Systematic review of surgical regenerative treatment for apicomarginal lesions in periapical surgery.

BACKGROUND: Apicomarginal lesions affect the root apex and root surface concurrently and reduce the success rate in periapical surgery. The purpose of this systematic review was to analyze the published literature on the surgical treatment of apicomarginal lesions in periapical surgery. MATERIAL AND METHODS: A systematic review was conducted on PRISMA statement. Three data bases (PubMed-Medline, Scopus, and Embase) were searched up to March 2023. The inclusion criteria for this systematic review encompass studies pertaining to apicomarginal lesions and their surgical treatment, both preclinical and clinical in nature (including randomized trials, prospective, and retrospective observational trials), without any language or time limitations. Exclusion criteria encompass studies with duplicated population data, no description of the surgical treatment or regenerative material. Different tools for the assessment of bias were applied for each study design Results: A total of 155 articles were searched and 10 were included. Studies on teeth with apicomarginal lesions undergoing periapical surgery showed a high success rate when regenerative techniques were used, resulting in reduced probing depth, increased bone formation on the root surface, increased root cementum formation, and reduced healing by junctional epithelium. Guided tissue regeneration, platelet-rich plasma or fibrin, and enamel matrix derivatives have emerged as alternative treatments offering favorable outcomes. CONCLUSIONS: The use of regenerative materials in periapical surgery could improve the prognosis of apicomarginal lesions. Future research in this field should aim to standardize classification and healing criteria to enhance comparability across studies and provide more conclusive evidence for optimal treatment approaches.

Diagnosis and indications for the extraction of third molars - The SECIB clinical practice guideline.

BACKGROUND: The removal of third molars (3Ms) is the most frequent surgical procedure in the field of Oral Surgery. As a result, the Spanish Society of Oral Surgery (SECIB) aims to create a Clinical Practice Guideline (CPG) that offers evidence-based recommendations for optimal clinical practice. Specifically, the CPG will focus on providing guidance regarding the indications and criteria for clinical and radiological diagnosis of patients with 3Ms. MATERIAL AND METHODS: This CPG was developed by the SECIB, following the methodological guidelines described in the methodological manual for the "Development of Clinical Practice Guidelines in the National Health System". Several PICO questions related to the diagnosis and indications for the extraction of 3Ms were formulated. The leading experts carried out the evaluation of the evidence and the formulation of specific recommendations. RESULTS: A total of 17 PICO questions were evaluated, addressing the indications, prognosis, diagnosis, and cost-benefit relationship of 3M extraction. CONCLUSIONS: The present Clinical Practice Guideline provides evidence-based recommendations on the diagnosis and indications for 3M extraction. These evidence-based recommendations can assist healthcare professionals and the general population in making informed decisions regarding the management of 3Ms.

Clinical practice guideline of the spanish society of oral surgery for oral surgery in patients with coagulation disorders.

BACKGROUND: The number of patients treated with coagulation disorders, and more specifically with anticoagulant therapy, has increased worldwide in recent years due to increased life expectancy in developed countries. The protocols for managing this type of patient in oral surgery has varied over recent years, especially after the appearance of new direct-acting oral anticoagulants (DOACs). The assessment of risk of bleeding in this type of patient when undergoing a surgical procedure continues to be a controversial issue for patients, dentists and general practitioners. The objective of this document is to offer recommendations, based on evidence, for decision making for patients with coagulopathies who require dental surgical intervention. MATERIAL AND METHODS: Based on the indications of the "Preparation of Clinical Practice guidelines in the National Health System. Methodological manual", we gathered a group of experts who agreed on 15 PICO questions based on managing patients with coagulation disorders in dental surgical procedures, such as fitting of implants or dental extractions. RESULTS: The 15 PICO questions were answered based on the available evidence, being limited in most cases due to the lack of a control group. Two of the PICO questions were answered by the experts with a grade C recommendation, while the rest were answered with grade D. CONCLUSIONS: The results of this review highlight the need to undertake well designed clinical trials with control groups and with a representative sample size.

Coronectomy of impacted mandibular third molars: a clinical and radiological retrospective case series study with 2-9 years of follow-up.

