Post-endodontic pain in curved canals prepared with different rotary instrumentation techniques: A randomized controlled trial.

BACKGROUND: Curved root canals are associated with the highest number of procedural errors during endodontic instrumentation. Recently, numerous rotary instruments have been developed, with both manual and automated mechanisms, to facilitate endodontic treatment and manage the complications related to it. OBJECTIVES: The aim of the study was to assess post-endodontic pain after using the HyFlex® EDM OneFile (HEDM), WaveOne® Gold (WOG) and XP-endo® Shaper (XPS) systems in the preparation of curved canals in patients with asymptomatic irreversible pulpitis. MATERIAL AND METHODS: A total of 45 molars with curved canals and asymptomatic irreversible pulpitis were randomly divided into 3 equal groups based on the instrumentation used: HEDM (group A); WOG (group B); and XPS (group C). All teeth were prepared according to the manufacturers' instructions. Postendodontic pain was assessed using the visual analog scale (VAS) at 6, 12, 18, 24, 48, and 72 h after root canal instrumentation. The data was analyzed using the one-way analysis of variance (ANOVA) and the paired-samples t test with the Bonferroni correction, with a p-value of 0.05 set for statistical significance. RESULTS: The highest levels of post-endodontic pain were recorded at 6 h after treatment. Then, the values gradually decreased until the pain nearly vanished after 72 h. No statistically significant differences were observed in the VAS scores between groups A and B. At the same time, group C showed the lowest VAS scores at all follow-up time points. CONCLUSIONS: The use of the XPS system resulted in the lowest pain scores at all follow-ups. The HEDM and WOG groups showed no differences in the pain scores throughout the whole follow-up period.

A retrospective study on iRoot BP Plus full pulpotomy for primary molars with partial irreversible pulpitis.

OBJECTIVES: This study aimed to observe the outcomes of iRoot BP Plus full pulpotomy in primary molars with partial irreversible pulpitis retrospectively. METHODS: Collect 102 cases of primary molars with partial irreversible pulpitis undergoing iRoot BP Plus full pulpotomy from January 2019 to August 2023, with a follow-up period of 24-47 months. Based on the presence of irreversible pulpitis symptoms before surgery, the included cases will be divided into asymptomatic group (n=53) and symptomatic group (n=49). Observe the clinical and imaging success rates of both groups. RESULTS: Clinical success rates were 96.2% and 97.9% in asymptomatic and symptomatic groups, and radiographic success rates were 96.2% and 93.9% respectively. CONCLUSIONS: iRoot BP Plus full pulpotomy can be used for the treatment of primary molars with partial irreversible pulpitis under an enhanced pulpotomy protocol.

Successful Healing of Periapical Pathology with Partial Pulpotomy in a Mature Permanent Molar: A Case Report.

BACKGROUND Vital pulp therapy approaches are preferred over non-surgical root canal treatment, giving the advantage of preserving the vitality of the dental pulp and thus maintaining its benefits. Such approaches can be performed in teeth having normal apical area; however, performing vital pulp therapy approaches in teeth associated with periapical pathology remains controversial. CASE REPORT We present a case of a mature mandibular right first permanent molar tooth in a medically fit 10-year-old female diagnosed as asymptomatic irreversible pulpitis with asymptomatic apical periodontitis with periapical radiolucency having a periapical index (PAI) score of 4. Partial pulpotomy was performed instead of non-surgical root canal treatment due to uncooperativeness of the patient. Biodentine was used as a pulp capping material. The tooth was restored with resin composite permanent restoration. Six months after the procedure, an intraoral periapical radiograph revealed normal bone features with complete periapical pathology healing and development of intact lamina dura around the mesial and distal roots. The tooth responded normal to electric pulp testing (EPT), cold, percussion, and palpation tests. CONCLUSIONS Periapical pathology involvement having large periapical radiolucency exhibiting PAI score 4 in inflamed dental pulp tooth diagnosed as irreversible pulpitis does not necessitate non-surgical root canal treatment. Partial pulpotomy should be considered as an alternative treatment to promote the return dental pulp and periapical tissue to a healthy condition. Considering a similar approach in older patients would be interesting to gain a more comprehensive understanding of its potential as a treatment method.

