Oral

Objectives: To review dento-facial evolution based on fossil data, comparative anatomy, developmental biology and genetics. Modern human evolution reveals profound insight into the technical and biological challenges faced by clinicians in daily practice of dentistry. Materials and Methods: An analysis and review of the literature is presented to further explain the evolutionary forces that have shaped hominins. Results: Modern human evolutionary morphological and biological adaptations allowed improvement of cognitive ability, facial expression, smile and language. However, the increased cranial capacity correlates inversely with a decrease in size of the maxillary and mandibular bones, weakening of the muscles and facial shortening, contributing to dento-facial complications. Moreover, the distinctive differences in origin and development of the dento-facial components have further contributed to these maladies. In addition, human lifestyle transition from nomadic to sedentary increased the incidence of oral diseases. Conclusions: Knowledge of human evolutionary patterns can improve the quality of response by clinicians to biological challenges. The limitations in current treatment modalities can be explained, in part, due to the complexity of the life forms that resulted from evolution. Although there are no rules to predict how evolutionary forces will shape modern humans, the evolution of the dento-facial complex reveals profound insight into our connection to other forms of life and nature. Full article

Ephrin-B1,-B2 and -B3 proteins share a high degree of sequence similarity. Investigation of these proteins as putative prognostic markers in human cancers including oral squamous cell carcinoma (OSCC) has been limited by challenges in generating specific antibodies against them. The current study examined the reactivity of a polyclonal anti-human ephrin-B2 antibody (HPA008999) against ephrin-B proteins and investigated the prognostic significance of immunoreactivity of the same antibody at different intra-tumor sites in OSCC specimens. By amino acid sequence comparison, immunocytochemistry and Western blot analysis on cell lysates and precipitates from HEK-293T cells transfected with EFNB1, EFNB2, or EFNB3 expression constructs, we demonstrated that HPA008999 reacted to all ephrin-B proteins. Using immunohistochemistry (IHC) with the HPA008999 antibody in a cohort (n = 131) of OSCC, we showed high immunoreactivity at the tumor center, but not at the tumor invading front, was significantly associated with worse 5-year overall survival probabilities. In conclusion, the HPA008999 antibody reacted to all ephrin-B proteins and the immunoreactivity at the tumor center might be useful as a prognostic marker in OSCC. These data underscore the need for the investigation of antibodies for cross-reactivity to similar protein members for obtaining reliable and meaningful results in IHC based biomarker studies. Full article

On the 8th and 9th of May 2021, an online conference was organized to connect Italian physicians, dentists and oral care specialists, students, nurses, psychologists, dental hygiene experts, and other professionals to discuss controversial issues about Medication-Related Osteonecrosis of Jaw (MRONJ). The first section evaluated differences between Italian recommendations, released on 2020 by Italian Societies of Oral Pathology and Medicine (SIPMO) and Maxillofacial Surgery (SICMF), and other international practice guidelines or documents. A first round table gathered expert opinions about MRONJ definitions and staging systems. Another round table was dedicated to opinion of drug prescribers (oncologists, hematologists, rheumatologists, and other physicians treating osteoporosis). Educational sessions illustrated the main differences between previous (2013) and more recent (2020) Italian recommendations. A large space was dedicated to the presentation of scientific contributions from centers in Italy, divided in specific sessions (epidemiology; case series; special case reports; prevention experiences; MRONJ treatment). Conclusions: in an innovative web conference, talks and scientific reports underlined importance of adequate imaging study of bone in definition and staging of MRONJ cases, the role of surgery in treatment of the disease, and the value of oral hygiene in the prevention. Full article

The frequency of epidermoid cysts in the maxillofacial region is relatively low. Reported: a case of a giant sublingual epidermoid cyst on the floor of the mouth. Case: 38-year-old woman. Chief complaint: oral swelling and respiratory distress. History of present illness: no special notes. Current medical history: she was aware of swelling of the floor of the mouth six months before visiting our department and was referred to our department because of increasing size. Present symptoms: at the time of examination, forced respiration and dysarthria were observed and a spherical soft elastic and well-defined mass was observed on the floor of the mouth. Due to the lesion, the tongue was displaced to the pharyngeal side and the tip of the tongue could not be confirmed. Imaging tests revealed a 65 mm × 76 mm × 54 mm well-defined mass on the mylohyoid muscle, and a dermoid or epidermoid cyst was suspected. Based on the clinical diagnosis of the cyst, the bulk of the cyst contents was reduced under general anesthesia, and the cyst was removed by intraoral surgery. The pathological diagnosis was an epidermoid cyst. For sublingual giant epidermoid cysts, removal by content reducing surgery was considered to be effective. Full article

