The Morphology of Peri-Implantitis Bone Defects: A Retrospective Study on Periapical Radiographs.

Objectives: The aims of this study were to assess the morphologic features of peri-implant defects, as measured on 2D intraoral radiographs, and to investigate the possible correlation between such morphology and other parameters related to the position and characteristics of the implant or the implant-supported prosthesis. Materials and Methods: Implants with peri-implantitis were included in this retrospective study. Data collected were related both to the patients and to the position/characteristics of the implants and the implant-supported prosthesis. Measurements of the morphologic defects were performed by two operators on digitalized intraoral periapical radiographs. Results and Conclusion. In total, 73 implants in 27 patients were included. The measurements of the periapical radiograph suggested that the most common defect conformation was crateriform, with both intraosseous and horizontal components. An inverse correlation was found between the extension of the peri-implant lesion and the time between the radiographic assessment and the implant placement. The total lesion area was strongly correlated to oral hygiene levels. No correlations between lesion extension and smoking, diabetes, history of periodontal were found. In conclusion, the results from this 2D radiographic study showed the prevalence of crateriform peri-implant defects, with a hygiene-correlated extension, perceptible on the mesial and distal aspects; 3D imaging could be used when available for further research and clinical investigation.

Erythritol powder airflow for the treatment of peri-implant mucositis: A randomized controlled clinical trial.

OBJECTIVES: Peri-implant mucositis is a biofilm-related, reversible inflammatory disease that can evolve into peri-implantitis if not adequately treated. The aim of the present randomized controlled clinical trial was to evaluate the efficacy of air-abrasive powder as compared to chlorhexidine (CHX) for the treatment of peri-implant mucositis, in terms of clinical and patient-reported outcomes (PROMs) and occurrence of peri-implantitis 12 months after treatment. METHODS: In the control group, full-mouth calculus and plaque removal was performed with ultrasound and manual devices, and a 1.0% CHX gel was applied; in the test group, supra- and subgingival biofilm removal was performed using erythritol powder with a dedicated nozzle and calculus removal was performed with ultrasonic instruments if needed. Bleeding and plaque indexes, peri-implant probing depth and tissue level were measured at 1 week, and 1, 3, 6 and 12 months after treatment, while PROMs were evaluated up to 7 days after treatment. RESULTS: Among 80 included implants, 70 were analysed at 12 months follow-up (30 in the test group, 40 in the control group, and 20 subjects). Success rates (implant-level) in terms of bleeding index were significantly different between the test (96.7%) and control group (92.5%); as for PROMs, only taste sensation was significantly better in the test group. The test group was significantly correlated to the smallest changes in peri-implant probing depth between baseline and 3 months. CONCLUSIONS: The study showed that both treatment strategies are effective. This suggests that the use of air-abrasive powders could be used as an alternative biofilm removal method instead of adjunctive treatments with antiseptics.

The influence of implant position and of prosthetic characteristics on the occurrence of peri-implantitis: a retrospective study on periapical radiographs.

OBJECTIVE: The present retrospective study aimed to investigate the influence of malposition on the occurrence of peri-implantitis. MATERIALS AND METHODS: The study included clinical records of systemically healthy patients with single and partial implant-supported rehabilitations and at least 1-year post-loading follow-up. The parameters collected included implant-related factors, patient-related factors, site-related factors, and prosthesis-related factors. The radiographic measurements were taken by using a dedicated software and the diagnosis of peri-implantitis was made based on all the available clinical and radiographic data. Descriptive statistics were provided for all variables. Following an exploratory approach, an implant-level analysis of factors influencing the occurrence of peri-implantitis was done through a multilevel multivariate logistic regression (mixed). RESULTS: A total of 180 implants belonging to 90 subjects were randomly selected. Malposition showed no statistically significant association with the occurrence of peri-implantitis. According to the multi-level analysis, the parameters that were significantly associated with peri-implantitis included presence / history of periodontitis (OR = 5.945, 95% CI: 1.093 - 32.334, P = 0.039) and presence of an emergence profile angle ≥ 45° (OR = 9.094, 95% CI: 2.017 - 40.995, P = 0.005). CONCLUSIONS: Implant malposition, as defined following Buser's criteria (2004), did not influence the occurrence of peri-implantitis in the selected cohort. Conversely, history of periodontitis and presence of a prosthetic emergence profile with an angle ≥ 45° were correlated to an increased risk of peri-implantitis.