BACKGROUND: Impacted mandibular third molars occasionally are in intimate relation to the inferior alveolar nerve (IAN). Coronectomy has been proposed as a good alternative to prevent injury of the IAN. The present study evaluates the clinical and radiological outcomes of impacted mandibular third molars presenting radiographic signs associated with a high risk of IAN injury, and which were treated with the coronectomy technique. MATERIAL AND METHODS: A retrospective case series evaluated the outcomes of coronectomies of impacted mandibular third molars. The inclusion criteria were: available preoperative, immediate postoperative and two-year panoramic radiographs, preoperative cone-beam computed tomography (CBCT), and a complete case history. The clinical evaluation comprised intraoperative complications (mobilized fragments of root and damage to adjacent structures), short-term complications (sensory alterations and postoperative infection), and long-term complications (infection or oral exposure). The IAN position with respect to the roots, root shape, eruption status, third molar position, radicular-complex migration and bone above roots were radiographically evaluated as well. RESULTS: Approximately a total of 2000 mandibular third molars were removed from 2011 to 2022. Of these, 39 molars in 34 patients were partially extracted using the coronectomy technique. The mean age was 36 years (range 22-77), and the mean follow-up was 28 months (range 24-84). There were two short-term postoperative infections. One of them was resolved through reintervention to remove the roots after antibiotic treatment, while the other required hospital admission and removal of the roots. One case of short-term transient lingual paresthesia was also recorded. Two long-term oral exposures were detected, and the root fragments had to be extracted. There were no permanent sensory alterations. CONCLUSIONS: In our case series of 39 impacted mandibular molars in intimate contact with the IAN and treated with the coronectomy technique, the number of complications was low (two infections and a single case of transient lingual paresthesia), and no permanent sensory alterations were observed. Prospective studies, especially randomized clinical trials, are needed to compare this technique with conventional extraction.

Fresado a bajas revoluciones sin irrigación versus fresado a altas revoluciones con irrigación para la preparación del lecho implantológico: una revisión bibliográfica de estudios clínicos / Low-speed drilling without irrigation versus high-speed drilling with irrigation for implant bed preparation: a literature review of clinical studies

El fresado a bajas revoluciones sin irrigación ha sido descrito como una técnica para la preparación del lecho implantológico. Diversas ventajas sobre el fresado convencional han sido reportadas, sin embargo, existe la sospecha de que el sobrecalentamiento óseo pueda afectar los parámetros clínicos relacionados con el implante dental. El objetivo de esta revisión fue evaluar las diferencias clínicas entre el fresado de baja velocidad sin irrigación y el fresado de alta velocidad con irrigación para la preparación del lecho implantológico. Un total de 124 artículos fueron encontrados y finalmente 9 artículos se incluyeron en la revisión. La evidencia científica actual muestra tasas de éxito y pérdida ósea marginal periimplantaria sin diferencias estadísticamente significativas entre las dos técnicas. Además, la mayor cantidad y las mejores características histomorfológicas y celulares del hueso recolectado mediante el fresado a bajas revoluciones sin irrigación suponen una ventaja a tener en cuenta. El calentamiento óseo se mantiene por debajo de la temperatura crítica para la osteonecrosis térmica en ambas técnicas. En conclusión, el fresado a bajas revoluciones sin irrigación puede considerarse una técnica segura y predecible tanto como el fresado convencional. Además, la obtención de hueso autólogo en mayor cantidad y con mejores características celulares pueden aportar al clínico un recurso eficaz para ciertas situaciones clínicas. Aunque se necesitan mayor número de estudios clínicos. (AU)

Low-speed drilling without irrigation has been described as a technique for preparing the implant bed. Different advantages over conventional drilling have been mentioned, however, the suspicion of bone overheating and therefore its possible affectation to the clinical parameters related to the dental implant. The aim of this review was to assess the clinical differences between low-speed drilling without irrigation and high-speed drilling with irrigation for implant site preparation. A total of 124 articles were found and finally 9 articles were included in the review. Current scientific evidence shows success rates and marginal peri-implant bone loss without statistically significant differences between the two techniques. In addition, the greater quantity and the better histomorphological and cellular characteristics of the bone collected by drilling at low revolutions without irrigation represent an advantage to be taken into account. Bone temperature is maintained below the critical temperature for thermal osteonecrosis for the both techniques. In conclusion, low-speed reaming without irrigation may require as much a safe and predictable technique as conventional reaming. In addition, obtaining autologous bone in greater quantities and with better cellular characteristics can provide the clinician with an effective resource for certain clinical situations. However, more clinical studies are needed. (AU)

Influence of root width and dentin wall thickness evaluated by endoscopy upon the outcome of periapical surgery. A cohort study.