Aims. The purpose of this systematic review was to evaluate studies that assessed denture–mucosa pressure distribution and pressure–pain threshold and their methodology, used to measure such pressure distributions, mainly in complete and implant overdentures. Materials and methods. An electronic search of the relevant full-text peer-reviewed literature on denture–mucosa pressure distribution was done. Searches were performed independently by two researchers by using the OVID Medline, PubMed and Web of Science databases from 1 January 1946 to 31 December 2021 using the following MeSH terms; (denture OR complete dentures OR implant supported dentures) AND (mucosa OR mucous membrane) AND (pressure OR hydrostatic pressure). Only those publications in the English language were included. Furthermore, a manual search of the citations of the included studies was done to ensure a thorough search was conducted. Results. A full text review resulted in a total of eighteen studies. Of these, seven evaluated various intraoral pressures, two investigated the pressure–pain threshold in edentulous oral mucosa, five measured intraoral pressure through finite element analysis/FEA studies, two demonstrated pressure transducer and pressure measuring systems, and two investigated the comparison between implant-overdentures and complete dentures. Conclusions. To date, there is no study that assesses the pressure distribution on oral mucosa to provide a standardised and validated baseline pressure range which can be used to improve the designs and materials used for fabricating complete dentures. The relationship between pressure on the oral mucosa and the pain threshold of denture-wearing patients still remains poorly understood. There is yet no baseline data which can be universally applied for future studies; to correlate the oral mucosa pressure and pain threshold of edentulous patients encourages further research, especially comparing mucosa pressure under different denture designs for both complete and implant overdentures. Full article

The purpose of this systematic review was to identify the different methods used to measure artificial teeth wear and to determine which denture teeth (or which combination of tooth types) have better wear resistance. The focused patient, intervention, comparison, and outcome (PICO) question for this review was “which available denture teeth or combination of teeth have higher wear resistance?” The method of testing and measuring the artificial teeth wear was also evaluated as a secondary outcome. We searched OVID Medline, PubMed and SCOPUS using the following terms (MeSH words) with any synonyms and closed terms: “wear”, “denture teeth”, “denture tooth”, or “artificial tooth”, “tooth wear”, or combination of “denture tooth wear”. Database searches were limited to the English language and studies published between years 1997 and 2021. Further hand searches were carried out of studies identified from the bibliographies of relevant articles. The electronic data base search identified 293 articles of which 213 were eliminated after removing duplicates and screening the titles of the articles. A further 31 articles were eliminated upon application of the exclusion criterion and full text reading because they were either not in the English language or were review articles. Only 41 articles met the inclusion criterion; along with addition of one hand search article, a total of 42 articles were included in the review. The studies showed that rate of denture teeth wear is influenced by factors such as the material and composition of the artificial teeth, the denture tooth antagonist, the tooth being replaced, patient’s age and sex, the type of removable prosthesis and the amount of the superficial layer removed during occlusal adjustments. The testing parameters were inconsistent across all studies. In conclusion, artificial teeth of same material should be used as antagonists where possible, and the superficial outer layer of the teeth must be preserved as much as possible during occlusal adjustments to enhance wear resistance. Denture teeth should be selected taking into consideration the tooth being replaced, the age and sex of the patient, and the type of prosthesis. Incorporation of nano fillers into acrylic resin teeth does not increase wear resistance; therefore, there is no evidence to favour the use of nano-filled composite teeth over micro-filled or conventional acrylic resin teeth. Full article

The aim of this study is to capture the dental anxiety of patients in a dental clinic. A special focus was placed on the measurement of the course of possible anxiety occurring during a single dental visit with different surgical procedures. Therefore, 129 patients were interviewed in an oral surgical clinic. The course of possible anxiety was measured with a short questionnaire about the current stress (“Kurzfragebogen zur aktuellen Beanspruchung”, KAB), which was completed by the patients at three different times in the waiting room, as well as before and after the treatment in the consulting room. In the waiting room, the patient answered a questionnaire, including the following instruments: questions about age and sex, KAB (stress), and the Dental Anxiety Scale (DAS, anxiety). According to the DAS, 64.1% belonged to the low-anxiety group, 29.7% belonged to the medium-anxiety group and 6.2% belonged to the high-anxiety group. For all groups, the stress just before the treatment was the highest and it was the lowest after treatment. The KAB values of the female patients were significantly higher than those of the male patients. About one third of the patients suffered from dental anxiety. Full article

