Effect of different access cavity designs on fracture toughness of endodontically treated teeth: a systematic review and network meta-analysis.

Objective To compare the effect of different endodontic access cavities on fracture toughness of extracted endodontically treated human teeth.Data/sources An electronic literature search was performed in seven databases as well as hand search until September 2020. Risk-of-bias tool was used to evaluate the quality of included studies. Random effects frequentist network meta-analysis was performed, with mean difference (MD) and 95% confidence interval (CI) as the effect measure. Confidence in the documented evidence was assessed through the newly fuelled Confidence in Network Meta-analysis (CINeMA) framework based on the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach.Study selection A total of 844 articles were obtained in the electronic and hand search. After the application of the eligibility criteria and duplicate removal, 14 studies were included in this systematic review. All included studies were in vitro that evaluated the influence of conservative endodontic cavities (CECs) on fracture toughness in extracted endodontically treated human teeth and compared to traditional endodontic cavities (TECs). In total, ten studies (n = 456) were included in the network meta-analysis for molars. The overall risk of bias was moderate.Results The results showed that when compared to intact teeth, the greatest reduction in fracture resistance was reported for TEC (MD: -927.52; 95% CI [-1304.80; -550.24]) and CEC showed least reduction in fracture resistance (MD: -365.59; 95% CI [-759.02; 27.83]). The surface under the cumulative ranking curve (SUCRA) value for intact teeth was highest (85.4% probability of being ranked as first), followed by CEC (51.4% probability of being ranked as second), with CEC presenting the highest probabilities to be the most effective access cavity design, according to the RANK (receptor activator of NF-kappaB) table. Level of confidence varied from low to moderate across all formulated comparisons.Conclusion Overall, based on the included in vitro studies in this systematic review, CEC was the most favourable access cavity design when compared to other (truss access cavities, TEC and ninja cavities) and TEC was the least favourable for fracture resistance; however, the level of evidence was moderate.

Comparison between conventional and piezocision-assisted orthodontics in relieving anterior crowding: a systematic review and meta-analysis.

BACKGROUND: Prolonged duration of orthodontic treatment is of great concern and poses risks to the teeth and surrounding tissues. Orthodontic tooth movement can be accelerated by introducing regional insult. Evidence suggests piezocision to be minimally invasive and clinically effective. OBJECTIVE: The aim of the present study was to compare the effectiveness of conventional and piezocision-assisted orthodontics in relieving anterior crowding. SEARCH METHODS: Electronic and manual searches were conducted in databases including PubMed, Dental and Oral Science, CINAHL, and Cochrane Central Register of Controlled Trials until April 2019. SELECTION CRITERIA: Randomized and non-randomized controlled trials were included. DATA COLLECTION AND ANALYSIS: Data were extracted independently by two authors from the studies that fulfilled inclusion criteria. The primary outcome assessed was time required for the alleviation of crowding. The secondary outcomes evaluated were pain, root resorption, and periodontal health. The risk of bias in the clinical trials was evaluated according to the Cochrane Collaboration's tool. Studies having homogenous data were included in the meta-analysis using the RevMan software. RESULTS: Initial search yielded 3018 studies with eight articles meeting the inclusion criteria, six were randomized controlled trials and two were non-randomized controlled trials. Significant differences were found in alignment time between conventional and piezocision-assisted orthodontic treatment. However, gingival health, pain experienced by the patient, and root resorption showed non-significant differences. The forest plot of meta-analysis depicted significant mean difference of -46.44; 95 per cent confidence interval (CI) -87.95, -4.93; P ≤ 0.03 in the alignment time. Difference in pain levels was found to be non-significant (P = 0.78). LIMITATIONS: There is a shortage of high-quality randomized controlled trials with a limited sample size and lack of standardization of piezocision protocol. CONCLUSIONS AND IMPLICATIONS: According to the existing evidence, piezocision is effective in reducing tooth alignment time and alleviating crowding when compared to conventional therapy. Pain levels showed insignificant differences revealed in meta-analysis. Weak evidence suggests that there are no negative effects on periodontal health and root resorption after performing piezocision. REGISTRATION: PROSPERO (CRD42019134398).

Management of immature necrotic permanent teeth with regenerative endodontic procedures - a review of literature.

