Analysis of Alveolar Bone Morphology of the Maxillary Central and Lateral Incisors with Normal Occlusion.

Background and objectives: This study investigated the morphology of the labial and palatal bony wall of the maxillary central and lateral incisors using cone-beam computed tomography (CBCT). The difference between males and females and the measurement between right and left sides were measured. Materials and Methods: Twenty participants, consisting of 11 females and 9 males having normal occlusion, were used for the analysis. The mean age was 21.9 ± 3.0 years. The thickness of the labial bony wall and palatal bony wall, perpendicular to the long axis of the root, were evaluated at 3 and 5 mm apical from the cemento-enamel junction (CEJ) and at the root apex. The available bony wall below the apex of the central and lateral incisors, and the angulation between the long axis of the tested tooth and outer surface of the labial bone were measured. Results: The mean labial bony wall thickness at the 3 and 5 mm apical from the CEJ were 1.1 ± 0.3 mm and 1.0 ± 0.4 mm for central incisors, respectively, as well as 1.2 ± 0.4 mm and 1.0 ± 0.4 mm for lateral incisors, respectively. The mean palatal bony wall thickness at 5 mm from the CEJ was above 2 mm in the central and lateral incisors. The percentage of labial bony wall thickness 2 mm or greater at the root apex in central incisors was higher than in lateral incisors (62.5% vs. 55.0%). The percentage of palatal bony wall thickness ≥2 mm at 3 mm apical from the CEJ in the central incisors was higher than in the lateral incisors (37.5% vs. 15.0%). The results on the left and right sides did not show statistically significant differences, except in the labial and palatal bony wall thickness at 3 mm from the CEJ in the lateral incisor. Generally, no significant differences were seen between males and females, but males had a significantly higher labial bony wall thickness at 3 and 5 mm from the CEJ in the central and lateral incisors when compared with females. Conclusions: This study showed that a majority of the cases of Korean participants had less than 2 mm of labial bony wall thickness at 3 and 5 mm apical from the CEJ at central and lateral incisors, and this should be kept in mind while performing dental practices, including tooth extraction or immediate implantation in anterior regions. Preoperative analysis using CBCT may be beneficial for establishing the treatment plan.

Morphometric and histopathological evaluation of the effect of grape seed proanthocyanidin on alveolar bone loss in experimental diabetes and periodontitis.

OBJECTIVE: Grape seed proanthocyanidine extract (GSPE) is a strong antioxidant derived from the grape seeds (Vitis vinifera, Terral J.F.) and has a polyphenolic structure with a wide range of biological activity. The aim of the present study was to evaluate the effects of GSPE on alveolar bone loss and histopathological changes in rats with diabetes mellitus and ligature-induced periodontitis. MATERIAL AND METHODS: Forty rats were divided into 6 study groups. Control (C, 6 rats) group, periodontitis (P, 6 rats) group, diabetes (D, 6 rats) group, diabetes and periodontitis (D+P, 6 rats) group, diabetes, periodontitis and 100 mg/kg/day GSPE (GSPE-100, 8 rats), and diabetes, periodontitis and 200 mg/kg/day GSPE (GSPE-200, 8 rats) group. Diabetes mellitus was induced by intraperitoneal injection of a single dose of streptozotocin (60 mg/kg). Periodontitis was induced via ligation method. Silk ligatures were placed at the mandibular right first molars. GSPE was administered by oral gavage. After 30 days, all rats were killed. Alveolar bone loss was measured morphometrically via a stereomicroscope. For histopathological analyses, Alizarin red staining, and matrix metalloproteinase (MMP)-8, vascular endothelial growth factor and hypoxia inducible factor (HIF)-1α immunohistochemistry were performed. Tartrate-resistant acid phosphatase-positive osteoclast cells and relative total inflammatory cells were also determined. RESULTS: The highest alveolar bone loss was observed in the D+P group (P < .05). GSP-200 group decreased alveolar bone loss (P < .05). The D+P group had the highest osteoclast counts, but the difference was not significant compared to the P, GSPE-100 and GSPE-200 groups (P > .05). The inflammation in the D+P group was also higher than the other groups (P < .05). The osteoblast numbers increased in the GSPE-100 and GSPE-200 groups compared to the P and D+P groups (P < .05). MMP-8 and HIF-1α levels were highest in the D+P group and GSPE significantly decreased these levels (P < .05). CONCLUSION: Within the limits of this animal study, it can be suggested that GSPE administration may decrease periodontal inflammation and alveolar bone loss via decreasing MMP-8 and HIF-1α levels and increase osteoblastic activity in diabetic rats with experimental periodontitis.

