Bone regeneration after maxillary sinus floor augmentation with different ratios of autogenous bone and deproteinized bovine bone mineral an in vivo experimental study.

OBJECTIVE: Test the hypothesis of no difference in bone regeneration after maxillary sinus floor augmentation (MSFA) with different ratios of iliac or mandibular autogenous bone (AB) graft and deproteinized bovine bone mineral (DBBM). MATERIALS AND METHODS: Forty minipigs were randomly allocated to bilateral MSFA using: (A) 100% AB, (B) 75% AB and 25% DBBM, (C) 50% AB and 50% DBBM, (D) 25% AB and 75% DBBM, or (E) 100% DBBM. The animals were euthanized 12 weeks after surgery. Percentage of bone, non-mineralized tissue, and residual DBBM were estimated by histomorphometric analysis in a randomly selected region of interest and summarized as mean percentage with 95% confidence interval (CI). RESULTS: Mean percentage of bone following MSFA with iliac or mandibular AB graft was: (A) 55.5% and 64.2%, (B) 60.3% and 61.6%, (C) 54.4% and 52.1%, (D) 51.8% and 53.1%, and (E) 47.6%, respectively. There was a significant trend toward a higher percentage of bone, with a higher ratio of AB within the graft (p < .01), regardless of the origin of AB graft (iliac or mandible). CONCLUSIONS: The hypothesis was rejected since percentage of bone was significantly increased with larger proportions of AB within the graft. Consequently, AB or a mixture of AB and diminutive quantities of DBBM seem to be the preferred graft for MSFA based solely on histomorphometric assessment. However, it should be emphasized that newly formed bone and residual AB graft particles could not be distinguished by the applied histologic procedure.

Professional and patient-reported outcomes of two surgical approaches for implant-supported single-crown restoration: 1-year results of a randomized controlled clinical trial.

OBJECTIVES: To test whether there is a difference in professional and patient-reported outcome measures (PROM) after single-crown restoration supported by short implants (SI) (6 mm) compared with standard length implants (SLI) (13 mm) in conjunction with maxillary sinus floor augmentation (MSFA) after 1 year of functional implant loading. MATERIAL AND METHODS: Forty patients were randomly allocated to SI or SLI/MSFA. PROM included Oral Health Impact Profile (OHIP-14) questionnaire and subjective assessment of the peri-implant soft tissue (A), implant crown (B), implant function (C) and overall implant treatment outcome (D) using visual analogue scale (VAS). Professional assessment included pink aesthetic score (PES) and white aesthetic score (WES). RESULTS: No significant differences in professional or PROM between the two treatment modalities were revealed at any time point (p > .05). OHIP-14 score decreased at baseline and 1 year after functional implant loading compared with preoperative measurements indicating improved quality of life with both treatment modalities. The 1-year mean VAS score was 9.4 (A), 9.3 (B), 9.6 (C) and 9.3 (D) for SI compared with 9.3 (A), 9.6 (B), 9.7 (C) and 9.2 (D) for SLI. The 1-year mean PES/WES scores were 11.3 and 8.1 for SI compared with 11.2 and 8.1 for SLI/MSFA. CONCLUSIONS: Prosthetic rehabilitation of the posterior part of the maxilla with SI or SLI/MSFA revealed no significant differences in professional and PROM after 1 year of implant loading.

Soft tissue management at implants: Summary and consensus statements of group 2. The 6th EAO Consensus Conference 2021.