Biometric analysis of furcation area of molar teeth and its relationship with instrumentation.

The anatomy of furcation favours the bacterial retention and makes periodontal debridement as well as oral hygiene procedures difficult. Teeth that have lost attachment to a level of the furcation are said to have a furcal invasion or furcation involved.Involvement of furcation in a multi-rooted tooth poses a very different type of clinical situation in terms of establishment of diagnosis, determination of prognosis and of course planning the treatment modality.The present study was carried out on 200 selected extracted human first and second permanent molar teeth based on a predefined criteria. Teeth with prosthetic crowns, fused or fractured roots, those not fully developed, grossly carious or heavily restored at the cementoenamel junction (CEJ) were excluded from the study. The morphology of the root trunk was recorded by measuring various dimensions of the root trunk,including furcal angle and root trunk volume was calculated by using a custom made special apparatus. The furcation areas were debrided with different types of curettes in the market in order to see how best the instrument could be maneuvered in the furcation area. The data so obtained was statistically analysed using SPSS version 22. The highest root trunk volume and the longest root trunk length were found to be in the maxillary second molar. 48.60% furcations didn't allow instrument engagementof furcation area with standard area specific curettes. The proposal of inclusion of root trunk length (mm) is suggested in addition to classification of FI to have assess prognosis and appropriate treatment for of the involved tooth.

Evaluation of Regenerative Efficacy of Amnion and Chorion Membrane in Treatment of Mandibular Molar Furcation Defects: A Clinico-radiographic Study.

AIM: Amnion and chorion membranes possess unique inherited biological properties that enhance wound healing and may accelerate periodontal regeneration. The present study aims to evaluate and compare the efficacy of amnion and chorion membranes in the treatment of furcation defects. MATERIALS AND METHODS: A total of 20 patients were selected and were randomly allocated to group I and group II with 10 subjects in each group. Amnion and chorion membranes are placental-derived membranes that accelerate regeneration by having natural growth factors with their antimicrobial and inflammation reduction properties. Group I was treated using bone grafting with decalcified freeze-dried bone allograft (DFDBA) and placement of amnion as a membrane for guided tissue regeneration (GTR) whereas group II was treated using bone grafting with DFDBA and placement of chorion as a membrane for GTR. The patients were followed for clinical and radiographic parameters and were evaluated between 3 and 6 months after surgery. RESULT: In intragroup comparison, a significant difference was evident in both the groups for all the clinical and radiographic parameters within the groups. (p = 0.01) This means both amnion and chorion membranes showed statistically significant regenerative efficacy. In intergroup comparison, the results show that all the clinical parameters and radiographic parameters show no significant difference between the groups. CONCLUSION: The amnion and chorion membranes had similar regenerative efficacy in combination with DFDBA in patients with buccal degree II furcation defects in mandibular molars. CLINICAL SIGNIFICANCE: The amnion and chorion membranes have shown significant improvement in clinical and radiographic parameters when used for the treatment of buccal degree II furcation defects in mandibular molars. How to cite this article: Mallapragda S, Gupta R, Gupta S, et al. Evaluation of Regenerative Efficacy of Amnion and Chorion Membrane in Treatment of Mandibular Molar Furcation Defects: A Clinico-radiographic Study. J Contemp Dent Pract 2024;25(2):160-167.

Comparative evaluation of volumetric changes between two pediatric rotary files (Kedo-S plus, Kedo-SG blue) and manual files (hand K-files) during canal preparation of primary mandibular molars: an in-vitro nano-CT analysis.