Steatosis caused by experimental periodontitis is reversible after removal of ligature in rats.

BACKGROUND AND OBJECTIVE: Periodontitis may promote harmful systemic effects such as changes in hepatic tissues. The purpose of this study was to investigate whether the steatosis and oxidative stress caused by experimental periodontitis are reversible in the liver. MATERIAL AND METHODS: Twenty-four rats were divided into three groups: control, periodontitis and P20-20 (20 days with experimental periodontitis and 20 days without experimental periodontitis, to verify the reversibility of hepatic injuries). The following parameters were assessed: gingival bleeding index, probing pocket depth, myeloperoxidase activity, alveolar bone loss for periodontal tissues; liver weights, histopathological scores for steatosis, inflammation and necrosis in liver; glutathione, malondialdehyde, total cholesterol and triglyceride concentrations in hepatic tissues; and blood levels of aspartate aminotransferase, alanine aminotransferase, albumin, gamma-glutaryl transferase, total cholesterol and random glucose. RESULTS: Gingival bleeding index, probing pocket depth, myeloperoxidase and alveolar bone loss parameters demonstrated the development of periodontitis. There was a significant reduction in the steatosis score of animals from the P20-20 group when compared with the periodontitis group. P20-20 group presented significantly higher glutathione (11 times) and lower malondialdehyde (nearly 23%), total cholesterol (both in blood and hepatic tissue) and triglyceride concentrations compared with the periodontitis group. For levels of aspartate aminotransferase, alanine aminotransferase, albumin, gamma-glutaryl transferase and random glucose, a significant difference between the groups was not observed. CONCLUSION: Our results demonstrate that the microvesicular steatosis caused by periodontitis in rats is reversible after removal of the ligature, which is associated with the increase in oxidative stress and lipid peroxidation in the liver.

Classification of alveolar bone destruction patterns on maxillary molars by using cone-beam computed tomography.

OBJECTIVE: The defective diagnosis of alveolar structures is one of most serious handicaps when assessing available periodontal treatment options for the prevention of tooth loss. The aim of this research was to classify alveolar bone defects in the maxillary molar region which is a challenging area for dental implant applications. To our knowledge, this is the first study of periodontal bone defect prevalence by using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: In this study, the remaining alveolar bone patterns of 669 maxillary molars of 243 patients with periodontal bone loss were investigated on four aspects and the furcation areas of teeth, and then they were classified into six main groups. Combined periodontal-endodontic lesions (CPELs) were also reported in another category. RESULTS: Following exclusion of 39 (5.8%) teeth with CPEL, the most common group was horizontal bone defects (71.4%) and the least seen group was three-walled vertical bone defects (1.9%) in all alveolar bone sides of teeth. Osseous crater was found at the rate of 6.7% on interdental alveolar bone. Dehiscence and fenestration were detected at rates of 2.7% and 3.3%, respectively. In the assessment of furcation areas, there was no furcation involvement in 61.4% of all teeth and the rate of Grade-II involvements was 26.2%. CONCLUSIONS: The most appropriate treatment option may be decided through accurate imaging of periodontal defect morphology. CBCT can provide comprehensive information about the remaining alveolar bone structures. In this way, the need for dental implant can be prevented in many cases and be replaced with a more conservative approach on the maxillary molar region.

