Marginal Bone Loss Research Articles

The Effect of Keratinized Mucosa on Peri-Implant Health and Patient-Reported Outcome Measures: A Systematic Review and Meta-Analysis

Objectives: The aim of this systematic review was to analyze the effect of keratinized mucosa (KM) on different peri-implant health-related parameters and on patient-reported outcome measures (PROMs). Material and methods: Randomized controlled trials, cohort, cross-sectional and case–control human studies with a follow-up period of at least 6 months comparing two groups of patients with presence or absence of KM, or with KM < 2 mm or ≥2 mm were included. Primary outcomes were implant failures, PROMs and BoP (BoP/mBI). Additional outcomes were PPD, plaque accumulation (mPI/PI), gingival inflammation (GI/mGI), marginal bone loss (MBL), soft tissue recession (REC) and biological complications. Results: Fifteen studies were included (one RCT, two cohort prospective and twelve cross-sectional). Meta-analysis was performed for cross-sectional studies. Implant failure and complications were not presented as outcome measures, and five studies analyzed PROMs. Results from the meta-analysis reported no evidence of any statistical significant difference between groups in PPD, BoP and MBL, while a statistical significant difference in GI/BI, PI and REC was present in favor of the group with KW ≥ 2 mm. More biological complications were present in the group with no KM/KM < 2 mm but few cases were present to draw any conclusions. Although a meta-analysis could not be performed, a consistent trend toward the worst pain/discomfort in KM < 2 mm was observed. Conclusions: No clear evidence was found supporting the role of KM in peri-implant health and PROMs, even if more plaque and marginal inflammation were present in the KM < 2 mm group. Clinical relevance: KM could have a role in patients with erratic maintenance and patient comfort.

Comparative evidence of different surgical techniques for the management of vertical alveolar ridge defects in terms of complications and efficacy: A systematic review and network meta-analysis.

To systematically appraise the available evidence on vertical ridge augmentation (VRA) techniques and estimate a treatment-based ranking on the incidence of complications as well as their clinical effectiveness. Searches were conducted in six databases to identify randomized clinical trials comparing VRA techniques up to November 2022. The incidence of complications (primary) and of early, major, surgical and intra-operative complications, vertical bone gain (VBG), marginal bone loss, need for additional grafting, implant success/survival, and patient-reported outcome measures (secondary) were chosen as outcomes. Direct and indirect effects and treatment ranking were estimated using Bayesian pair-wise and network meta-analysis (NMA) models. Thirty-two trials (761 participants and 943 defects) were included. Five NMA models involving nine treatment groups were created: onlay, inlay, dense-polytetrafluoroethylene, expanded-polytetrafluoroethylene, titanium, resorbable membranes, distraction osteogenesis, tissue expansion and short implants. Compared with short implants, statistically significant higher odds ratios of healing complications were confirmed for all groups except those with resorbable membranes (odds ratio 5.4, 95% credible interval 0.92-29.14). The latter group, however, ranked last in clinical VBG. VRA techniques achieving greater VBG are also associated with higher incidence of healing complications. Guided bone regeneration techniques using non-resorbable membranes yield the most favourable results in relation to VBG and complications.

Maxillary sinus membrane elevation and coagulum compared with maxillary sinus floor augmentation and a composite graft: A 1-year single-blinded randomized controlled trial.

The aim was to evaluate the 1-year implant outcome and patient-related outcome measures (PROMs) after maxillary sinus membrane elevation and coagulum (test) compared with maxillary sinus floor augmentation and a 1:1 ratio of autogenous bone graft from the buccal antrostomy and deproteinised porcine bone mineral (DPBM) (control). Forty patients (30 female, 10 male) with a mean age of 50 years (range 25-71 years) and an alveolar ridge height between 4 and 7 mm were randomly allocated to test or control. Outcome measures included survival of suprastructures and implants, implant stability quotient, health status of the peri-implant tissue, peri-implant marginal bone loss, frequency of complications and PROMs using Oral Health Impact Profile-14 combined with questionnaires assessing patient's perception of the peri-implant soft tissue, implant crown, function of the implant, and total implant treatment outcome using visual analogue scale. Mean differences were expressed with standard deviation and 95% confidence interval. Level of significance was 0.05. All suprastructures and implants were well-functioning after 1-year of functional implant loading. No significant difference in any of the applied outcome measures was observed between test and control. Both treatments revealed high patient satisfaction scores and significant improvement in oral health-related quality of life. There were no significant differences in implant outcome and PROMs between test and control, after 1-year of functional implant loading. Neither of the treatments can therefore be considered better than the other. Thus, long-term randomized controlled trials are needed before definitive conclusions can be provided about the two treatment modalities.