Pediatric endodontics has become popular due to advancements in cleaning, shaping and irrigation systems, resulting in faster and effective removal of infected pulp, saving time, and creating a pathogen-free environment. The patented rotary file system, Kedo-S, designed for primary teeth, introduced a single file generation for efficient pulp therapy. However, there are currently no studies assessing canal preparation in primary mandibular molars using nano-CT (computed Tomography). To evaluate the volumetric changes of two recently introduced pediatric rotary file systems in comparison with conventional hand file systems in primary mandibular molar using an ultra-high resolution nano-CT. This in-vitro study was performed in extracted primary mandibular molar based on certain inclusion and exclusion criteria. Samples were prepared and working length was determined before the pre-operative scan using a high resolution nano-CT device (SkyScan 2214, Bruker, Kontich, Belgium). A single well-experienced pediatric dentist prepared the canals using three file systems: Kedo-S plus, Kedo-SG blue and Hand K-files. A post-operative scan was performed similar to pre-operative scan. Image reconstruction was performed with NRecon software for 3D volumetric visualization and analysis of the root canals. Kedo-SG blue file systems had the highest mean difference in the canal volume (8.85%). Hand K-files had the least difference at (1.24%) of canal volume. Kedo-S plus file system had a mean canal volume difference (6.14%) which is closer to hand K-files. Rotary file systems resulted in a significant enlargement of canals compared to hand files.

Effect of low-level laser therapy in wound healing of primary molar teeth extraction.

INTRODUCTION: Tooth extraction in children requires attention to wound healing and pain management, which are influenced by patient-related factors and behavioral guidance. AIM OF THE STUDY: The study aimed to evaluate the effect of LLLT on healing sockets in pediatric patients with bilateral primary molar teeth extraction and determine its impact on pain management. METHODS: 6-10 years of age, systemically healthy, and with atraumatic extraction indications of bilateral primary molar teeth were included in the study (n = 40). In the first session, randomly selected teeth were extracted under local anesthesia. In the control group, only clot formation in the socket was observed and photographed. The other group extractions were performed 2 weeks later. The low-level laser therapy (LLLT) group was treated with a 980 nm wavelength, in a continuous emission mode, 0.5 W power, 300 J of energy, 400 µm tip, 60 s diode laser and photographed. Nonepithelialized surface measurements were performed using ImageJ. Pain assessment was performed using the Wong-Baker Pain Scale. Statistical analyses were performed using SPSS software. RESULTS: There was a statistically significant difference between the groups in the Wong-Baker values in 3rd day (p < 0.05). In soft tissue healing on the 3rd and 7th day, the nonepithelialized surface of the laser socket was smaller than that of the control group, and the measurement results were found to be statistically significant (p < 0.05). CONCLUSION: Although LLLT was not found to be very effective in reducing postoperative discomfort after extraction of primary molars, it provided better wound healing in extraction sockets.

[A prospective cohort study on the effect of implant restoration following micro crestal flap-alveolar ridge preservation at molar extraction sockets with severe periodontitis].

Objective: To evaluate the survival rate, success rate, soft tissue conditions and marginal bone level changes of implants following micro crestal flap-alveolar ridge preservation at molar extraction sockets with severe periodontitis, compared to natural healing. Methods: From March 2015 to January 2017, patients scheduled for molar extraction as a consequence of severe periodontitis and planned implant-retained prostheses from Department of Periodontology Peking University School and Hospital of Stomatology were selected. A total of 40 molar extraction sockets from 40 patients received implant placement following micro crestal flap-alveolar ridge preservation or natural healing. The front consecutive 20 teeth were assigned to the natural healing group, and the back ones were assigned to the micro crestal flap-alveolar ridge preservation (MCF-ARP) group. The superstructures were placed 6 months later. Within 2 weeks (baseline) and 1, 2 and 3 years after implant crown restoration, modified plaque index, probing depth, modified bleeding index and keratinized tissue width were recorded every six months. Parallel periapical radiographs were taken to evaluate the peri-implant marginal bone level and to calculate marginal bone loss. Independent sample t test or Mann-Whitney U test were used to compare the differences in the above clinical and imaging indicators between the two groups. Results: The implant survival rate and success rate of the two groups were both 100% (20/20). There were no significant differences in the modified plaque index, probing depth, modified bleeding index, buccal keratinized tissue width and marginal bone loss between two groups at 1, 2 and 3 years after implant crown restoration (all P>0.05). Marginal bone loss was 0.22 (0.14, 0.34) mm in the natural healing group and 0.21 (0.12, 0.30) mm in the MCF-ARP group at a 3-year post-loading evaluation. Conclusions: Within the limitations of the present study, implants placed at ridge preserved and naturally healed molar extraction sockets with severe periodontitis demonstrate comparable clinical outcomes at a 3-year post-loading evaluation.