Does Length, Diameter, or Bone Quality Affect Primary and Secondary Stability in Self-Tapping Dental Implants?

PURPOSE: Implant stability is a clinically valuable measurement of the strength of implant anchorage in the bone during placement and in the post-osseointegration period. This study aimed to determine 1) the effect of implant diameter and length and bone quality on measurements of primary and secondary stability (insertion torque [IT] and implant stability quotient [ISQ]), 2) the correlation between IT and primary and secondary ISQ, and 3) differences in ISQ in the post-osseointegration period (secondary stability) compared with immediate post-placement (primary) stability. PATIENTS AND METHODS: In this longitudinal clinical study, titanium self-tapping implants were inserted in edentulous patients. The implants were grouped according to 3 independent variables: length (10 and 11.5 mm), diameter (3.75 and 4.25 mm), and bone quality (Lekholm and Zarb classification) to analyze primary and secondary implant stability (outcome variables). Statistical analyses were performed using the Student t test for paired data, 1-way analysis of variance, and the Tukey procedure for multiple pairwise comparisons. RESULTS: Data were collected on 88 self-tapping implants inserted in 63 partially edentulous patients. IT and implant stability were affected by diameter (3.75-mm implants, 26.5-N/cm IT and 74.0 ISQ; 4.25-mm implants, 33.8-N/cm IT and 77.0 ISQ) and bone type (type 1 + 2, 34.86-N/cm IT and 77.4 ISQ; type 3, 27.09-N/cm IT and 75.6 ISQ; type 4, 20.63-N/cm IT and 70.5 ISQ; P < .01 for all comparisons). Secondary ISQ was affected by diameter only (77.41 for 3.75- vs 75.51 for 4.25-mm implants). IT correlated with primary ISQ (R = 0.56; P < .01), although no clear correlation with secondary stability was found. CONCLUSIONS: IT and primary ISQ in self-tapping implants differed in patients with different bone quality and implant diameter but did not differ between the 2 implant lengths compared in this study. Secondary stability was not substantially affected by any of these factors. Although IT was closely related to primary ISQ, it was unrelated to secondary ISQ. Very high primary ISQ values tended to decrease, whereas intermediate and low values tended to increase, in the transition to secondary stability.

The outcome of oral implants placed in bone with limited bucco-oral dimensions: a 3-year follow-up study.

AIM: The dimension of the alveolar bone reduces significantly after tooth loss. Clinicians consider a 1-2 mm buccal and lingual bone width mandatory around the implant at placement. This prospective study analysed the outcome of implants inserted in jaws with narrow (≤4.5 mm) buccal bone dimensions. MATERIAL AND METHODS: Twenty-eight patients (mean age 63, 89% female) with a narrow alveolar crest (≤4.5 mm in width on CBCT) received 100 implants (3.5 mm) via a two-stage procedure. Intra-oral radiographs were taken at placement, functional loading and after 1, 2 and 3-years of follow-up. Peri-implant bone level alterations were recorded by two calibrated, periodontologists. RESULTS: All implants integrated and the cumulative survival rate after 3 years was 100%. The implants were inserted 0.81 mm ± 0.83 subcrestal. At functional loading the bone was located 0.65 mm ± 0.6 apical of the implant shoulder. During 3 years of loading the amount of annual marginal bone loss was 0.17 ± 0.4, 0.05 ± 0.4 and - 0.06 ± 0.1 mm, respectively. CONCLUSION: Based on these data and within the limitations of this study it became clear that implants, placed in sites with limited dimensions (≤4.5 mm width), showed minimal amounts of marginal bone loss during the first 3 years of functional loading.

Effect of different prosthetic abutments on peri-implant soft tissue. A randomized controlled clinical trial.