Effect of bone density on the survival of 407 sandblasted and acid-etched dental implants: A retrospective multicenter study.

This study evaluated the success and survival rate of sandblasted and acid-etched dental implants according to the patient's bone quality. A multicenter retrospective study was conducted in five clinical centers between 2016 and March 2019. A total of 407 implants (KONTACTTM S, Biotech Dental, France) placed in 229 patients (61.5±12.9 years old) were included. Bone quality, classified as types D1 to D4 (Misch classification), maximal insertion torque, and bone loss were measured. The implant survival rate was evaluated after one year for the overall cohort and for each bone quality. The overall survival rate after four years was also estimated with a Kaplan-Meier analysis. After one year (12.8±9.6 months), eight implants were lost out of 407, representing an overall survival rate of 98%. It ranged from 100% for D1 to 89.7% for D4 (n=39), with significantly higher survival rates for D2 (n=93) and D3 (n=165) (98.9% and 98.2%, respectively) compared to D4. According to the Kaplan-Meier analysis, an overall survival rate of 96.5% was estimated after four years. An average maximal insertion torque of 45±12.6 N.cm and bone loss of 0.2±1.2 mm were measured. The high overall survival rate (98%), the average maximal insertion torque (45 N.cm), and the low marginal bone loss indicated good clinical results with acid-etched implants. Despite the relatively high survival rate for each bone quality, the significantly lower results in the D4 group highlight the expected benefits of bone quality-based implants and surgical protocols.

Cost-effectiveness analysis: nonsurgical root canal treatment versus single-tooth implant

BackgroundEconomic evaluation of nonsurgical root canal treatment (NSRCT) and single-tooth implant (STI) provides useful information for medical decision. This retrospective study aimed to evaluate the cost-effectiveness of NSRCT versus single-tooth implant (STI) after 5-year treatment in a university affiliated hospital in Beijing, China.Methods211 patients who underwent NSRCT and 142 patients who had STI were included and recalled after 5-year treatment. The propensity scores were used to match the cases of two treatment modalities. At recall, outcomes were determined based on clinical and radiographical examinations. For endodontically treated cases, absence or reduction of radiolucency were defined as success. Marginal bone loss (MBL) ≤ 4 mm were determined as success for implant cases. Direct and indirect costs were calculated in China Yuan (CNY). Patients’ willingness to pay (WTP) for each treatment modality was evaluated by questionnaires. A cost-effectiveness analysis was performed from the societal perspective.Results170 patients with 120 NSRCT teeth and 96 STI were available at recall. Based on propensity score matching, 76 endodontically treated teeth were matched to 76 implants. Absence of the radiolucency was observed in 58 of 76 endodontically treated teeth (76%) and reduction of the radiolucency in 9 of 76 teeth (12%) and altogether the success rate was 88%. 100% implants were detected with marginal bone loss (MBL) ≤ 4 mm. The cost advantage of NSRCT (4,751 CNY) over STI (20,298 CNY) was more pronounced. Incremental cost effectiveness ratio (ICER) was 129,563 CNY (STI-NSRCT) per success rate gained. It exceeded the patients’ willingness to pay value 7,533 CNY.ConclusionsClinical outcomes of NSRCT and STI could be predictable after 5-year treatment. NSRCT may be more cost-effective than STI for managing endodontically diseased teeth.

Narrow-diameter versus regular-diameter dental implants for mandibular overdentures: A systematic review and meta-analysis.