Unexpected sequel to the application of silver fluoride followed by stannous fluoride to an open carious lesion in a primary molar: A case report.

OBJECTIVES: The use of silver fluoride followed by stannous fluoride was designed for the treatment of open carious lesions in primary molars in dental outreach programs. However, during the COVID-19 pandemic when aerosol-producing procedures were inadvisable, one dental location started using it as the first stage in a two-visit restorative procedure for carious primary molars. If the gap between the fluoride application and the restoration placement stages was around 3-5 weeks it was noticed that a black friable crust appeared on the caries surface. To investigate further a normally discarded crust from one patient was retrieved and sent for analysis. MATERIALS AND METHODS: Two techniques suitable for identification and preliminary analysis of material of unknown composition, scanning electron microscopy and energy dispersive spectroscopy (EDS) were used. The only preparation was that the specimen was dried and coated beforehand. RESULTS AND CONCLUSIONS: This preliminary examination showed two unexpected findings. The first was that the crust surface indicated a possible dentine derivation as it was covered with reasonably evenly spaced holes. In addition, the EDS spectrum showed it to be, at least, partially mineralized. The second unexpected finding was that the surface was coated with electron-dense particles. The size of the particles and the EDS spectrum pointed to the likelihood of the majority of them being nanosilver. These unexpected findings suggest a possible new direction for research.

Comparative evaluation of hand and rotary file systems on dentinal microcrack formation during pulpectomy procedure in primary teeth: an in vitro study.

PURPOSE: Pulpectomy can be used for the management of deep dentinal carious lesions in primary teeth which can be restored. Mechanical preparation of root canals can be performed using hand or NiTi rotary files. However, this may cause dentinal stress and consequently dentinal microcracks. Hence, the aim was comparative evaluation of hand and rotary file systems on dentinal microcrack formation during pulpectomy procedure in primary teeth. METHODS: 60 extracted primary molar teeth were selected comprising of 80 root canals. Simple random sampling was used to divide root canals into four groups (n = 20): Group A-Hedstrom file, Group B-Pro AF Baby Gold rotary, Group C-ProTaper Next rotary, and Group D-unprepared group. Assessment was conducted on presence or absence of microcracks using Chi square test (p < 0.05). RESULTS: The total number of microcracks in Group A: one (5%), Group B: four (20%), Group C: nine (45%) and Group D: zero (0%) which was statistically significant (p = 0.002). At cervical third, the number of microcracks seen with Group A: one (5%), Group B: zero (0%), Group C: five (25%) and Group D: zero (0%) (p = 0.005). At the middle third, the number of microcracks seen in Group A: zero (0%), Group B: four (20%), Group C: four (20%) and Group D: zero (0%) (p = 0.029). CONCLUSION: The study concluded that dentinal microcracks are formed with both hand and rotary file systems in primary teeth. ProTaper Next showed significantly higher number of microcracks, followed by ProAF Baby Gold and H files.

Comparative evaluation of cervical pulpotomy and pulpectomy for primary molars with irreversible pulpitis: a multicentre randomised controlled trial.