OBJECTIVES: The task of working Group 2 at the 6th Consensus Meeting of the European Association for Osseointegration was to comprehensively assess the effects of soft tissue augmentation procedures at dental implant sites on clinical, radiographic and patient-reported outcome measures (PROMs) including an overview on available outcome measures and methods of assessment. MATERIALS AND METHODS: Three systematic reviews and one critical review were performed in advance on (i) the effects of soft tissue augmentation procedures on clinical, radiographic and aesthetic outcomes, (ii) reliability and validity of outcome measures and methods of assessment and (iii) PROMs applied in clinical studies for soft tissue augmentation procedures at dental implant sites. Major findings, consensus statements, clinical recommendations and implications for future research were discussed in the group and approved during the plenary sessions. RESULTS: The four reviews predominantly revealed: Soft tissue augmentation procedures in conjunction with immediate and delayed implant placement result in superior aesthetic outcomes compared to no soft tissue augmentation in the zone of aesthetic priority. Soft tissue augmentation procedures have a limited effect on marginal bone level changes compared to implant sites without soft tissue augmentation. Clinically relevant parameters (gingival index, mucosal recession) and plaque control improve at implant sites when the width of keratinised mucosa is increased. A variety of aesthetic indices have been described with good reliability. Pink Esthetic Score and Complex Esthetic Index are the most validated aesthetic indices for single implants, though. Superimposed digital surface scans are most accurate to assess profilometric tissue changes. PROMs following soft tissue augmentation procedures have been assessed using various forms of questionnaires. Soft tissue augmentation had a limited effect on PROMs. CONCLUSIONS: Soft tissue augmentation procedures are widely applied in conjunction with implant therapy. Depending on the indication of these interventions, clinical, radiographic and aesthetic outcomes may improve, whereas the effect on PROMs is limited.

Histology of augmented autogenous bone covered by a platelet-rich fibrin membrane or deproteinized bovine bone mineral and a collagen membrane: A pilot randomized controlled trial.

OBJECTIVES: This study aimed to evaluate histologic and histomorphometric bone characteristics with a focus on vitality after lateral alveolar ridge augmentation using an autogenous bone graft as a block covered by either a platelet-rich fibrin (PRF) membrane (test group) or a standard procedure involving coverage of the bone block with a deproteinized bovine bone mineral and a resorbable collagen membrane (control group). MATERIAL AND METHODS: A total of 27 (test = 14, control = 13) partially edentulous patients with indication for bone block augmentation before implant installation were included. For analyses, a biopsy of augmented bone was retrieved six months after bone grafting. RESULTS: Histologic evaluation of augmented bone revealed a predominance of non-vital bone toward the periosteum and few localized areas of vital bone in the center of the graft in both groups. In contrast, augmented bone toward the native bone demonstrated extensive bone remodeling in both groups. Histomorphometric analyses demonstrated a mean of 14% vital bone, 80% non-vital bone, 5% soft tissue, and 1% blood vessels in the test group. In the control group, the corresponding shares were 14% vital bone, 63% non-vital bone, 22% soft tissue, and 1% blood vessels. We observed no significant differences between the groups (p > .05). CONCLUSION: In conclusion, a comparable low bone vitality of augmented bone was observed in the PRF and in the control group. Consequently, the present study could not verify the potential beneficial effect of a PRF membrane on bone vitality of an autogenous bone graft used as a block.

Cone beam computed tomography evaluation of staged lateral ridge augmentation using platelet-rich fibrin or resorbable collagen membranes in a randomized controlled clinical trial.

OBJECTIVES: To evaluate the volumetric changes following lateral alveolar ridge augmentation using autogenous bone graft covered by either a platelet-rich fibrin membrane (test group) or an inorganic bovine bone substitute and a resorbable collagen barrier membrane (control group). MATERIAL AND METHODS: A total of 27 partially edentulous patients (test n = 14, control n = 13) with the indication for lateral bone block augmentation were included in this randomized, controlled clinical trial. Cone beam computed tomography (CBCT) examination was performed prior to grafting and 2 weeks and 6 months after grafting. The volumetric changes between the various examinations times were evaluated by planimetric measurements on two-dimensional CBCT images of the grafted regions. RESULTS: The mean bone volumetric loss in the test group was 14.7%, SD ±8.9%, while the mean bone volume loss in the control group was 17.8%, SD ±13.3%. This difference was not significant (p = 0.48). A total of ten patients were operated in the incisor and canine region with a mean bone volume loss of 23.41% SD, ±10.87%, while 17 patients were operated in the premolar region with a mean bone volume loss of 11.89% SD ±9.05%. This difference was significant (p = 0.01). CONCLUSION: The test and control group demonstrated no overall difference in volumetric bone changes of the augmented bone at the 6-month follow-up. The second major finding revealed a significantly larger amount of bone resorption in the incisor and canine region than in the premolar region of the maxilla, particularly in the control group.

Drugs and diseases: Summary and consensus statements of group 1. The 5th EAO Consensus Conference 2018.