The aim of this systematic review was to compare treatment outcomes in terms of implant survival rate, marginal bone loss, and patient-reported outcome measures (PROMs) between narrow-diameter implants and regular-diameter implants (RDIs) for mandibular implant overdentures (MIOs). This study was based on the methodology adapted as per Cochrane. Medline, Embase, the Cochrane Central Register of Controlled Trials, Web of Science, and Scopus were searched for pertinent studies published by July 22, 2022. Outcome parameters included in this meta-analysis were implant survival rate, marginal bone loss, visual analogue scale score for patient satisfaction, and value of oral health impact profile. A total of 782 non-duplicate articles and 83 clinical study registrations were identified from database and hand searches, of which 26 were eligible for full-text searches. Finally, 12 publications reporting on 8 independent studies were included in this review. In the meta-analysis, implant survival rate and marginal bone loss did not significantly differ between narrow-diameter implants and RDIs. Regarding RDIs, narrow-diameter implants were associated with significantly better outcomes in general patient satisfaction and oral health-related quality of life than RDIs for mandibular overdentures. Narrow-diameter implants have competitive treatment outcomes compared to RDIs in terms of implant survival rate, marginal bone loss, and PROMs. [Correction added on July 21, 2023, after first online publication: The abbreviation RDIs was changed to PROMs in the preceding sentence.] Thus, narrow-diameter implants might be an alternative treatment option for MIOs in situations with limited alveolar bone volume.

Clinical, Radiological, and Aesthetic Outcomes after Placement of a Bioactive-Surfaced Implant with Immediate or Delayed Loading in the Anterior Maxilla: 1-Year Retrospective Follow-Up Study

Background: Dental implants have become the standard for replacing missing teeth. However, patients’ demands for shorter treatment times and the desire for aesthetics in their results can complicate the rehabilitation process, particularly when poor-quality bone is involved. In order to address these challenges, new methods of treating implant surfaces have been introduced. These methods aim to make the implants superhydrophilic and bioactive, enhancing their functionality and interactions with the surrounding tissues. Aim: The aim of the study was to retrospectively examine the efficacy of a superhydrophilic and bioactive implant for treatment of the edentulous maxillary anterior area. The study also aimed to evaluate whether this improved implant surface, by enhancing the osseointegration processes, could serve as a factor in speeding up the loading protocols. Materials and Methods: For this retrospective study, a total of 13 implants were included: 6 delayed restored implants and 7 immediately loaded implants placed in the anterior maxillary area. Clinical, radiographic, and esthetic outcomes were assessed. Baseline measurements of the insertion torque value (ITV) and stability implant quotient (ISQ) were recorded for all implants. In the early-loaded group, these measurements were also taken 30 days (t30) and 45 days (t45) after the placement of the implant to monitor their changes over time. Marginal bone loss (MBL) was calculated according to the changes in marginal bone level on intraoral X-rays taken at two different time points: at baseline and one year after loading. To evaluate the esthetic results, the pink esthetic score (PES) and the white esthetic score (WES) were assessed. For this evaluation, intraoral photographs were taken one year after implant loading. Results: A total of 7 implants were immediately restored, with a mean ITV of 32.29 ± 9.01 Ncm and a mean ISQ of 72.71 ± 2.81. These implants were placed in a bone environment with a mean density of 410.00 ± 194.42 HU. On the other hand, 6 implants with delayed loading had a mean ITV of 28.50 ± 3.27 Ncm, an ISQ of 67.92 ± 8.43, and a mean bone density of 607.50 ± 140.83 HU. The mean PES and WES after 1 year were, respectively, 8.71 ± 1.89 and 8.57 ± 0.79 for immediate and 8.33 ± 1.36 and 9.17 ± 1.33 for delayed-loaded implants. At 12 months after loading, the immediately loaded group had a MBL of 0.29 ± 0.29 mm, while the delayed-loaded group had a MBL of 0.33 ± 0.25. No statistically significant differences between the two treatment groups were found for any of the evaluated outcomes. Conclusions: Despite the limitations of this study, the obtained results may support the use of a superhydrophilic and bioactive implant surface for implant-prosthetic rehabilitation in critical loading protocols with satisfactory esthetic results.