PURPOSE: The objective of this multicentre randomised controlled trial was to compare the clinical/radiographic outcomes of cervical pulpotomy using calcium-enriched mixture cement (PCEM) and pulpectomy using Metapex (PM) in primary molars with irreversible pulpitis (IP). METHODS: A total of 134 primary molars from 94 children were randomly assigned to two intervention groups: the PCEM group (n = 74) and the PM group (n = 60). Baseline characteristics including age/gender/molar type/tooth type/jaw were recorded. The primary outcome measures were clinical/radiographic success rates assessed at the first and second follow-up appointments. Secondary outcomes included reasons for clinical/radiographic failures. Multiple logistic regression analysis was performed to determine the impact of various factors on the success rates. RESULTS: The mean age of the participants in both groups was similar (PCEM group: 5.4 years, PM group: 5.5 years). Gender distribution, molar type, tooth type, jaw, and number of practitioners were comparable between the groups. The clinical success rate at the first follow-up was 98.6% in the PCEM group and 96.4% in the PM group. At the second follow-up, the clinical success rate was 97.1% in the PCEM group and 91.1% in the PM group. The radiographic success rates at the first and second follow-up were 98.6% and 96.4% in the PCEM group and 96.4% and 91.1% in the PM group, respectively. Multiple logistic regression analysis did not reveal any significant association between the success rates and age/gender/molar type/jaw, or treatment groups (P > 0.05). CONCLUSION: In primary molars with IP, both simple/conservative cervical pulpotomy using calcium-enriched mixture cement and pulpectomy using Metapex demonstrated high clinical/radiographic success rates. No significant differences were observed between the two treatment modalities. These findings suggest that both techniques can be considered effective treatment options for managing primary molars with IP. TRIAL REGISTRATION NUMBER: Trial registration number: IRCT20201226049838N1, retrospectively registered on 12 January 2021.

Micro-computed tomographic evaluation of the shaping ability of three nickel-titanium rotary systems in the middle mesial canal of mandibular first molars: an ex vivo study based on 3D printed tooth replicas.

BACKGROUND: The preparation of the middle mesial (MM) canal of mandibular molars represents a challenge because it is often curved, narrow, and close to the root concave. The purpose of this study was to evaluate the ex vivo shaping ability of 3 nickel-titanium (NiTi) rotary systems in the MM canal using 3D printed resin tooth replicas. METHODS: A permanent mandibular first molar with a MM canal was acquired from a pool of extracted teeth and reproduced by a 3D printer. The resin tooth replicas (n = 18) were equally assigned to 3 groups for the evaluation of the shaping abilities of 3 NiTi rotary systems (OneShape [OS], Twisted Files [TF], and ProTaper Gold [PTG]) according to the manufacturer's recommendations. The tooth replicas were scanned by micro-computed tomography (micro-CT) twice before and after instrumentation of the mesiobuccal (MB), mesiolingual (ML), and MM root canals. After 3D reconstruction, the canal straightening, change of root canal volume and surface area, the mesial and distal canal wall thickness and canal transportation at the levels of 1, 2, and 3 mm below furcation were assessed. One-way variance analysis and Turkey's post hoc test were used for comparisons of the means among different groups, and paired-t test was used to compare the mesial and distal sides of the mesial roots. RESULTS: As compared with OS and TF, the use of PTG in preparation of MM canals resulted in significantly more straightening of canal curvature (p < 0.05), greater post-instrumentation canal volume and surface area, and thinner mesial and distal remaining canal wall thickness at 1, 2 and 3 mm below furcation (all p < 0.05). Regarding the root canal transportation in the mesiodistal direction, there was no significant difference among the 3 instruments (all p > 0.05) after the preparation of the MB and ML canals. However, in the MM canal, more pronounced transportation was detected in the PTG group at 2 mm below furcation, and in the TF group at 3 mm below furcation as compared with the other 2 systems (both p < 0.05). CONCLUSIONS: 3D printed tooth replicas have the advantages of consistency and can be an ideal model to evaluate the shaping ability of different instruments in the MM canal. OS and TF files performed similarly and both are appropriate for shaping the MM canal, while PTG may cause excessive and uneven resin removal, especially near the furcation, and may lead to root fragility and procedural errors.

Clinical and electromyographic signals analysis about the effect of space-adjustment splint on overerupted maxillary molars.