OBJECTIVES: The task of this working group was to update the knowledge about the use of drugs and biologicals affecting healing of soft tissue and bone during implant treatment or procedures associated with it. Moreover, the impact of titanium particles and biocorrosion on complications and implant survival has been analysed. MATERIALS AND METHODS: The literature in the areas of interest (platelet concentrates, antiresorptive drugs as well as implant-host interaction) was screened using systematic reviews for the former two areas, whereas a narrative critical review was performed for the latter topic. Two manuscripts on platelet concentrates, one manuscript on antiresorptive drugs and one manuscript on the effects of biocorrosion, were presented for group analysis with subsequent discussion in the plenum and final consensus approval. RESULTS: Results and conclusions of the individual reviews of the three topics are presented in the respective papers. Conclusions of the group on strengths and weaknesses of available evidence as well as consensus statements and directions for further research are provided in this study. The following papers were subject to group discussions and formed the basis for the consensus statements: Stähli A, Strauss FJ, Gruber R. () The use of platelet-rich-plasma to enhance the outcomes of implant-related therapies: a systematic review Strauss FJ, Stähli A, Gruber R. (2018) The use of platelet-rich-fibrin to enhance the outcomes of implant-related therapies: a systematic review Mombelli A, Hashim D, Cionca N. () What is the impact of titanium particles and bio-corrosion on implant survival and complications? A critical review Stavropoulos A, Bertl K, Pietschmann P, Pandis N, Morten Schiødt, Klinge B. () The effect of antiresorptive drugs on implant therapy: a systematic review.

Periodontitis in patients with cirrhosis: a cross-sectional study.

BACKGROUND: Many patients with cirrhosis have poor oral health but little is known on periodontitis, and its clinical significance is largely unknown. This study aimed to examine the prevalence and predictors of periodontitis, and evaluate the association of periodontitis with nutritional and systemic inflammation status. METHODS: 145 patients with cirrhosis were consecutively enrolled. Clinical, oral examination of plaque, pocket depth, clinical attachment level, and bleeding on probing was performed. Patients were categorized as having no-or-mild, moderate, or severe periodontitis. Predictors of severe periodontitis and the association with nutritional and systemic inflammation status were analyzed using univariable and multivariable logistic regression analyses. RESULTS: The large majority of patients had periodontitis, 46% of them severely and 39% moderately. Predictors of severe periodontitis included smoking (odds ratio (OR) 2.93, 95% confidence interval (CI) 1.29-6.63), brushing teeth twice daily (OR 0.30, 95% CI 0.11-0.79), and visiting the dentist annually (OR 3.51, 95% CI 1.22-10.81). Cirrhosis etiology or severity was not predictors of severe periodontitis. The patients with severe periodontitis had a higher nutritional risk score than patients with moderate, mild, or no periodontitis (3, interquartile range (IQR) 3-5 vs. 3, IQR 2-4, P = 0.02). CONCLUSIONS: Most cirrhosis patients had significant periodontitis, the severity of which was related to life style factors and was associated with higher nutrition risk score. Our results emphasize the need for further research to establish the effect of periodontitis on cirrhosis.

Maxillary Sinus Membrane Elevation With Simultaneous Installation of Implants Without the Use of a Graft Material: A Systematic Review.

OBJECTIVE: To compare implant treatment outcome after maxillary sinus membrane elevation with simultaneous installation of implants with or without the use of graft material applying the lateral window technique. MATERIALS AND METHODS: MEDLINE/PubMed, Cochrane Library, and Embase search in combination with a hand-search of relevant journals was conducted from January 1, 2004 to January 1, 2016. RESULTS: Thirteen studies fulfilled the inclusion criteria. Survival of suprastructures has not been compared within the same study. Short-term implant survival without graft material varied between 96% and 100% compared to 100% for autogenous bone or bone substitutes. No significant difference in bone gain was reported without graft material compared to autogenous bone. The density of newly formed bone increased significantly during the observation period. Bone density was significantly higher in sinuses augmented with blood clot compared to bone substitute, whereas no significant difference was found when compared to autogenous bone. Noncomparative studies demonstrated high long-term implant survival and new bone formation after sinus membrane elevation without graft material. CONCLUSIONS: Sinus membrane elevation without the use of a graft material seems to enhance new bone formation with high implant survival, but long-term comparative studies are missing.

Factors influencing severity of peri-implantitis.