PURPOSE: This randomized clinical trial assessed the effect of three different prosthetic abutments (titanium, gold-hue titanium and zirconia) on peri-implant soft tissue 2 years after treatment in partially edentulous subjects. METHODS: Baseline data concerning (1) thickness of the buccal peri-implant soft tissue, (2) soft tissue thickness above the bone crest, (3) depth/length of transmucosal pathway, and (4) periodontal biotype at adjacent teeth were collected. The final sample consisted of 47 subjects (21 males, 26 females) with a total of 97 implants. A two-level (patient, implant) statistical model was applied. RESULTS: At the 2-year clinical observation, recession of the gingival margin was observed only at 13% of implants irrespective of the type of abutment. No significant correlation between periodontal biotype at adjacent teeth and peri-implant biotype was observed. Furthermore, none of the investigated variables at patient level (age, gender, implant type, periodontal biotype) or at implant level (keratinized tissue thickness, probing depth, soft tissue thickness) was identified as a significant predictor of recession. In conclusion, this study pointed out that (1) abutment type was not able to influence peri-implant variables after 2 years, and (2) caution should be used in considering periodontal biotype at patient level as a possible indicator of the future peri-implant biotype.

Consecutive unsplinted implant-supported restorations to replace lost multiple adjacent posterior teeth: A 4-year prospective cohort study.

OBJECTIVE: The aim of this study was to investigate the various events occurring in unsplinted implant restoration in posterior jaws during a period of 4 years. MATERIALS AND METHODS: From August 2008 to April 2009, eight volunteers (three men and five women) who had two or more consecutively missing teeth received 20 implants in posterior maxillae and mandibles. Unsplinted single crowns were delivered to each implant. For the 4-year follow-up periods, patients were enrolled in a maintenance schedule at 1, 3, 6, 12, 24, 36 and 48 months. The data, including a questionnaire, radiography, mobility and probing were recorded on regular check-ups. RESULTS: A total of 20 implants in eight patients were followed up for 48 months, showing a 100% survival rate. Mean marginal bone loss around implants was 0.26 mm. Statistical analysis revealed insignificant correlation between metal-ceramic and zirconia-ceramic crowns and among implant lengths (8.5 mm, 10 mm and 11.5 mm). Mean probing depths were similar or insignificantly different, regardless of the materials used or length of implants. The most frequent complications, in decreasing order, were food impaction (65%) and porcelain chipping (45%), sensitivity (25%), pain (20%) and loose contact (15%). Compared with metal-ceramic crowns, zirconia-ceramic crowns showed more unfavorable cases of porcelain chipping (p=0.017), pain (p=0.007) and loose contact with an adjacent crown (p=0.031). CONCLUSIONS: Within the limits of the sample size, this study showed that unsplinted implant-supported single restorations to replace consecutive posterior missing teeth may function well.

Immediate Implant Placement in a Patient With Osteoporosis Undergoing Bisphosphonate Therapy: 1-Year Preliminary Prospective Study.

The purposes of this preliminary study are to assess the risk of developing bisphosphonate-related osteonecrosis of the jaw (BRONJ) in a patient with osteoporosis using zoledronic acid and to report the results of a 1-year prospective clinical study regarding 5 immediately inserted implants in the anterior mandible. For this comparative prospective study, 24 female patients, aged ≥54 years, were chosen, all with partially edentulous mandibles. Group A consisted of 12 patients with osteoporosis taking zoledronic acid receiving a once-yearly intravenous infusion of zoledronic acid (5 mg). Control group B consisted of 12 other patients without osteoporosis and not taking drugs. In both groups, the remaining teeth were extracted before 120 implants, 3.7-mm wide and 16-mm long, were immediately installed in the interforaminal region of the mandibles. The 1-year implant survival rate was 100%. No apparent necrotic bone was observed among patients receiving zoledronic acid (group A) after implant surgery. Immediate implant osseointegration can be successful in a patient with osteoporosis using bisphosphonates, suggesting the safety of implantology as a treatment modality.

Short implants in maxillary and mandibular rehabilitations: interim results (6 to 42 months) of a prospective study.

