Free-hand versus computer-guided implant placement: early implant failures in a case-control study.

OBJECTIVE: To evaluate the survival of fully guided implants placed with a hollow tooth-supported computerized surgical guide (TSSG). MATERIALS AND METHODS: This retrospective study included 94 patients who underwent implant placement using freehand (FH) or tooth-supported computerized surgical guide (TSSG) by the same operator between 2015 and 2020. Early implant failures occurring within one-year post-rehabilitation were assessed. RESULTS: In the study, two types of implants were placed using two different techniques: TSSG and FH. The TSSG group consisted of 84 S implants and 100 LP implants, while the FH group included 90 S implants and 94 LP implants. The results showed that more implants survived when placed FH compared to TSSG (181 (98.4%) vs 172 (93.5%) respectively, p < 0.05). The only significant factor affecting the success rate was the type of implant, with LP implants having a higher survival rate in the TSSG group (p < 0.05). CONCLUSION: Surgeons should consider the impact of implant type on survival rates when utilizing the TSSG system.

Computer-assisted periodontal classification vs manual classification among dental students: a comparative pilot study.

OBJECTIVE: The objective of the study was to assess whether computer-assisted periodontal diagnosis can improve the accuracy and homogeneity of classification results obtained by dental students using the 2017 classification of periodontal diseases. METHOD AND MATERIALS: All final year predoctoral dental students from two dental schools were invited to participate in the study. Participants who volunteered for the study were randomly divided into two groups for digital or manual diagnosis, and each participant classified 48 cases. A group of three experienced periodontists provided the reference or gold standard diagnosis. RESULTS: Overall, 27 students completed the evaluation of all cases; 14 students comprised the digital application group and 13 the manual group. The accuracy of the classification results compared with the gold standard committee was 82% for the digital group compared to 50% of the manual group in terms of the extent of gingivitis; 71% vs 56% for the stage of periodontitis; 67% vs 62% for grade of periodontitis; 76% vs 63% for extent of periodontitis; and 43% vs 30% for overall diagnosis accuracy of periodontitis cases respectively. CONCLUSIONS: Computer-assisted classification using newly developed software, within the boundaries of this study, was shown to be a sensible support tool for dental practitioners to use when diagnosing periodontal disease. This digital tool can the clinicians' accuracy of diagnosis primarily in the extent and staging of periodontitis.

Evaluation of Implant Stability and Trephination Depth for Implant Removal-An In Vitro Study.

Malpositioned and broken implants are usually fully osseointegrated; hence, their removal, especially from the lower arch, can be very challenging. Implant removal techniques include reverse torque and trephination. Trephination is an invasive technique that can jeopardize vital structures, cause mandibular fatigue fractures, or lead to osteomyelitis. In this study, we aimed to assess the relationship between trephination depth and implant stability by recording implant stability quotient (ISQ) readings at varying trephination depths in vitro. Materials and methods: Forty-eight implants were inserted into dense synthetic polyurethane foam blocks as artificial bone. Primary implant stability was measured with a Penguin resonance frequency analysis (RFA) device. Implants of two designs with a diameter of 3.75 mm and a length of 13 or 8 mm were inserted. Twenty-four internal hexagon (IH) (Seven®) and twenty-four conical connection (CC) implants (C1®; MIS® Implants, Ltd., Misgav, Israel) were used. The primary implant stability was measured with the RFA device. Trephination was performed, and implant stability was recorded at depths of 0, 3, and 6 mm for the 8 mm implants and 0, 3, 6, 8, 10, and 11.5 mm for the 13 mm implants. Results: Linear regression revealed a significant relation between the trephination depth and the ISQ (F (1, 213) = 1113.192, p < 0.001, adjusted r2 = 0.839). The trephination depth significantly predicted the ISQ (ß = −5.337, p < 0.001), and the ISQ decreased by −5.33 as the trephination depth increased by 1 mm. Conclusion: Implant stability reduction as measured using an RFA device during trephination may be a valuable guide to achieving safe reverse torque for implant removal. Further studies are needed to evaluate these data in clinical settings.

Primary Implant Stability Analysis of Different Dental Implant Connections and Designs-An In Vitro Comparative Study.

Primary implant stability can be evaluated at the time of placement by measuring the insertion torque (IT). However, another method to monitor implant stability over time is resonance frequency analysis (RFA). Our aim was to examine the effect of bone type, implant design, and implant length on implant primary stability as measured by IT and two RFA devices (Osstell and Penguin) in an in vitro model. Ninety-six implants were inserted by a surgical motor in an artificial bone material, resembling soft and dense bone. Two different implant designs-conical connection (CC) and internal hex (IH), with lengths of 13 and 8 mm, were compared. The results indicate that the primary stability as measured by RFA and IT is significantly increased by the quality of bone (dense bone), and implant length and design, where the influence of dense bone is similar to that of CC design. Both the Osstell and Penguin devices recorded higher primary implant stability for long implants in dense bone, favoring the CC over the IH implant design. The CC implant design may compensate for the low stability expected in soft bone, and dense bone may compensate for short implant length if required by the anatomical bone conditions.