Assessment of the Effect of Phototherapy and PRP on the Immediate Implants: An Original Research.

Immediate implants have been gaining popularity in recent times. There are many adjuvant techniques that are followed before implant placement, which have recently shown hopeful results. For this reason, the current comparative study analyzes the effectiveness of platelet-rich plasma (PRP) and photofunctionalization (PF) at a tertiary care dental hospital. In the current clinical trial, 30 subjects were grouped equally to receive immediate dental implants, with one group in which pretreatment of the extraction site was done with the auto-PRP and PF, while the control group received no pretreatment. For 12 months after the placement of the implant, the subjects were observed for alterations in the parameters. The variables analyzed were survival, esthetics, biological integration, and finally the success of the implants in each group. Values were noted and compared using the appropriate statistical tools, while keeping the level of significance at P < 0.05. For the variables of esthetics and survival, no substantial differences were observed in the PRP and PF groups. There was no difference between these experimental groups and the control group. However, there were significant differences for the biological variable as there was more marginal bone loss in the experimental groups. On the whole, the success was greater for the experimental groups than the control group, though not significant. The pretreatment protocols using PRP and PF have shown to improve some characteristics of the immediate implants in the anterior regions. However, further studies are suggested.

EFFECT OF VITAMIN D ON OSSEOINTEGRATION OF DENTAL IMPLANTS

Purpose. The aim of this study was to review the current literature to evaluate the effects of vitamin D on osseoin­tegration of dental implants in humans. Material and methods. The PRISMA Statement’s metho­dological guidelines were followed in the systematic re­view of the scientific literature. The Elsevier and PubMed databases were searched from October 2012 to October 2022 using different combinations of the following terms: dental implant, bone implant contact, vitamin D and os­seointegration. The current systematic review format was modified to primarily summarize the relevant data. Results. 3 prospective clinical studies with humans as subjects met the inclusion criteria. The amount of inser­ted titanium implants ranged between 32 to 122. It was shown that changes in the vitamin D concentration were positively linked with bone loss/growth at the implant site. Patients who took vitamin D supplements and had low vitamin D levels after the implant loading had a positive impact on bone level changes in the process of osseointegration. Conclusion. There is some evidence to support the con­cept that serum vitamin D levels may play a significant role in osseointegration, marginal bone loss, and success of dental implants. Further investigation is required to maintain these assumptions.

Three Years Evaluation of Single Versus Two Implants Retained Mandibular Overdenture Regarding Marginal Bone Loss, Gingival and Plaque Indices: A Randomized Controlled Clinical Trial

Three Years Evaluation of Single Versus Two Implants Retained Mandibular Overdenture Regarding Marginal Bone Loss, Gingival and Plaque Indices: A Randomized Controlled Clinical Trial

Delayed and Immediately Loaded Implants Placed in Fresh Extraction Socket - A Clinical and Radiological Study.

To present the outcomes of immediately loaded single implants placed in the anterior region compared to conventional protocol. 10 patients requiring single anterior tooth extraction was randomised either into immediate or delayed loaded group. Implants were positioned immediately after extraction and prosthesis was providing for the immediately loaded group. The cases were followed up for a period of 9 months at regular 3-month interval after the placement of definitive crowns. The parameters taken were probing depth, pain score and crestal marginal bone loss. A total of 10 AD1N-Touareg Spiral tapered Implant with spiral tap, 5 immediately loaded and 5 delayed loaded were evaluated. For immediate loaded cases, there was 0.93 ± 0.04 mm bone lost after 3 months, 1.26 ± 0.21 mm after 6 months and 1.72 ± 0.13 mm after 9 months. For delayed loading, there was 0.90 ± 0.02 mm bone lost after 3 months, 1.26 ± 0.15 mm after 6 months and 1.80 ± 0.07 mm after 9 months. Pain and probing depth showed gradual reduction in both the groups during the course of treatment. In the present study, the success rate and radiographic results of immediate loading of implants in freshly extracted sockets in the anterior region where comparable to those obtained from delayed groups.

Assessment of the Peri-Implant Conditions for the Primary and the Repeated Abutment Placements: An Original Research.