The aim of this single-cohort study was to evaluate clinical survival and success of partial rehabilitation supported by reduced-length implants in maxilla and mandible. Data from 53 short implants placed in 41 patients are presented. Before surgery mean residual bone height was 6.21 ± 1.05 mm in the upper jaw and 10.73 ± 1.63 mm in the mandible. None of the implants failed, and the cumulative survival rate was 100% at 1 year after prosthetic loading. Mean peri-implant bone loss was 0.69 ± 0.24 mm for maxillary implants and 0.73 ± 0.23 mm for mandibular implants, and there was no significant difference between the 2 jaws. No complications were recorded. Despite the limitations of this study concerning study design and sample size, short implants may be considered effective in supporting partial rehabilitation in both maxilla and mandible. More well-designed studies with a larger sample size and longer follow-up are needed to validate the use of short implants.

[Evaluation of periodontal health of prosthetic abutments. Pilot study about 100 abutments of crowns and bridges]. / Evaluation de la santé parodontale des piliers de prothèse fixée. Etude pilote autour de 100 piliers de couronnes et de bridges.

BACKGROUND: The confection of a fixed prosthesis finds its indication in response to the patient's aesthetic and/or functional whose requirements are stronger in terms of satisfaction. This involves maintaining the stability of prosthetic reconstructions on a sufficiency long time. To achieve this, the preservation of periodontal health of the prosthetic abutments occupies a special choice. PURPOSE: The aim of this study was to evaluate the periodontal health of fixed prosthesis abutment. MATERIALS AND METHODS: Thirty-nine patients having fixed prosthesis in the mouth for more than one year participated in our study. Ultimately, 38 single crowns and 27 seven bridges based on 100 abutments have been recorded. After an interview, clinical and radiographic examination was performed. It was to assess the level of oral hygiene, the health of the superficial and deep periodontal abutment using OHIS index of Green and Vermilion, periodontal index of Russel and mobility index of Mühlemann. RESULTS: On the 100 abutments examined, gingivitis (14%), gingival recession (13%), bone osteolysis (29%) and mobility (5%) were recorded. In addition, about 60% of patients had inadequate oral hygiene and less than 30% of them had a regular prosthetic maintenance. CONCLUSION: From this study, it appears that complications affecting periodontal prosthetic abutments are essentially bone lysed (29%), gingivitis (14%) and gingival recessions (13%).

Horizontal bone augmentation by means of guided bone regeneration.

The development of bone augmentation procedures has allowed placement of dental implants into jaw bone areas lacking an amount of bone sufficient for standard implant placement. Thus, the indications for implants have broadened to include jaw regions with bone defects and those with a bone anatomy that is unfavorable for implant anchorage. Of the different techniques, the best documented and the most widely used method to augment bone in localized alveolar defects is guided bone regeneration. A large body of evidence has demonstrated the successful use of guided bone regeneration to regenerate missing bone at implant sites with insufficient bone volume and the long-term success of implants placed simultaneously with, or after, guided bone regeneration. However, the influence of guided bone regeneration on implant survival and success rates, and the long-term stability of the augmented bone, remain unknown. Many of the materials and techniques currently available for bone regeneration of alveolar ridge defects were developed many years ago. Recently, various new materials and techniques have been introduced. Many of them have, however, not been sufficiently documented in clinical studies. The aim of this review was to present the scientific basis of guided bone regeneration and the accepted clinical procedures. A classification of bone defects has been presented, aiming at simplifying the decision-making process regarding the choice of strategy for bone augmentation. Finally, an outlook into actual research and the possible future options related to bone augmentation has been provided.

Assessment of high-sensitivity C-reactive protein and lipid levels in healthy adults and patients with coronary artery disease, with and without periodontitis--a cross-sectional study.