Immature necrotic permanent tooth presents a distinctive challenge for the endodontist. Various treatment modalities have been employed to create hard tissue barrier at the apex, which includes non-vital pulp therapy with calcium hydroxide, apexification with mineral trioxide aggregate, pulp revascularisation and regeneration. Regenerative endodontics is a novel modality which involves physiological replacement of the damaged structures of tooth like dentin, root and cells of the pulp-dentin complex. Numerous published case reports have revealed increased dentinal wall thickness, continued root development and apical closure, but there is still lack of sound scientific evidence regarding histological nature of the type of tissue. The current literature review was planned to summarise the evidence regarding the treatment of immature necrotic permanent teeth by regenerative endodontic procedures.

Vertical Ridge Gain with Various Bone Augmentation Techniques: A Systematic Review and Meta-Analysis.

PURPOSE: The aim of this systematic review was to determine the most effective alveolar augmentation technique for vertical bone gain. MATERIALS AND METHODS: A systematic search to select clinical trials and retrospective studies done on patients with reduced vertical bone height was conducted. The intervention of interest was autogenous block graft done compared to procedures such as distraction osteogenesis (DO), particulate grafting, block plus particulate grafting with titanium mesh, and tent pole technique in systematically healthy adult patients age 18 and older. The following electronic databases were explored: PubMed, CINAHL, and Dental and Oral Science. A supplementary manual search of published full-text articles from January 2005 to December 2017 was done using Google Scholar. Grey literature was also sought using greylit.org. The review protocol was registered at the Prospero registry (CRD # 42017072432). The risk of bias of the included studies was assessed using EPOC criteria. Meta-analysis was performed using Review Manager for studies with quantitative data on mean values of vertical bone gain and bone resorption achieved with various bone augmentation techniques. Random effect model was used. Heterogeneity among studies was evaluated using the I2 statistic. RESULTS: A total of 2322 articles were found. After excluding the irrelevant papers, only 8 papers were finally selected for the detailed evaluation. Of these 8, 5 were clinical trials, and 3 were retrospective studies. Four studies were on DO, 2 on particulate grafting, 1 on autogenous block grafting plus particulate grafting, and 1 on tent pole grafting. The control group in all studies were autogenous block graft. Meta-analysis revealed no significant difference between DO and autogenous block grafting for vertical bone gain (mean difference 0.82 [-1.28, 2.91]). Similarly, no significant difference was observed in the 2 techniques for bone resorption (mean difference 0.38 [-0.23, 0.99]). CONCLUSIONS: DO was not superior to autogenous block grafting for vertical bone augmentation. Both techniques were associated with a number of complications. There was no difference in the bone resorption observed in the 2 techniques. No conclusive results can be drawn on other techniques on account of limited data.

Prosthetic rehabilitation of edentulous mandible with two-implant retained fixed hybrid prosthesis: A case report.

Removable complete dentures have been the most costeffective treatment option for edentulous jaws since decades. However, certain problems are encountered by the patients such as stability of the lower dentures resulting in poor masticatory efficiency. Ridge resorption and inadequate bony support are the long-term complications comprising the stability of the denture and patient finding it difficult to control denture movement during speaking and eating reducing patient compliance. Mandibular implant retained over dentures or hybrid dentures have shown to be better alternatives in terms of retention, stability and patient satisfaction. Two implants provide cost-effective, stabilized and comfortable treatment options. The present case report discusses the management of the patient with compromised dentition in which all teeth were extracted followed by conventional upper complete denture and lower two implant supported fixed hybrid dentures with splinted bar attachment.

Assessment of contamination on sterilised dental burs after being subjected to various pre-cleaning methods.

OBJECTIVE: To determine the effectiveness of different pre-cleaning methods by determining frequency and site of contamination on the sterilised dental burs using Phloxine B dye. METHODS: The in-vitro experimental study was conducted from June to August 2017 at dental clinics of Aga Khan University Hospital Karachi. Diamond dental burs were selected and divided into two control and four test groups. The two control groups were classified as Negative (new burs) and Positive (used contaminated). The four test groups were classified as Manual (Group-1), Ultrasonic (Group-2), Manual + Enzyme (Group-3) and Manual + Ultrasonic (Group-4). Phloxine B dye was used to determine the contamination. The images of the burs were taken and enlarged at 15X before subjected to visual assessment. Association between contamination and pre-cleaning methods were determined. Data was analysed using SPSS version 22. RESULTS: A total of 210 burs were selected for the study which were divided in 6 groups of 35(16.66%) each. One (2.8%) bur in negative control group and all burs in positive control group showed contamination. In test groups, 27(77.1%), 29(82.8%), 27(77.1%) and 24(68.5%) burs showed contamination in groups 1, 2, 3 and 4, respectively. There was no association between type of pre-cleaning method with the frequency of contamination (p =0.57). The head of bur was the most frequently contaminated site (p < 0.003). CONCLUSIONS: None of the pre-cleaning method was found to be effective. Head of bur was the most frequently contaminated site.