OBJECTIVES: To retrospectively assess the influence of potential risk factors, primarily smoking and a prior history of periodontitis, on the severity of peri-implantitis in patients referred for treatment of peri-implantitis. MATERIALS AND METHODS: Among 98 patients referred for treatment of peri-implantitis, 34 patients fulfilled the inclusion criteria: one or several implants with peri-implant marginal bone loss ≥2 mm concomitant with bleeding and/or pus on probing. Information about health status, smoking habits, reason for tooth loss, and performed implant treatment were obtained from the patient charts and interviews. Moreover, a detailed extra- and intraoral examination was performed, including intraoral radiographs of all implants. Risk factors were evaluated by a two-way anova at patient level. RESULTS: Smoking and a prior history of periodontitis were significant risk factors for increased severity of peri-implantitis. Furthermore, the presence of both smoking and a prior history of periodontitis did not further increase the severity of peri-implantitis, as compared to either of these two factors alone. Poor marginal fit of the suprastructure and extensive gingival imitations on implant-supported fixed full prostheses may also be potential risk factors. CONCLUSIONS: The study indicated that smoking and a prior history of periodontitis were important risk factors for increased severity of peri-implantitis, while concomitant presence of these two risk factors did not further increase the severity of peri-implantitis, as compared to either of these two risk factors alone. Therefore, early diagnosis and adequate treatment of peri-implantitis are important in patients with a prior history of periodontitis and in smokers to minimize the risk of advanced peri-implantitis in conjunction with focus on known risk factors, including meticulous infection control before implant treatment and a systematic maintenance care program.

Effects of TNF-α blocking on experimental periodontitis and type 2 diabetes in obese diabetic Zucker rats.

OBJECTIVE: Tumour necrosis factor α (TNF-α) is considered a key signalling modulator in the pathogenesis of both periodontitis (PD) and type 2 diabetes mellitus (DM2). This study aims at elucidating the effect of TNF-α blocking on the interplay between PD and DM2. METHODS: Obese diabetic Zucker rats and their lean littermates were divided into five treatment groups with or without periodontitis. Anti-TNF-α treatment was provided with Etanercept injections. Diabetic state was evaluated by oral glucose tolerance test, the homeostatic model assessment, free fatty acids and blood glucose. Systemic inflammation was assessed by measurement of interleukin (IL)-1ß, IL-6 and TNF-α in plasma. Kidney complications were evaluated by real-time rtPCR, creatinine clearance rate, urinary albumin excretion and increase in weight. PD was evaluated by registration of alveolar bone level. RESULTS: After 4 weeks the diabetic state was modified by Etanercept treatment with lower insulin levels and lower homeostatic model assessment. Furthermore, while kidney complications were reduced by Etanercept treatment, PD had no effect. PD was influenced by diabetic state, but the impact was attenuated by Etanercept treatment. CONCLUSION: In this study anti-TNF-α treatment improved glucose tolerance and compensated for the increased periodontal disease in obese diabetic Zucker. PD did not influence diabetic parameters assessed including complications of the rats kidneys.

Patient satisfaction and esthetic outcome after immediate placement and provisionalization of single-tooth implants involving a definitive individual abutment.

OBJECTIVES: To assess patient satisfaction and esthetic outcome after immediate placement and provisionalization of single-tooth implants involving a definitive individual abutment and a provisional crown followed by later placement of a definitive crown. MATERIALS AND METHODS: In private practice, a single-tooth implant was placed immediately after tooth extraction in the esthetic zone of 54 patients. A definitive individual abutment and a provisional crown were mounted in the same visit. The definitive crown was placed after a mean period of 7 months. After a mean follow-up period of 33 months, the subjective and professional evaluation of the total implant treatment, peri-implant soft tissues, and implant crown were assessed on a 10-cm visual analog scale (VAS). The professional esthetic treatment outcome was also evaluated using pink esthetic score (PES), white esthetic score (WES), and total score of PES/WES. RESULTS: The evaluation of total implant treatment, peri-implant soft tissues, and implant crown demonstrated a significantly higher subjective than professional score for all 3 parameters (P < 0.001), for example, for the overall treatment, the mean scores were 9.4 and 7.0, respectively. A significant positive correlation was revealed between the professional VAS scores and the PESs and WESs. CONCLUSIONS: Immediate placement and provisionalization of single-tooth implants involving a definitive individual abutment and provisional crown followed by later placement of a definitive crown demonstrated high subjective and professional satisfaction. Generally, the professionals seem to be more critical than the patients. A strong correlation was observed between the professional VAS scores and the PES and WES scoring systems.

