Alteration of Keratinized Mucosa Dimensions in the Early Healing Period after Implant Placement: A 6-month Prospective Study.

PURPOSE: This study aimed to assess the alteration in keratinized mucosa (KM) dimensions in the early healing period after implant placement, and the influence of variables obtained during implant surgery on KM alteration. MATERIALS AND METHODS: Study participants were consecutively recruited from patients who had received implants following a non-submerged surgical protocol. The implant had to be installed in the extraction socket that had healed for more than 6 months without any soft or hard tissue augmentation. Keratinized mucosa width (KMW), keratinized mucosa thickness (KMT), soft tissue level (STL), and probing pocket depth (PPD) were measured at implant placement and 3 and 6 months after implant surgery. The influence of variables obtained during implant surgery on the 6-month KMW alteration was assessed. RESULTS: A total of 66 implants in 55 patients who completed the follow-up examination after 6 months were included in this study. KMW, KMT, and STL significantly decreased at 3- and 6-months examination by 0.7-1.2 mm. KMW was reduced by 24.6%. Mesial PPD significantly increased between the 3- and 6-months follow-up. In the multivariate generalized estimating estimations analysis, the implant diameter negatively influenced the 6-month KMW alteration, but the KMW at implant surgery positively influenced the 6-month KMW alteration. CONCLUSIONS: The KMW decreased significantly at 3 and 6 months after implant placement. If the initial KMW was wider, the KMW was reduced more at 6 months after implant placement. Therefore, it is important to carefully monitor KMW alterations during the early healing period to ensure optimal esthetics and peri-implant tissue health.

Pocket closure and residual pockets after non-surgical periodontal therapy: A systematic review and meta-analysis.

AIM: To analyse the efficacy of non-surgical therapy (NST) in terms of pocket closure (PC) and changes in percentage and number of pockets. MATERIALS AND METHODS: Three databases (PubMed, EMBASE, and Scopus) were searched up to January 2020. Prospective studies with a minimum follow-up of 12 months and presenting data in terms of PC or number or percentage of pocket depths (PDs) before and after NST on systemically healthy patients were included. Random-effect meta-analyses were performed. RESULTS: After screening 4610 titles and abstracts, 27 studies were included. Of these, 63.9% of PC was reported by one study. The percentage of PDs ≤3 mm changed from 39.06% to 64.11% with a weighted mean difference (WMD) of 26.14% (p < .001). This accounted for a relative increase of healthy sites of 64.13%. The mean percentage of PD ≥5 mm was 28.23% and 11.71% before and after treatment, respectively, with a WMD of 15.50% (p < .001). The WMD in the number of PDs ≥5 mm before and after treatment was 24.42 (p = .036). The mean number of residual PPD ≥5 after NST was 14.13. CONCLUSIONS: NST is able to eradicate the majority of the pockets. However, residual pockets after NST may remain and should be considered cautiously for further treatment planning.

Chemical cleansing as an adjunct to subgingival instrumentation with ultrasonic and hand devices in deep periodontal pockets: a randomized controlled study.

PURPOSE: The aim of this randomized clinical trial was to assess whether chemical cleansing using a sulfonic/sulfuric acid gel solution (HBX) as an adjunct to scaling and root planing (SRP) resulted in a decrease in residual plaque and calculus in deep periodontal pockets compared to SRP alone. METHODS: Fifty-six patients with 56 hopeless posterior teeth, scheduled for extraction due to severe periodontitis, were enrolled in this study. Each tooth was randomly assigned to 1 of the 2 experimental procedures. The test teeth were subjected to the irrigation of the subgingival area with HBX for 2 minutes, followed by SRP with hand and ultrasonic instruments for 14 minutes, and then extracted. The control teeth received only mechanical instrumentation before extraction. Residual biofilm was evaluated on photographs and measured as total area and percentage of root surface covered by remaining plaque (RP) or calculus (RC) after treatment. RESULTS: The initial pocket depth (PD) and total subgingival root surface area were similar between the 2 treatment groups. After treatment, the total subgingival root area covered by RP and RC was statistically significantly larger (P<0.001) in the control group than in the test group. The test teeth showed a lower percentage of RP, but a higher percentage of RC than the control teeth (both P<0.001). Complete calculus removal was achieved in 42% of the control teeth surfaces and in 25% of the test teeth surfaces for a PD of 4 mm. CONCLUSIONS: The additional chemical cleansing with HBX resulted in a statistically significant improvement in bacterial plaque removal during SRP of deep pockets, but it was not effective in reducing calculus deposits.

Prevalence and risk indicators of peri-implantitis in Korean patients with a history of periodontal disease: a cross-sectional study.