Endodontic Surgery of the Palatal Root of a Maxillary Molar Associated with Simultaneous Management of a Maxillary Sinus Lesion.

This case report describes a particular application of endodontic microsurgery with a palatal approach in the presence of a radiopaque lesion inside the maxillary sinus. The patient presented complaining of pain related to the first maxillary molar and events of nasal obstruction and facial pain in the cheek and nasal area. The endodontic orthograde treatment and retreatment were done, respectively, 7 and 4 years earlier. The cone-beam computed tomography (CBCT) scan taken before the treatment showed two separate lesions: one associated with the palatine root of the molar and another one inside the maxillary sinus. The patient agreed to solve both problems in one surgical step: endodontic surgery of the palatine root with palatal access with the simultaneous asportation of a lesion from the maxillary sinus floor. Complete bone healing of the periapical area and the maxillary sinus was visualized on intra-oral radiographs, and CBCT was taken one year after the treatment. As far as the authors know, no one in literature has ever described this approach and solved in such a conservative way both the problems at the tooth and in the maxillary sinus.

Laser treatments as an adjunct to non-surgical periodontal therapy in subjects with periodontitis and type 2 diabetes mellitus: a systematic review and meta-analysis.

OBJECTIVES: Periodontal disease and diabetes have an extensively investigated bidirectional correlation. Non-surgical periodontal treatment (NSPT) was proven to contribute to glycemic control. Moreover, it may benefit from the association of adjunctive therapies. The aim of the present systematic review is to assess the clinical efficacy of NSPT in association with laser (LT) or photodynamic therapy (PDT) in controlled or uncontrolled diabetic patients, and to grade the level of evidence. MATERIALS AND METHODS: Randomized controlled clinical trials with at least 3-month follow-up were searched in MEDLINE via OVID, EMBASE, and Cochrane Central, screened for inclusion, and grouped based on the performed treatments, follow-up time, type of diabetes, and level of glycemic control. RESULTS: Eleven RCTs with 504 total subjects were included. The adjunct of PDT showed a statistically significant 6-month difference in PD changes (with low certainty of evidence), but not in CAL changes, while a significant difference in 3-month PD and CAL changes was found with the adjunct of LT (low certainty of evidence). Patients treated with PDT registered a higher decrease in HbA1c levels at 3 months, but no significant difference was noted at 6 months; LT also led to better HbA1c changes at 3 months with a moderate certainty of evidence. CONCLUSION: Despite the promising short-term HbA1c decrease, the results should be interpreted with caution due to the small effect sizes and the statistical heterogeneity, and further evidence from well-designed RCTs is needed to support the routine use of PDT or LT in adjunct to NSPT.

Mechanical Resistance of a 2.9-mm-Diameter Dental Implant With a Morse-Taper Implant-Abutment Connection.

Among the complications that can occur at dental implants, the fracture of any implant component is a relatively infrequent but clinically relevant problem. Because of their mechanical characteristics, small diameter implants are at higher risk of such complication. The aim of this laboratory and finite element method (FEM) study was to compare the mechanical behavior of a 2.9- and 3.3-mm-diameter implant with a conical connection under standard static and dynamic conditions, following the International Organization for Standardization (ISO) 14801:2017. Finite element analysis was performed to compare the stress distribution on the tested implant systems under a 300-N, 30° inclined force. Static tests were performed with a load cell of 2 kN; the force was applied on the experimental samples at 30° with respect to the implant-abutment axis, with an arm of 5.5 mm. Fatigue tests were performed with decreasing loads, at 2-Hz frequency, until 3 specimens survived without any damage after 2 million cycles. The emergence profile of the abutment resulted the most stressed area in finite element analysis, with a maximum stress of 5829 and 5480 MPa for 2.9- and 3.3-mm-diameter implant complex, respectively. The mean maximum load resulted in 360 N for 2.9-mm-diameter and 370 N for 3.3-mm-diameter implants. The fatigue limit was recorded to be 220 and 240 N, respectively. Despite the more favorable results of 3.3-mm-diameter implants, the difference between the tested implants could be considered clinically negligible. This is probably due to the conical design of the implant-abutment connection, which has been reported to present low stress values in the implant neck region, thus increasing the fracture resistance.