BACKGROUND: An analysis was made of the correlation between root width, the thickness of the remaining dentinal wall as determined by endoscopy, and the outcome of periapical surgery. MATERIAL AND METHODS: A retrospective cohort study was carried out involving patients subjected to periapical surgery between 2017 and 2019 at the University of Valencia (Valencia, Spain). One year after surgery, cone-beam computed tomography (CBCT) was used to evaluate healing against the preoperative volumes. The maximum root width was measured on the postoperative CBCT scan at the apical section of the treated root. This measurement was transferred to the intraoperative endoscopic image, where the minimum root width, peripheral dentin thickness, and minimum dentin thickness were recorded. Root measurements, and the position (maxillary or mandibular) and type of tooth (roots of incisors, canines, premolars or molars) were further correlated to periapical surgery outcome. RESULTS: A total of 51 patients, comprising 52 teeth and 62 roots, were included in the study. The mean measurements were: maximum root width (4.13±0.84 mm), minimum root width (2.46±0.72 mm), peripheral dentin thickness (0.77±0.2 mm) and minimum dentin thickness (0.4±0.2 mm). The success rate was 82.2%. Premolar roots showed a greater minimum dentin thickness (0.58±0.25 mm) (p<0.003) than incisor roots. No significant association was found between the different measurements and the healing rate at one year, though the roots that failed to heal showed smaller minimum dentin thickness values than the roots that healed correctly. The position and type of tooth did not influence healing outcome. CONCLUSIONS: The root width and thickness of the remaining dentin wall did not significantly influence healing. However, the roots that failed to heal showed smaller minimum dentin thickness values than the roots that healed correctly.

Endoscopic findings in periapical surgery. A cross-sectional study of 206 roots.

BACKGROUND: A study is made of the findings of high-magnification rigid endoscopy at the root end surface following apicoectomy of teeth subjected to periapical surgery. MATERIAL AND METHODS: A cross-sectional study was made of patients subjected to periapical surgery at the Unit of Oral Surgery and Implantology (University of Valencia, Valencia, Spain) between 2011 and 2019. Following apicoectomy, the root end surfaces were inspected, with the evaluation of untreated canals, isthmuses, craze lines, crack lines, opaque dentin and gaps. Likewise, an analysis was made of the association between patient age and the tooth type and restoration and the presence of craze lines, cracks, opaque dentin and gaps. RESULTS: The final sample consisted of 168 patients subjected to periapical surgery, with 177 operated teeth and 206 roots. Untreated canals were observed in 14 roots (6.8%). Isthmuses were identified in 74 roots (35.9%), particularly in the mesial root of the lower first molar (94.1%). In turn, craze lines were identified in 8.3% of the roots, cracks in 3.9%, and gaps in 53.4%. The prevalence of opaque dentin was 78.3%, with a greater presence in posterior teeth (90.3% in premolars and 86.2% in molars) than in anterior teeth (50.6%) (p<0.001). Patient age and tooth restoration showed no correlation to the studied parameters. CONCLUSIONS: Craze lines and crack lines were observed in less than 10% of the roots, though opaque dentin was identified in 73% of the roots, particularly in posterior teeth, and gaps were found in over half of the canals.

Intraoral onlay block bone grafts versus cortical tenting technique on alveolar ridge augmentations: a systematic review.

BACKGROUND: To review systematically the bone gain and superficial resorption rate of the onlay block bone grafts versus the cortical tenting technique, as well as secondarily study the postoperative complications, implant survival and success rates, and peri-implant marginal bone loss. MATERIAL AND METHODS: Following the recommended methods for systematic reviews and meta-analyses (PRISMA), an electronic search was performed in the PubMed (MEDLINE), EMBASE and the Cochrane Library of the Cochrane Collaboration (CENTRAL) databases to identify all relevant articles published up to March 2021 on onlay block bone grafts and cortical tenting technique. RESULTS: Eighteen papers complied with the inclusion criteria. In onlay grafts, the vertical bone gain mean was 4.24 mm, and resorption 20.91%; and 4.29 mm in the horizontal augmentation with a resorption of 10.28%. The complication rate was 14.8%. The implant survival and success rates were 100% and 92%; and the mean peri-implant bone loss ranged from 0.6 to 1.26 mm. In cortical tenting technique, the vertical bone gain mean was 6.17 mm and the resorption of 9.99%; and 5.55 mm in the horizontal augmentation with a 6.12% of resorption. The complication rate was 24.6%. The implant survival and success rates were 96.63% and 100%; and the mean peri-implant bone loss ranged from 0.27 to 0.77mm. CONCLUSIONS: Despite the limitations, both techniques offer a predictable way to reconstruct atrophic alveolar ridges, though the cortical tenting technique seems to achieve a greater bone gain and a lower surface resorption. Current evidence is still limited due to the inadequate follow-up, lack of information referred to methodological quality and sample attrition.