Aim: To measure the bond strength between two different CAD/CAM PMMA denture base resins and three different types of gum characterisation composites. Materials and Methods: CAD/CAM single cross-linked (Telio CAD) and double cross-linked (Vivodent CAD) resins were prepared, obtaining a total of 180 bar specimens. Each specimen was prepared according to the manufacturer’s instructions. The specimens were bonded to three different characterisation composites with varying viscosities; Kulzer Pala-creactive (P), Ivoclar SR Nexco (S), Shofu Ceramage (F). All the specimens were then tested using a chevron-notched three-point bond strength test in a universal testing machine to obtain fracture energy release toughness (MPa√m) and bond strength (MPa). The specimens were thermocycled to simulate 6 and 12 months of ageing in vivo. The results were statistically analysed (SPSS). The fractured surfaces of the tested specimens were examined with a scanning electron microscope (SEM) to evaluate the failure modes. Results: Pala-creactive characterisation composites showed the highest overall bond strength (3.49 ± 0.86 MPa) and fracture toughness (1.59 ± 0.34 MPa√m) when bonded to both CAD PMMA denture resins, which were statistically higher than the values obtained when they were bonded to Telio (p < 0.001). The Ceramage composite showed the lowest bond strength (1.05 ± 0.59 MPa) and fracture toughness (0.47 ± 0.4 MPa√m). The dominant mode of failure for all groups was mixed. Conclusion: Single cross-linked PMMA (Telio) showed a higher overall bond strength compared to double cross-linked PMMA when bonded to three different characterisation composites. Telio CAD showed a clear bond strength decrease after 6 and 12 months of artificial ageing, while Vivodent CAD showed a bond strength increase. Full article

Objectives: To measure and compare the bond strength between three different types of ceramics and resin cement, as well as the degree of conversion of resin cement after using different light-curing units and curing modes. Methods: Three types of ceramics—Leucite-reinforced (Empress CAD), Lithium disilicate (Emax CAD), and Zirconia (Emax ZirCAD)—of varying thicknesses (1.5 mm and 2.0 mm) were bonded to a light-cure resin cement (Variolink Esthetic LC). Light-curing was carried out using a monowave LCU (3M Elipar DeepCure-S LED Curing Light with irradiance of 1470 mW/cm²) and with polywave LCU (Ivoclar Bluephase PowerCure) using High, Turbo, and 3 s curing modes, respectively (1200, 2100, 3000 mW/cm²). A chevron-notch bond strength test (total n = 288) was conducted to calculate the fracture energy and interfacial bond strength (J/m²). The degree of cure (%DC) of the residual resin cement on debonded surfaces was measured using Fourier Transform Infrared Spectroscopy (FTIR). Collected data were statistically analysed under SPSS ver. 27 by conducting an ANOVA and Bonferroni post hoc test. The mode of failure was established using a scanning electron microscope (SEM). Results: A significant difference in interfacial bond strength was found between the three types of ceramic material groups (p < 0.01). Cement cured through Empress that was 2 mm thick showed the highest bond strength (1.36 ± 0.46 J/m²), while the lowest was observed (0.26 ± 0.07 J/m²) in 2 mm Emax CAD using the 3 s mode. The use of different LCUs and curing modes had a significant influence on the %DC of resin cement seen in all groups, except 2 mm Emax ZirCAD. The dominant mode of failure for Empress, EmaxCAD, and EmaxZirCAD were cohesive, adhesive, and mixed, respectively. Conclusions: The type of ceramic and its thickness can significantly affect bond strength, and the results showed that polywave LCU is more effective than monowave LCU when curing through ceramics. Full article

Background: Carcinoma cuniculatum (CC) is a rare subtype of squamous cell carcinoma that is difficult to diagnose owing to the lack of cellar atypia and/or associated oral epithelial dysplasia. The prognosis is good given proper resection, but it often has a poor prognosis with recurrence. We present the case of a 78-year-old man who visited our department with an ulcer around the implant in tooth 35. With Nikolsky’s phenomenon in the gingiva, a detailed examination revealed pemphigus vulgaris. Steroid administration remarkably improved the oral symptoms but caused osteomyelitis and rapid bone destruction, leading to pathological fracture. After multiple biopsies, mandibular segment resection was performed with a diagnosis of mandibular osteomyelitis, and no malignant findings were found. Four months later, the wound reopened, a white keratinized lesion appeared, and a biopsy revealed CC. Unresectable tumor infiltration was already observed, but the patient died of aspiration pneumonia 15 months after diagnosis. Conclusions: It took 20 months to make a definitive diagnosis of CC in this case. Pemphigus vulgaris may have made the diagnosis particularly difficult. Since other CCs are often diagnosed with osteomyelitis or odontogenic keratocyst preoperatively, we recommend keeping in mind the possibility of CC in refractory cases. Full article

