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1.
J Prosthet Dent ; 130(4): 453-532, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37453884

RESUMEN

The Scientific Investigation Committee of the American Academy of Restorative Dentistry offers this review of the 2022 dental literature to briefly touch on several topics of interest to modern restorative dentistry. Each committee member brings discipline-specific expertise in their subject areas that include (in order of the appearance in this report): prosthodontics; periodontics, alveolar bone, and peri-implant tissues; dental materials and therapeutics; occlusion and temporomandibular disorders; sleep-related breathing disorders; oral medicine and oral and maxillofacial surgery; and dental caries and cariology. The authors focused their efforts on reporting information likely to influence the daily dental treatment decisions of the reader with an emphasis on innovations, new materials and processes, and future trends in dentistry. With the tremendous volume of literature published daily in dentistry and related disciplines, this review cannot be comprehensive. Instead, its purpose is to update interested readers and provide valuable resource material for those willing to subsequently pursue greater detail on their own. Our intent remains to assist colleagues in navigating the tremendous volume of newly minted information produced annually. Finally, we hope that readers find this work helpful in managing patients.

2.
J Prosthet Dent ; 128(3): 248-330, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36096911

RESUMEN

The Scientific Investigation Committee of the American Academy of Restorative Dentistry offers this review of the 2021 dental literature in restorative dentistry to inform busy dentists regarding noteworthy scientific and clinical progress over the past year. Each member of the committee brings discipline-specific expertise to coverage of this broad topical area. Specific subject areas addressed, in order of the appearance in this report, include COVID-19 and the dental profession (new); prosthodontics; periodontics, alveolar bone, and peri-implant tissues; implant dentistry; dental materials and therapeutics; occlusion and temporomandibular disorders; sleep-related breathing disorders; oral medicine and oral and maxillofacial surgery; and dental caries and cariology. The authors focused their efforts on reporting information likely to influence daily dental treatment decisions with an emphasis on future trends in dentistry. With the tremendous volume of dentistry and related literature being published daily, this review cannot possibly be comprehensive. Rather, its purpose is to update interested readers and provide important resource material for those interested in pursuing greater details on their own. It remains our intent to assist colleagues in negotiating the extensive volume of important information being published annually. It is our hope that readers find this work useful in successfully managing the patients and dental problems they encounter.


Asunto(s)
COVID-19 , Caries Dental , Atención Odontológica , Caries Dental/terapia , Materiales Dentales , Humanos , Prostodoncia , Estados Unidos
3.
J Prosthet Dent ; 126(3): 276-359, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34489050

RESUMEN

The Scientific Investigation Committee of the American Academy of Restorative Dentistry offers this review of the 2020 professional literature in restorative dentistry to inform busy dentists regarding noteworthy scientific and clinical progress over the past year. Each member of the committee brings discipline-specific expertise to this work to cover this broad topic. Specific subject areas addressed include prosthodontics; periodontics, alveolar bone, and peri-implant tissues; implant dentistry; dental materials and therapeutics; occlusion and temporomandibular disorders (TMDs); sleep-related breathing disorders; oral medicine and oral and maxillofacial surgery; and dental caries and cariology. The authors focused their efforts on reporting information likely to influence day-to-day dental treatment decisions with a keen eye on future trends in the profession. With the tremendous volume of dentistry and related literature being published today, this review cannot possibly be comprehensive. The purpose is to update interested readers and provide important resource material for those interested in pursuing greater detail. It remains our intent to assist colleagues in navigating the extensive volume of important information being published annually. It is our hope that readers find this work useful in successfully managing the dental patients they encounter.


Asunto(s)
Caries Dental , Atención Odontológica , Materiales Dentales , Humanos , Periodoncia , Prostodoncia , Estados Unidos
4.
J Prosthet Dent ; 124(3): 274-349, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32811666

RESUMEN

This comprehensive review of the 2019 restorative dental literature is offered to inform busy dentists regarding remarkable publications and noteworthy progress made in the profession. Developed by the Scientific Investigation Committee of the American Academy of Restorative Dentistry, each author brings discipline-specific expertise to 1 of 8 sections of the report: (1) prosthodontics; (2) periodontics, alveolar bone, and peri-implant tissues; (3) implant dentistry; (4) dental materials and therapeutics; (5) occlusion and temporomandibular disorders; (6) sleep-related breathing disorders; (7) oral medicine and oral and maxillofacial surgery; and (8) dental caries and cariology. The report targets important information likely to influence day-to-day dental treatment decisions. Each review is not intended to stand alone but to update interested readers so that they may visit source material when greater detail is desired. As the profession moves toward evidence-based clinical decision-making, an incredible volume of potentially valuable dental literature continues to increase. It is the intention of this review and its authors to provide assistance in negotiating the extensive dental literature published in 2019. It is our hope that readers find this work useful in the clinical management of dental patients.