Immediate implant positioning using tooth-derived bone substitute material for alveolar ridge preservation: Preliminary results at 6 months.

OBJECTIVES: In the present study we evaluated the effectiveness of the use of a novel autologous bone substitute derived directly from processing the extracted tooth in the upper premolar area to preserve a suitable esthetic score and functionality. MATERIAL AND METHODS: Fourteen bone-level implants with platform switching were inserted in 12 patients immediately after atraumatic extraction of premolars for restorative or endodontic reasons. The implant buccal bone gap was filled using autologous tooth extracted-derived material. Clinical and radiographic parameters, including Pink Esthetic Score (PES) were evaluated at 6 months. RESULTS: A total of 10 patients accounting for 11 implants were included. PES showed a suitable esthetic result, and all the implant-prosthetic rehabilitation reported full satisfaction for masticatory function, phonetics, and aesthetics. Bone levels were stable and not affected by implant location, lesion type, or bone quality. CONCLUSION: Radiographically the autologous bone substitute used appears stable in the surgical site and there is good continuity between the autologous bone and the graft. No adverse effects such as periodontal inflammation, infection, or graft rejection was reported.

Differentiating Gender and Sex in Dental Research: A Narrative Review.

While in humans the term "sex" refers to the biological attributes that distinguish subjects as male, female, and intersex, the term "gender" refers to psychological, social, and cultural factors that strongly influence attitudes, behaviors, and relationships of individuals. Recently, it has been emphasized how the integration of these two terms in the design of the research can improve the methodology of the research itself. However, in dental research, the influence of gender has not gained enough consideration and it is often used indiscriminately as a synonym for sex. This narrative review discusses the usefulness of considering gender and sex in dental research, whose guidelines have been provided so far on this topic, and whether the top 20 dental scientific journals promote the analysis of sex and gender in their guidelines. Sex and gender analysis in dental research could be important both for analyzing biological differences such as those in the immune or neuro-immune system, cardiovascular physiology, developmental anomalies or deformities, and psychosocial differences such as lifestyle, pain experience and prevalence of chronic pain, eating behavior, and access to healthcare services. As for the specific policies for sex and gender analysis and reporting, only five out of 20 biomedical journals have included them in their editorial policy, which refers mainly to the correct use of the terms "sex" and "gender." In conclusion, we found that no specific and differentiated sex and gender analysis and reporting are required in dental journals. Their integration, which is still not routinely applied, may be improved in the future by updating editorial guidelines and developing more specific methodological recommendations.

Chairside Screening for Undiagnosed Diabetes and Prediabetes in Patients with Periodontitis.

Introduction: Globally, it is estimated that half of all people with diabetes are undiagnosed. Because of the well-documented bidirectional link between diabetes and periodontitis, dentists and dental hygienists may have the possibility to screen a targeted population for diabetes during routine dental visits. The aim of the present study is to investigate the effectiveness of one device for diagnosis of diabetes/prediabetes used in one private dental practice and investigate the correlation between the levels of HbA1c and periodontal parameters. Methods: Periodontal patients that were never diagnosed with diabetes were asked to fill a risk assessment questionnaire for type 2 diabetes mellitus. PD, CAL, FMBS%, FMPS%, and HbA1c through a prick-finger test were measured before and after periodontal therapy or only once in patients following supportive periodontal therapy. Results: A total of 98 subjects were screened, and among them, one had diabetes and 30 had prediabetes. The mean value of HbA1c was 5.62% for patients with untreated periodontitis and 5.42% for periodontally treated patients. The diagnosis of diabetes resulted to be correlated to FMBS% and FMPS%, while HbA1c levels were correlated to FMBS%, FMPS%, and periodontitis grade. Conclusion: The present chairside diabetes-screening protocol allowed a consistent proportion of patients to become aware of their pathological or prepathological condition and to seek proper and timely medical care. Thus, dentists and dental hygienists could provide health promotion services and preventive measures.

The effect of the use of proton pump inhibitors, serotonin uptake inhibitors, antihypertensive, and anti-inflammatory drugs on clinical outcomes of functional dental implants: A retrospective study.