Recurrent abutment substitutions may physically irritate the mucosal (soft tissue) barrier, which may cause additional toxic irritants and germs to enter the mucosal implant barrier and weaken the tissues surrounding implant. The creation of a "definitive abutment" may lessen the likelihood of tissue losses around the implant. Determining the characters of the peri-implant tissue after the placement of the definitive abutments and multiple abutment replacement was the goal of this study. Forty missing teeth were replaced with implants in matched subjects. Parameters assessed were "distance of cement enamel junction to alveolar crest and distance of CEJ to gingival margin; bleeding on probing, Sulcus probing depth, and peri-implant marginal bone loss." Subjects were randomly assigned for the two groups of intervention. All the measurements were documented at designated timelines and compared for the statistical variance where P < 0.05 was considered as significant. In the control and test groups, the peri-implant marginal bone level rose from baseline to 3 months. There were no appreciable differences between the CEJ-AC and CEJ-GM groups when the clinical and radiographic parameters of each group were evaluated. Throughout all of the time points, the soft tissue borders in both groups remained comparably steady. The study's findings suggest that using implants with definite abutments is more advantageous for obtaining better maintenance in terms of the health of the tissues that surround the implants.

Radiographic and Clinical Evaluation of Implant Prosthetic Treatment with One Piece versus Two Piece Dental Implants: A Comparative Prospective Study.

Dental implants are designed to ensure natural tooth replacement based on improved design, simplified placement, and long-term survival. This study aimed to compare one-piece implant (OPI) and two-piece implant (TPI) to determine the success rate over the TPI. This study conducted on 15 patients selected with the age range of 20-60 years to place OPI and TPI. The surgical consent form duly signed by the patients was procured. The implants used were of Adin Implant System, and a follow-up examination was done at 3, 6, and 9 months after implant loading and various clinical and radiographic parameters were noted for both OPI and TPI. The clinical parameters measured were Silness, and Loe gingival index and probing depth and the radiographic parameters included crestal marginal bone loss. Independent Sample t-test and ANOVA were used for statistical analysis. The statistical analysis showed no significant difference between the OPI and TPI based on the gingival index, probing depth, and crestal bone loss. On the contrary, there was a statistical significance in comparing the same parameters during the follow-up period of 3, 6, and 9 months. Over a protracted period, OPIs are better than TPIs by the design and placement procedure. Further research with a higher sample size shall possibly establish esoteric results on a large scale.

The Use of a Soft Tissue Substitute at Immediate Postextractive Implants to Reduce Tissue Shrinkage: One-Year Results from a Randomized Controlled Trial.

The aim of this randomized controlled trial (RCT) was to evaluate whether placement of a soft tissue graft substitute (STGS) could decrease peri-implant tissue shrinkage at immediate postextractive implants. Twenty patients with one missing tooth between two adjacent healthy teeth in esthetic areas and at least 4 mm of bone apical to the tooth apex were randomly allocated (after tooth extraction) to receive (n = 10; test group) or not receive (n = 10; control group) a subepithelial buccal STGS. Implants were inserted with a torque of at least 30 Ncm, and sites were grafted with a cancellous particulate allograft. All patients were restored with nonoccluding immediate provisional screw-retained crowns, replaced after 6 months by definitive metal-ceramic crowns. One year after loading, no dropouts, crown or implant failure, or complications occurred. No statistically significant difference or trends in volume shrinkage, esthetics, peri-implant marginal bone loss, and keratinized mucosa heights between the two groups were observed. Acknowledging that the sample size was small, no clinical benefit could be observed for the use of a STGS in immediate postextractive implants.

Evaluation of Peri-Implant Parameters and C-Reactive Protein Levels among Patients with Different Obesity Levels.