Positive relationship between the dimensions of clinical gingival recessions and associated alveolar bone dehiscences: a biometric study.

OBJECTIVES: To analyze the relationships between the dimension of clinical gingival recession and of the actual bone dehiscence. METHOD AND MATERIALS: Data included measurements taken before and during root coverage surgical procedures. General health, smoking status, previous orthodontic treatment, probing depth, clinical measurements taken on gingival recessions, and the exposed alveolar bone dehiscences were recorded. Data were analyzed using descriptive statistics and linear regression model. RESULTS: Twenty-three patient files were available. The mean age was 31.3 ± 12.1 years (range 13 to 51 years). Eight patients had previous orthodontic treatment. Incisor, canine, and premolar recessions amounted to 9, 8, and 6 teeth, respectively. The deepest recession per patient was recorded. The mean alveolar bone dehiscence depth was 6.78 ± 1.2 mm (range 5 to 9 mm). Patient-related or systemic findings, preceding orthodontic treatment, and tooth type were not correlated with alveolar bone dehiscence dimensions. A significant association was found between clinical recession and the alveolar bone dehiscence depths (P < .001, Fisher exact test). On average, each 1 mm increase in clinical recession depth involved an increase of 1.45 mm in alveolar bone dehiscence depth (P < .001, linear regression). The ratio between the clinical recession depth and width was significantly associated with the depth of the bone dehiscence (P = .007, Fisher exact test). CONCLUSION: Within the limitations of the size of this study, clinical recession depth and width dimensions may help to predict the underling bone dehiscence magnitude. Gingival recession is associated with deformities of the underlying alveolar bone; this may be revealed during mucogingival procedures associated with full-thickness flaps. The association between the two may be of particular value to the operator as it may significantly affect the outcome of treatment. Furthermore, this relationship is of utmost importance in minimally invasive procedures that avoid flap elevation. A significant association was found between the depth of the clinical gingival recession and that of alveolar bone dehiscence. In addition, the ratio between the clinical recession depth and width was significantly associated with the depth of the bone dehiscence. Clinical recession depth and width dimensions may serve as an assessment predictor for the underling bone dehiscence magnitude.

Histologic and Histomorphometric Evaluation of a Connective Tissue Graft Retrieved with a Novel Deepithelialization Procedure: A Case Series.

Various free connective tissue graft (CTG) harvesting techniques have been reported. The lining epithelium of the palatal graft may be retrieved either intra- or extraorally. This report presents a series of root coverage cases where deepithelialization was intraorally performed before harvesting the graft with a round diamond bur mounted on a low-speed handpiece. Ten single-tooth gingival recession defects in five patients were treated, applying a surgical procedure based on a coronally advanced flap combined with a free CTG that was deepithelialized in situ by the same method. Recession and probing depths and keratinized tissue and recession widths were recorded at baseline and the follow-up evaluations. Follow-up was between 7 and 21 months (mean: 12.1 ± 5.04 months). Clinical, esthetic, and histologic evaluations were performed. Mean root coverage was 89% ± 24.86% (range: 25% to 100%), and complete root coverage was observed in 80% of cases; the esthetic score range was 6 to 9 (mean: 7.44 ± 1.01). Epithelial remnants, although different in proportions, were evident in all samples (range of prevalence: 4.57% to 29.12%). Within the limitations of the small number of clinical cases, the presented in situ deepithelialization technique for CTG seems to be valuable and may accordingly be routinely applied.

Reliability and Correlation of Different Devices for the Evaluation of Primary Implant Stability: An In Vitro Study.

Our aim was to analyze the correlation between the IT evaluated by a surgical motor and the primary implant stability (ISQ) measured by two RFA devices, Osstell and Penguin, in an in vitro model. This study examines the effect of bone type (soft or dense), implant length (13 mm or 8 mm), and implant design (CC: conical connection; IH: internal hexagon), on this correlation. Ninety-six implants were inserted using a surgical motor (IT) into two types of synthetic foam blocks. Initial measurements for both the peak IT and ISQ were recorded at the point when implant insertion was stopped by the surgical motor, and the final measurements were recorded when the implant was completely inserted into the synthetic blocks using only the RFA devices. Our null hypothesis was that there is a good correlation between the devices, independent of the implant length, design, or bone type. We found a positive, significant correlation between the IT, and the Osstell and Penguin devices. Implant length and bone type did not affect this correlation. The correlation between the devices in the CC design was maintained; however, in the IH design it was maintained only between the RFA devices. We concluded that there is a high positive correlation between the IT and ISQ from a mechanical perspective, which was not affected by bone type or implant length but was affected by the implant design.

Patients' Perception of Recovery after Dental Implant Placement.