OBJECTIVE: The present retrospective study investigated the effect of chronic intake of proton pump inhibitors, selective serotonin uptake inhibitors, anti-inflammatory, and antihypertensive drugs on the survival of dental implants and on the occurrence of peri-implantitis. MATERIALS AND METHODS: Survival analyses for implant failure and peri-implantitis were performed patient level for each drug subcategory and for risk factors. The HR for each drug was calculated with adjusted models as compared with a control group made of subjects not assuming the specific drug. Multilevel logistic regression was used to explore the influence of implant-level and patient-level variables on the outcomes. RESULTS: A total of 270 subjects receiving 1118 dental implants were included, with a mean follow-up time of 5.19 ± 4.22 years. After 10 years, the survival rate was 86.9% (patient level), and according to survival analysis, 61.3% of subjects were free from peri-implantitis. The use of anti-inflammatory medicines produced a significant effect (p = .04) on peri-implantitis as compared to subjects not using the drug, with a 2.7-year drop in the mean survival time. The HR was slightly above the level of significance in a semiadjusted model (p = .058). The multilevel analysis found a significant effect on the entire sample and not when considering only subjects with implants with more than 1-year follow-up. CONCLUSIONS: We found a possible relationship between anti-inflammatory drug use and the occurrence of peri-implantitis in the examined cohort of patients, and no correlation for the other drugs.

Fungal species in endodontic infections: A systematic review and meta-analysis.

Fungal infections are common on oral mucosae, but their role in other oral sites is ill defined. Over the last few decades, numerous studies have reported the presence of fungi, particularly Candida species in endodontic infections, albeit in relatively small numbers in comparison to its predominant anaerobic bacteriome. Here, we review the fungal biome of primary and secondary endodontic infections, with particular reference to the prevalence and behavior of Candida species. Meta-analysis of the available data from a total of 39 studies fitting the inclusion criteria, indicate the overall weighted mean prevalence (WMP) of fungal species in endodontic infections to be 9.11% (from a cumulative total of 2003 samples), with 9.0% in primary (n = 1341), and 9.3% in secondary infections (n = 662). Nevertheless, WMP for fungi in primary and secondary infections which were 6.3% and 7.5% for culture-based studies, increased to 12.5% and 16.0% in molecular studies, respectively. The most prevalent fungal species was Candida spp. The high heterogeneity in the reported fungal prevalence suggests the need for standardized sampling, and speciation methods. The advent of the new molecular biological analytical platforms, such as the next generation sequencing (NGS), and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF), that enables identification and quantitation of a broad spectrum of hitherto unknown organisms in endodontic infections should radically alter our understanding of the endodontic mycobiome in the future. Candida spp. appear to be co-pathogens with bacteria in approximately one in ten patients with endodontic infections. Hence, clinicians should comprehend the importance and the role of fungi in endodontic infections and be cognizant of the need to eradicate both bacteria and fungi for successful therapy.

The Applications of Enamel Matrix Derivative in Implant Dentistry: A Narrative Review.

Enamel matrix derivative (EMD) has been successfully used for periodontal regeneration in intrabony defects. Recently, its use for peri-implant bone regeneration has also been hypothesized. The aim of this paper is to review preclinical and clinical studies investigating the use of EMD in correspondence with titanium implants, alone or as an adjunct to other biomaterials. Clinical trials and case series with more than five cases were included. Seven in vitro studies evaluated the effect of EMD, placed on titanium surfaces: An increase in proliferation and viability of osteoblasts was observed in all but two studies. An increase in TGF-ß1 and osteocalcin production, alkaline phosphatase activity, and angiogenesis was also reported. Nine animal studies investigated the use of EMD at implant placement or for bone regeneration of peri-implant bone defects, and some of them reported a significant increase in bone formation or bone-to-implant contact. In four of eleven clinical trials on humans, EMD was successfully used at implant placement. The other seven evaluated the use of EMD in protocols for the treatment of peri-implantitis. In conclusion, the results of EMD seem promising, but further randomized clinical trials are needed to evaluate its efficacy.

Systematic review and meta-analysis on the adjunctive use of host immune modulators in non-surgical periodontal treatment in healthy and systemically compromised patients.