Frequency of Contamination on Used Healing Abutments after Sterilization: An In Vitro Study.

PURPOSE: To determine and compare the frequency of contamination on different sites of healing abutments (HAs) after sterilization with Phloxine B dye on unused and used HAs after sterilization. MATERIALS AND METHODS: A total of 60 HAs were divided into two test groups: (1) used and sterilized and (2) a control group (unused). The test group was evaluated for contamination after sterilization; the control group did not undergo any procedure. Data were analyzed using SPSS version 22 (IBM). Descriptive statistics were used to determine the frequency of contamination in the different groups and at the different HA sites. Chi-square test was used to evaluate the association of frequency of contamination with the HA site and design. The level of significance was kept at P ≤ .01. RESULTS: The test group showed more contamination compared to the control group. The most contaminated sites were the screw thread and the screwdriver engagement location. CONCLUSIONS: HA reuse is cost-effective, but cleaning and sterilization was not effective for these components; thus, HAs need to be reused with caution because they were heavily contaminated when compared to new HAs. Among the different sites, the screw thread and screwdriver engagement sites were more prone to contamination. HA type did not influence the frequency of contamination.

Exploring the Learning Curve of Dental Implant Placement Using a Task-Autonomous Robotic System Among Young Dentists From Different Specialties-A Pilot Module Study.

BACKGROUND: The learning curve effect of dynamic computer-assisted implant surgery (D-CAIS) was observed among inexperienced novice surgeons. The learning curves can provide valuable information for novice surgeons and valid comparisons between new and conventional techniques. Recently, robotic computer-assisted implant surgery (R-CAIS) has shown promise as a novel dental implant surgical technique for both partially and edentulous patients. However, its learning curve remains unknown. PURPOSE: The aim of this study was to explore the learning curve of dental implant placement surgery with a task-autonomous robotic system among young dentists with different specialties. METHODS AND MATERIALS: Four young dentists (mean age: 25.3 ± 1.5 years at the beginning of their first attempt) with equal representation of males and females and with different specialties participated in this study. None of the participants had prior experience in R-CAIS. Each operator placed eight implants over eight attempts using a semi-active task-autonomous robotic system. Among the eight implants, four were straight lateral incisor implants, and four were 30°-tilted premolar implants. The implants were placed in each dental quadrant of the maxillary and mandibular jaw modules. The operation time was recorded. Coronal, apical, and angular deviations between the planned and actual sites of implant placement were measured by merging preoperative and postoperative cone-beam computed tomography (CBCT) scans. The data were analyzed with repeated-measures ANOVA (α = 0.05). RESULTS: The mean time for implant placement was associated with the number of attempts (p < 0.01). The time taken for the second attempt was significantly shorter than that of the first attempt (33.26 vs. 30.47 min; p < 0.001) then it plateaued. Three-dimensional (3D) angular (p = 0.31), coronal deviation (p = 0.26), and apical deviation (p = 0.06) did not differ significantly among attempts. The mean values and standard deviations of 3D coronal deviation, 3D apical deviation, and 3D angular deviation were 0.71 ± 0.31 mm, 0.72 ± 0.30 mm, and 0.94 ± 0.58°, respectively. Neither the position of the jaw (p > 0.59) nor the tilt angle of the implant (straight or 30°-tilted, p > 0.85) was related to implant placement accuracy. CONCLUSIONS: Dentists quickly learned the basic workflow of R-CAIS and thus facilitated the clinicians in the mastery of implant placement on edentulous jaw modules, leading to a comparable operating speed and high precision. Moreover, the accuracy of placement of straight and tilted implants in both the maxilla and mandible with R-CAIS was satisfactory.

Frequency of Contamination on Used Healing Abutments after Sterilization. An In Vitro Study.