Esplendor y ocaso de la cirugía experimental. Recuerdo histórico / Splendor and sunset of experimental surgery. Historical memory

La cirugía experimental ha sido en las últimas décadas la base del desarrollo del conocimiento y de la técnica quirúrgica. Hanexistido numerosos centros que ha dispuesto de este tipo de infraestructuras casi siempre ligados a los hospitales. Por otro lado, lacirugía ha evolucionado a procedimientos mínimamente invasivos con un claro cambio del perfil de la técnica quirúrgica, abandonándose en parte los procedimientos tradicionales. Además, se han desarrollado de forma relevante las nuevas tecnologías yen especial la informática que han aportado nuevas prestaciones. Todo ello ha hecho que se haya reconsiderado estratégicas yplanificaciones del pasado que ha quedado superadas por nuevos enfoques. Se analiza en el trabajo las aportaciones de la cirugíaexperimental, se valora su utilidad actual y se discute su utilidad futura. (AU)

Experimental surgery has been in recent decades the basis for the development of knowledge and surgical technique. There havebeen numerous centers that have had this type of infrastructure almost always linked to hospitals. On the other hand, surgery hasevolved to minimally invasive procedures with a clear change in the profile of the surgical technique, partially abandoning traditional procedures. On the other hand, new technologies have been developed in a relevant way, especially computing, which has provided new features. All this has led to a reconsideration of past strategies and plans that have been superseded by new approaches.The contributions of experimental surgery are analyzed in the work, its current usefulness is assessed and its future usefulness isanalyzed. (AU)

Is periapical surgery follow-up with only two-dimensional radiographs reliable? A retrospective cohort type sensitivity study.

BACKGROUND: Two-dimensional (2D) radiographic techniques are commonly used for assessing lesion prognosis after endodontic surgery. The present retrospective cohort study analyzes the sensitivity and ability of different radiographic techniques in obtaining area and volume measurements of periapical lesions. MATERIAL AND METHODS: Preoperative and follow-up (6-48 months) periapical and panoramic radiographs (index test) and cone-beam computed tomography (CBCT) images (reference standard) were selected from an endodontic microsurgery database. Sensitivity was analyzed independently by two examiners. The areas of the 2D radiographic images and CBCT volumes were studied using Itk-Snap software and Romexis viewer. RESULTS: The sample comprised 105 patients and 105 teeth, with a mean follow-up of 21 months (range 6-48). Preoperatively, CBCT detected all the periapical areas, periapical radiography detected 67, and panoramic radiography detected 60. Postoperatively, of the 52 cases in which CBCT detected remains of the periapical area, periapical radiography detected 22, and panoramic radiography detected 17. The measurements of the areas obtained by the 2D methods, and the volumes obtained by CBCT, had to be transformed into linear measures for comparison purposes. The measurements were found to be significantly different in both the preoperative and the follow-up images. CONCLUSIONS:  Periapical radiography showed greater sensitivity than panoramic radiography, both preoperatively and at follow-up. The lesions measured with CBCT were larger, with significant differences than as evidenced by the periapical and panoramic radiographs.

Social cognition and its relationship with sociodemographic, clinical, and psychosocial variables in first-episode psychosis.

People with first episode of psychosis (FEP) show deficits in social cognition, which have been linked to several sociodemographic, clinical, and psychosocial variables. The aim of the present research was to study social cognition as a whole measure in people with FEP comparing it with a healthy control sample, to study gender differences, and to examine the relationship between sociodemographic, clinical, and psychosocial variables and social cognition in the onset of psychosis. A descriptive, cross-sectional study was performed. The study sample consisted of 63 people (18 females; 45 males) with a diagnosis of FEP and a healthy control group (78 participants: 38 females; 40 males). All the participants were assessed with the social cognitive domain of the MATRICS Consensus Cognitive Battery (MCCB) and several questionnaires related to studied variables. Our results indicated that compared with healthy controls, people with FEP showed social cognition deficits. Furthermore, premorbid IQ was the most relevant variable in social cognition performance in FEP sample. The findings of the present research may be taken into account in clinical practice to improve the intervention with people with FEP.