Considering the central role of inflammation in the pathogenesis of periodontitis, the combination of NSPT with different agents that can modulate the host immune-inflammatory response has been proposed to enhance the outcomes of NSPT. The aim of this paper is to systematically review the literature on the efficacy of systemic host modulators (HMs) as adjuncts to non-surgical periodontal therapy (NSPT) in improving pocket depth (PD) reduction and clinical attachment level (CAL) gain in healthy and systemically compromised patients. RCTs with ≥ 3 months follow-up were independently searched by two reviewers. Meta-analysis was performed when ≥ 3 studies on the same HM were identified. The quality of the evidence was rated according to the GRADE approach to rate the certainty of evidence. 38 articles were included in the qualitative assessment and 27 of them were included in the meta-analysis. There is low/very low evidence that the adjunctive use of sub-antimicrobial dose of doxycicline, melatonin and the combination of omega-3 and low dose aspirin (in type 2 diabetic patients) to NSPT would improve PD and/or CAL. Conflicting evidence is available on the efficacy of probiotics. Future studies controlling for confounding factors, using composite outcomes to define the endpoint of therapy and considering not only the patient- but also as the site-specific effect of systemic HMs are warranted. The dosage, posology and long-term effect of HMs still need to be clarified, also in association to the presence of systemic conditions potentially affecting the response to HMs administration.

The Impact of Peri-Implantitis on Systemic Diseases and Conditions: A Review of the Literature.

While periodontitis has been proven to have an impact on systemic conditions, such as cardiovascular diseases, pregnancy complications, or poor glycemic control in diabetic patients, the influence of peri-implantitis on systemic health has not been adequately explored in the literature as yet. The existing evidence suggests that peri-implant lesions lead to more intense inflammatory response than periodontitis. Given the analogies between periodontal diseases and peri-implantitis, the aim of the present paper was to review the scientific evidence about the potential correlation between peri-implantitis and systemic diseases and conditions. Two clinical trials on animals reported that experimental peri-implantitis determined an alteration in hematological and biological parameters. One human study explored the risk indicators for cardiovascular diseases and found that patients with peri-implantitis had significantly higher levels of triglyceride, uric acid, and white blood cells and lower levels of vitamin D. It was described in the literature that periodontitis affects cardiovascular health through a number of mechanisms, including the increase in systemic mediators of inflammation, which also has a role in the worsening of glycemic control in diabetic patients. Similarly, peri-implantitis may influence the systemic status through inflammatory cytokines such as IL-1, IL-6, and IL-10 and matrix metalloproteinases. One microbiological mechanism, based on the systemic dissemination of periodontal bacteria, has been hypothesized for cardiovascular diseases and pregnancy complications. Again, it is plausible that the same could occur in peri-implantitis. In conclusion, only few studies explored the systemic impact of peri-implantitis. Although changes in hematological parameters, biochemical parameters, and inflammatory markers have been reported in peri-implantitis, further studies are needed to investigate this correlation.

Medium- and Long-Term Survival Rates of Implant-Supported Single and Partial Restorations at a Maximum Follow-up of 12 Years: A Retrospective Study.

PURPOSE: To present medium- and long-term biologic outcomes of implant-supported single-tooth restorations and fixed partial dentures and to analyze their correlations with prosthesis and patient characteristics. MATERIALS AND METHODS: The records of patients treated with implant-supported fixed restorations between 2004 and 2019 reporting the presence or absence of peri-implantitis and/or implant failure were analyzed. The cumulative survival rate (%) over time was calculated, as well as the cumulative prevalence of units free of peri-implantitis. RESULTS: A total of 344 implants in 112 patients were included, with a mean follow-up period of 5.3 ± 4.0 years after loading. The cumulative survival rates for implants supporting single crowns and fixed partial dentures were 98.11% and 100% after 5 years, respectively, and 97.43% and 98.96% after 10 years, with an overall survival rate of 91.69% after 12 years. At the patient level, the implant survival rates were 95.42%, 92.73%, and 85.31% at 5, 10, and 12 years, respectively. The cumulative rate of implants free from peri-implantitis was 87.46% at the implant level and 72.39% at the patient level. Implant and prosthesis characteristics did not affect the long-term occurrence of implant failure or peri-implantitis. The development of peri-implantitis was statistically correlated with patient smoking habits, but not with history of periodontitis or with diabetes mellitus. CONCLUSION: Implants supporting single crowns and fixed partial dentures showed relatively high medium- and long-term survival rates that were not influenced by the implant or prosthesis characteristics, including the retention method. As for patient characteristics, only smoking was correlated with the occurrence of peri-implantitis.

Influence of teeth anatomical characteristics on the efficacy of manual toothbrushing manoeuvres.