PURPOSE: To determine and compare the frequency of contamination on different sites of healing abutments after sterilization with Phloxine B dye on unused and used healing abutments after sterilization. MATERIALS & METHODS: A total of 60 healing abutments were divided into two test groups: (1) used and sterilized and (2) a control group (unused). The test group was evaluated for contamination after sterilization; the control group did not undergo any procedure. Data were analyzed using SPSS version 22. Descriptive statistics were used to determine the frequency of contamination in the different groups and at the different healing abutment sites. Chi-square test was used to evaluate the association of frequency of contamination with the site and design of the healing abutment. The level of significance was kept at P ≤ .01. RESULTS: The test group showed more contamination compared to the control. The most contaminated sites were the screw thread and the screwdriver engagement location. CONCLUSION: Reuse of healing abutments is cost-effective, but cleaning and sterilization was not effective for these components; thus, healing abutments need to be reused with caution as they were heavily contaminated when compared to new healing abutments. Among the different sites, the screw thread and screwdriver engagement sites were more prone to contamination. Healing abutment type did not influence the frequency of contamination.

Effect of full sulcular versus papilla-sparing flap on periodontal parameters in periradicular surgeries: A systematic review and meta-analysis.

BACKGROUND: Access to apical root canal system is gained after flap elevation using various incision techniques. Soft-tissue healing after periradicular surgery may include gingival recession, papilla recession, changes in probing depth, and clinical attachment loss. OBJECTIVE: The objective of this study was to compare the effect of full sulcular flap design versus papilla-sparing flap design on the periodontal parameters in periradicular surgeries. MATERIALS AND METHODS: It was a systematic review and meta-analysis. Electronic and manual searches were conducted in multiple databases including PubMed, Dental and Oral Sciences, Cochrane, and CINAHL Plus until May 2019. Initial search yielded 2575 studies with 5 articles meeting the inclusion criteria. The primary outcomes assessed were gingival recession and change in the papilla height. The secondary outcomes evaluated were probing depth, clinical attachment loss, postoperative pain, bleeding, and discomfort. Random-effects model was employed for computation of effect size, and forest plots were made. RESULTS: Out of the five articles that satisfied the inclusion criteria, three were randomized control trials and two were nonrandom trials. No significant differences were found in the gingival recession (P = 0.79), papilla height (P = 0.55), gingival bleeding, and plaque indices. Statistically significant differences in probing depth (P = 0.006) and clinical attachment loss (P = 0.0004) were observed for the two flap designs in probing depth (P = 0.006) and clinical attachment loss (P = 0.0004). CONCLUSIONS: The present systematic review and meta-analysis showed that probing depth and attachment loss are affected by the choice of flap design. On the other hand, gingival recession and papilla height are not influenced by the type of incision. However, finding of the present review may change if more studies on this topic will be included in the future. Therefore, more clinical trials with long-term follow-ups are needed.

A Variant of the Current Dens Invaginatus Classification.

Endodontic treatment of maxillary incisors may be considered straight forward. However, in some instances, they may exhibit aberrant morphology. One of these rare variations in tooth morphology is dens invaginatus. To improve the endodontic prognosis of such teeth, a detailed evaluation of the tooth under treatment is important, which requires comprehensive clinical and radiographic examinations, including periapical radiography and cone-beam computed tomography (CBCT), which is highly recommended whenever atypical root canal morphology is suspected on a periapical radiograph. The current case report discusses the diagnosis of type IV dens invaginatus in a maxillary lateral incisor using CBCT.

Decalcification and bond failure rate in resin modified glass ionomer cement versus conventional composite for orthodontic bonding: A systematic review & meta-analysis.

BACKGROUND: Demineralized white spot lesions (DWSLs) are one of the unfavourable effects of orthodontic treatment. Resin modified glass ionomer cement (RMGIC) was introduced to reduce its occurrence. OBJECTIVE: The study aimed to determine the incidence of DWSLs as primary objective and bond failure rate in brackets bonded with RMGIC versus conventional composite (CC) as secondary objective. MATERIAL AND METHODS: A thorough literature search was done until April 2019 on various databases including Scopus, Web of Science, PubMed, Cochrane database, CINHAL, Dental and Oral Science, and manual search. Only human clinical trials and published in English language were included. We considered the experimental group of orthodontic patients with brackets bonded with RMGIC and the control group with brackets bonded with CC. Blind and induplicate study selection, data extraction, and risk of bias assessment were undertaken. RevMan software was used for data analysis. Odds ratio with 95% confidence intervals (CIs) was used to express the effect estimate of frequency of bracket failure bonded using RMGIC and CC. The risk of bias was assessed using Cochrane risk of bias tool for RCTs and ROBINS-I tool for N-RCTs. Sensitivity analyses and subgroup analysis were performed as well. RESULTS: Out of 2285 articles, nine met the inclusion criteria. Five were RCTs and four were N-RCTs. Out of nine, seven studies were included in the meta-analysis. A random effect model was used. No significant difference was found in the bond failure rate (risk ratio: 1.48; 95% CI: 0.57-3.87; P≤0.42). No difference was found in the occurrence of DWSLs between the two groups. CONCLUSIONS: Due to the limited number of studies and studies with high risk of bias, no strong conclusion can be drawn. More studies need to be done to reasonably conclude that RMGIC is beneficial in reducing the occurrence of DWSLs and have comparable bond failure rate. The protocol was registered on PROSPERO (CRD42019125386) prior to the commencement of the systematic review.