Regeneración ósea guiada simultánea en implantes cigomáticos con una aproximación exteriorizada en una atrofia maxilar avanzada / Guided bone regeneration and zygomatic implants: a case report

Se presenta un caso clínico en el que se rehabilita a una paciente con maxilar superior atrófico mediante una combinación de implantes cigomáticos, colocados mediante una aproximación exteriorizada, e implantes anteriores convencionales palatinizados. Se realizó un procedimiento de regeneración ósea guiada alrededor de los implantes cigomáticos para obtener un mayor grosor de la cortical vestibular y palatina alrededor de los implantes del maxilar superior y mejorar el pronóstico. A un año de la carga protésica, el hueso periimplantario se mantiene estable

A clinical case is presented in which a patient with atrophic upper jaw is rehabilitated by a combination of zygomatic implants, placed using an exteriorized approach, and conventional palatalized anterior implants. A guided bone regeneration procedure is performed around the zygomatic implants to obtain a greater thickness of the facial bone and improve the prognosis. One year after loading, the peri-implant bone remains stable

Hemostatic agents in endodontic surgery of maxillary molars: A randomized controlled pilot study of polytetrafluoroethylene (PTFE) strips as an adjunct to epinephrine impregnated gauze versus aluminum chloride.

BACKGROUND: Hemostasis is of critical importance in endodontic surgery. Studies on bleeding control in maxillary molars are scarce. The present study compares the efficacy of two hemostatic techniques in controlling bleeding in endodontic surgery. MATERIAL AND METHODS: A randomized two-arm pilot study involving 30 patients with peri-radicular lesions in maxillary molars (first and second molars) was carried out including the following hemostatic agents: polytetrafluoroethylene (PTFE) strips as an adjunct to epinephrine impregnated gauze (test group; n = 15) and aluminum chloride (Expasyl™) (control; n = 15). Bleeding control was independently assessed by the surgeon and by two blinded observers before and after application of the hemostatic agent, and was classified as either adequate (complete bleeding control) or inadequate (incomplete bleeding control). RESULTS: Bleeding control was similar in both groups. Simple binary logistic regression analysis failed to identify variables affecting bleeding control. Only the height of the keratinized mucosal band (≥ 2 mm) suggested a decreased risk of inadequate bleeding control of up to 89% (OR=0.11; p=0.06). CONCLUSIONS: No difference in the efficacy of bleeding control was observed between PTFE strips as an adjunct to epinephrine impregnated gauze and aluminum chloride in maxillary molars.

Quality and readability of the dental information obtained by patients on Internet: criteria for selecting medical consultation websites.

BACKGROUND: The main objective of this study is to examine the quality of the information available for patients online with regards to the apicoectomy surgical procedure, both on general and critically selected websites. The hypothesis is that general websites has less quality than other that have been pre-selected. MATERIAL AND METHODS: A search for the English term "apicoectomy" was performed online. The first 100 websites that appeared in both Google and Yahoo were analysed. Seven validated instruments were used for these two dimensions: quality (DISCERN, JAMA and EQIP), and readability (FRES, Fog Scale, FKRGL and SMOG). RESULTS: A total of 21 websites (10.5%) were selected. The readability of the websites in both groups was difficult or very difficult. With regards to the quality of the websites, the DISCERN instrument indicated an average value of 2.28 [2.14-2.39] for all of the websites, therefore indicating very low quality with serious defects; however, in the selected websites, the average quality was 3.16 [2.84-3.48], indicating potential, but not serious defects (p<0.001). There were statistically significant differences for the FRES values (p = 0.030), with a greater readability in the selected group of websites. CONCLUSIONS: We believe that it is very important for the population to become aware of and learn how to use certain exclusion criteria when selecting medical consultation websites, as in doing so, they will be able to obtain a higher quality of information from these websites.

Patient morbidity after impacted third molar extraction with different flap designs. A systematic review and meta-analysis.