Is thermography useful for assessment of postoperative inflammation after surgical removal of mandibular third molars when methylprednisolone is administered and how does it correlate with patients' perception of swelling?

PURPOSE: To assess the differences in facial skin temperature after mandibular third molar removal when patients received methylprednisolone and placebo, respectively and to assess the correlation between patient-reported swelling using a visual analog scale (VAS) and facial skin temperature measured using thermography. PATIENTS AND METHODS: The study involved patients with 2 mandibular third molars with an indication for removal. The patients received either methylprednisolone or placebo in a randomized, crossover study design. Thermograms and the swelling VAS score were recorded 2 days after surgery. The outcome variable was the temperature difference (Δt) between the operated and control sides. A 2-sample t test analyzed the difference in Δt between the first and second operations. Spearman's rank correlation analysis was used to assess the correlation between the swelling VAS scores and the Δt. RESULTS: A total of 124 patients (67 males, 57 females, mean age 25 years) had both mandibular third molars removed on 2 separate occasions. No difference in Δt was found when methylprednisolone and placebo were given (P = .07). In addition, the correlation between the swelling VAS score and Δt was 0.30 (P = .001) and 0.09 (P = .3) after the first and second operation, respectively. CONCLUSIONS: Thermography does not seem sensitive enough to detect differences in the inflammatory response when patients received methylprednisolone or placebo. The correlation between the Δt and patient-reported swelling was low (≤0.3).

Immediate placement and provisionalization of single-tooth implants involving a definitive individual abutment: a clinical and radiographic retrospective study.

AIM: To assess with a mean follow-up period of 33 months (median: 31 month, range: 11-89 month) the treatment outcome after immediate placement and provisionalization of single-tooth oral implants involving a definitive individual abutment and a provisional crown followed by later placement of a definitive crown. MATERIALS AND METHODS: 68 patients with 68 single-tooth implants in the esthetic zone were consecutively treated; 55 of these patients were included in the study. The treatment involved tooth extraction, implant placement, placement of a definitive individual abutment, and a provisional crown in the same visit in private practice. The definitive crown was placed after a mean period of 7 months. The primary outcome measures included implant survival, definitive implant crown survival, and overall treatment survival. The secondary outcome measures included probing depth, bleeding on probing, peri-implant marginal bone level, marginal bone level of the neighboring tooth surfaces, biological complications, and technical complications. RESULTS: Of the inserted implants 98% survived and of the definitive crowns mounted a survival of 100% was observed. Consequently, the overall treatment survival was 98%. The mean probing depth was 2.9 mm at implant level and 63% of the implants were characterized by no bleeding on probing. The mean peri-implant marginal bone level was 2 mm. A significant mean peri-implant marginal bone level gain of 0.5 mm was observed from implant placement to the follow-up (95% CI: 0.07-0.89 mm, P = 0.022). No significant changes of the marginal bone level at the neighboring tooth surfaces were seen. Four episodes of peri-implant inflammation were identified in three patients, while 46 incidents of loosening of the provisional crown occurred in 33 patients. One abutment screw loosened before placement of the definitive crown. Finally, loosening of four definitive crowns occurred in four patients. CONCLUSIONS: Immediate placement and provisionalization of single-tooth oral implants involving a definitive individual abutment and a provisional crown followed by later placement of a definitive crown were characterized by high survival of the implant crowns and implants as well as healthy peri-implant tissues, after a mean follow-up period of 33 months. Loss of retention of the provisional crown occurred frequently.

Bone-to-implant contact after maxillary sinus floor augmentation with Bio-Oss and autogenous bone in different ratios in mini pigs.