Denosumab has proved effective at low doses in increasing bone mineral density in osteoporosis patients. In contrast to high-doses antiresorptive therapy, denosumab has a transient effect on the inhibition of the bone remodeling process, suggesting that denosumab-related osteonecrosis is a self-limiting disease, with a high curative potential of surgery when performed after a proper duration of receptor activator of nuclear factor-kB ligand (RANKL) inhibitor suspension. We report the long-term clinical and radiological (Computed Tomography—CT scan) data of a patient affected by secondary osteoporosis (cancer treatment-induced bone loss—CTIBL for metastatic breast cancer) who underwent surgical treatment for stage II denosumab-related osteonecrosis of the upper maxilla 7 months after denosumab suspension. A minimally invasive approach was performed with the extraction of the first right upper molar and debridement of the surrounding alveolar bone. After surgery, the patient was followed up at three-month intervals up to 1 year, and clinical and radiological data (CT scan) were recorded at each follow-up for the early detection of signs of recurrent disease. The mucosal healing remained stable in the long term, with radiological signs of bone remodeling in the post-operative site since the 6-month follow-up. The presented case strengthens the hypothesis that denosumab induces temporary alterations of bone turnover with a predictable curative effect of minimal surgical procedures in cases of denosumab-related osteonecrosis of the jaw. Full article

The aim of this in vitro study was to investigate three different cements for their suitability to provide semi-permanent cementation, and to compare the retention forces of implant-supported single crowns (SC) and three-unit fixed dental prostheses (FDP) luted with these cements. Twenty-four methacrylate models were supplied with three implants/abutments each to simulate the condition of SCs/FDPs. Cobalt-chromium frameworks were fabricated, sandblasted (Al₂O₃/50 µm/0.2 MPa) then cemented with glass-ionomer (KTC), polycarboxylate (DUR) or self-adhesive resin cement (RXU). Specimens were stored in a saline-solution (NaCl/37 °C/24 h) or subjected to thermocycling. A universal testing machine and a pull-off device were used to remove the copings. The multi-factor ANOVA showed that the retention force differed significantly among all cements for the SCs after NaCl storage (p < 0.05). Mean retention forces (in Newtons) after NaCl storage were (SCs/FDPs): KTC 170/352, DUR 409/406, RXU 265/426, and after thermocycling (SCs/FDPs): KTC 156/262, DUR 306/380, RXU 494/508. FDPs showed higher retention values in comparison to SCs. For SCs, artificial aging with thermocycling resulted in a significant retention increase for RXU, whereas the retention of KTC and DUR was decreased. Glass ionomer can be used as a semi-permanent cement for both SCs and FDPs. Polycarboxylate cement is considered semi-permanent after one year of aging. Full article

The surgical extraction of the lower third molar is widely practiced in oral surgery. Inflammatory complications such as pain, swelling, and trismus can cause discomfort to the patients after third molar extraction. Several methods have been used to reduce these postoperative sequelae, including the use of corticosteroids, nonsteroidal anti-inflammatory drugs, analgesics, antibiotics, less traumatic surgical methods, and the use of photobiomodulation. This narrative review summarizes the current evidence on the effect of photobiomodulation on pain, facial swelling and trismus after third molar surgery. A literature search using MEDLINE (NCBI PubMed and PMC), EMBASE, Scopus, Cochrane library, Web of Science, and Google Scholar was undertaken up to October 2021. Forty-one articles met the inclusion criteria. Photobiomodulation can be considered an alternative and useful method for controlling pain following impacted wisdom tooth surgery. The effectiveness of PBM in reducing swelling and trismus is still controversial. This review highlights the lack of consensus in the literature on protocols used in PBM therapy. Full article