BACKGROUND: Overerupted maxillary molars is common in adults, which can lead to insufficient intermaxillary vertical space ,great difficulty in prosthetic reconstruction ,and cause occlusal interference in movements.To reconstruct occlusal function, it is necessary to prepare enough space for prostheses. The aim of the present study was to evaluate the effect of space-adjustment occlusal splint on overerupted maxillary molars by clinical and electromyographic signals analysis. METHODS: Eighteen patients with overerupted maxillary molars were selected to wear space-adjustment occlusal splint suppressing overerupted maxillary molars for three months. Satisfaction was assessed by 5-point Likert; intermaxillary vertical space and the teeth transportation distance were measured in models; clinical periodontal status were evaluated by periodontal probing depth (PPT) and bleeding index (BI); electromyographic recordings of the masseter and anterior temporal muscles were monitored by Cranio-Mandibular K7 Evaluation System. RESULTS: All the patients were satisfied with the treatment effect (Likert scale ≧ 4). The intermaxillary space in edentulous areas after treatment showed statistically significant increasing when compared with those before treatment. PPT and BI showed no significant difference. No statistically significant differences were found in electromyographic activity of anterior temporal muscles, while a reduction of muscle activity in masseter in the contralateral side were detected in post-treatment evaluations compared with pre-treatment at mandibular rest position. CONCLUSIONS: Space-adjustment occlusal splint is an efficient treatment option on overerupted maxillary molars by intruding the maxillary molar to obtain adequate intermaxillary space for prostheses.

Vital root resection with radicular retrograde partial pulpotomy in furcation-involved maxillary molars in patients with periodontitis: Technique description and case series considering clinical and economic aspects.

AIM: Conventional root resection in periodontally compromised furcation-involved maxillary molars requires preceding endodontic treatment and is therefore associated with loss of tooth vitality, higher invasiveness, treatment time and costs, and the risk of endodontic complications. Vital root resection (VRR) could overcome these disadvantages while establishing stable periodontal and endodontic conditions. This case series aimed to introduce the concept of one-stage VRR with radicular retrograde partial pulpotomy (VRRretro). SUMMARY: Seven vital maxillary molars with residual probing pocket depths (PPD) ≥ 6 mm and furcation ≥ class 2 of five patients with stage III/IV periodontitis were treated with VRRretro using mineral trioxide aggregate. Teeth with residual through-and-through furcations were additionally tunnelled. Follow-up up to 2.5 years postoperatively during supportive periodontal care included full periodontal status, percussion and thermal sensitivity testing. Periapical radiographs were obtained to rule out possible periradicular radiolucencies. All seven treated molars were in-situ at an average of 26.84 ± 5.37 months postoperatively and were clinically and radiographically inconspicuous independent of tooth position, the resected root, the need for tunnelling and the restorative status. The mean PPD on the seven treated molars was 4.02 ± 0.85 mm (6-10 mm) preoperatively and 2.62 ± 0.42 mm (3-4 mm) at the last follow-up. Clinical attachment level and bleeding on probing could also be decreased. The teeth showed no mobility over time and furcations class 2 were reduced to class 1 while the tunnelled furcations were accessible with interdental brushes. All molars reacted negatively to percussion and positively to thermal sensitivity testing. KEY LEARNING POINTS: In carefully selected cases considering patient- and tooth-related factors, VRRretro could be a promising treatment option to establish stable periodontal and endodontic conditions in furcation-involved maxillary molars while preserving tooth vitality.

[Root resection: tooth preservation by targeting the root of the problem]. / Wortelresectie: tandbehoud door problemen bij de wortel aan te pakken.

When problems occur in multirooted teeth, such as persistent endodontic problems following endodontic treatment, problems involving fracture or furcation, extraction may be decided on. However, removal of the tooth will result in loss of occlusal units and the alveolar process. By removing the compromised root and preserving the healthy part, the tooth can remain functional, but only after restorative treatment. A correct indication or diagnosis, a properly performed endodontic, restorative and surgical treatment and proper follow-up are mandatory for a successful treatment outcome.

Is it possible to extract primary maxillary molars without palatal injection?: a controlled clinical trial.