OBJECTIVES: The objective was to test the hypotheses: (i) no differences in bone-to-implant contact formation, and (ii) no differences between the use of autogenous mandibular or iliac bone grafts, when autogenous bone, Bio-Oss mixed with autogenous bone, or Bio-Oss is used as graft for the maxillary sinus floor augmentation. MATERIAL AND METHODS: Bilateral sinus floor augmentation was performed in 40 mini pigs with: (A) 100% autogenous bone, (B) 75% autogenous bone and 25% Bio-Oss, (C) 50% autogenous bone and 50% Bio-Oss, (D) 25% autogenous bone and 75% Bio-Oss, or (E) 100% Bio-Oss. Autogenous bone was harvested from the iliac crest or the mandible and the graft composition was selected at random and placed concomitant with the implant placement. The animals were euthanized 12 weeks after surgery. Bone-to-implant contact was estimated by stereological methods and summarized as median percentage with 95% confidence interval (CI). Bone-to-implant contact formation was evaluated by fluorochrome labelling and assessed by median odds ratios (OR) with 95% (CI). RESULTS: Median bone-to-implant contact was: (A) 42.9% (95% CI: 32.1-54.5%), (B) 37.8% (95% CI: 27.1-49.9%), (C) 43.9% (95% CI: 32.6-55.9%), (D) 30.2% (95% CI: 21.6-40.3%), and (E) 13.9% (95% CI: 11.4-16.9%). Bone-to-implant contact was significantly higher for A, B, C, D as compared to E (P < 0.0001). Bone-to-implant contact was not significantly influenced by the ratio of Bio-Oss and autogenous bone (P = 0.19) or the origin of the autogenous bone (P = 0.72). Fluorochrome labelling revealed extensive variation in bone-to-implant contact formation over time. The labelling at weeks 2-3 was significantly increased with A compared to E (OR = 8.1 CI: 5.0-13.1, P < 0.0001), whereas E showed a significantly increased labelling at weeks 8-9 compared to A (OR = 0.5 CI: 0.3-0.7, P = 0.0028). CONCLUSIONS: The hypothesis of no differences in bone-to-implant contact between the various treatment modalities was rejected since the bone-to-implant contact was significantly increased with autogenous bone or Bio-Oss mixed with autogenous bone as compared to Bio-Oss. Early bone-to-implant contact formation was more advanced with autogenous bone. No differences between the use of mandibular or iliac bone grafts were observed since the bone-to-implant contact was not significantly influenced by the origin of the bone graft.

Efficiency of bupivacaine versus lidocaine and methylprednisolone versus placebo to reduce postoperative pain and swelling after surgical removal of mandibular third molars: a randomized, double-blinded, crossover clinical trial.

PURPOSE: To compare 4 treatment combinations to reduce postoperative pain and swelling after surgical removal of mandibular third molars. PATIENTS AND METHODS: Patients scheduled for bilateral mandibular third molar removal were randomized to 1 of 4 treatment groups in a double-blinded crossover design: 1) first operation: lidocaine and placebo, second operation: bupivacaine and methylprednisolone; 2) first operation: bupivacaine and methylprednisolone, second operation: lidocaine and placebo; 3) first operation: lidocaine and methylprednisolone, second operation: bupivacaine and placebo; 4) first operation: bupivacaine and placebo, second operation: lidocaine and methylprednisolone. Patient-reported pain and swelling were recorded using visual analog scales 2, 4, 6, 8, and 12 hours after surgery and daily during the first postoperative week. The treatment effects were estimated as contrasts between the average differences within the treatment groups and assessed by stratified t tests. RESULTS: A total of 126 patients (57 women and 69 men; mean age, 25.0 years) were included in the analysis. No significant interactions between local analgesia and methylprednisolone were observed. The administration of bupivacaine resulted in less postoperative pain up to 12 hours after surgery (P < .004) and more postoperative swelling 4 to 12 hours after surgery (P < .001) compared with lidocaine. The administration of methylprednisolone resulted in less postoperative pain 4 to 12 hours and 2 days after surgery (P < .05) and less postoperative swelling 6 and 12 hours and 1 to 3 days after surgery (P < .04) compared with placebo. CONCLUSIONS: Bupivacaine combined with methylprednisolone reduced the postoperative pain and swelling compared with the use of lidocaine and placebo, lidocaine and methylprednisolone, or bupivacaine and placebo.

Diagnostic accuracy of panoramic radiography, stereo-scanography and cone beam CT for assessment of mandibular third molars before surgery.