BACKGROUND AND OBJECTIVE: Various epidemiological studies have implied that local infection may increase the levels of systemic inflammatory mediators and lipid mediators, thereby promoting atherosclerosis. The aim of this study was to assess high-sensitivity C-reactive protein (HsCRP) and lipid levels in healthy adults and patients with coronary artery disease (CAD), with and without periodontitis. MATERIAL AND METHODS: A total of 100 subjects were included in the study and categorized into four groups of 25 subjects each, as follows: subjects with chronic periodontitis with angiographically proven CAD; nonperiodontitis subjects with angiographically proven CAD; otherwise healthy subjects with only chronic periodontitis; and systemically and orally healthy individuals. The periodontal parameters measured included plaque index, gingival index, probing pocket depth, clinical attachment level and marginal alveolar bone loss (which was recorded radiographically). Serum samples were collected for estimation of HsCRP, low-density lipoprotein (LDL), high-density lipoprotein (HDL) and triglycerides (TGs). RESULTS: The serum HsCRP levels in subjects with either CAD or chronic periodontitis were elevated two-fold compared with those of healthy individuals, whereas in subjects with both diseases (CAD plus chronic periodontitis) the levels were elevated three-fold. The serum LDL level was higher, and the serum HDL level was lower, in all the test groups compared with the healthy group. No significant difference among the groups was detected in the TG levels. CONCLUSION: A persistent infection, such as chronic periodontitis, may influence changes in the systemic levels of HsCRP, LDL and HDL, which potentially have an impact on inflammation-associated atherosclerotic processes, such as CAD.

Differential expression of Toll-like receptor 4 in healthy and diseased human gingiva.

BACKGROUND AND OBJECTIVE: Lipopolysaccharide (LPS)-mediated signaling in host cells involves Toll-like receptor 4 (TLR4) accessory molecules, including LPS-binding protein (LBP), cluster of differentiation 14 (CD14) and lymphocyte antigen 96 (MD-2). However, expression of these innate defense molecules in various compartments of the human periodontium is unclear. The aim of this study was to investigate the expression profile of TLR4 in human gingiva. MATERIAL AND METHODS: Human gingival biopsies were collected from healthy gingival or chronic periodontitis tissue. Primary gingival keratinocytes and fibroblasts were cultured. Immunohistochemical analysis for TLR4 was performed. Transcripts of TLR4, MD-2, CD14 and LBP, and their protein products, were examined using RT-PCR, immunoprecipitation and immunoblotting. The interactions between these molecules in keratinocytes and fibroblasts were investigated by co-immunoprecipitation. RESULTS: TLR4 immunoreactivity was found in healthy gingival epithelium and periodontitis tissue, and appeared to be lower in junctional epithelium ( p ≤ 0.01). Fibroblasts and inflammatory cells stained more strongly for TLR4 in diseased periodontal tissues (p < 0.001). Three TLR4 splicing variants, two MD-2 splicing variants and one CD14 mRNA were expressed by gingival keratinocytes and fibroblasts. Expression of TLR4, CD14 and MD-2 proteins was detected in keratinocytes and fibroblasts in vitro. TLR4 protein from gingival keratinocytes and fibroblasts could be co-immunoprecipitated with CD14 or MD-2, suggesting an association between the related molecules in vivo. LBP transcript was detected in gingival biopsies, but not in primary cultures of gingival keratinocytes or fibroblasts. CONCLUSION: TLR4, CD14 and MD-2, but not LBP, are expressed in human gingival keratinocytes and fibroblasts. The TLR4 expression level in the junctional epithelium appeared to be lowest within the periodontal epithelial barrier.

Incidence of peri-implant mucositis and peri-implantitis in edentulous patients with an implant-retained mandibular overdenture during a 10-year follow-up period.

OBJECTIVES: The aim of this sub-analysis of two prospective studies was to assess the incidence of peri-implant mucositis and peri-implantitis in fully edentulous patients with an implant-retained mandibular overdenture during a 10-year follow-up period. MATERIAL AND METHODS: One hundred and fifty edentulous patients with two endosseous implants to support a mandibular overdenture were available from two prospective studies. Clinical and radiographic parameters were assessed at 5 and 10 years of functional loading. Incidence of peri-implant mucositis and peri-implantitis were calculated at implant level and patient level following the Consensus of the Seventh European Workshop on Periodontology on peri-implant diseases. RESULTS: Incidence of peri-implant mucositis at patient level was 51.9% after 5 years of evaluation and 57.0% after 10 years. Incidence of peri-implantitis at patient level was 16.9% after 5 years of evaluation and 29.7% after 10 years. CONCLUSION: Peri-implant mucositis and peri-implantitis do occur in totally edentulous patients and incidence numbers are high.