BACKGROUND: To review the literature on the effect of different surgical flaps upon patient morbidity (pain perception, trismus, swelling and osteitis) after impacted third molar extraction. MATERIAL AND METHODS: An electronic and complementary search of main databases and grey literature was performed up to January 2019 to retrieve randomized clinical trials. The Cochrane risk of bias assessment tool was used for methodological appraisal. A random-effects meta-analysis was conducted of pain perception and trismus. RESULTS: From the initially 1314 screened studies, only 11 were included in the qualitative synthesis, and 5 in the meta-analysis. There were no statistically significant differences in pain between the envelope and triangular flap designs over time, except on the sixth postoperative day, when the envelope flap proved more painful. Regarding trismus, statistically significant differences were observed on the seventh postoperative day, with greater mouth opening in the envelope flap group than in the triangular flap group. There were no clear differences in swelling and osteitis among the flap designs. CONCLUSIONS: Despite its limitations, the present meta-analysis found no clear differences in patient morbidity between the different flap designs.

Oral rehabilitation with dental implants in patients with recessive dystrophic epidermolysis bullosa: A retrospective study with 2-15 years of follow-up.

BACKGROUND: Epidermolysis bullosa (EB) comprises a group of hereditary disorders characterized by mechanical fragility of the skin and mucous membranes, with the development of blisters and vesicles in response to minimum tissue friction. Recessive dystrophic epidermolysis bullosa (RDEB) with generalized involvement is the most common subtype in the oral cavity. The present study was carried out to investigate dental implant survival, peri-implant tissue condition, patient satisfaction, and the impact of treatment upon the quality of life of patients with RDEB rehabilitated with implants and full-arch implant-supported prostheses. MATERIAL AND METHODS: Thirteen patients with RDEB underwent dental implant treatment between September 2005 and December 2016. A retrospective study was made to analyze implant survival, peri-implant tissue health and patient satisfaction. RESULTS: A total of 80 implants were placed (42 in the maxilla and 38 in the mandible) in 13 patients between 20-52 years of age and diagnosed with RDEB. All the implants were rehabilitated on a deferred basis with 20 full-arch prostheses. Fifteen fixed prostheses and 5 implant-supported overdentures were placed. The implant survival rate was 97.5% after a mean follow-up of 7.5 years after prosthetic loading. Fifty percent of the implants showed mucositis at the time of evaluation. Probing depth was maintained at 1-3 mm in 96.2% of the implants, and bleeding upon probing was observed in 67.5% of the implants. There was a high prevalence of bacterial plaque (85%). CONCLUSIONS: The treatment of edentulous patients with RDEB by means of implants and implant-supported prostheses is predictable as evidenced by the high success rate, and improves patient self-esteem and quality of life.

Volumetric variation of peri-implant soft tissues in convergent collar implants and crowns using the biologically oriented preparation technique (BOPT).

BACKGROUND: To evaluate the changes in the peri-implant soft tissues of convergent collar implants with biologically oriented preparation technique (BOPT) crowns, 10 months after loading. MATERIAL AND METHODS: A pilot study was carried out from January 2016 to October 2017 involving 14 patients with one or two implants in the posterior mandibular sector. A total of 32 convergent collar implants were placed using a non-submerged protocol. Three months later the provisional cemented crowns were fitted using the BOPT approach with the finish line 1-1.5 mm below the gingival margin, simulating coronal emergence of a natural tooth. The soft tissue changes were measured with an intraoral scanner at two different timepoints: a) on the day of provisionalization, before prosthetic loading; and b) 10 months later without the provisional prosthesis. The STL files were superimposed and the soft tissue changes were recorded using a color scale with measurement of the volumetric changes in mm3. RESULTS: A mean increase in peri-implant mucosal volume of 64.7 mm3 was observed in 29 implants. The zones with the greatest increase in soft tissue volume were the papillae of implants with adjacent teeth and the peri-implant buccal margin. Three implants showed a mean decrease in soft tissue volume of -25.1 mm3. CONCLUSIONS: The fitting and design of crowns using the biologically oriented preparation technique (BOPT) over convergent collar implants affords a significant increase in peri-implant soft tissue volume both at the level of the papillae and in the buccal margin.

Impact of crestal and subcrestal implant placement upon changes in marginal peri-implant bone level. A systematic review.