OBJECTIVE: To compare the diagnostic accuracy of panoramic imaging, stereo-scanography and cone beam computed tomography (CBCT) for assessment of mandibular third molars. MATERIAL AND METHODS: One hundred and twelve patients (147 third molars) underwent radiographic examination by panoramic imaging, stereo-scanography and CBCT. Tooth angulation, root morphology, number of roots and relation to the mandibular canal were assessed. The same variables were assessed intra- and post-operatively and served as reference for the radiographic assessments. The diagnostic accuracy for each variable was compared between the three modalities and accuracy was further expressed as sensitivity and specificity and tested between the modalities for identifying the relation to the mandibular canal. RESULTS: There were no significant differences between the modalities regarding tooth angulation, root morphology and number of roots. However, CBCT was more accurate than stereo-scanography for determining root bending in the bucco-lingual plane (p = 0.02). Moreover, sensitivity for direct contact to the mandibular canal (panoramic imaging: 0.29, stereo-scanography: 0.57, CBCT: 0.67) was higher for CBCT than for panoramic images (p = 0.05) and specificity for no direct contact to the mandibular canal (panoramic imaging: 0.78, stereo-scanography: 0.53, CBCT: 0.68) was higher for panoramic images and CBCT than for scanograms (p < 0.001). CONCLUSION: Panoramic imaging, stereo-scanography and CBCT seem equally valuable for examination of tooth angulation, number and morphology of roots of mandibular third molars. However, CBCT was more accurate for assessment of root bending in the bucco-lingual plane and more accurate than panoramic images to identify direct contact to the mandibular canal.

Maxillary sinus floor augmentation with Bio-Oss or Bio-Oss mixed with autogenous bone as graft: a systematic review.

AIMS: The objective of the present systematic review was to test the hypothesis of no differences in the implant treatment outcome when Bio-Oss or Bio-Oss mixed with autogenous bone is used as graft for the maxillary sinus floor augmentation (MSFA) applying the lateral window technique. MATERIAL AND METHODS: A MEDLINE (PubMed) search in combination with a hand search of relevant journals was conducted by including human studies published in English from January 1, 1990 to June 1, 2010. The search provided 879 titles and 35 studies fulfilled the inclusion criteria. Considerable variation in the included studies prevented meta-analysis from being performed and no long-term study comparing MSFA with the two treatment modalities was identified. Also, the survival of suprastructures after the two augmentation procedures was not compared within the same study. RESULTS: The 1-year implant survival was compared in one study demonstrating no statistically significant difference. The implant survival was 96% with Bio-Oss and 94% with a mixture of 80% Bio-Oss and 20% autogenous mandibular bone. Addition of a limited amount of autogenous bone to Bio-Oss seemed not to increase the amount of new bone formation and bone-to-implant contact compared with Bio-Oss. CONCLUSIONS: Therefore, the hypothesis of no differences between the use of Bio-Oss or Bio-Oss mixed with autogenous bone as graft for MSFA could neither be confirmed nor rejected.

Volumetric changes of the graft after maxillary sinus floor augmentation with Bio-Oss and autogenous bone in different ratios: a radiographic study in minipigs.

OBJECTIVE: The objective of the present study was to learn about the volumetric changes of the graft after maxillary sinus floor augmentation with Bio-Oss and autogenous bone from the iliac crest or the mandible in different ratios in minipigs. MATERIAL AND METHODS: Bilateral maxillary sinus floor augmentation was performed in 40 minipigs with: (A) 100% autogenous bone, (B) 75% autogenous bone and 25% Bio-Oss, (C) 50% autogenous bone and 50% Bio-Oss, (D) 25% autogenous bone and 75% Bio-Oss, and (E) 100% Bio-Oss. The autogenous bone graft was harvested from the iliac crest or the mandible and the graft composition was selected at random and placed concomitant with implant placement. Computed tomographies of the maxillary sinuses were obtained preoperatively, immediately postoperatively, and at euthanasia after 12 weeks. The volumetric changes of the graft were estimated using the Cavalieri principle and expressed as mean percentage with a 95% confidence interval (CI). RESULTS: The mean volume of the graft was reduced by (A) 65% (95% CI: 60-70%), (B) 38% (95% CI: 35-41%), (C) 23% (95% CI: 21-25%), (D) 16% (95% CI: 12-21%), and (E) 6% (95% CI: 4-8%). The volumetric reduction was significantly influenced by the ratio of Bio-Oss and autogenous bone (P<0.001), but not by the origin of the autogenous bone graft (P=0.2). CONCLUSIONS: The volume of autogenous bone grafts from the iliac crest and the mandible is reduced significantly after maxillary sinus floor augmentation in minipigs. The graft volume is better preserved after the addition of Bio-Oss and the volumetric reduction is significantly influenced by the ratio of Bio-Oss and autogenous bone. However, further studies are needed addressing the amount of new bone formation and bone-to-implant contact before the final conclusion can be made about the optimal ratio of Bio-Oss and autogenous bone.