OBJECTIVES: The absolute necessity of a palatal injection for the extraction of primary maxillary molars has never been explored, despite the fact that it is widely known that children do not tolerate local anesthetic injections into the palatal tissue well. The aim of this study was to compare separately the perception of pain in the absence of palatal injection after anesthesia and maxillary primary molar tooth extraction using different anesthetic solutions and different post-anesthetic waiting times. MATERIALS AND METHODS: A single-blinded randomized controlled study was conducted in 78 participants (26 patients with palatal anesthesia (the control groups), and 26 patients with 5 min and 26 patients with 8 min post-anesthetic waiting time without palatal anesthesia (the study groups)). Subjective experiences of pain were evaluated separately after anesthesia and tooth extraction using the Visual Analog Scale (VAS) and the Wong-Baker Faces Pain Rating Scale (WBS). RESULTS: In terms of VAS scores obtained following administration of anesthesia, there was a statistically significant difference between the groups (p<0.05). VAS pain scores were reported to be lower in the groups without palatal anesthesia than in the groups with palatal anesthesia. No statistically significant difference was observed in VAS and Wong-Baker scores after tooth extraction between the groups with and without palatal anesthesia (P>0.05). CONCLUSIONS: While the pain reported following administration of anesthesia was found to be higher in the groups receiving palatal anesthesia, no difference was found between the groups in the pain reported after tooth extraction. CLINICAL RELEVANCE: Extraction of maxillary primary molars is possible without palatal injection by injecting 4% articaine or 2% lidocaine into the buccal vestibule of the tooth with a waiting time of 5 or 8 min.

Rat Peri-implantitis Models: A Systematic Review and Meta-analysis.

PURPOSE: To review experimental peri-implantitis studies using rat models and summarize different peri-implantitis induction techniques and evaluate their effectiveness. MATERIALS AND METHODS: Electronic searches were conducted by two independent examiners to address the following issues. Meta-analyses explored the marginal bone loss (MBL) of four types of peri-implantitis induction methods in rats. The detailed induction tactics-such as the implant design, implant size, surgical process, time cost, induction methods, and endpoint measurements-were summarized. RESULTS: Of the 18 included studies, 38.9% of the studies placed implants at the maxillary first molar, and 44.4% placed them at the alveolar ridge region anterior to the maxillary first molar. As for the induction method, the numbers of published studies on ligature methods, bacterial inoculation, and bacterial lipopolysaccharide inoculation were equally high among all selected studies. The total implant survival rate at the end was 160 out of 213 implants (75.11%). Eight studies with high pooled heterogeneity (I2 = 98, P < .01) in the meta-analysis reported an overall MBL (µ-CT) of 0.47 mm (95% CI = 0.14 to 0.81). A subgroup analysis estimated an MBL of 0.31 mm (95% CI = 0.12 to 0.50) for bacterial inoculation and 0.66 mm (95% CI = 0.07 to 1.26) for the ligature method. Histopathologic analysis revealed that peri-implantitis in rats was similar to peri-implantitis lesions in humans. CONCLUSIONS: Implant placement at the maxillary first molar with bacterial inoculation and the silk ligature method to build peri-implantitis rat models is reliable to use for research on peri-implantitis.

Spontaneous space closure in patients treated with early extraction of the first permanent molar: a retrospective cohort study using radiographs.

OBJECTIVES: To assess the success rate of spontaneous space closure after extraction of the first permanent molar (FPM) in the maxilla and the mandible, and to identify the factors that make spontaneous space closure most favorable in each. MATERIALS AND METHODS: A retrospective records-based cohort study was conducted through a search of the database of the Public Dental Service, Stockholm County Council, Stockholm, for young adults born between 2000 and 2001, who underwent extraction of one or more FPM between 2006 and 2016. A total of 995 extracted teeth were identified, of which 203 teeth in 155 patients met the inclusion criteria. RESULTS: Of the 203 extracted teeth, 166 (81.8%) did not receive any orthodontic treatment. The success rate for space closure in orthodontically treated patients was 91.9%. The success rate for spontaneous space closure was 84.3%. All unsuccessful spontaneous space closure in the maxilla occurred in patients older than 12 years. The dental developmental stage of the second permanent molar (SPM) had a statistically significant association with spontaneous space closure in the mandible (P < .001). CONCLUSIONS: The success rate of spontaneous space closure was high (84.3%) and was higher in the maxilla (94.1%) than the mandible (74.1%). Age at time of extraction and dental developmental stage of the SPM were significant factors for successful spontaneous space closure in the maxilla and mandible, respectively.

Effect of preemptive use of a nonsteroidal anti-inflammatory drug and a corticosteroid on the efficacy of inferior alveolar nerve blockade and postoperative pain control in endodontic treatment of molars with symptomatic pulpitis: A randomized double-blind placebo-controlled clinical trial.

