A Socket Seal Technique With the Use of Autologous Dental Roots for Socket Seal: A Case Series.

The literature identified variations in socket seal surgery, each with limitations. This case series aimed to observe the outcome of using autologous dental root (ADR) for socket sealing on socket preservation (SP). A total of 9 patients with 15 extraction sockets were documented. After flapless extraction, the xenograft or alloplastic grafts were placed in the sockets. Autologous dental roots were prepared extraorally and applied to seal the socket entrance. All SP sites healed uneventfully. Cone-beam computed tomography (CBCT) scan was performed after 4-6 months of healing to evaluate ridge dimensions. The preserved alveolar ridge profiles were verified on CBCT scans and during implant surgery. Implants were placed successfully with a reduced need for guided bone regeneration. Histological biopsy specimens were examined in 3 cases. The histological examination demonstrated vital bone formation and osseointegration of graft particles. All patients completed the final restorations and were monitored for 15.56 ± 9.08 months after functional loading. The favorable clinical outcomes support the use of ADR for SP procedures. It was not only accepted to patients but also easy to perform with low complication rates. The ADR technique is thus a feasible method for socket seal surgery.

Convergent angles of a tapered implant referred from the root profile of premolars.

Background/purpose: Limited studies have discussed the convergent profiles regarding tapered implants based on biological considerations. This study analyzed the convergent angles (CAs) of premolar roots and imitated a tapered implant according to the anatomy of tooth roots. Materials and methods: A total of 60 single-rooted premolars were explored by micro-computed tomography. Every individual root was divided into 10 segments corono-apically, and the roots' buccolingual (BL) and mesiodistal (MD) CAs were measured by sections. To mimic a dental implant, the irregular shape of examined root cross-sections was transformed into a circular shape with equal areas. A biomimetic dental implant (BDI) was reconstructed and its CAs were compared with those of the natural roots' BL and MD at the examined levels and overall estimation. Results: In general, the maxillary and mandibular premolars demonstrated comparable CA patterns. However, significantly different CA patterns of BL, MD, and BDI were developed for both the maxillary and mandibular roots at the examined levels. The BL's CAs were greater than those CAs measured from the BDI and MD aspects, particularly for the sections at the middle and apical thirds of the roots. For overall CAs, the BDI's CAs were comparable with the average CAs of the BL and MD for both premolar groups. Conclusion: Instead of a cylindrical configuration, the BDI prototype demonstrated a tapered model with a continuous slope. The average CA of BDI was 14°-24°, serving as a biological reference for future tapered implant design and research.

The developing patterns of calibrated implant stability quotients of posterior implants.

BACKGROUND/PURPOSE: Many surgical protocols were modified to improve implant stability. However, the conclusions of applying osteotome condensation technique could enhance implant stability were controversial. The evaluated implant stability quotients (ISQ) were calibrated to differentiate the implant stability improvement that applied by varied surgical techniques and the bone quality at recipient sites. Therefore, this study examine the developing patterns of calibrated ISQ values induced by osteotome bone condensation and conventional drilling technique at the posterior ridges. MATERIALS AND METHODS: The ISQ values of 4.1/4.8-mm diameter implants were calibrated by 3.3-mm diameter implants (ISQb). Osteotome condensation technique was applied on the sites with ISQb ≤ 65 while those with ISQb > 65 were treated with conventional drilling technique. The implant ISQ values at Week 0, 1, 2, 3, 4, 6, 8, 10, 12 were recorded. The detected and calibrated ISQ values were statistically analyzed. RESULTS: Maxillary 14 implants and mandibular 16 implants using osteotome technique, maxillary 15 implants and mandibular 16 implants with conventional drilling technique were studied. Both techniques showed a generally similar ISQ developing pattern at both arches. Without calibration, significantly less ISQ values were noted for the osteotome technique of posterior maxilla at initial four weeks; subsequently, both techniques presented a comparable ISQ developing pattern. Osteotome technique demonstrated a greater ISQ increase after calibration on both arches (p < 0.05). All implants reached an ISQ stability plateau between Week 8 and 10. CONCLUSION: With calibration, osteotome condensation technique could enhance greater primary and secondary implant stability for both arches.

Characteristics of the convergent angles of tapered implants based on a premolar root model.

STATEMENT OF PROBLEM: Developing tapered implants with the most appropriate angular characteristics requires an improved analysis of the anatomy of premolar roots. PURPOSE: The purpose of this observational study was to analyze the 3D anatomy of premolar roots by determining the tapered slope and convergent angle (TS/CA), to transform the TS/CA patterns into those in which the tapered implants mimic natural tooth roots, and to provide TS/CA references for future investigations. MATERIAL AND METHODS: A total of 73 human single-rooted premolars were surveyed and analyzed by microcomputed tomography and an associated software program. The 3D root surface area (RSA), the radius/diameter (R/D) at the planned first to tenth millimeter levels apical to the cementoenamel junction (CEJ), and the TS/CA at corresponding levels were calculated. The results were statistically analyzed by using an independent samples t test to assess the general differences of tested parameters between maxillary and mandibular premolars. A paired t test was used to examine the significant intragroup TS/CA differences between sequential coronoapical levels. One-way ANOVA was applied to study the general significance of developmental patterns in maxillary and/or mandibular groups. Two-way ANOVA was used to inspect the TS/CA significance at various measurements coronoapically between the maxillary and mandibular premolars (α=.05). RESULTS: Generally, the RSA, root length, R/D, and TS/CA parameters examined for the maxillary premolar roots differed significantly from those for the mandibular roots at the evaluated levels (P<.05). According to the measurements, the maxillary premolar roots generally exhibited nonsignificant RSA and R/D reduction patterns, with a decreasing angle of TS=13.44 degrees and CA=24.53 degrees coronoapically. However, mandibular premolar roots exhibited a significant reduction pattern, with TS=11.25 degrees and CA=21.06 degrees coronoapically according to both individual and general evaluations. CONCLUSIONS: Based on the developmental patterns of the evaluated TSs/CAs, tapered implants imitating premolar root anatomy should have a conical rather than a cylindrical shape, and the R/D of these models should be reduced to half at the apical third. However, further studies are warranted to identify more TS/CA characteristics related to the tapered implants, including the TSs/CAs of other tooth types.