Background and Objectives: The success rates of surgical dental implant insertions are high. However, knowledge of patients' recovery is still lacking. "Health-related quality of life" (HRQOL) questionnaires are gaining popularity in all fields of medicine. The present survey assessed the perception of recovery after the surgical placement of dental implants. Materials and Methods: Forty individuals (26 women and 14 men; mean age, 55 ± 12 years) filled a questionnaire evaluating patients' perception of recovery for 7 consecutive days post-surgery. Confounding factors included age, gender, oral habits, smoking, bruxism, bone quality (tactile evaluation) and quantity, implant location, number of implants, implant type, length and diameter, one-stage vs. two-stage, and the need for bone grafting. Results: The most serious difficulties were found in swelling, which became minimal after 5 days, followed by eating everyday food, ability to enjoy everyday food, maximal pain and average pain (3 days); analgesics consumption (2.5 days); limitations in daily routine, mouth opening, and speech (2 days); swallowing and sleep (1.5 days); and, within 1 day, all other measures attained minimal levels. Gender, and implant location (anterior vs. posterior) were significant predictor variables exerting their different characteristic delayed recoveries. Conclusions: (1) Patients should expect, in general, recovery within 4 days after dental implant placement; (2) women will experience a delayed recovery, (3) implants placed in the intercanine area will result in postoperative eating difficulties for nearly one week, and (4) the number of implants placed during the same appointment has no effect on post treatment recovery.

Fibroblasts from the oral masticatory and lining mucosa have different gene expression profiles and proliferation rates.

AIMS: To compare the gene expression profiles and proliferation rates of fibroblasts from the oral lining and masticatory mucosae. MATERIALS AND METHODS: Primary human fibroblasts were retrieved from the posterior masticatory hard palate and the lining alveolar mucosa of five individuals. The gene expression profile was evaluated using total RNA sequencing. The proliferation rate was determined colorimetrically. RESULTS: Substantial differences in specific gene groups and pathways were observed between fibroblasts from the two tissues. Significantly enriched gene ontology processes were focused on the extracellular components. Lining mucosa fibroblasts exhibited significantly higher expression of the principal structural collagens, cranial neural crest markers, and homeobox genes associated with positional memory. Masticatory mucosa fibroblasts showed greater expression of genes related to transforming growth factor-ß signalling, which may be associated with fibrosis. In addition, they expressed higher levels of the EP2 prostaglandin E2 receptor and Toll-like receptor 1. Finally, masticatory mucosa fibroblasts exhibited a 10%-30% higher proliferation rate. CONCLUSIONS: Fibroblasts from the lining and masticatory oral mucosae are phenotypically heterogeneous, presenting distinct gene expression profiles and proliferation rates. These features may contribute to their specific physiological functions and have relevance for potential therapeutic applications.

Effect of root surface conditioning on gingival recession coverage with a connective tissue graft. A retrospective comparative study of three different agents.

OBJECTIVE: Different root modifiers have been proposed in the literature with an attempt to improve the healing process and the success rate of root coverage procedures. The aim of the present retrospective study was to evaluate the effect of three different types of root surface conditioning, namely, tetracycline (TTC), ethylene-di-amino-tetra-acetic acid (EDTA) and saline, on the outcome of root coverage procedures applying the same surgical technique. MATERIALS AND METHODS: Twenty-nine patients with 60 Classes I, II, or III recession defects were treated using connective tissue with a partial-thickness double-pedicle graft. In 21 recession defects root surface was treated with TTC and, in other 21, with EDTA, while in the remaining, saline solution was applied. Statistical analysis consisted of descriptive statistics and Kruskal-Wallis, Mann-Whitney, and chi-square tests. RESULTS: Differences between pre- and postoperative values were statistically significant only within but not between groups. Mean root coverage was 73.25%, 69.19%, and 82.17% in the TTC, the EDTA, and the saline groups, respectively. The study revealed no statistically significant differences for all evaluated parameters between groups. CONCLUSION: Within the limits of this study, root conditioning, prior to root coverage procedures, does not significantly affect their outcome. CLINICAL SIGNIFICANCE: Clinical outcome of root coverage procedures is not related to the type of root surface conditioning.

Root coverage of advanced gingival recession: a comparative study between acellular dermal matrix allograft and subepithelial connective tissue grafts.

BACKGROUND: Acellular dermal matrix allograft (ADMA) has successfully been applied as a substitute for free connective tissue grafts (CTG) in various periodontal procedures, including root coverage. The purpose of this study was to clinically compare the efficiency of ADMA and CTG in the treatment of gingival recessions > or = 4 mm. METHODS: Seven patients with bilateral recession lesions participated. Fourteen teeth presenting gingival recessions > or = 4 mm were randomly treated with ADMA or CTG covered by coronally advanced flaps. Recession, probing depth, and width of keratinized tissue were measured preoperatively and 12 months postoperatively. Changes in these clinical parameters were calculated within and compared between groups and analyzed statistically. RESULTS: Baseline recession, probing depth, and keratinized tissue width were similar for both groups. At 12 months, root coverage gain was 4.57 mm (89.1%) versus 4.29 mm (88.7%) (P = NS), and keratinized tissue gain was 0.86 mm (36%) versus 2.14 mm (107%) (P < 0.05) for ADMA and CTG, respectively. Probing depth remained unchanged (0.22 mm/0 mm), with no difference between the groups. CONCLUSIONS: Recession defects may be covered using ADMA or CTG, with no practical difference. However, CTG results in significantly greater gain of keratinized gingiva.