Role of three-dimensional printing in periodontal regeneration and repair: Literature review.

Three-dimensional (3D) printing is the process of building 3D objects by additive manufacturing approach. It is being used in endodontics, periodontology, maxillofacial surgery, prosthodontics, orthodontics, and restorative dentistry, but our review article is focused on periodontal application. A detailed literature search was done on PubMed/Medline and Google Scholar using various key terms. A total of 45 articles were included in this study. Most of the studies were in vitro, preclinical, case reports, retrospective, and prospective studies. Few clinical trials have also been done. Periodontal applications included education models, scaffolds, socket preservation, and sinus and bone augmentation and guided implant placement. It showed better alveolar ridge preservation, better regenerative capabilities, greater reduction in pocket depth and bony fill, ease of implant placement in complex cases with greater precision and reduced time with improved outcome and an important tool for education and training using simulated models.

Most effective method for the management of physiologic gingival hyperpigmentation: A systematic review and meta-analysis.

BACKGROUND AND AIM: Gingival hyperpigmentation is an esthetic problem. The aim of the present study was to identify most effective treatment modality for managing generalized physiological gingival pigmentation. MATERIALS AND METHODS: A systematic review and meta-analysis were done (1919 to October 2018) using PubMed, CINHAL, Dental and Oral Science, and manual searches. Twenty-five articles were finally reviewed. Only human clinical trials were considered with physiological gingival pigmentation treated with different depigmentation methods and compared with surgical stripping. The outcome was the achievement of gingival depigmentation and its recurrence. RevMan software was used for data analysis. RESULTS: Of 26,132 articles, 25 met the inclusion criteria. Seventeen were randomized control trials and 8 were nonrandomized control trials. Most of the studies were on laser. The control group was scalpel surgery. Majority of studies showed no difference in compared treatment modality. A meta-analysis compared laser ablation with surgical stripping revealed a nonsignificance difference regarding recurrence (P = 0.75) and depigmentation (P = 0.23) and a statistically significant difference regarding postoperative pain favoring laser ablation (P ≤ 0.05). CONCLUSIONS: Surgical stripping has been the conventional treatment of choice, but our review showed that new techniques are equally effective or even better. Laser especially diode laser was the most frequently used technique and showed better esthetic outcomes, less pain, faster healing, and patients' preference and satisfaction after treatment. However, laser showed more regimentation at 6-month evaluation. More good quality randomized controlled trials with different depigmentation methods are needed to draw strong conclusions.

Visual And Microscopic Evaluation Of The Surface Alterations In The Protaper Files After Single Clinical Use.

BACKGROUND: Different studies have been conducted in which defects of Ni-Ti files were reported after multiple usages but limited data is available regarding the defects in the rotary Ni-Ti files subjected to single clinical use. The objective of this study was to determine the frequency of surface defects caused by fatigue in the rotary ProTaper files after single clinical use assessed with visual and microscopic examination methods. METHODS: A cross-sectional study was conducted in the dental clinics of The Aga Khan University Hospital, Karachi, Pakistan. A total of 189 ProTaper Ni-Ti files (after single clinical use in multi-rooted molars) were analysed visually and then under stereomicroscope at 10Χ magnification for surface defects (straightening, denting, bending, twisting, pitting and change in length). Chi Square test was used to determine association between type of file and type of defect. Spearman's correlation test was used for determination of correlation between visual and microscopic examinations at 0.05 level of significance. RESULTS: 19% of files showed straightening on visual assessment as compared to 66.1% under microscopic examination. There was a statistically significant association between the file type and the straightening of file (p-value ≤0.001). A weak correlation existed between visual and microscopic examination for all the defects, except for the change in length. CONCLUSIONS: The defects of ProTapers files are best detected by the microscopic examination. Straightening is the most common defect observed visually and microscopically. The first shaping and first finishing files underwent significantly more surface defects than the rest of the rotary files in the series.