Assessment of correlation between peri-implant parameters and C-reactive protein levels among patients with different obesity levels. Evaluation of 60 subjects was performed who were scheduled to undergo dental implant therapy for missing mandibular first molars. Three study cohorts were formed, namely, Group A: obese group (BMI between 30 Kg/m2 and 34.9 Kg/m2), Group B: high obese group (BMI over 34.9 Kg/m2), and Group C: non-obese group (BMI under 25 Kg/m2). Each cohort comprised 20 subjects. Dental implant therapy was carried out in all the patients. Peri-implant variables were evaluated in all the patients. Blood samples were obtained, and C-reactive protein levels in subjects having different obesity levels. Statistical analysis was performed using SPSS software. Mean serum C-reactive protein levels among patients of groups A, B, and C occurred to be 3.28 mg/L, 3.65 g/L, and 3.61 g/L, respectively. On comparing numerically, noticeable outcomes were achieved. Mean probing depth among subjects of groups A, B, and C occurred to be 2.9 mm, 3.2 mm, and 1.3 mm, respectively. Mean marginal bone loss among subjects of groups A, B, and C occurred to be 2.1 mm, 2.7 mm, and 0.8 mm, respectively. On comparing numerically, noteworthy outcomes were gathered. There were significantly higher deranged peri-implant inflammatory variables among patients with higher levels of obesity.

Can the Position of the Impacted Third Molars Be an Early Risk Indicator of Pathological Conditions? A Retrospective Cone-Beam Computed Tomography Study.

The aim of this retrospective study was to evaluate the prevalence of pathologies associated with impacted third molars in relation to tooth position on cone-beam computed tomography images. In 348 cone-beam computed tomography images, the position of 640 impacted third molars (mesiodistal angulation, buccolingual inclination, impaction depth, and contact point localization) and the presence of pathologies (distal caries, external root resorption, marginal bone loss, and pathological follicular space) were evaluated. The data were analysed statistically with a significance level set at P < 0.05. Distal caries was mostly detected in relation to Class A (20.4%) and contact point at (12.5%) and above (10.5%) the cementoenamel junction (CEJ) (P = 0.000; P < 0.05). External root resorption and marginal bone loss were more common in mesioangular angulation (52.3% and 80.1%, respectively), Class C (53% and 73.8%, respectively), and contact point below the CEJ (53.2% and 73.3%, respectively) (P = 0.000; P < 0.05). Lingual inclination was identified as a new risk factor for associated pathologies (P < 0.05). Pathological follicular space was significantly more likely to occur in those with inverted angulation (100%) and absence of contact (31.5%) (P = 0.000 and P = 0.010, respectively; P < 0.05). Pathologies arising in second molars in relation to impacted third molars are significantly associated with the three-dimensional position of impacted third molars, and watchful monitoring or prophylactic removal of impacted third molars should be considered, taking into account the relevant risk parameters for the related pathologies.

Marginal bone loss in implant placement among Indian patients with fresh extraction socket.

It is of interest to examine the Marginal Bone Loss (MBL) around a single titanium implant that was immediately loaded and implanted in a healed or new extraction site in the maxilla over a period of five years. This study involved 36 participants (21 men and 15 women, with an average age of 31 years), all of whom needed to have a single implant placed in the front maxillae. The average marginal bone loss (MBL) in extraction sockets increased by 0.27±0.18 mm after a year, 0.26± 0.17 mm after three years, and 0.21 ±0.18 mm after five years. The mean change in MBL for the group of healed ridges was 0.27± 0.18 mm for one year, 0.22±0.18 mm for three years, and 0.21± 0.17mm for five years. Thus, implants loaded immediately and positioned in either healed ridges or extraction sockets had a similar effect on the local bone.

COMPARATIVE EVALUATION OF CRESTAL BONE LOSS AROUND SUBMERGED AND NON-SUBMERGED IMPLANTS WITH DIFFERENT TYPES OF HEALING ABUTMENT DESIGNS - AN IN VIVO STUDY