Single-crown restorations supported by short implants (6 mm) compared with standard-length implants (13 mm) in conjunction with maxillary sinus floor augmentation: a randomized, controlled clinical trial.

BACKGROUND: The purpose of the present study was to test the H0-hypothesis of no difference in the clinical and radiographical treatment outcome of single-crown restorations supported by short implants compared with standard length implants in conjunction with maxillary sinus floor augmentation (MSFA) after 1 year of functional implant loading. Forty patients with partial edentulism in the posterior part of the maxilla were randomly allocated to treatment involving single-crown restorations supported by short implants or standard length implants in conjunction with MSFA. Clinical and radiographical evaluation were used to assess survival of suprastructures and implants, peri-implant marginal bone loss (PIMBL), biological, and mechanical complications. RESULTS: Both treatment modalities were characterized by 100% survival of suprastructures and implants after 1 year. Mean PIMBL was 0.60 mm with short implants compared with 0.51 mm with standard length implants after 1 year of functional loading. There were no statistically significant differences in survival of suprastructure and implants, PIMBL, and mechanical complications between the two treatment modalities. However, a higher incidence of biological complications was associated with standard length implants in conjunction with MSFA. CONCLUSION: Within the limitations of the present study, it can be concluded that single-crown restorations supported by short implants seems to be comparable with standard length implants in conjunction with MSFA. However, long-term studies are needed before final conclusions can be provided about the two treatment modalities. TRIAL REGISTRATION: Clinicaltrials.Gov ID: NCT04518020 . Date of registration: August 14, 2020, retrospectively registered.

A clinical and radiographic study of implants placed in autogenous bone grafts covered by either a platelet-rich fibrin membrane or deproteinised bovine bone mineral and a collagen membrane: a pilot randomised controlled clinical trial with a 2-year follow-up.

PURPOSE: To compare the survival and clinical performance of implants placed in sites previously augmented with autogenous bone grafts covered by either a platelet-rich fibrin (PRF) membrane (PRF group) or a standard procedure (gold standard) involving coverage of the autogenous bone graft with deproteinised bovine bone mineral and a resorbable collagen membrane (control group). METHODS: A total of 27 partially edentulous patients (test n = 14, control n = 13) with indication for staged lateral bone block augmentation and dental implant placement were included. Twenty-four months after crown placement (range: 14-32 months), patients were recalled for a final clinical and radiographic follow-up. Outcome measures were implant survival, implant crown survival, clinical parameters of the implant, peri-implant marginal bone level, marginal bone level of adjacent tooth surfaces, biological and technical complications and patient-related outcome measures. RESULTS: Two implants were lost in the control group (85% survival rate); none were lost in the PRF group (100% survival rate). None of the 26 initially placed implant crowns were lost, but one implant and therefore one implant crown were lost after 20 months. Consequently, the definitive implant crown survival was 92% (95% confidence interval (CI): 73-110%) in the control group and 100% in the PRF group. No statistical difference in implant survival rate (p = 0.13) or implant crown survival was seen between the groups (p = 0.28). The mean marginal bone level at the follow-up was 0.26 mm (95% CI: 0.01-0.50 mm) in the PRF group and 0.68 mm (95% CI: 0.41-0.96 mm) in the control group. The difference between the groups was - 0.43 mm (95% CI: - 0.80 to - 0.05 mm, p = 0.03), which was statistically significant (p = 0.03). Both groups demonstrated similar healthy peri-implant soft tissue values at the final follow-up. CONCLUSION: Although the current study is based on a small sample of participants, the findings suggest that the methodology of the PRF and the control group approach can both be used for bone augmentation with a similar outcome. A significant, but clinically irrelevant, higher peri-implant marginal bone level was registered in the PRF group than in the control group. Patients in both groups were highly satisfied with the treatment. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04350749 . Registered 17 April 2020. Retrospectively registered.