Asunto(s)
Caries Dental , Materiales Dentales , Oclusión Dental , Humanos , Periodoncia , Prostodoncia , Estados Unidos
5.
Dent Clin North Am ; 63(4): 731-736, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31470926

RESUMEN

Caries management could provide a unique opportunity to model reform to the dental reimbursement system. To be successful we must first understand the scope and basis of many of the obstacles to reform. Reform must also provide value to all the players involved in benefit determination, provision of care, and payment for care. Value is viewed as outcomes achieved per dollar from the patient's perspective and over a complete cycle of care or management. Reimbursing for value requires measurement of value, and one hypothetical model for caries management is presented based on Michael Porter's hierarchy of outcome measures.


Asunto(s)
Caries Dental , Humanos
6.
J Prosthet Dent ; 122(3): 198-269, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31405523

RESUMEN

This comprehensive review of the 2018 dental literature is provided to inform busy dentists about progress in the profession. Developed by the Committee on Scientific Investigation of the American Academy of Restorative Dentistry, each author brings discipline-specific expertise to one of the 8 sections of the report including (1) prosthodontics; (2) periodontics, alveolar bone, and peri-implant tissues; (3) implant dentistry; (4) dental materials and therapeutics; (5) occlusion and temporomandibular disorders; (6) sleep-related breathing disorders; (7) oral medicine and oral and maxillofacial surgery; and (8) dental caries and cariology. The report targets important information that will likely influence day-to-day treatment decisions. Each review is not intended to stand alone but to update interested readers so that they may visit source materials if greater detail is desired. As the profession continues its march toward evidence-based clinical decision-making, an already voluminous library of potentially valuable dental literature continues to grow. It is the intention of this review and its authors to provide assistance in navigating the extensive dental literature published in 2018. It is our hope that readers find this work useful in the clinical management of patients moving forward.


Asunto(s)
Caries Dental , Materiales Dentales , Oclusión Dental , Humanos , Periodoncia , Prostodoncia , Estados Unidos
7.
Clin Cosmet Investig Dent ; 11: 157-162, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31354361

RESUMEN

Objective: This study compared attendees at Wisconsin Mission of Mercy (MoM) events with and without prior emergency department (ED) visits for dental care in terms of demographic characteristics and dental procedures received. Methods: De-identified archival data available from the America's Dentists Care Foundation (2013-2016) were analyzed. Summary statistics were calculated based on prior ED visit status for county-level characteristics and type of dental procedures received. Generalized estimating equation models with logistic links were fitted to examine associations between the predictor and independent variables. Results: Most attendees were White, adult females (mean age 37 years). Current dental pain was reported by 61% vs 33% of attendees with and without prior ED visit. Cleaning (57%) was the most common procedure received by attendees with no prior ED visits, while extractions (47%) were the most common for those with prior ED visits. Among MoM attendees, males had higher odds of prior ED visits compared to females. Compared to White, Black had higher odds and Hispanic had lower odds of having prior ED visits. In the multivariable analysis, dental pain (OR: 3.32; 95% CI: 2.75, 4.02) had the strongest association with prior ED visits. Attendees with prior ED visit history had higher odds of receiving extractions and restorative care, compared to cleaning after adjustment for person and county-level characteristics. Conclusion: Among MoM attendees, prior ED visits were associated with not being Hispanic, being male, and having dental pain. Compared to attendees with no prior ED visit, those with prior ED visits had higher odds of receiving restorative care and extractions.