Long-term analysis of osseointegrated implants in non-smoker patients with a previous history of periodontitis.

AIM: To evaluate long-term clinical and radiographic parameters of osseointegrated implants in non-smoker patients with a previous history of chronic periodontitis. MATERIALS AND METHODS: Fifty-four screw-type implants with a moderately roughened surface and internal hexagonal implant-abutment connection were placed according to a two-phase protocol and 40 reference teeth were analysed at baseline, and after 5 and 10 years. Pocket probing depth (PPD), clinical attachment level (CAL) and bleeding on probing were analysed 6x/tooth in all teeth, implants and reference teeth. Radiographic peri-implant bone level was measured on the mesial and distal surfaces. The prevalence of peri-implantitis and the survival rate of the implants were assessed at the patient and implant levels. Data were analysed using descriptive statistics, Mann-Whitney U-test, and Wald Z-test, at α = 5%. RESULTS: In implants, the CAL at 5 years was 0.3 mm higher, and at 10 years 1.2 mm higher in comparison to baseline. The corresponding data for the reference teeth were 0 mm and 0.5 mm respectively. Multilevel testing showed statistical difference for PPD between implants and teeth over time. After 10 years, the mean mesial bone loss was 0.63 ± 0.26 mm, and the mean distal bone loss was 0.56 ± 0.25. The survival rates were 100% and 92.3% for the implants in the mandible and the implants in the maxilla respectively. CONCLUSIONS: Screw-type implants with internal hexagon placed in patients with a previous history of periodontitis attending a regular maintenance programme demonstrated stable clinical and radiographic results after 5 and 10 years.

Implant- and patient-centred outcomes of guided surgery, a 1-year follow-up: An RCT comparing guided surgery with conventional implant placement.

AIM: To assess, in a randomized study, the implant (clinical and radiological) and patient outcomes of guided implant placement at 1-year follow-up, compared to conventional implant treatment. MATERIAL AND METHODS: A total of 314 were placed in 59 patients, randomly assigned to one of the treatment groups. Radiographic and clinical parameters were recorded at the time of implant placement, prosthesis instalment (baseline) and at 1-year follow-up. Patient satisfaction was measured with the oral health-related quality of life instrument (OHIP-49). RESULTS: No implants were lost. The mean marginal bone loss after the first year of loading was 0.04 mm (SD 0.34) for the guided surgery and 0.01 mm (SD 0.38) for the control groups. In the guided surgery groups, the mean number of surfaces with BOP and plaque at 1-year follow-up was 1.41 (SD 1.25) and 1.10 (SD 1.22), for the control groups this was, respectively, 1.37 (SD 1.25) and 1.77 (SD 1.64). The mean pocket probing depth was 2.81 mm (SD 1.1) for the guided, and 2.50 mm (SD 0.94) for the control groups. For all treatment groups, a significant improvement in quality of life was observed at 1-year follow-up (p ≤ 0.01), no differences between groups were observed. CONCLUSION: Within the limitations of this study, no difference could be found at 1-year follow-up between the implant and patient outcome variables of guided or conventional implant treatment.

The accuracy of cone-beam computed tomography in assessing maxillary molar furcation involvement.