BACKGROUND: To systematically assess studies analyzing peri-implant bone loss in implants placed in crestal and subcrestal position. MATERIAL AND METHODS: Following the recommended methods for systematic reviews and meta-analyses (PRISMA), an electronic search was conducted in the PubMed (MEDLINE), EMBASE and LILACS databases to identify all relevant articles published up until April 2017. The search included human studies comparing marginal bone loss (MBL) between a control group and a study group with a minimum of 10 patients and a minimum follow-up of 6 months after prosthetic loading with rough neck implants. Two independent reviewers assessed the risk of bias in the selected studies based on the Newcastle-Ottawa scale for observational studies and the Cochrane Collaboration for clinical trials. RESULTS: Of 342 potentially eligible items, 7 complied with the inclusion criteria. One article was retrieved through the manual search. Eight articles were finally included: five experimental and three observational studies. The risk of bias assessed by the Cochrane Collaboration and Newcastle-Ottawa showed a high risk of bias. The mean follow-up period was 21 months (range 6-36 months). In four studies, implants placed in a crestal position presented higher MBL than subcrestal implants - the differences being significant in one study, while in three studies, implants placed in a subcrestal position presented greater MBL than crestal implants, with significant differences in only one study. CONCLUSION: Despite its limitations, the present systematic review did not find better outcomes between crestal and subcrestal implant placement, however, new studies will be needed, involving improved designs and the standardization of protocols to allow statistical comparisons and the drawing of firm conclusions.

Effect on osseointegration of two implant macro-designs:A histomorphometric analysis of bicortically installed implants in different topographic sites of rabbit's tibiae.

BACKGROUND: To evaluate the effect of two different implant macro-designs on the sequential osseointegration at bicortically installed implants in the rabbit tibia. A further aim is to compare the osseointegration at different topographic zones. MATERIAL AND METHODS: 27 New Zealand rabbits were implemented. Two implants, one for each macro-design (Ticare Inhex® or Ticare Quattro®, Mozo-Grau, Valladolid, Spain), were randomly implanted in the diaphysis or metaphysis of each tibia. The flaps were sutured to allow a submerged healing. The animals were sacrificed after 2, 4 or 8 weeks. Ground sections were prepared and analyzed. RESULTS: No statistically significant differences were found between the two groups for newly formed bone in contact with the implant surface, being about 16%, 19% and 33% in both groups, after 2, 4, and 8 weeks of healing. Bone apposition was slightly higher in the diaphysis, reaching values of 36.4% in the diaphysis, and 29.3% in the metaphysis at 8 weeks of healing. It was observed that the implant position showed a statistical significance regarding BIC values at 4 and 8 weeks (p<0.05). Multivariate analysis fails to detect statistical significant differences for the interaction between implant designs and topographic site. Ticare Quattro® design had a slight better BIC values at diaphysis sites across healing stages, but without reaching a statistical significance. CONCLUSIONS: The both implant macro-designs provided similar degrees of osseointegration. Bone morphometry and density may affect bone apposition onto the implant surface. The apposition rates were slightly better in diaphysis compared to metaphysis.

Salivary myeloperoxidase and malondialdehyde are increased in patients exhibiting an asymptomatic mandibular impacted third molar.

BACKGROUND: To determine whether saliva is a good means of evaluating concentrations of oxidative stress biomarkers, analyzing the correlation between concentrations in saliva and in follicular tissue, and to compare biomarker concentrations in patients with one asymptomatic mandibular impacted third molar (MITM) (before extraction) with a healthy control, and to determine how biomarkers are modified by extraction. MATERIAL AND METHODS: 80 patients with one asymptomatic MITM and 80 healthy controls were included. Saliva samples were collected from all subjects (before extraction in the study group) to evaluate Myeloperoxidase (MPO) and Malondialdehyde (MDA) concentrations. Follicular tissues were obtained during surgery to measure biomarkers. One month after extraction, saliva samples were collected to assess changes of oxidative stress. RESULTS: Salivary MPO and MDA showed positive correlation with concentrations in follicular tissue (MPO: correlation coefficient=0.72, p=0.025; MDA: =0.92, p=0.001). Patients with asymptomatic MITMs showed higher salivary concentrations of oxidative stress biomarkers than healthy control subjects, with statistical significance for both MPO (p<0.001) and MDA (p<0.001). One month after extraction, salivary biomarkers decreased significantly in the study group (p<0.001). CONCLUSIONS: Salivary MPO and MDA are higher among patients with one asymptomatic MITM, but these levels decrease significantly one month after surgical extraction. The large decrease in oxidative stress biomarkers could justify third molar extraction despite the absence of symptoms.