8.
J Prosthet Dent ; 120(6): 816-878, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30545471

RESUMEN

PROBLEM: There are countless numbers of scientific studies published in countless scientific journals on subjects related to restorative dentistry. PURPOSE: The purpose of this article is to review pertinent scientific studies published in 2017 on topics of interest to restorative dentists. METHODS AND MATERIALS: The authors, considered to be experts in their disciplines searched the scientific literature in 7 different areas (prosthodontics, periodontics, dental materials, occlusion and temporomandibular disorders, sleep-disordered breathing, oral medicine and oral and maxillofacial surgery and dental caries). Pertinent articles were either identified and referenced or reviewed. RESULTS: A total of 437 articles in 7 disciplines were identified or reviewed. CONCLUSIONS: An impressive amount of scientific literature related to restorative dentistry was published in 2017. The evidence presented in this article can assist dentists in the practice of contemporary evidence-based dentistry.


Asunto(s)
Investigación Dental , Enfermedades de la Boca/terapia , Prostodoncia , Cirugía Bucal , Bibliometría , Caries Dental/terapia , Materiales Dentales , Oclusión Dental , Odontología Basada en la Evidencia , Humanos , Síndromes de la Apnea del Sueño/terapia , Trastornos de la Articulación Temporomandibular/terapia
9.
J Endod ; 44(2): 220-225, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29229456

RESUMEN

INTRODUCTION: The objective of this study was to determine the effect of delayed placement of the core/post and crown on the outcomes of nonsurgical root canal therapy (NSRCT). METHODS: According to the Delta Dental of Wisconsin claims database, 160,040 NSRCTs were completed with a core/post and a crown placed before the end of the continuous coverage period or occurrence of an untoward event. Untoward events were defined as a retreatment, apicoectomy, or extraction as defined by the Code on Dental Procedures and Nomenclature. Statistical analysis was performed by using a multivariable Cox proportional hazards model. RESULTS: The survival rate from the time of crown placement to an untoward event was 99.1% at 1 year, 96.0% at 3 years, 92.3% at 5 years, and 83.8% at 10 years. Failure rates were greater when a core/post was placed more than 60 days after the NSRCT (adjusted hazard ratio, 1.08) and when the crown was placed more than 60 days after the core/post placement (adjusted hazard ratio, 1.14). Overall, the survival rates of NSRCT were greater when performed by an endodontist versus other providers. CONCLUSIONS: On the basis of the information available from insurance claims data, this study shows that the long-term survival rates of initial endodontic therapy are adversely affected by the delayed placement of the final restoration and full coverage crown.


Asunto(s)
Coronas , Técnica de Perno Muñón , Diente no Vital/terapia , Adolescente , Adulto , Anciano , Niño , Preescolar , Coronas/efectos adversos , Fracaso de la Restauración Dental/estadística & datos numéricos , Restauración Dental Permanente/efectos adversos , Restauración Dental Permanente/métodos , Humanos , Lactante , Persona de Mediana Edad , Técnica de Perno Muñón/efectos adversos , Tratamiento del Conducto Radicular/métodos , Adulto Joven
10.
J Prosthet Dent ; 118(3): 281-346, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28709678

RESUMEN

This review was conducted to assist the busy dentist in keeping abreast of the latest scientific information regarding the clinical practice of dentistry. Each of the authors, who are considered experts in their disciplines, was asked to peruse the scientific literature in their discipline published in 2016 and review the articles for important information that may affect treatment decisions. Comments on experimental methodology, statistical evaluation, and the overall validity of conclusions are included with many of the reviews. The reviews are not meant to stand alone but are intended to inform the interested reader about what has been discovered in the past year. The readers are then invited to go to the source, if they want more detail.


Asunto(s)
Atención Odontológica , Investigación Dental , Odontología , Medicina Basada en la Evidencia , Humanos
11.
J Am Dent Assoc ; 147(5): 313-4, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-27126311
12.
J Endod ; 42(5): 702-5, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27004720