AIM: The anaesthetic success rate of an inferior alveolar nerve block (IANB) in mandibular molars with irreversible symptomatic pulpitis can be low, and postoperative pain control in teeth with this diagnosis can be challenging. This study aimed to evaluate the influence of preemptive use of dexamethasone and oral potassium diclofenac on the success of IANB. The influence of these drugs on the intensity of postoperative pain was assessed as a secondary outcome. METHODOLOGY: Eighty-four patients with mandibular molars diagnosed with irreversible symptomatic pulpitis recorded preoperative pain intensity using a cold thermal test and a modified Numerical Rating Scale (mNRS). Sixty minutes before the anaesthetic procedure, patients were randomly assigned to one of three groups based on the medication they received: dexamethasone (4 mg), diclofenac potassium (50 mg), or placebo. All patients received IANB with 4% articaine (1:200 000 epinephrine), and 15 min later, they were evaluated for pain intensity using the cold thermal test. Anaesthetic success was analysed. The pain intensity was then recorded, and endodontic treatment and provisional restoration of the tooth were executed in a single session. Patients were monitored for 6, 12, 24, 48 and 72 h using the mNRS to assess the intensity of postoperative pain. RESULTS: There was a statistically significant increase in anaesthetic success when 4 mg dexamethasone (39.3%) or 50 mg diclofenac potassium (21.4%) was used compared to the placebo group (3.6%) (p < .001), with no significant difference between the two drugs. Regarding postoperative pain, dexamethasone was superior to placebo at 6 h (p < .001), with diclofenac having an intermediate behaviour, not differing between dexamethasone and placebo (p > .05). There was no significant difference amongst the groups at 12 h (p > .05). At 24, 48 and 72 h, the effectiveness of dexamethasone and diclofenac were comparable, and both were superior to placebo (p < .001). CONCLUSION: The use of dexamethasone or diclofenac potassium was favourable in terms of increasing the success rate of inferior alveolar nerve block in cases of mandibular molars with irreversible symptomatic pulpitis and decreased the occurrence of postoperative pain when compared to the use of a placebo.

One-year radiographic and clinical performance of bioactive materials in primary molar pulpotomy: A randomized controlled trial.

OBJECTIVES: Mineral Trioxide Aggregate (MTA) is considered the gold standard material for pulpotomy procedures. However, some drawbacks such as poor handling and long setting time are challenging when it is used as pulpotomy dressing in primary molars in children. Hence, the purpose of this study was to compare the radiographic and clinical performance of a premixed, fast setting bioceramic root repair material (BC RRM-F) with MTA in vital pulpotomy procedures of primary molars, with or without the added seal of a stainless steel crown (SSC). METHODS: In this double blinded, four-arm, parallel group randomized contolled trial (RCT), 64 primary molars were randomly allocated to one of the four treatment groups: MTA (PDTM MTA WHITE)+SSC, MTA+GI (bulk fill glass ionomer with glass hybrid technology GC EQUIA Forte® HT), BC RRM-F+GI and BC RRM-F+SCC. All molars were evaluated clinically and radiographically according to the modified Zurn and Seale criteria at 1, 3, 6, and 12 months follow up. Multivariate cox regression models and Kaplan-Meier curves were used for survival analysis. RESULTS: There was no statistically significant difference between the success of both pulp capping materials used. Overall survival analysis showed that using GI instead of SCC as a final restorative material was significantly associated with increased risk of failure. CONCLUSIONS: TotalFill® BC RRM™ Fast Set Putty can be used as an alternative to MTA in primary molar pulpotomy. Regardless of the pulp capping material, one year survival of pulpotomized primary molars restored with SSC is higher compared to those restored with GC EQUIA Forte® HT. CLINICAL SIGNIFICANCE: Clinicians' preference and cost effectiveness may justify the use of either material in primary molar pulpotomy. Parents insisting on tooth-colored restorations for their children's pulpotomized teeth cannot be told that the expectation for success is the same as those restored with SSC, even if calcium silicate-based pulp capping materials are used.