed in the augmented sites. Results The search yielded 203 abstracts. Ultimately, 90 articles were selected, describing 51 studies meeting the eligibility criteria. The marginal bone level change for the inlay technique and vertical guided bone regeneration are in agreement with the success criteria. Alveolar distraction showed more marginal bone level change after the first year of loading, and for the inlay technique very few studies were available. Conclusions Based on the available data in the current existing studies with a follow-up period of at least 4 to 5 years, one can summarize that there seems to be a trend that the onlay technique, alveolar distraction, and vertical guided bone regeneration are stable for at least 4 to 5 years.

Correlation between peri-implant sulcular fluid rate and expression of collagenase2 (MMP8).

OBJECTIVES: The rapidly increasing numbers of inserted dental implants and the growing incidence of peri-implant mucositis and peri-implantitis with the current absence of reliable disease risk prediction highlight the importance of early and sensitive diagnosis of possible disease progression. The aim of this study is to assess quantitative and qualitative analysis of peri-implant sulcular fluid (PISF) during implant maintenance control and to identify whether there is a positive correlation and statistical significance between peri-implant sulcular fluid volume results and collagenase2 level obtained from both superficial and fundus area of peri-implant sulcus. MATERIAL AND METHOD: Twenty-seven implants from patients under recall provided peri-implant sulcular fluid volume samples, which were collected with the Periotron 8000 micro-moisture meter, and collagenase2 levels, which were assessed using dentoTest aMMP8. Statistical analysis was obtained using Spearman's correlation. RESULTS: Positive correlation was found between collagenase2 collected from sulcular and fundus areas on both mesial and distal sides. There was correlation between peri-implant sulcular fluid volume and collagenase2 level from fundus and distal area, but not from the mesial and superficial area. CONCLUSIONS: Examination of collagenase2 is a sensitive method when examining early inflammatory changes but depends from the depth of the sample collection in the gingival pocket. CLINICAL RELEVANCE: The examination of MMP8 seems to be a more sensitive method than the analysis of peri-implant sulcular fluid to detect peri-implant mucositis and peri-implantitis.

Pilot study of laser-doppler flowmetry measurement of oral mucosa blood flow / 北京大学学报(医学版)

Objective:To explore and compare the perfusion pattern of oral mucosa on Han Chinese and Caucasian by laser-doppler flowmetry.Methods:A cross-sectional study was carried out,in 20 healthy Han Chinese adult subjects (average age:28.4 years)and 20 healthy Caucasian (average age:25.3 years)adult subjects,either gender with 10 subjects.Gingival perfusion was evaluated at 8 points (including upper incisor labial gingival,lower incisor labial gingival,palatal mucosa,cheek mucosa) using a laser-doppler flowmetry(O2C,Medizintechnik GmbH,Germany).Each measurement was car-ried out 25 seconds consisting 5 seconds of foreperiod and 20 seconds of work period,without pressure. The measurements were taken by two well-trained doctors,each measurement was exammed 3 times by an examiner,and the average value was recorded as final data.Each measurement has 4 parame ters:SpO2 (oxygen saturation),rHB (relative amount of hemoglobin),flow (the blood flow of unit interval),and velocity (blood flow velocity).We compared the data by different sites,different genders,and different races.Results:For palatal gingival,the average SpO2 was 77.1% ±10.9%,the average rHB 67.8 ± 11.1,and the average flow 194.1 ±63.7,which presented significant lower values than other oral muco-sa.There was no significant difference among other sites.There was some significant difference between the Caucasian and the Han Chinese:the maxillary central incisor oxygen saturation (SpO2)which were averages of 75.6% ±8.2% and 70.4% ±7.6%;buccal mucosa hemoglobin (rHB)averages of 79.9 ±5.8 and 83.5 ±6.6,which had statistical differences.For most measurement points,the oxygen saturation on men was lower than that on women,which had significant difference.Conclusion:To inves-tigate microcirculation pattern,oral mucosa can be the good observation site.Laser-doppler flowmetry is a well-documented instrument to survey on microcirculation.There may be differences between the genders in hemoglobin oxygen-binding capacity,which may have some impact on the ability of soft tissue healing. Oral mucosa display more blood perfusion than attached gingival.As the recipient site of gingival graft, maxilla and mandible have slight difference in blood supply.

The Use of High-Frequency Ultrasound in the Measurement of Thickness of the Maxillary Attached Gingiva.