Successful osseointegration is observed predictably for submerged implants requiring a two-stage procedure as well as for non-submerged implants characterized by one-stage surgical procedure. This study was aimed at evaluating and comparing crestal bone alterations around submerged and non-submerged implant radiographically. Total 45 patients aged between 20 to 50 years with missing mandibular posterior teeth were divided into 3 groups [Submerged implants (n=15), Non-submerged implants with anatomic healing abutment (n=15) and Non-submerged implants with esthetic healing abutment (n=15)]. Radiographic evaluation of mesial and distal marginal bone loss was done at 1 month and 3 months. Statistically significant differences were found between submerged dental implants and non-submerged dental implants with anatomical type of healing abutment designs (P &lt; 0.001) and between the two non-submerged dental implant groups with different types of healing abutments (P &lt; 0.001) at 1 month and 3 months. But there was no statistically significant difference between submerged dental implants and non-submerged dental implants with esthetic type of healing abutments (P &gt; 0.05) at 1 month and 3 months. It was concluded from this study that bone resorption during the osseointegration period using the non-submerged technique varied significantly depending on the morphology of the healing abutment used. The non-submerged technique with an esthetic healing abutment produced an equally predictable outcome compared with the submerged technique.

Survival rate and clinico-radiographic parameters around narrow-diameter dental implants for fixed dental prostheses in the posterior regions: A systematic review.

Narrow-diameter dental implants (NDDIs) are suggested to be a reliable alternative to bone augmentation techniques, but the evidence regarding the feasibility of NDDIs in the posterior area is limited. This review investigated the survival rates of NDDIs, as well as peri-implant clinical and radiographic parameters for fixed dental prostheses in the posterior regions in comparison with standard-diameter dental implants (SDDIs). One investigator performed an electronic search of the English literature until December 2020 in the Web of Science, PubMed, Scopus, and EMBASE databases. The focused question was: "Do narrowdiameter dental implants restoring a fixed dental prosthesis demonstrate more alveolar bone loss as compared to standard-diameter dental implants in posterior maxillary and mandibular regions?" The 9 studies selected for this review assessed a total of 498 patients (250 males and 206 females; 42 patients not described in terms of gender) aged 19-81 years, with 725 NDDIs and 260 SDDIs placed. The mean follow-up duration was 71 months (range: 12-176 months). A high survival rate of NDDIs was noticed (97.4%; range: 94.7-100%). The mean probing depth (PD) and bleeding on probing (BOP) scores ranged between 3.12 mm and 3.67 mm, and between 10.00% and 33.42%, respectively. However, the only study reporting the plaque index (PI) demonstrated a mean PI score of 1.39. The majority of the studies reported the mean marginal bone loss (MBL) scores below 1 mm. In conclusion, NDDIs appear to be a feasible treatment option in patients requiring a fixed dental prosthesis in the posterior region, since they exhibit comparable survival rates to SDDIs, as well as a clinically acceptable peri-implant clinical and radiographic tissue response.

Hybrid Prosthesis versus Overdenture: Effect of BioHPP Prosthetic Design Rehabilitating Edentulous Mandible.

To compare the BioHPP (biocompatible high-performance polymer) as a substructure for the hybrid prosthesis versus the BioHPP bar supporting and retaining implant overdenture by radiographic evaluation to identify bone height alteration around the implants and to evaluate satisfaction based on visual analoge scale questionnaire. Ill-fitting mandibular dentures were chosen for 14 fully edentulous male patients with adequate dental hygiene, enough interarch space, and free of systemic diseases and parafunctional habits. Patients who received new dentures (CDs) were randomly allocated into each group using computer software, and four interforaminal implants were inserted in parallel using a surgical guide. Three months after osseointegration, the patients received either CAD-CAM BioHPP framework hybrid prosthesis (Group I) or BioHPP bar supported and retained overdenture (Group II). Using digital preapical radiography, the bone loss is evaluated 6, 12, and 18 months after insertion. The subjective patient evaluation was done using a questionnaire based on the VAS includes five points for chewing, comfort, esthetics, speech, oral hygiene, and general satisfaction. The overall marginal bone loss (MBL) revealed that Group I (hybrid prosthesis) was more than Group II (bar overdenture) at all intervals in the anterior and posterior implants' mesial and distal surfaces. The patient satisfaction survey results showed that, after 18 months, the difference was statistically not significant between them all (P > 0.05) except for the comfort (for the overdenture group, 4.43 ± 0.53 while the fixed hybrid was 5.00 ± 0.00). BioHPP framework material is an alternative material for implant rehabilitation of edentulous mandible with minimal MBL in BioHPP bar overdenture compared to BioHPP hybrid prosthesis.