The correspondence of 3D supporting bone loss and crown-to-root ratio to periodontitis classification.

AIM: Assessing the application of three-dimensional clinical attachment loss (3D-CAL), 3D supporting bone loss (3D-SBL), supracrestal tissue attachment (STA), and crown-to-root ratio (CRR) in evaluating the 2017 periodontitis classification. MATERIALS AND METHODS: We analysed ninety single-rooted human premolars with micro-computed tomography. The amount of 3D-SBL, linear radiographic bone loss (RBL), and CRR corresponding to various periodontitis stages as well as the statistical significance was investigated. RESULTS: From a 3D perspective, the premolars with a 21% of 3D-SBL at 2.0 mm coronal root length (RL) and 15% RBL corresponded to the periodontitis stage I. Premolars with a 44% of 3D-SBL at coronal 4.2-4.4 mm RL and 33% RBL accorded with the periodontitis stage II. Excluding the consideration of STA, CRR = 5:6 and 4:3 were associated with the levels at 15% and 33% RBL, respectively. CONCLUSIONS: A greater percentage of 3D-CAL than that of 2D-CAL is significant at evaluated levels. It is feasible to correlate the 3D-SBL, 3D-CAL, and STA parameters to evaluate the stages of periodontitis severity. However, the current use of RBL and CAL as applied for staging in the 2017 classification might be inconsistent with the evaluated premolar roots length, when STA dimensions are considered.

Assessment of pain perception following periodontal and implant surgeries.

OBJECTIVE: To evaluate patients' pain perception following periodontal or implant surgery and to explore risk factors associated with post-surgical pain. MATERIALS AND METHODS: Patients undergoing periodontal or implant surgery were recruited. Post-surgical pain perception was evaluated by a numeric rating scale (NRS, 1-10) after 1 week. Self-reported durations of pain (DOP) and of swelling (DOS), and consumption of prescriptions were also recorded. Demographic and surgical variables were compared between the groups of mild (MP) and moderate-to-severe post-surgical pain (SP). Factors associated with SP were analysed statistically. RESULTS: Ten surgical types in three categories, comprising 330 surgeries in 253 patients, were included. Overall, 70.3% of the subjects experienced MP, 25.5% experienced moderate pain and 4.2% experienced severe pain. The highest median NRS score was found in subjects having advanced implant surgery [4.0, interquartile range (IQR) 4.00] and the lowest in open flap debridement surgery (1.0, IQR 1.00). The median DOP was 2.0 days (IQR 2.00). Analgesic need (median = 2.0 days, IQR 4.00) was correlated with the DOP (r = 0.406, p < 0.01) and the NRS score (r = 0.358, p < 0.01). Subjects receiving periodontal plastic surgery (OR = 3.20, 95% CI = 1.06-9.71), complex surgery (OR = 2.63, 95% CI = 1.31-5.25), increased surgical extension (OR = 1.78, 95% CI = 1.21-2.62) and increased anaesthesia (OR = 2.32, 95% CI = 1.13-4.76) were more likely to experience SP. CONCLUSIONS: The majority of patients perceived mild post-surgical pain, but the pain level varied among different surgical procedures. Periodontal plastic surgery, complex surgery, surgical extension and anaesthetic volume were associated with more pain.

Meta-regression analysis of the initial bone height for predicting implant survival rates of two sinus elevation procedures.

AIM: To undertake a systematic review for the association between the initial alveolar bone height and the success of dental implants with sinus elevation procedures. MATERIALS AND METHODS: An online search was performed using the following electronic databases: PubMed, Medline, Science Direct, and Blackwell synergy. Two investigators independently assessed publications for inclusion and extracted data. Meta-regression analyses were used to test the associations between the initial alveolar bone height and implant survival with lateral window or osteotome sinus elevation procedures. RESULTS: Of 635 studies, 21 were included for analysis. A quadratic curve-fitting meta-regression showed an increasing trend of implant survival rate with greater initial bone height for the lateral window technique (p<0.0001, adjusted R(2)=0.97). The result of the meta-regression for hazard rates showed a decreasing trend (p=0.0041, adjusted R(2)=0.89). No association was found for the osteotome technique. CONCLUSIONS: For the lateral window technique, meta-regression analysis suggested a positive association between the initial alveolar bone height and implant survival rates. No relationship was found between the initial alveolar bone height and implant survival rate for the osteotome technique due to a lack of data below 4 mm of initial bone height.