PURPOSE: Ultrasonography has been extensively explored in dentistry because of its several diagnostic advantages. The purpose of this study was to determine the thickness of the maxillary attached gingiva with the use of a high-frequency ultrasound in subjects with sex-, age- and smoking-related differences. MATERIALS AND METHODS: A total of 100 healthy subjects (70 women and 30 men, age range: 18 to 55 years) were included. A special B-scan unit was used to measure the soft tissue thickness in the buccal and palatal attached gingiva in the maxillary arch. Aquasonic 100 Ultrasound Gel (Parker Laboratories) was used as coupling medium. Student t test was used for statistical analysis of the subgroups with different parameters with significance set at P<.05. RESULTS: A total of 2,734 measurements showed that male nonsmokers have a significantly thicker fixed gingiva than nonsmoking women and that age does not seem to have great influence on the thickness of the gingiva. Smoking had a significant effect, but only on the oral maxillary gingival tissues of women. The palatal gingiva was found to be significantly thicker in female smokers than in nonsmoking females. CONCLUSIONS: Measurement of gingival thickness for different purposes using a B-scan ultrasonic device appears to be a reliable method. Sex- and smoking-related differences in the gingival thickness exist only on the palatal side among women.

Recurrent squamous odontogenic tumor: A case report and review of the literature.

Squamous odontogenic tumors (SOTs) are benign, locally infiltrative neoplasms that localize to the periodontium. In total, <50 cases have been reported since the first description of SOTs in 1975. Although the exact etiology of SOTs is unknown, the tumors are considered to derive from the epithelial cell rests of Malassez. SOTs are characterized by radiological and clinical signs and symptoms, including pain with increased sensitivity in the affected area, bone expansion and increased tooth mobility. The present study describes the case of a patient that experienced numerous SOT recurrences and also discusses recommendations for treatment. A locally invasive mandibular SOT was identified in a Caucasian 41-year-old female patient. The treatment involved recommended conservative surgery, including local curettage. In addition, 49 cases published in the literature were reviewed to assess the treatment strategies. The present patient experienced two recurrences of the tumor during the 6-year follow-up period. Ultimately, the vitality of the adjacent teeth was compromised. An apicoectomy with a small amount of resection of the marginal bone was necessary. In >50% of the reported cases of SOT in the literature the adjacent teeth were extracted. The present case of SOT and the associated literature were also discussed. It was concluded that the treatment of choice appears to be a conservative surgical removal, but the successful management of SOTs often requires the removal of the adjacent teeth.

Regulation of NAMPT in human gingival fibroblasts and biopsies.

Adipokines, such as nicotinamide phosphoribosyltransferase (NAMPT), are molecules, which are produced in adipose tissue. Recent studies suggest that NAMPT might also be produced in the tooth-supporting tissues, that is, periodontium, which also includes the gingiva. The aim of this study was to examine if and under what conditions NAMPT is produced in gingival fibroblasts and biopsies from healthy and inflamed gingiva. Gingival fibroblasts produced constitutively NAMPT, and this synthesis was significantly increased by interleukin-1ß and the oral bacteria P. gingivalis and F. nucleatum. Inhibition of the MEK1/2 and NFκB pathways abrogated the stimulatory effects of F. nucleatum on NAMPT. Furthermore, the expression and protein levels of NAMPT were significantly enhanced in gingival biopsies from patients with periodontitis, a chronic inflammatory infectious disease of the periodontium, as compared to gingiva from periodontally healthy individuals. In summary, the present study provides original evidence that gingival fibroblasts produce NAMPT and that this synthesis is increased under inflammatory and infectious conditions. Local synthesis of NAMPT in the inflamed gingiva may contribute to the enhanced gingival and serum levels of NAMPT, as observed in periodontitis patients. Moreover, local production of NAMPT by gingival fibroblasts may represent a possible mechanism whereby periodontitis may impact on systemic diseases.

Implant-supported mandibular overdentures and cortical bone formation: clinical and radiographic results.

PURPOSE: The aim of this study was to evaluate the hard and soft tissue parameters around implants supporting overdentures and the possible influence of increased periimplant bone density (IPBD) on implant success. MATERIALS AND METHODS: A total of 44 dental implants placed in the mandible of 12 patients were included in the study. Implants were divided in 2 groups in relation to the optically detected IPBD. Periimplant clinical and radiographic variables were collected over the period of 5 years. RESULTS: Periimplant clinical and radiographic parameters for all implants did not change significantly throughout the observation period (P > 0.05). Significant differences were observed between implants with and without IPBD for periimplant soft tissue parameters and Periotest values (P < 0.05). Implants with and without IPBD at 5-year control showed mean bone loss of 0.04 ± 0.48 mm and 0.55 ± 0.96 mm, respectively (P = 0.026). All density values decreased throughout the observation period, except maximal values for implants with IPBD that overcome the initial values at the 5-year control. CONCLUSIONS: Implants supporting overdentures were clinically successful over the period of follow-up. IPBD may be related to the maintenance of the periimplant bone level.