PURPOSE: The aim of this study was to analyze the prevalence and risk indicators of peri-implantitis in Korean patients with history of periodontal disease. METHODS: A total of 444 patients with 1,485 implants were selected from patients who had been treated at the Department of Periodontology, Chonbuk National University Dental Hospital between July 2014 and June 2015. A group with a history of peri-implantitis (HP) (370 patients with 1,189 implants) and a group with a current peri-implantitis (CP) (318 patients with 1,004 implants) were created based on the radiographic and clinical assessments of implants. The prevalence of peri-implantitis was calculated at both the patient and implant levels. The influence of risk variables on the occurrence of peri-implantitis was analyzed using generalized estimating equations analysis. RESULTS: The prevalence of peri-implantitis in the HP and CP groups ranged from 6.7% to 19.7%. The cumulative peri-implantitis rate in the HP group estimated with the Kaplan-Meier method was higher than that in the CP group over the follow-up period. Among the patient-related risk variables, supportive periodontal therapy (SPT) was the only significant risk indicator for the occurrence of peri-implantitis in both groups. In the analysis of implant-related variables, implants supporting fixed dental prosthesis (FDP) and implants with subjective discomfort were associated with a higher prevalence of peri-implantitis than single implants and implants without subjective discomfort in the HP group. The presence of subjective discomfort was the only significant implant-related variable predictive of peri-implantitis in the CP group. CONCLUSIONS: Within the limitations of this study, the prevalence of peri-implantitis in Korean patients with a history of periodontal disease was similar to that reported in other population samples. Regular SPT was important for preventing peri-implantitis. Single implants were found to be less susceptible to peri-implantitis than those supporting FDP. Patients' subjective discomfort was found to be a strong risk indicator for peri-implantitis.

Alterations of papilla dimensions after orthodontic closure of the maxillary midline diastema: a retrospective longitudinal study.

PURPOSE: The aim of this study was to evaluate alterations of papilla dimensions after orthodontic closure of the diastema between maxillary central incisors. METHODS: Sixty patients who had a visible diastema between maxillary central incisors that had been closed by orthodontic approximation were selected for this study. Various papilla dimensions were assessed on clinical photographs and study models before the orthodontic treatment and at the follow-up examination after closure of the diastema. Influences of the variables assessed before orthodontic treatment on the alterations of papilla height (PH) and papilla base thickness (PBT) were evaluated by univariate regression analysis. To analyze potential influences of the 3-dimensional papilla dimensions before orthodontic treatment on the alterations of PH and PBT, a multiple regression model was formulated including the 3-dimensional papilla dimensions as predictor variables. RESULTS: On average, PH decreased by 0.80 mm and PBT increased after orthodontic closure of the diastema (P<0.01). Univariate regression analysis revealed that the PH (P=0.002) and PBT (P=0.047) before orthodontic treatment influenced the alteration of PH. With respect to the alteration of PBT, the diastema width (P=0.045) and PBT (P=0.000) were found to be influential factors. PBT before the orthodontic treatment significantly influenced the alteration of PBT in the multiple regression model. CONCLUSIONS: PH decreased but PBT increased after orthodontic closure of the diastema. The papilla dimensions before orthodontic treatment influenced the alterations of PH and PBT after closure of the diastema. The PBT increased more when the diastema width before the orthodontic treatment was larger.

Food Impaction and Periodontal/Peri-Implant Tissue Conditions in Relation to the Embrasure Dimensions Between Implant-Supported Fixed Dental Prostheses and Adjacent Teeth: A Cross-Sectional Study.

BACKGROUND: Food impaction and periodontal/peri-implant tissue conditions were evaluated in relation to the embrasure dimensions between implant-supported fixed dental prostheses (FDPs) and adjacent teeth. METHODS: A total of 215 embrasures of 150 FDPs in 100 patients (55 males and 45 females, aged 27 to 83 years; mean age: 56 years) were included in the study. Clinical assessments of the periodontal/peri-implant mucosal conditions, radiographic assessments of embrasure dimensions, and overall patient satisfaction were used as explanatory variables for the food impaction and periodontal/peri-implant tissue conditions adjacent to implant-supported FDPs in the generalized estimating equation (GEE) analysis. RESULTS: Food impaction was reported in 96 (44.7%) of 215 embrasures between implant-supported FDPs and adjacent teeth. Food impaction was reported more frequently in the embrasures with proximal contact loss than in those with tight contact (P = 0.009). Overall patient satisfaction was influenced negatively by food impaction in the proximal embrasures (P = 0.01). Among embrasure dimensions, only the embrasure surface area (ESA) significantly influenced food impaction (P = 0.03). Significant influences of various embrasure dimensions on the periodontal/peri-implant mucosal conditions and bone level at the implant were found in the univariate and multivariate GEE analyses. CONCLUSIONS: Food impaction between implant-supported FDPs and adjacent teeth occurred more frequently when proximal contact was lost and ESA increased. Food impaction negatively affected overall patient satisfaction. Embrasure dimensions influenced the periodontal/peri-implant mucosal conditions and bone level at the implant.

