Davis Nasal Projectometer

Nasal Projection Measuring Instrument for Rhinoplasty Assessment and Intraoperative Nasal Measurement

Davis Nasal Projectometer is a nasal projection and angulation measuring instrument in the measuring and marking instruments category, designed by Richard E. Davis, MD and manufactured by BusinessMed Instruments®, used in Plastic Surgery, ENT (Otorhinolaryngology), Facial Plastic Surgery, and Rhinoplasty.

Davis Nasal Projectometer measures radix projection, rhinion projection, nasal tip projection, and nasolabial angle simultaneously across four independent measurement points, used in primary rhinoplasty, revision rhinoplasty, nasal reconstruction, preoperative nasal assessment, intraoperative nasal measurement, and postoperative outcome assessment. ────────────────────────────────────────────────────────────────────

Occlusal Registration and Biaxial Measurement Architecture

The dental occlusal stop registers against the dentition to eliminate instrument drift across all four sequential measurement points. Three removable calibrated sliding pins displace along the biaxial X-Y calibration arms to capture radix, rhinion, and nasal tip projection values in millimetres; the fixed tilting nasolabial pin localizes to the columellar-labial junction and measures nasolabial angle as angular displacement within the same frame. Where surgeons require reproducible craniofacial positional registration across sequential rhinoplasty measurements, the occlusal registration approach — conventionally associated with orthognathic surgery — eliminates the positional drift that affects single-anchor calipers. No comparable single-instrument architecture captures four simultaneous independent craniofacial measurement points with occlusal registration as the positional anchor.

Nasolabial Angle Norms and Projection Outcome Targets

Projection values at all four measurement points directly inform surgical decisions on osteotomy, tip grafting, dorsal reduction, and columellar modification. Nasolabial angle readings are referenced against published norms — 90–95° in male patients, 95–110° in female patients — to prevent nasal tip over-projection, under-projection, and inadequate nasolabial angle correction. Cross-phase utility spans preoperative assessment, intraoperative measurement, and postoperative outcome evaluation within a single reusable instrument.

Clinical Uses and Applications

• Radix projection at the nasal root is measured intraoperatively during primary rhinoplasty via biaxial X-Y calibrated sliding arm placement.
• Rhinion projection is measured intraoperatively via independent calibrated sliding arm displacement at the nasal dorsum midpoint during primary rhinoplasty.
• Nasal tip projection is measured intraoperatively via removable calibrated sliding pin placement during primary rhinoplasty and revision rhinoplasty.
• Nasolabial angle is measured at the columellar-labial junction via the fixed tilting nasolabial pin during primary rhinoplasty and revision rhinoplasty.
• Radix, rhinion, nasal tip, and nasolabial angle are assessed preoperatively prior to primary or revision rhinoplasty procedures using all four measurement points.
• Nasal projection and nasolabial angle are evaluated postoperatively following rhinoplasty or nasal reconstruction, referenced against the 90–95° male and 95–110° female published norms.
• In revision rhinoplasty cases, asymmetric radix and rhinion projection values are captured simultaneously on independent X and Y axes without instrument repositioning.
• Nasal tip projection and nasolabial angle data from all four measurement points inform surgical decisions on osteotomy, tip grafting, dorsal reduction, and columellar modification.

Associated Instruments

• Nasal ruler / caliper — used in rhinoplasty measurement workflow alongside the projectometer as a linear reference measurement instrument.
• Skin marking pen — used in preoperative nasal assessment for midline marking within the same preoperative sequence.