PURPOSE: The aim of the study was to investigate the efficacy of two toothbrushing techniques on the amount of plaque accumulation and to evaluate how the changes were correlated to the anatomical characteristics of the anterior maxillary arch. METHODS: Thirty subjects of both genders were included, they were asked not to brush for 12 h. Afterwards, they were asked to manually brush the left side of their maxillary arch with the modified Bass technique and the right side adopting the roll technique. The comparison of photographs taken before and after the manoeuvres, using a plaque disclosing agent, allowed the researchers to measure the changes in plaque accumulation measured using the Quigley and Hein plaque scoring classification. Linear regression analysis was used to evaluate the correlation between such changes and the teeth and arch anatomical characteristics. RESULTS: A mean reduction of 9.6 ±â€¯5.2% considering both arches after brushing was observed. The changes in plaque accumulation were not different between the two techniques. The length of the line obtained joining the contact point between the central incisors and the contact point between the second premolar and the first molar on the left side and the distance between that line and the lateral incisor on the same side positively correlated to the decrease in the plaque scores (P = 0.046 and P = 0.044, respectively). CONCLUSION: Both tested techniques were effective in plaque removal in the anterior maxillary arches. However, the research for the anatomical factors influencing the amount of efficacy of the toothbrushing manoeuvres was inconclusive. We can hypothesise that the adoption of one adequate technique could be more important than the teeth characteristics.

Influence of Diabetes on Implant Failure and Peri-Implant Diseases: A Retrospective Study.

Diabetes is an important modifying factor of periodontitis, but its association with peri-implant diseases has not been fully explored and the existing literature reports controversial results. The aim of this retrospective study was to evaluate the influence of diabetes on peri-implantitis and implant failure. Smoking status, history of periodontal disease, presence of diabetes, diabetes type, therapy and glycaemia levels were collected in a total of 204 subjects treated with 929 implants, with a mean follow-up time of 5.7 ± 3.82 years after loading. Odds ratio (OR) for diabetes as a direct cause of peri-implantitis and implant failure were calculated, adjusted for smoking status and history of periodontitis. Nineteen patients were diabetic and most of them presented a good control of the disease at the time of surgery. The overall patient-level prevalence of peri-implantitis was 11.3%. Among diabetic patients, one developed peri-implantitis, whereas one experienced multiple implant failures. The calculated ORs, adjusted for smoking status and periodontitis, were not statistically significant. The results revealed no association between diabetes and peri-implantitis or implant failure coherently with the existing scientific literature. The actual influence of hyperglycemia on implant failure is still uncertain and new studies with larger cohorts of patients are needed.

Anatomical factors associated with gender recognizability: A study on intraoral standardized photographs.

AIM: The aim of this research was to evaluate the possibility of identifying the sex of 1 subject through visual assessment of a frontal photograph of dentition, and to investigate if some morphological characteristics are related to sex determination. METHODS: 5 expert dentists, 5 non-expert dentists and 5 laypeople were made to watch 100 intraoral photographs for 5 seconds each and to establish their sex. The responses of the participants and the baseline characteristics of photographed dentitions were analyzed. RESULTS: The proportion of right answers was 56.0% ± 8.2% in the group of expert dentists, 65.0% ± 6.0% in the group of non-expert dentists and 58.6% ± 4.5% in the group of non-expert people. The round shape of maxillary central incisors was related to the female gender (P = .006). The male condition was correlated with poor oral hygiene for 4 observers. Female sex perception was correlated with round morphology of upper central incisors for 3 observers. CONCLUSION: No difference in the ability to determine the sex was registered among groups, suggesting that sex perception is not strongly influenced by the characteristics of dentition.

Periodontal Regenerative Treatment of Intrabony Defects Associated with Palatal Grooves: A Report of Two Cases.

A palatal radicular groove (PRG) is a morphological deformity, occurring during tooth development. It is usually located on the palatal aspect of maxillary incisors and frequently associated with periodontal or endodontic-periodontal lesions. Some treatment options were described for such lesions, including primary endodontic treatment and periodontal surgery and extraction with intentional replantation after removal of a PRG and endodontic treatment. The present paper reported two cases of PRG-associated deep intrabony defects, successfully treated with periodontal surgery with enamel matrix derivative (EMD) application and mechanical removal of PRGs, avoiding endodontic treatment or retreatment. The complexity of the diagnostic process was also discussed.