Analysis of proximal contact loss between implant-supported fixed dental prostheses and adjacent teeth in relation to influential factors and effects. A cross-sectional study.

OBJECTIVES: The aim was to analyze influential factors and effects of proximal contact loss between implant-supported fixed dental prostheses (FDP) and adjacent teeth. MATERIAL AND METHODS: Ninety-four subjects treated with 135 FDPs supported by 188 implants were included. Degree of proximal contact tightness, food impaction, and periodontal/peri-implant tissue conditions were assessed in 191 proximal embrasures between implant-supported FDPs and adjacent teeth. Potential factors influencing proximal contact loss were estimated with the generalized estimation equation (GEE) procedure. RESULTS: Thirty-four percent of the proximal embrasures between implant-supported FDPs and teeth lost a proximal contact. The proximal contact loss rate continuously increased over the follow-up periods. A longer follow-up period, splinted implants, and mesial aspect of proximal contact were significant factors influencing the proximal contact loss in the univariate GEE analysis, whereas a longer follow-up period was the only significant factor in the multivariate GEE analysis. Food impaction was more frequently reported in the proximal contact loss group than the proximal contact group (odds ratio: 2.2). However, the proximal contact loss did not appear to affect the periodontal/peri-implant tissue conditions. CONCLUSIONS: Proximal contact loss between implant-supported FDPs and teeth occurred frequently and increased continuously over the follow-up period. The proximal contact loss significantly affected food impaction, but not the periodontal/peri-implant tissue conditions. Proximal contact loss should be carefully monitored during follow-up examinations in relation to food impaction.

Soft tissue topography and dimensions lateral to single implant-supported restorations. a cross-sectional study.

OBJECTIVES: The aim was to evaluate potential relationships between the implant position relative to adjacent teeth and dimensions and topography of the papillae lateral to implant-supported single-tooth restorations. MATERIAL AND METHODS: A total of 32 subjects with a single implant-supported restoration in the esthetic zone of the maxilla were consecutively selected for the study. Soft and hard tissues at the proximal sites of the restoration were evaluated by the use of clinical, photographic, diagnostic cast, and radiographic assessments. A questionnaire was used for assessment of the patients' satisfaction with the esthetic outcome of the restorations. Potential factors influencing the papilla level and the presence of a complete papilla fill were investigated with generalized estimation equations (GEE) analysis. RESULTS: The bone level at the adjacent tooth significantly influenced the papilla level (P < 0.001). The distance between the contact point and the bone level at the adjacent tooth was significantly shorter for "complete" (4.3 mm) papillae than that for "deficient" papillae (5.7 mm) (P < 0.001). The GEE logistic model revealed that the chance of a complete papilla fill improved with increased facio-lingual thickness of the papilla (P = 0.004) and decreased distance between the contact point and the bone level at the tooth (P = 0.004). The self-reported satisfaction with the esthetic appearance of the implant-born restoration was not significantly different between patients with "complete" and "deficient" papillae. CONCLUSION: The probability of a complete papilla fill was significantly affected by the facio-lingual dimension of the papilla base and the distance between the contact point between the crowns and the bone level at the tooth.

Longitudinal changes in tooth/single-implant relationship and bone topography: an 8-year retrospective analysis.

PURPOSE: To evaluate longitudinal changes in tooth/implant relationship and bone topography at single implants with a microthreaded, conical marginal portion (Astra Tech ST® implants, Astra Tech AB, Mölndal, Sweden). MATERIAL AND METHODS: Thirty-one subjects with single implant-supported restorations in the esthetic zone were included. Radiographs obtained at crown installation and 1, 5, and 8 years of follow-up were analyzed with regard to changes in (1) bone level at the implant and adjacent teeth and (2) vertical position of adjacent teeth relative to the single implant. RESULTS: The mean marginal bone loss amounted to 0.1 mm at both implants and adjacent teeth during the 8 years of follow-up. Regression analysis failed to identify significant explanatory factors for observed variance in bone level change at the adjacent tooth surfaces. Vertical change in position of the teeth relative to the implants was more frequent and significantly greater in incisor compared with premolar tooth region but not associated with gender or age. CONCLUSIONS: The marginal bone level at teeth adjacent to single implants with a microthreaded conical marginal part was not influenced by horizontal and vertical tooth-implant distances. Continuous eruption of adjacent teeth may result in infraocclusal positioning of a single-implant restoration.