AIM: The aim of this study was to investigate the accuracy of cone-beam computed tomography (CBCT) in assessing maxillary molar furcation involvement (FI). MATERIALS AND METHODS: Fifteen patients with generalized chronic periodontitis after initial therapy were recruited. CBCT was performed in maxillary molars with probing pocket depths of ≥6 mm and advanced FI, and CBCT images were analysed. Furcation surgery was performed in 20 maxillary molars. Lastly, intra-surgical FI assessments were compared with CBCT-based data. RESULTS: Intra-surgical findings confirmed 82.4% of the CBCT data, with a weighted kappa of 0.917. The agreement between both assessments was the highest in buccal furcation entrances, followed by distopalatal and mesiopalatal furcation entrances. Of the four parameters tested of detailed root anatomy and furcation morphology, the mean length of the root trunk and the width of the furcation entrance revealed by CBCT were consistent with their respective intra-surgical values (p > 0.05). Horizontal bone loss and vertical bone loss were underestimated by CBCT relative to their respective intra-surgical classifications (p ≤ 0.05). CONCLUSIONS: Cone-beam computed tomography images demonstrate a high accuracy in assessing the loss of periodontal tissue of the FI and root morphologies in maxillary molars.

Implant treatment choice after extraction of a vertically fractured tooth. A proposal for a clinical classification of bony defects based on a systematic review of literature.

OBJECTIVES: The objectives of this study were to propose a classification for the bone defects resulting after extraction of a vertically fractured tooth and to review the existing literature about the treatment of such kind of defects by means of dental implants in combination with regenerative procedures. MATERIALS AND METHODS: An electronic search was performed on biomedical databases using a combination of appropriated search terms combined through the use of Boolean operators. All articles concerning the treatment of peri-implant bone dehiscences and fenestrations through guided bone regeneration (GBR) with at least 6 months follow-up were eligible. Outcomes data extracted from the selected articles were summarized using descriptive tables. A classification of the bone defects associated with vertical root fracture (VRF) was also proposed. RESULTS: A total of 33 articles were included in the review. Twenty-three articles (814 implants) were about bone dehiscence treatment, ten articles presented the treatment of fenestrations, and ten (429 implants) adopted vertical bone augmentation. The percentage of bone filling was variable among different procedures and defect classification. The use of resorbable membrane was associated with better outcomes than the use of non-resorbable ones. CONCLUSIONS: Guided bone regeneration for the management of bone defects in the presence of a VRF of the extracted tooth is a viable treatment option. The assessment of bone defect geometry prior to a tooth extraction could be clinically relevant for evaluating the feasibility and the success of immediate implant placement as well as the need of GBR.

Piezoelectric vs. conventional drilling in implant site preparation: pilot controlled randomized clinical trial with crossover design.

OBJECTIVE: To compare implant stability throughout osseointegration, peri-implant marginal bone loss, and success rates of implants placed with conventional and mixed drilling/piezoelectric osteotomy. MATERIALS AND METHODS: A pilot randomized-controlled trial was performed on 15 patients. Each patient received two implants in the mandibular molar region. All sites were prepared with conventionally up to the 2.8 mm wide drill. Osteotomies were randomly finalized with a 3 mm diameter drill (control group) or with two consecutive ultrasonic tips (2.8 mm and 3 mm wide, respectively) (test group). Resonance frequency analysis measurements were taken at implant placement and after 1, 3, 8, and 12 weeks. Peri-implant marginal bone loss 12 months after loading was calculated using periapical radiographs. Wilcoxon test for related samples was used to study differences in implant stability and in peri-implant marginal bone loss between the two groups. RESULTS: Twenty-nine of 30 implants osseointegrated successfully (one failure in the control group). Stability was significantly higher in the test group at the 8th week assessment; differences were non-significant at all other time-points. Longitudinally, differences were observed between the patterns of implant stability changes: in the test group stability increased more progressively, while in the control group an abrupt change occurred between the 8th and 12th weeks assessments. No difference was found in peri-implant marginal bone loss between the groups. All 29 implants were functionally successful at the 15-month visit. CONCLUSIONS: Within the limit of this pilot study (small sample size, short follow-up), data suggested that implant stability might develop slightly faster when implant site osteotomy is performed with a mixed drilling/ultrasonic technique.