RESUMEN

INTRODUCTION: The objective of this study was to compare the outcomes of initial nonsurgical root canal therapy for different tooth types provided by both endodontists and other providers. METHODS: By using an insurance company database, 487,476 initial nonsurgical root canal therapy procedures were followed from the time of treatment to the presence of an untoward event indicated by Current Dental Terminology codes for retreatment, apical surgery, or extraction. Population demographics were computed for provider type and tooth location. Kaplan-Meier survival estimates were calculated for 1, 5, and 10 years. Hazard ratios for provider type and tooth location were calculated by using the Cox proportional hazards model. RESULTS: The survival of all teeth collectively was 98% at 1 year, 92% at 5 years, and 86% at 10 years. Significant differences in survival on the basis of provider type were noted for molars at 5 years and for all tooth types at 10 years. The greatest difference discovered was 5% higher survival rate at 10 years for molars treated by endodontists. A hazard ratio of 1.394 was found when comparing other providers' success with that of endodontists within this 10-year molar group. CONCLUSIONS: These findings show that survival rates of endodontically treated teeth are high at 10 years after treatment regardless of provider type. Molars treated by endodontists after 10 years have significantly higher survival rates than molars treated by non-endodontists.


Asunto(s)
Endodoncia , Tratamiento del Conducto Radicular , Resultado del Tratamiento , Diente Premolar , Odontólogos , Humanos , Incisivo , Seguro , Diente Molar , Modelos de Riesgos Proporcionales , Retratamiento , Tratamiento del Conducto Radicular/métodos , Tratamiento del Conducto Radicular/estadística & datos numéricos , Tasa de Supervivencia , Ápice del Diente/cirugía , Extracción Dental , Diente no Vital , Wisconsin
13.
J Prosthet Dent ; 116(5): 663-740, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28236412

RESUMEN

STATEMENT OF PROBLEM: It is clear the contemporary dentist is confronted with a blizzard of information regarding materials and techniques from journal articles, advertisements, newsletters, the internet, and continuing education events. While some of that information is sound and helpful, much of it is misleading at best. PURPOSE: This review identifies and discusses the most important scientific findings regarding outcomes of dental treatment to assist the practitioner in making evidence-based choices. This review was conducted to assist the busy dentist in keeping abreast of the latest scientific information regarding the clinical practice of dentistry. MATERIAL AND METHODS: Each of the authors, who are considered experts in their disciplines, was asked to peruse the scientific literature published in 2015 in their discipline and review the articles for important information that may have an impact on treatment decisions. Comments on experimental methodology, statistical evaluation, and overall validity of the conclusions are included in many of the reviews. RESULTS: The reviews are not meant to stand alone but are intended to inform the interested reader about what has been discovered in the past year. The readers are then invited to go to the source if they wish more detail. CONCLUSIONS: Analysis of the scientific literature published in 2015 is divided into 7 sections, dental materials, periodontics, prosthodontics, occlusion and temporomandibular disorders, sleep-disordered breathing, cariology, and implant dentistry.


Asunto(s)
Atención Odontológica , Odontología , Humanos
16.
Proc Inst Mech Eng H ; 228(8): 754-67, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25205746

RESUMEN

In nature, an interface between dissimilar tissues is often bridged by a graded zone, and provides functional properties at a whole organ level. A perfect example is a "biological interphase" between stratified cementum and dentin of a narwhal tooth. This study highlights the graded structural, mechanical, and chemical natural characteristics of a biological interphase known as the cementum-dentin junction layer and their effect in resisting mechanical loads. From a structural perspective, light and electron microscopy techniques illustrated the layer as a wide 1000-2000 µm graded zone consisting of higher density continuous collagen fiber bundles from the surface of cementum to dentin, that parallels hygroscopic 50-100 µm wide collagenous region in human teeth. The role of collagen fibers was evident under compression testing during which the layer deformed more compared to cementum and dentin. This behavior is reflected through site-specific nanoindentation indicating a lower elastic modulus of 2.2 ± 0.5 GPa for collagen fiber bundle compared to 3 ± 0.4 GPa for mineralized regions in the layer. Similarly, microindentation technique illustrated lower hardness values of 0.36 ± 0.05 GPa, 0.33 ± 0.03 GPa, and 0.3 ± 0.07 GPa for cementum, dentin, and cementum-dentin layer, respectively. Biochemical analyses including Raman spectroscopy and synchrotron-source microprobe X-ray fluorescence demonstrated a graded composition across the interface, including a decrease in mineral-to-matrix and phosphate-to-carbonate ratios, as well as the presence of tidemark-like bands with Zn. Understanding the structure-function relationships of wider tissue interfaces can provide insights into natural tissue and organ function.