Analysis of the embrasure dimensions between maxillary central incisors in relation to the topography of the interdental papilla.

PURPOSE: To analyze the dimensions of the embrasure space between the maxillary central incisors as potential factors influencing interdental papilla fill and height. METHODS: The embrasure dimensions between the maxillary central incisors of 100 subjects (40 females/60 males) were assessed with clinical, study model, and radiographic examinations. Variables of the complete and deficient papilla fill groups were compared. Multiple regression analyses were performed to investigate potential influence of the distance between the contact point and bone crest (CP_BC), horizontal interdental distance (HID), and facio-lingual thickness (FLT) at the papilla base on complete/deficient papilla fill and papilla height (PH). RESULTS: CP_BC was the only variable that showed a significant difference between the complete and deficient papilla groups (P<0.05). When the CP_BC was less than 5 mm, the embrasure spaces between the maxillary central incisors were completely filled with interdental papilla. Multiple regression analyses revealed that a significant predictor for complete/deficient papilla fill was CP_BC, and significant predictors for PH were CP_BC and HID (P<0.05). CONCLUSIONS: The chances of complete papilla fill increased as CP_BC decreased, while PH increased as CP_BC and HID increased. However, the FLT of the papilla base did not appear to affect papilla fill or PH. From an esthetic perspective, CP_BC as well as HID should be considered as factors influencing the topography of interdental papilla.

Peri-implant soft tissue and bone crest alterations at fixed dental prostheses: a 3-year prospective study.

OBJECTIVES: The aim of this 3-year prospective study involving patients receiving implant-supported fixed dental prostheses (FDPs) was to longitudinally evaluate soft and hard tissue alterations from the time of implant placement. MATERIAL AND METHODS: Sixteen subjects with 18 implant-supported FDPs on 43 implants were included in the study. Peri-implant soft and hard tissue assessments were performed at implant placement, 2, 6, 12, 24 and 36 months. Variables describing the peri-implant soft tissue conditions and topography were assessed by clinical, photographic and study model assessments. Variables of implant position and bone topography were measured in radiographs taken at each examination interval. Multilevel regression models were formulated to identify factors of significance for proximal bone crest alterations and proximal soft tissue height. RESULTS: During the first 6 months after the one-stage implant placement surgery, the soft tissue margin receded about 0.6 mm at facial implant sites, while a mean increase was observed at tooth-facing proximal sites (1.1 mm) and no change at inter-implant sites. Loss in proximal bone crest height was more pronounced at inter-implant than tooth-implant units at 6 months (0.6 vs. 0.1 mm). Between 6 and 36 months, no further significant soft or hard tissue changes were observed. Multilevel regression analysis revealed that the proximal bone crest level significantly influenced the proximal soft tissue height assessed from the implant/abutment level. Significant predictors for loss in proximal bone crest level over the 3 years were horizontal inter-unit distance, type of proximal unit (tooth/implant or inter-implant) and peri-implant bone-level change. CONCLUSIONS: Soft and hard tissue changes around implant-supported FDPs took place primarily during the first 6 months after the one-stage implant installation surgery. The pattern of tissue alterations during the follow-up differed between tooth-implant and inter-implant proximal sites.

Bone alterations at implant-supported FDPs in relation to inter-unit distances: a 5-year radiographic study.

OBJECTIVES: The aim of this 5-year study was to longitudinally evaluate bone alterations around implants with a conical implant-abutment interface in relation to implant-tooth and inter-implant distances. MATERIAL AND METHODS: The patient sample comprised 43 partially dentate patients with a total of 48 implant-supported fixed dental prostheses (FDPs) supported by 130 Astra Tech implants. Following FDP placement (baseline), the patients were enrolled in an individually designed supportive care program. Radiographic examinations were performed at the time of FDP installation, 1 and 5 years of follow-up. Variables regarding implant position and proximal bone topography at tooth/implant units (n=36) and implant/implant units (n=67) were assessed with the use of a software program after scanning of the radiographs. RESULTS: At tooth/implant units, the mean 5-year marginal bone loss at the tooth, the implant and the mid-proximal bone crest was 0.1, 0.4 and 0.2 mm, respectively. The mean longitudinal bone loss at the implant/implant units was 0.5 mm at the implants and 0.3 mm mid-proximally. Multilevel regression analysis revealed that at implant/implant units, the change in the bone-to-implant contact level was a significant predictor with regard to the 5-year mid-proximal bone-level change, whereas the horizontal inter-unit distance showed a borderline significance (P=0.052). At tooth/implant units, no statistically significant associations were identified. CONCLUSIONS: The results of this 5-year study revealed differences between inter-implant and tooth-implant proximal areas with regard to bone crest alterations and associated factors.