Medication-Related Osteo-Necrosis of the Jaws (MRONJ) is a severe painful complication of the long-lasting administration of bisphosphonates and anti-resorptive and anti-angiogenetic drugs in neoplastic and dysmetabolic patients, secondary to minor surgical oral interventions or chronic epithelial decubitus ulcers. Its pathogenesis is still largely unknown even if the activity change of the osteoclasts plays a relevant role in bone remodeling. The management of these patients aims to prevent the onset of the pathology or to reduce the pain and remove the necrotic bone, promoting the healing of the pathological area. Photobiomodulation therapy (PBMT), the therapeutic application of low-energy laser or LED lights, was recently introduced in the management of this condition. Thanks to its therapeutic and biomodulating action on the irradiated tissues, PBM can be used alone or in combination with antibiotic and antibacterial therapies as a preventive, antalgic or palliative tool, and in support of surgery in a combined multi-protocol that leads to a positive and better resolution and healing of the pathologic process, with great improvement of the Quality of Life (QoL) of the patients. In this narrative review, a wide analysis of the various applications of PBM in MRONJ patients’ management is analyzed, emphasizing its role as supportive care for this condition. Full article

Supernumerary teeth may be encountered as an incidental finding on a radiograph. When impacted, they may be associated with clinical signs related to different problems such as failure of eruption, teeth displacement, root resorption or cystic lesions. They may occur in primary and permanent dentition, in both the maxilla and mandible and can be single or multiple in patients with syndromes. Mesiodens is the most commonly impacted tooth and appears between the central maxillary incisors in pediatric ages. Supernumerary teeth distal to the third molar are rare, usually impacted and referred to as a distomolar. A 46-year-old male consulted with the main complaint of pain on the left side of the maxilla. A panoramic radiograph revealed a right impacted maxillary fourth molar located posterior to the third molar associated with a pericoronal radiolucency. The supernumerary tooth was removed surgically under local anesthesia and the pericoronal lesion enucleated. Histopathological examination was consistent with the diagnosis of a dentigerous cyst associated with an impacted distomolar. Healing was uneventful, and the patients remained asymptomatic. The occurrence of an impacted maxillary distomolar is rare and even rarer the association with a dentigerous cyst. Full article

Total edentulism is the loss of all teeth for any cause by a multifactorial process that involves biological and patient-related factors. Studies on edentulism and risk factors in Mexico are limited, and the epidemiological surveillance data is scarce and controversial since official governmental reports are not statistically representative of the country. We estimate the distribution for edentulism according to sociodemographic and socioeconomic variables in adults from a low-income state in 2003 and its progress in Mexico. We analyzed data from the National Performance Evaluation Survey in Oaxaca, Mexico, and the annual reports of the Epidemiological Surveillance System of Oral Pathologies in 2009–2019 using X². Oaxacan patients older than 75 y.o. (17.9%, p < 0.05), those with lower schooling (11.2%), and diabetes (14.5%) presented the highest percentage of edentulism. We do not observe differences in edentulism between sex or residence (p > 0.05). From 2009 to 2019, country data reports the lowest rate of edentulism in adults over 20 y.o. (0.32%; 95% CI 0.18–0.48%) and the most affected population over 79 y.o. (7.29%; 95% CI 5.2–9.30%). As it is a cumulative phenomenon, it is necessary to establish better surveillance, prevention, and treatment programs to improve the oral health of older thus reducing edentulism. Full article

Objective: The question of whether classic cast post-and-core (CPC) or fiber-reinforced composite resin posts (FRCP) are the best clinical decision has still not been fully solved. Materials and Methods: One hundred and sixty-two teeth were restored with FRCP, and 162 CPC restored teeth were included in this study with a matched-pair design. In a primary analysis, the survival rates after one year (primary endpoint) were compared. The additional analysis included an evaluation of tooth- and construction-specific variables and an illustration of the survival up to 60 months via Kaplan-Meier curves. Results: FRCP showed lower failure risk considering the definitive prosthetic restoration and tooth type compared to CPC restored teeth. In total, 17 failures were observed in the FRCP group and 35 failures in the CPC group. A 60-month survival rate of 79.3% for FRCP and 64.5% for CPC was observed. Teeth serving as abutments for telescopic dentures were more likely to be affected by failure compared to teeth restored with single crowns. Conclusion: Within the limitations of this study, the FRCP showed a lower failure risk compared to the CPC, considering the definitive prosthetic restoration and tooth type within the observation period. Full article

Proper maxillomandibular relationship registration can be clinically challenging during a digital workflow in full-arch rehabilitations. This dental technique requires the manufacturing and use of a hybrid surgical guide custom scanning device, indicated to be used during implant placement surgery, in addition to being used to simultaneously register the maxillomandibular relationship and transfer the implants’ 3D positioning, ensuring a fully digital workflow in full-arch implant-supported prosthesis rehabilitation. The sequence of steps presented here will allow dentists and dental technicians to conduct rehabilitations from denture to the final implant-supported prosthesis using a full-digital protocol, using a minimal quantity of intraoral devices and digital tools. Full article