Asunto(s)
Cemento Dental/química , Cemento Dental/fisiología , Dentina/química , Dentina/fisiología , Ballenas/fisiología , Animales , Fenómenos Biomecánicos , Colágeno/química , Colágeno/fisiología , Interferometría , Masculino , Microscopía de Fuerza Atómica , Espectrometría Raman , Microtomografía por Rayos X
17.
Anat Rec (Hoboken) ; 297(4): 599-617, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24639076

RESUMEN

The erupted tusk of the narwhal exhibits sensory ability. The hypothesized sensory pathway begins with ocean water entering through cementum channels to a network of patent dentinal tubules extending from the dentinocementum junction to the inner pulpal wall. Circumpulpal sensory structures then signal pulpal nerves terminating near the base of the tusk. The maxillary division of the fifth cranial nerve then transmits this sensory information to the brain. This sensory pathway was first described in published results of patent dentinal tubules, and evidence from dissection of tusk nerve connection via the maxillary division of the fifth cranial nerve to the brain. New evidence presented here indicates that the patent dentinal tubules communicate with open channels through a porous cementum from the ocean environment. The ability of pulpal tissue to react to external stimuli is supported by immunohistochemical detection of neuronal markers in the pulp and gene expression of pulpal sensory nerve tissue. Final confirmation of sensory ability is demonstrated by significant changes in heart rate when alternating solutions of high-salt and fresh water are exposed to the external tusk surface. Additional supporting information for function includes new observations of dentinal tubule networks evident in unerupted tusks, female erupted tusks, and vestigial teeth. New findings of sexual foraging divergence documented by stable isotope and fatty acid results add to the discussion of the functional significance of the narwhal tusk. The combined evidence suggests multiple tusk functions may have driven the tooth organ system's evolutionary development and persistence.


Asunto(s)
Pulpa Dental/fisiología , Sensación/fisiología , Diente/fisiología , Animales , Pulpa Dental/inervación , Dieta , Femenino , Expresión Génica , Microscopía Electrónica de Rastreo , Neurofisiología , Diente/anatomía & histología , Ballenas
18.
J Am Dent Assoc ; 143(12): 1292-302, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23204083

RESUMEN

BACKGROUND: Bisphenol A (BPA) and other related chemical compounds may be components used in the manufacturing process of resin-based composite dental restorative material. The purpose of the authors' study was to assess salivary and urinary concentrations of BPA and other compounds before and after placement of resin-based composite dental restorations. METHODS: The authors collected saliva and urine from 172 participants receiving composite restorations before and as long as 30 hours after placement of composite restorations. The authors analyzed saliva specimens from 151 participants and urine specimens from 171 participants for concentrations of BPA and five related compounds by using liquid chromatography/mass spectrometry (LC/MS). RESULTS: Salivary concentrations of BPA and some related compounds increased immediately (within one hour) after composite placement. Salivary concentrations of BPA and most study compounds returned to prerestoration levels within eight hours after composite placement. With the exception of a 43 percent increase in BPA, concentrations of the study compounds in urine returned to prerestoration levels nine to 30 hours after restoration placement. Concentrations in saliva were lower when a rubber dam was used; however, rubber dam use appeared to have no effect on urinary concentrations of the measured compounds during the study period. The authors observed similar changes in study compound levels in both saliva and urine between participants who received anterior restorations and those who received posterior restorations. CONCLUSIONS: Placement of resin-based composite restorations was associated with detectable increases in saliva of BPA and other study compounds within one hour after restoration placement and an increased concentration of BPA in urine nine to 30 hours after restoration placement. Rubber dam use did not reduce the absorption of BPA (measured as BPA level in urine) during the study. CLINICAL IMPLICATIONS: Additional studies are needed to address how long BPA levels in urine associated with composite placement remain elevated to aid in better understanding of the clearance rates of BPA and other study compounds.


