CENTRAL NERVOUS SYSTEM MECHANISMS AND PAIN MODULATION AND RESPONSE TO LOCAL ANESTHESIA IN DENTISTRY: A LITERATURE REVIEW

Abstract

Pain processing in patients with pulpal pain, particularly symptomatic irreversible pulpitis, involves not only peripheral inflammation but also pain processing within the central nervous system (CNS). This literature review aimed to synthesize recent evidence on CNS mechanisms of pain modulation and their clinical implications for the response to local anesthesia in dentistry. A narrative literature review was conducted using PubMed, Google Scholar, ScienceDirect, and Wiley Online Library. Studies published from 2021 to 2026 were prioritized, including experimental studies, randomized controlled trials, observational studies, systematic reviews, meta-analyses, and narrative reviews relevant to CNS pain mechanisms, pain modulation, and local anesthesia in dentistry. The selected literature was descriptively synthesized into three themes: CNS mechanisms of pain, central pain modulation, and clinical response to local anesthesia. The findings indicate that central sensitization, neuroplasticity, N-methyl-D-aspartate receptor-mediated signaling, trigeminal pain pathways, and psychological factors contribute to the amplification and persistence of orofacial pain. Local anesthetic success, particularly in symptomatic irreversible pulpitis, is influenced by multiple factors, including inflammation, anatomical conditions, anesthetic technique, and individual pain processing. Supplemental techniques, including intraligamentary, intraosseous, and computer-controlled anesthesia, may improve anesthetic outcomes or procedural comfort under specific conditions. Overall, CNS pain modulation contributes to individual variability in dental pain, although current evidence does not establish central sensitization as a direct cause of local anesthetic failure. Understanding central and peripheral pain mechanisms may support individualized pain-management strategies in dentistry.

ABSTRAK

Kegagalan atau ketidakoptimalan anestesi lokal pada kondisi nyeri pulpa, khususnya symptomatic irreversible pulpitis, tidak hanya berkaitan dengan inflamasi perifer, tetapi juga dengan pemrosesan nyeri pada sistem saraf pusat (SSP). Literature review ini bertujuan untuk mensintesis bukti terkini mengenai mekanisme SSP dalam modulasi nyeri serta implikasinya terhadap respons terhadap anestesi lokal dalam kedokteran gigi. Literature review naratif dilakukan melalui pencarian pada PubMed, Google Scholar, ScienceDirect, dan Wiley Online Library. Studi yang dipublikasikan pada tahun 2021–2026 diprioritaskan, meliputi studi eksperimental, randomized controlled trial, studi observasional, systematic review, meta-analysis, dan narrative review yang relevan dengan mekanisme nyeri pada SSP, modulasi nyeri, dan anestesi lokal dalam kedokteran gigi. Literatur yang terpilih disintesis secara deskriptif ke dalam tiga tema utama, yaitu mekanisme SSP terhadap nyeri, modulasi nyeri sentral, dan respons klinis terhadap anestesi lokal. Hasil menunjukkan bahwa sensitisasi sentral, neuroplastisitas, sinyal yang dimediasi reseptor N-methyl-D-aspartate, jalur trigeminal, serta faktor psikologis berperan dalam amplifikasi dan persistensi nyeri orofasial. Keberhasilan anestesi lokal, terutama pada symptomatic irreversible pulpitis, dipengaruhi oleh berbagai faktor, termasuk inflamasi, kondisi anatomis, teknik anestesi, dan pemrosesan nyeri individu. Teknik tambahan seperti anestesi intraligamenter, intraosseous, dan computer-controlled dapat meningkatkan kenyamanan atau efektivitas klinis pada kondisi tertentu. Secara keseluruhan, modulasi nyeri oleh SSP berkontribusi terhadap variasi respons nyeri, tetapi belum terdapat bukti yang cukup bahwa sensitisasi sentral secara langsung menyebabkan kegagalan anestesi lokal.