Comparison of the accuracy of cone beam computed tomography and medical computed tomography: implications for clinical diagnostics with guided surgery.

PURPOSE: This study compared the accuracy of cone beam computed tomography (CBCT) and medical-grade CT in the context of evaluating the diagnostic value and accuracy of fiducial marker localization for reference marker-based guided surgery systems. MATERIALS AND METHODS: Cadaver mandibles with attached radiopaque gutta-percha markers, as well as glass balls and composite cylinders of known dimensions, were measured manually with a highly accurate digital caliper. The objects were then scanned using a medical-grade CT scanner (Philips Brilliance 64) and five different CBCT scanners (Sirona Galileos, Morita 3D Accuitomo 80, Vatech PaX-Reve3D, 3M Imtech Iluma, and Planmeca ProMax 3D). The data were then imported into commercially available software, and measurements were made of the scanned markers and objects. CT and CBCT measurements were compared to each other and to the caliper measurements. RESULTS: The difference between the CBCT measurements and the caliper measurements was larger than the difference between the CT measurements and the caliper measurements. Measurements of the cadaver mandible and the geometric reference markers were highly accurate with CT. The average absolute errors of the human mandible measurements were 0.03 mm for CT and 0.23 mm for CBCT. The measurement errors of the geometric objects based on CT ranged between 0.00 and 0.12 mm, compared to an error range between 0.00 and 2.17 mm with the CBCT scanners. CONCLUSIONS: CT provided the most accurate images in this study, closely followed by one CBCT of the five tested. Although there were differences in the distance measurements of the hard tissue of the human mandible between CT and CBCT, these differences may not be of clinical significance for most diagnostic purposes. The fiducial marker localization error caused by some CBCT scanners may be a problem for guided surgery systems.

Clinical and radiographic outcome of dental implants supporting fixed prostheses: the relevance of cortical bone formation.

PURPOSE: To evaluate the hard and the soft tissue parameters around implants supporting fixed prostheses over a period of 5 years and the possible association to the increase in periimplant bone density (IPBD). MATERIAL AND METHODS: A total of 39 dental implants placed in 29 patients were included in the study. Periimplant clinical (gingival index, probing depth, keratinized mucosa, sulcus fluid flow rate) and radiographic variables (bone loss, bone density) were collected, and the data analysis performed. RESULTS: Periimplant hard and soft tissue parameters remained stable throughout the follow-up period. Of the 39 implants, 20 demonstrated IPBD. The mean distance between first bone-to-implant contact and the microgap for implants with and without IPBD was significantly different at 1-year, 2-year, and 5-year follow-up. The evidence of IPBD demonstrated no influence on the periimplant soft tissue parameters. All mean values of bone density for implants with IPBD were higher than those for implants without IPBD throughout the whole observation period. CONCLUSION: All implants were clinically successful over the period of follow-up. IPBD might be more indicative of a stable periimplant bone level.

Application and success of two stereolithographic surgical guide systems for implant placement with immediate loading.

PURPOSE: Two different stereolithographic surgical guide systems, NobelGuide (Nobel Biocare) and SimPlant (Materialise), were compared clinically, and the survival rates of the planned immediately loaded dental implants with prefabricated provisional restorations were evaluated. MATERIALS AND METHODS: Patients were treated with implants using either the Materialise SimPlant system or the Nobel Biocare system. All implants were planned on cone beam computed tomography (CBCT) or CT-derived images. Mucosa-, bone-, or tooth-supported stereolithographic guides were produced using the two commercial systems. A provisional was placed immediately after implant insertion in all cases. RESULTS: Fourteen patients were enrolled. Seventy-five implants were placed (34 with Materialise, 41 with Nobel Biocare) using stereolithographic surgical guides. All but one implant were loaded immediately with prefabricated provisionals. In all cases, implants were in place for a minimum of 12 months. No complications related to associated anatomy occurred. One implant failed, leading to a combined cumulative survival rate of 98.7%. There were no other intraoperative or postoperative complications. Implants placed by bone-supported guides had increased patient symptoms of postoperative swelling and discomfort. All provisionals were successful. CONCLUSIONS: Both types of stereolithographic surgical templates were sufficiently accurate in transferring the planned implant positions to the surgical field, allowing the placement of prefabricated provisionals. These technologies are most beneficial in patients in whom the simultaneous placement of multiple implants in combination with complex restorations is planned.