Asunto(s)
Compuestos de Bencidrilo/análisis , Resinas Compuestas/análisis , Materiales Dentales/análisis , Restauración Dental Permanente , Fenoles/análisis , Saliva/química , Resinas Acrílicas/química , Adulto , Compuestos de Bencidrilo/química , Compuestos de Bencidrilo/orina , Cromatografía Liquida , Resinas Compuestas/química , Materiales Dentales/química , Compuestos Epoxi/análisis , Femenino , Estudios de Seguimiento , Humanos , Masculino , Espectrometría de Masas , Metacrilatos/análisis , Fenoles/química , Fenoles/orina , Polietilenglicoles/análisis , Ácidos Polimetacrílicos/análisis , Poliuretanos/química , Dique de Goma
19.
Head Neck Oncol ; 4: 15, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22537712

RESUMEN

BACKGROUND: Head and neck cancers are of particular interest to health care providers, their patients, and those paying for health care services, because they have a high morbidity, they are extremely expensive to treat, and of the survivors only 48% return to work. Consequently the economic burden of oral cavity, oral pharyngeal, and salivary gland cancer (OC/OP/SG) must be understood. The cost of these cancers in the U.S. has not been investigated. METHODS: A retrospective analysis of administrative claims data for 6,812 OC/OP/SG cancer patients was undertaken. Total annual health care spending for OC/OP/SG cancer patients was compared to similar patients without OC/OP/SG cancer using propensity score matching for enrollees in commercial insurance, Medicare, and Medicaid. Indirect costs, as measured by short term disability days were compared for employed patients. RESULTS: Total annual health care spending for OC/OP/SG patients during the year after the index diagnosis was $79,151 for the Commercial population. Health care costs were higher for OC/OP/SG cancer patients with Commercial Insurance ($71,732, n = 3,918), Medicare ($35,890, n = 2,303) and Medicaid ($44,541, n = 585) than the comparison group (all p < 0.01). Commercially-insured employees with cancer (n = 281) had 44.9 more short-term disability days than comparison employees (p < 0.01). Multimodality treatment was twice the cost of single modality therapy. Those patients receiving all three treatments (surgery, radiation, and chemotherapy) had the highest costs of cost of care, from $96,520 in the Medicare population to $153,892 in the Commercial population. CONCLUSIONS: In the U.S., the cost of OC/OP/SG cancer is significant and may be the most costly cancer to treat in the U.S. The results of this analysis provide useful information to health care providers and decision makers in understanding the economic burden of head and neck cancer. Additionally, this cost information will greatly assist in determining the cost-effectiveness of new technologies and early detection systems. Earlier identification of cancers by patients and providers may potentially decrease health care costs, morbidity and mortality.


Asunto(s)
Seguro de Salud/economía , Medicaid/economía , Medicare/economía , Neoplasias de la Boca/economía , Neoplasias Faríngeas/economía , Neoplasias de las Glándulas Salivales/economía , Costo de Enfermedad , Femenino , Costos de la Atención en Salud , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Estados Unidos
20.
Anat Rec (Hoboken) ; 295(6): 1006-16, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22467529

RESUMEN

Narwhal tusks, although well described and characterized within publications, are clouded by contradictory references, which refer to them as both incisors and canines. Vestigial teeth are briefly mentioned in the scientific literature with limited descriptions and no image renderings. This study first examines narwhal maxillary osteoanatomy to determine whether the erupted tusks are best described as incisiform or caniniform teeth. The study also offers evidence to support the evolutionary obsolescence of the vestigial teeth through anatomic, morphologic, and histologic descriptions. Examination of 131 skull samples, including 110 museum skull specimens and 21 harvested skulls, revealed the erupted tusks surrounded by maxillary bone over the entire length of their bone socket insertion, and are thus more accurately termed caniniform or canine teeth. The anatomy, morphology, and development of vestigial teeth in five skull samples are more fully described and documented. Vestigial tooth samples included 14 embedded pairs or individual teeth that were partially exposed or removed from the maxillary bone. Their location was posterior, ventral, and lateral to the tusks, although male vestigial teeth often exfoliate in the mouth lodging between the palatal tissue and underlying maxillary bone. Their myriad morphologies, sizes, and eruption patterns suggest that these teeth are no longer guided by function but rather by random germ cell differentiation and may eventually cease expression entirely. The conclusions reached are that the narwhal tusks are the expression of canine teeth and that vestigial teeth have no apparent functional characteristics and are following a pattern consistent with evolutionary obsolescence.


Asunto(s)
Diente/anatomía & histología , Ballenas/anatomía & histología , Animales , Femenino , Masculino , Cráneo/anatomía & histología , Terminología como Asunto
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